WorldWideScience

Sample records for lymphocyte effector differentiation

  1. New insights into Blimp-1 in T lymphocytes: a divergent regulator of cell destiny and effector function.

    Science.gov (United States)

    Fu, Shin-Huei; Yeh, Li-Tzu; Chu, Chin-Chen; Yen, B Lin-Ju; Sytwu, Huey-Kang

    2017-07-21

    B lymphocyte-induced maturation protein-1 (Blimp-1) serves as a master regulator of the development and function of antibody-producing B cells. Given that its function in T lymphocytes has been identified within the past decade, we review recent findings with emphasis on its role in coordinated control of gene expression during the development, differentiation, and function of T cells. Expression of Blimp-1 is mainly confined to activated T cells and is essential for the production of interleukin (IL)-10 by a subset of forkhead box (Fox)p3 + regulatory T cells with an effector phenotype. Blimp-1 is also required to induce cell elimination in the thymus and critically modulates peripheral T cell activation and proliferation. In addition, Blimp-1 promotes T helper (Th) 2 lineage commitment and limits Th1, Th17 and follicular helper T cell differentiation. Furthermore, Blimp-1 coordinates with other transcription factors to regulate expression of IL-2, IL-21 and IL-10 in effector T lymphocytes. In CD8 + T cells, Blimp-1 expression is distinct in heterogeneous populations at the stages of clonal expansion, differentiation, contraction and memory formation when they encounter antigens. Moreover, Blimp-1 plays a fundamental role in coordinating cytokine receptor signaling networks and transcriptional programs to regulate diverse aspects of the formation and function of effector and memory CD8 + T cells and their exhaustion. Blimp-1 also functions as a gatekeeper of T cell activation and suppression to prevent or dampen autoimmune disease, antiviral responses and antitumor immunity. In this review, we discuss the emerging roles of Blimp-1 in the complex regulation of gene networks that regulate the destiny and effector function of T cells and provide a Blimp-1-dominated transcriptional framework for T lymphocyte homeostasis.

  2. CD4+ T cells are required to contain early extrathoracic TB dissemination and sustain multi-effector functions of CD8+ T and CD3− lymphocytes

    Science.gov (United States)

    Yao, Shuyu; Huang, Dan; Chen, Crystal Y.; Halliday, Lisa; Wang, Richard C.; Chen, Zheng W.

    2014-01-01

    The possibility that CD4+ T cells can act as “innate-like” cells to contain very-early M. tuberculosis (Mtb) dissemination and function as master helpers to sustain multiple effector functions of CD8+ T cells and CD3-negative lymphocytes during development of adaptive immunity against primary tuberculosis(TB) has not been demonstrated. We showed that pulmonary Mtb infection of CD4-depleted macaques surprisingly led to very-early extrathoracic Mtb dissemination, whereas CD4 deficiency clearly resulted in rapid TB progression. CD4 depletion during Mtb infection revealed the ability of CD8+ T cells to compensate and rapidly differentiate to Th17-like/Th1-like, and cytotoxic-like effectors, but these effector functions were subsequently unsustainable due to CD4 deficiency. While CD3-negative non-T lymphocytes in presence of CD4+ T cells developed predominant Th22-like and NK-like (perforin production) responses to Mtb infection, CD4 depletion abrogated these Th22-/NK-like effector functions and favored IL-17 production by CD3-negative lymphocytes. CD4-depleted macaques exhibited no or few pulmonary T effector cells constitutively producing IFN-γ, TNFα, IL-17, IL-22, and perforin at the endpoint of more severe TB, but presented pulmonary IL-4+ T effectors. TB granulomas in CD4-depleted macaques contained fewer IL-22+ and perforin+ cells despite presence of IL-17+ and IL-4+ cells. These results implicate previously-unknown “innate-like” ability of CD4+ T cells to contain extrathoracic Mtb dissemination at very early stage. Data also suggest that CD4+ T cells are required to sustain multiple effector functions of CD8+ T cells and CD3-negative lymphocytes and to prevent rapid TB progression during Mtb infection of nonhuman primates. PMID:24489088

  3. INFLUENCE OF MODIFIED BIOFLAVONOIDS UPON EFFECTOR LYMPHOCYTES IN MURINE MODEL OF CONTACT SENSITIVITY

    Directory of Open Access Journals (Sweden)

    D. Z. Albegova

    2015-01-01

    Full Text Available Contact sensitivity reaction (CSR to 2,4-dinitrofluorobenzene (DNFB in mice is a model of in vivo immune response, being an experimental analogue to contact dermatitis in humans. CSR sensitization phase begins after primary contact with antigen, lasting for 10-15 days in humans, and 5-7 days, in mice. Repeated skin exposure to the sensitizing substance leads to its recognition and triggering immune inflammatory mechanisms involving DNFB-specific effector T lymphocytes. The CSR reaches its maximum 18-48 hours after re-exposure to a hapten. There is only scarce information in the literature about effects of flavonoids on CSR, including both stimulatory and inhibitory effects. Flavonoids possessed, predominantly, suppressive effects against the CSR development. In our laboratory, a model of contact sensitivity was reproduced in CBA mice by means of cutaneous sensitization by 2,4-dinitrofluorobenzene. The aim of the study was to identify the mechanisms of immunomodulatory action of quercetin dihydrate and modified bioflavonoids, using the method of adoptive transfer contact sensitivity by splenocytes and T-lymphocytes. As shown in our studies, a 30-min pre-treatment of splenocytes and T-lymphocytes from sensitized mice with modified bioflavonoids before the cell transfer caused complete prevention of contact sensitivity reaction in syngeneic recipient mice. Meanwhile, this effect was not associated with cell death induction due to apoptosis or cytotoxicity. Quercetin dihydrate caused only partially suppression the activity of adaptively formed T-lymphocytes, the contact sensitivity effectors. It was shown that the modified bioflavonoid more stronger suppress adoptive transfer of contact sensitivity in comparison with quercetin dehydrate, without inducing apoptosis of effector cells. Thus, the modified bioflavonoid is a promising compound for further studies in a model of contact sensitivity, due to its higher ability to suppress transfer of CSR with

  4. A Key Role for NF-κB Transcription Factor c-Rel in T-Lymphocyte-Differentiation and Effector Functions

    Directory of Open Access Journals (Sweden)

    Alexander Visekruna

    2012-01-01

    Full Text Available The transcription factors of the Rel/NF-κB family function as key regulators of innate and adoptive immunity. Tightly and temporally controlled activation of NF-κB-signalling pathways ensures prevention of harmful immune cell dysregulation, whereas a loss of control leads to pathological conditions such as severe inflammation, autoimmune disease, and inflammation-associated oncogenesis. Five family members have been identified in mammals: RelA (p65, c-Rel, RelB, and the precursor proteins NF-κB1 (p105 and NF-κB2 (p100, that are processed into p50 and p52, respectively. While RelA-containing dimers are present in most cell types, c-Rel complexes are predominately found in cells of hematopoietic origin. In T-cell lymphocytes, certain genes essential for immune function such as Il2 and Foxp3 are directly regulated by c-Rel. Additionally, c-Rel-dependent IL-12 and IL-23 transcription by macrophages and dendritic cells is crucial for T-cell differentiation and effector functions. Accordingly, c-Rel expression in T cells and antigen-presenting cells (APCs controls a delicate balance between tolerance and immunity. This review gives a selective overview on recent progress in understanding of diverse roles of c-Rel in regulating adaptive immunity.

  5. The Role of Lipid Metabolism in T Lymphocyte Differentiation and Survival

    Directory of Open Access Journals (Sweden)

    Duncan Howie

    2018-01-01

    Full Text Available The differentiation and effector functions of both the innate and adaptive immune system are inextricably linked to cellular metabolism. The features of metabolism which affect both arms of the immune system include metabolic substrate availability, expression of enzymes, transport proteins, and transcription factors which control catabolism of these substrates, and the ability to perform anabolic metabolism. The control of lipid metabolism is central to the appropriate differentiation and functions of T lymphocytes, and ultimately to the maintenance of immune tolerance. This review will focus on the role of fatty acid (FA metabolism in T cell differentiation, effector function, and survival. FAs are important sources of cellular energy, stored as triglycerides. They are also used as precursors to produce complex lipids such as cholesterol and membrane phospholipids. FA residues also become incorporated into hormones and signaling moieties. FAs signal via nuclear receptors and their channeling, between storage as triacyl glycerides or oxidation as fuel, may play a role in survival or death of the cell. In recent years, progress in the field of immunometabolism has highlighted diverse roles for FA metabolism in CD4 and CD8 T cell differentiation and function. This review will firstly describe the sensing and modulation of the environmental FAs and lipid intracellular signaling and will then explore the key role of lipid metabolism in regulating the balance between potentially damaging pro-inflammatory and anti-inflammatory regulatory responses. Finally the complex role of extracellular FAs in determining cell survival will be discussed.

  6. Differential requirements of CD4(+) T-cell signals for effector cytotoxic T-lymphocyte (CTL) priming and functional memory CTL development at higher CD8(+) T-cell precursor frequency.

    Science.gov (United States)

    Umeshappa, Channakeshava S; Nanjundappa, Roopa H; Xie, Yufeng; Freywald, Andrew; Xu, Qingyong; Xiang, Jim

    2013-04-01

    Increased CD8(+) T-cell precursor frequency (PF) precludes the requirement of CD4(+) helper T (Th) cells for primary CD8(+) cytotoxic T-lymphocyte (CTL) responses. However, the key questions of whether unhelped CTLs generated at higher PF are functional effectors, and whether unhelped CTLs can differentiate into functional memory cells at higher PF are unclear. In this study, ovalbumin (OVA) -pulsed dendritic cells (DC(OVA)) derived from C57BL/6, CD40 knockout (CD40(-/-)) or CD40 ligand knockout (CD40L(-/-)) mice were used to immunize C57BL/6, Ia(b-/-), CD40(-/-) or CD40L(-/-) mice, whose PF was previously increased with transfer of 1 × 10(6) CD8(+) T cells derived from OVA-specific T-cell receptor (TCR) transgenic OTI, OTI(CD40(-/-)) or OTI(CD40L(-/-)) mice. All the immunized mice were then assessed for effector and memory CTL responses. Following DC immunization, relatively comparable CTL priming occurred without CD4(+) T-cell help and Th-provided CD40/CD40L signalling. In addition, the unhelped CTLs were functional effectors capable of inducing therapeutic immunity against established OVA-expressing tumours. In contrast, the functional memory development of CTLs was severely impaired in the absence of CD4(+) T-cell help and CD40/CD40L signalling. Finally, unhelped memory CTLs failed to protect mice against lethal tumour challenge. Taken together, these results demonstrate that CD4(+) T-cell help at higher PF, is not required for effector CTL priming, but is required for functional memory CTL development against cancer. Our data may impact the development of novel preventive and therapeutic approaches in cancer patients with compromised CD4(+) T-cell functions. © 2012 Blackwell Publishing Ltd.

  7. Lymphocyte gene expression signatures from patients and mouse models of hereditary hemochromatosis reveal a function of HFE as a negative regulator of CD8+ T-lymphocyte activation and differentiation in vivo.

    Science.gov (United States)

    Costa, Mónica; Cruz, Eugénia; Oliveira, Susana; Benes, Vladimir; Ivacevic, Tomi; Silva, Maria João; Vieira, Inês; Dias, Francisco; Fonseca, Sónia; Gonçalves, Marta; Lima, Margarida; Leitão, Catarina; Muckenthaler, Martina U; Pinto, Jorge; Porto, Graça

    2015-01-01

    Abnormally low CD8+ T-lymphocyte numbers is characteristic of some patients with hereditary hemochromatosis (HH), a MHC-linked disorder of iron overload. Both environmental and genetic components are known to influence CD8+ T-lymphocyte homeostasis but the role of the HH associated protein HFE is still insufficiently understood. Genome-wide expression profiling was performed in peripheral blood CD8+ T lymphocytes from HH patients selected according to CD8+ T-lymphocyte numbers and from Hfe-/- mice maintained either under normal or high iron diet conditions. In addition, T-lymphocyte apoptosis and cell cycle progression were analyzed by flow cytometry in HH patients. HH patients with low CD8+ T-lymphocyte numbers show a differential expression of genes related to lymphocyte differentiation and maturation namely CCR7, LEF1, ACTN1, NAA50, P2RY8 and FOSL2, whose expression correlates with the relative proportions of naïve, central and effector memory subsets. In addition, expression levels of LEF1 and P2RY8 in memory cells as well as the proportions of CD8+ T cells in G2/M cell cycle phase are significantly different in HH patients compared to controls. Hfe-/- mice do not show alterations in CD8+ T-lymphocyte numbers but differential gene response patterns. We found an increased expression of S100a8 and S100a9 that is most pronounced in high iron diet conditions. Similarly, CD8+ T lymphocytes from HH patients display higher S100a9 expression both at the mRNA and protein level. Altogether, our results support a role for HFE as a negative regulator of CD8+ T-lymphocyte activation. While the activation markers S100a8 and S100a9 are strongly increased in CD8+ T cells from both, Hfe-/- mice and HH patients, a differential profile of genes related to differentiation/maturation of CD8+ T memory cells is evident in HH patients only. This supports the notion that HFE contributes, at least in part, to the generation of low peripheral blood CD8+ T lymphocytes in HH.

  8. GENERATION OF CYTOTOXIC LYMPHOCYTES IN MIXED LYMPHOCYTE REACTIONS

    Science.gov (United States)

    Forman, James; Möller, Göran

    1973-01-01

    Generation of cytotoxic effector cells by a unidirectional mixed lymphocyte reaction (MLR) in the mouse H-2 system was studied using labeled YAC (H-2a) leukemia cells as targets. The responding effector cell displayed a specific cytotoxic effect against target cells of the same H-2 genotype as the stimulating cell population. Killing of syngeneic H-2 cells was not observed, even when the labeled target cells were "innocent bystanders" in cultures where specific target cells were reintroduced. Similar results were found with spleen cells taken from mice sensitized in vivo 7 days earlier. The effector cell was not an adherent cell and was not activated by supernatants from MLR. The supernatants were not cytotoxic by themselves. When concanavalin A or phytohemagglutinin was added to the cytotoxic test system, target and effector cells were agglutinated. Under these conditions, killing of H-2a target cells was observed in mixed cultures where H-2a lymphocytes were also the effector cells. These findings indicate that specifically activated, probably thymus-derived lymphocytes, can kill nonspecifically once they have been activated and providing there is close contact between effector and target cells. Thus, specificity of T cell killing appears to be restricted to recognition and subsequent binding to the targets, the actual effector phase being nonspecific. PMID:4269560

  9. Varied sensitivity to therapy of HIV-1 strains in CD4+ lymphocyte sub-populations upon ART initiation

    Directory of Open Access Journals (Sweden)

    Paxton William A

    2010-12-01

    Full Text Available Abstract Background Although antiretroviral therapy (ART has proven its success against HIV-1, the long lifespan of infected cells and viral latency prevent eradication. In this study we analyzed the sensitivity to ART of HIV-1 strains in naïve, central memory and effector memory CD4+ lymphocyte subsets. Methods From five patients cellular HIV-1 infection levels were quantified before and after initiation of therapy (2-5 weeks. Through sequencing the C2V3 region of the HIV-1 gp120 envelope, we studied the effect of short-term therapy on virus variants derived from naïve, central memory and effector memory CD4+ lymphocyte subsets. Results During short-term ART, HIV-1 infection levels declined in all lymphocyte subsets but not as much as RNA levels in serum. Virus diversity in the naïve and central memory lymphocyte populations remained unchanged, whilst diversity decreased in serum and the effector memory lymphocytes. ART differentially affected the virus populations co-circulating in one individual harboring a dual HIV-1 infection. Changes in V3 charge were found in all individuals after ART initiation with increases within the effector memory subset and decreases found in the naïve cell population. Conclusions During early ART virus diversity is affected mainly in the serum and effector memory cell compartments. Differential alterations in V3 charge were observed between effector memory and naïve populations. While certain cell populations can be targeted preferentially during early ART, some virus strains demonstrate varied sensitivity to therapy, as shown from studying two strains within a dual HIV-1 infected individual.

  10. Cognate antigen stimulation generates potent CD8+ inflammatory effector T cells.

    Directory of Open Access Journals (Sweden)

    Hsueh-Cheng eSung

    2013-12-01

    Full Text Available Inflammatory reactions are believed to be triggered by innate signals and have a major protective role by recruiting innate immunity cells, favoring lymphocyte activation and differentiation, and thus contributing to the sequestration and elimination of the injurious stimuli. Although certain lymphocyte types such as TH17 cells co-participate in inflammatory reactions, their generation from the naïve pool requires the pre-existence of an inflammatory milieu. In this context, inflammation is always regarded as beginning with an innate response that may be eventually perpetuated and amplified by certain lymphocyte types. In contrast, we here show that even in sterile immunizations or in MyD88 deficient mice, CD8 T cells produce a burst of pro-inflammatory cytokines and chemokines. These functions follow opposite rules to the classic CD8 effector functions since they are generated prior to cell expansion and decline before antigen elimination. As few as 56 CD8+ inflammatory effector cells in a lymph node can mobilize 107 cells in 24h, including lymphocytes, natural killer cells and several accessory cell types involved in inflammatory reactions. Thus, although inflammation modulates cognate responses, CD8 cognate responses also initiate local inflammatory reactions.

  11. Effector Regulatory T Cell Differentiation and Immune Homeostasis Depend on the Transcription Factor Myb.

    Science.gov (United States)

    Dias, Sheila; D'Amico, Angela; Cretney, Erika; Liao, Yang; Tellier, Julie; Bruggeman, Christine; Almeida, Francisca F; Leahy, Jamie; Belz, Gabrielle T; Smyth, Gordon K; Shi, Wei; Nutt, Stephen L

    2017-01-17

    FoxP3-expressing regulatory T (Treg) cells are essential for maintaining immune homeostasis. Activated Treg cells undergo further differentiation into an effector state that highly expresses genes critical for Treg cell function, although how this process is coordinated on a transcriptional level is poorly understood. Here, we demonstrate that mice lacking the transcription factor Myb in Treg cells succumbed to a multi-organ inflammatory disease. Myb was specifically expressed in, and required for the differentiation of, thymus-derived effector Treg cells. The combination of transcriptome and genomic footprint analyses revealed that Myb directly regulated a large proportion of the gene expression specific to effector Treg cells, identifying Myb as a critical component of the gene regulatory network controlling effector Treg cell differentiation and function. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Identification and characterization of a lymphocytic Rho-GTPase effector: rhotekin-2

    International Nuclear Information System (INIS)

    Collier, F.M.; Gregorio-King, C.C.; Gough, T.J.; Talbot, C.D.; Walder, K.; Kirkland, M.A.

    2004-01-01

    Rhotekin belongs to the group of proteins containing a Rho-binding domain that are target peptides (effectors) for the Rho-GTPases. We previously identified a novel cDNA with homology to human rhotekin and in this study we cloned and characterized the coding region of this novel 12-exon gene. The ORF encodes a 609 amino-acid protein comprising a Class I Rho-binding domain and pleckstrin homology (PH) domain. Cellular cDNA expression of this new protein, designated Rhotekin-2 (RTKN2), was shown in the cytosol and nucleus of CHO cells. Using bioinformatics and RTPCR we identified three major splice variants, which vary in both the Rho-binding and PH domains. Real-time PCR studies showed exclusive RTKN2 expression in pooled lymphocytes and further purification indicated sole expression in CD4 pos T-cells and bone marrow-derived B-cells. Gene expression was increased in quiescent T-cells but negligible in activated proliferating cells. In malignant samples expression was absent in myeloid leukaemias, low in most B-cell malignancies and CD8 pos T-cell malignancies, but very high in CD4 pos /CD8 pos T-lymphoblastic lymphoma. As the Rho family is critical in lymphocyte development and function, RTKN2 may play an important role in lymphopoiesis

  13. Immunometabolism of lymphocytes and its changes in experimental diabetes mellitus

    Directory of Open Access Journals (Sweden)

    A. M. Kamyshny

    2016-12-01

    Full Text Available Lymphocytes are sensitive to changes in metabolism. Metabolic changes, which develop in conditions of diabetes mellitus, especially hyperglycemia, can directly influence the immunometabolism of lymphocytes. The T cells express a series of glucose transporters, the main of which is the Glut 1. The prodiabetogenic Th1 and Th17-cells that cause insulitis are characterized by high level of expression of Glut 1 and tendency to glycolysis. The suppressor Treg, on the contrary, has the low expression of Glut 1 and the high rate of oxidative metabolism. Purpose of the study: to analyze the contemporary literature and own data, obtained concerning the immunometabolism of lymphocyte and its changes in conditions of diabetes. To determine the role of 6 key metabolic ways that play a crucial role in the differentiation and survival of immune cells: 1 glycolysis; 2 tricarboxylic acid (TCA cycle; 3 pentose-phosphate cycle; 4 fatty acid oxidation; 5 fatty acid synthesis and 6 metabolism of amino acids, each of which have different activity level in specific types of immune cells. Conclusions: different types of immune cells prefer different ways of metabolism. The effector Th1-, Th2-, Th17-cells and М1-macrophages use primarily glycolysis, pentose-phosphate cycle and synthesis of fatty acids, while T-regulatory, CD8+ memory cells and M2-macrophages use the TCA cycle and oxidation of fatty acids. Changes in the metabolism of different amino acids can influence the generation of effector and Treg lymphocytes. The high activity of mTOR can enhance the progression of diabetes by activating the effector proinflammatory subpopulations of lymphocytes, and vice versa, the low activity promotes the differentiation of Treg, blocking the insulitis. In our work we investigated the level of expression of mRNA of genes Glut 1, mTOR and AMPK1α in PLN of rats with experimental streptozotocin-induced diabetes and after metformin introduction and found that the hyperglycemia

  14. Clonal expansion under the microscope: studying lymphocyte activation and differentiation using live-cell imaging.

    Science.gov (United States)

    Polonsky, Michal; Chain, Benjamin; Friedman, Nir

    2016-03-01

    Clonal expansion of lymphocytes is a hallmark of vertebrate adaptive immunity. A small number of precursor cells that recognize a specific antigen proliferate into expanded clones, differentiate and acquire various effector and memory phenotypes, which promote effective immune responses. Recent studies establish a large degree of heterogeneity in the level of expansion and in cell state between and within expanding clones. Studying these processes in vivo, while providing insightful information on the level of heterogeneity, is challenging due to the complex microenvironment and the inability to continuously track individual cells over extended periods of time. Live cell imaging of ex vivo cultures within micro fabricated arrays provides an attractive methodology for studying clonal expansion. These experiments facilitate continuous acquisition of a large number of parameters on cell number, proliferation, death and differentiation state, with single-cell resolution on thousands of expanding clones that grow within controlled environments. Such data can reveal stochastic and instructive mechanisms that contribute to observed heterogeneity and elucidate the sequential order of differentiation events. Intercellular interactions can also be studied within these arrays by following responses of a controlled number of interacting cells, all trapped within the same microwell. Here we describe implementations of live-cell imaging within microwell arrays for studies of lymphocyte clonal expansion, portray insights already gained from these experiments and outline directions for future research. These tools, together with in vivo experiments tracking single-cell responses, will expand our understanding of adaptive immunity and the ways by which it can be manipulated.

  15. CD4+CD25+ regulatory T cells control CD8+ T-cell effector differentiation by modulating IL-2 homeostasis

    Science.gov (United States)

    McNally, Alice; Hill, Geoffrey R.; Sparwasser, Tim; Thomas, Ranjeny; Steptoe, Raymond J.

    2011-01-01

    CD4+CD25+ regulatory T cells (Treg) play a crucial role in the regulation of immune responses. Although many mechanisms of Treg suppression in vitro have been described, the mechanisms by which Treg modulate CD8+ T cell differentiation and effector function in vivo are more poorly defined. It has been proposed, in many instances, that modulation of cytokine homeostasis could be an important mechanism by which Treg regulate adaptive immunity; however, direct experimental evidence is sparse. Here we demonstrate that CD4+CD25+ Treg, by critically regulating IL-2 homeostasis, modulate CD8+ T-cell effector differentiation. Expansion and effector differentiation of CD8+ T cells is promoted by autocrine IL-2 but, by competing for IL-2, Treg limit CD8+ effector differentiation. Furthermore, a regulatory loop exists between Treg and CD8+ effector T cells, where IL-2 produced during CD8+ T-cell effector differentiation promotes Treg expansion. PMID:21502514

  16. Heritability of Susceptibility to Ionizing Radiation-Induced Apoptosis of Human Lymphocyte Subpopulations

    International Nuclear Information System (INIS)

    Schmitz, Annette; Bayer, Jan; Dechamps, Nathalie; Goldin, Lynn; Thomas, Gilles

    2007-01-01

    Purpose: To evaluate the heritability of intrinsic radiosensitivity, the induction of apoptosis in lymphocyte subpopulations was determined on samples from related individuals belonging to large kindred families. Methods and Materials: Quiescent lymphocytes from 334 healthy individuals were gamma-irradiated in vitro. Apoptosis was determined 18 h after irradiation by eight-color flow cytometry. Radiosensitivity was quantified from dose-effect curves. Intrafamilial correlations and heritability were computed for 199 father-mother-offspring trios using the programs SOLAR (Sequential Oligogenic Linkage Analysis Routines) and SAGE (Statistical Analysis for Genetic Epidemiology). Segregation analyses were conducted using SAGE. Results: Marked differential susceptibility of naive and memory T lymphocytes was demonstrated. Also, although age and gender were significant covariates, their effects only accounted for a minor part of the inter-individual variation. Parent-offspring and sib-sib correlations were significant for the radiosensitivity of B cells, T4, and T8 and of effector memory T4 and T8 subpopulations. In the T4-effector memory subpopulation, the phenotype showed correlations most consistent with dominant or additive genetic effects, and the results of the segregation analysis were consistent with the contribution of a bi-allelic dominant locus. Conclusions: Heritability was demonstrated for the susceptibility to ionizing radiation-induced apoptosis of lymphocyte populations, and the segregation of the T4-effector memory radiosensitivity phenotype was consistent with a simple mendelian transmission model involving one major gene

  17. Decreased circulating T regulatory lymphocytes in obese patients undergoing bariatric surgery.

    Science.gov (United States)

    Agabiti-Rosei, Claudia; Trapletti, Valentina; Piantoni, Silvia; Airò, Paolo; Tincani, Angela; De Ciuceis, Carolina; Rossini, Claudia; Mittempergher, Francesco; Titi, Amin; Portolani, Nazario; Caletti, Stefano; Coschignano, Maria Antonietta; Porteri, Enzo; Tiberio, Guido A M; Pileri, Paola; Solaini, Leonardo; Kumar, Rajesh; Ministrini, Silvia; Agabiti Rosei, Enrico; Rizzoni, Damiano

    2018-01-01

    It has been previously demonstrated that T lymphocytes may be involved in the development of hypertension and microvascular remodeling, and that circulating T effector lymphocytes may be increased in hypertension. In particular, Th1 and Th 17 lymphocytes may contribute to the progression of hypertension and microvascular damage while T-regulatory (Treg) lymphocytes seem to be protective in this regard. However, no data is available about patients with severe obesity, in which pronounced microvascular alterations were observed. We have investigated 32 severely obese patients undergoing bariatric surgery, as well as 24 normotensive lean subjects and 12 hypertensive lean subjects undergoing an elective surgical intervention. A peripheral blood sample was obtained before surgery for assessment of CD4+ T lymphocyte subpopulations. Lymphocyte phenotype was evaluated by flow cytometry in order to assess T-effector and Treg lymphocytes. A marked reduction of several Treg subpopulations was observed in obese patients compared with controls, together with an increased in CD4+ effector memory T-effector cells. In severely obese patients, Treg lymphocytes are clearly reduced and CD4+ effector memory cells are increased. It may be hypothesized that they might contribute to the development of marked microvascular alterations previously observed in these patients.

  18. Asymmetric T lymphocyte division in the initiation of adaptive immune responses.

    Science.gov (United States)

    Chang, John T; Palanivel, Vikram R; Kinjyo, Ichiko; Schambach, Felix; Intlekofer, Andrew M; Banerjee, Arnob; Longworth, Sarah A; Vinup, Kristine E; Mrass, Paul; Oliaro, Jane; Killeen, Nigel; Orange, Jordan S; Russell, Sarah M; Weninger, Wolfgang; Reiner, Steven L

    2007-03-23

    A hallmark of mammalian immunity is the heterogeneity of cell fate that exists among pathogen-experienced lymphocytes. We show that a dividing T lymphocyte initially responding to a microbe exhibits unequal partitioning of proteins that mediate signaling, cell fate specification, and asymmetric cell division. Asymmetric segregation of determinants appears to be coordinated by prolonged interaction between the T cell and its antigen-presenting cell before division. Additionally, the first two daughter T cells displayed phenotypic and functional indicators of being differentially fated toward effector and memory lineages. These results suggest a mechanism by which a single lymphocyte can apportion diverse cell fates necessary for adaptive immunity.

  19. Differential Impact of In Vivo CD8+ T Lymphocyte Depletion in Controller versus Progressor Simian Immunodeficiency Virus-Infected Macaques.

    Science.gov (United States)

    Chowdhury, Ankita; Hayes, Timothy L; Bosinger, Steven E; Lawson, Benton O; Vanderford, Thomas; Schmitz, Joern E; Paiardini, Mirko; Betts, Michael; Chahroudi, Ann; Estes, Jacob D; Silvestri, Guido

    2015-09-01

    Numerous studies have demonstrated that CD8(+) T lymphocytes suppress virus replication during human immunodeficiency virus (HIV)/simian immunodeficiency virus (SIV) infection. However, the mechanisms underlying this activity of T cells remain incompletely understood. Here, we conducted CD8(+) T lymphocyte depletion in 15 rhesus macaques (RMs) infected intravenously (i.v.) with SIVmac239. At day 70 postinfection, the animals (10 progressors with high viremia and 5 controllers with low viremia) were CD8 depleted by i.v. administration of the antibody M-T807R1. As expected, CD8 depletion resulted in increased virus replication, more prominently in controllers than progressors, which correlated inversely with predepletion viremia. Of note, the feature of CD8(+) T lymphocyte predepletion that correlated best with the increase in viremia postdepletion was the level of CD8(+) T-bet(+) lymphocytes. We next found that CD8 depletion resulted in a homogenous increase of SIV RNA in superficial and mesenteric lymph nodes, spleen, and the gastrointestinal tract of both controllers and progressors. Interestingly, the level of SIV DNA increased postdepletion in both CD4(+) central memory T lymphocytes (TCM) and CD4(+) effector memory T lymphocytes (TEM) in progressor RMs but decreased in the CD4(+) TCM of 4 out of 5 controllers. Finally, we found that CD8 depletion is associated with a greater increase in CD4(+) T lymphocyte activation (measured by Ki-67 expression) in controllers than in progressors. Overall, these data reveal a differential impact of CD8(+) T lymphocyte depletion between controller and progressor SIV-infected RMs, emphasizing the complexity of the in vivo antiviral role of CD8(+) T lymphocytes. In this study, we further dissect the impact of CD8(+) T lymphocytes on HIV/SIV replication during SIV infection. CD8(+) T lymphocyte depletion leads to a relatively homogenous increase in viral replication in peripheral blood and tissues. CD8(+) T lymphocyte depletion

  20. In vitro sensitization of human lymphocytes to a myeloma cell-related antigen

    International Nuclear Information System (INIS)

    Whitson, M.E.; Griffin, G.D.; Novelli, G.D.; Solomon, A.

    1981-01-01

    Peripheral blood lymphocytes from normal human donors were cocultivated with cells from two established human multiple myeloma cell lines, RPMI 8226 and K-737, and with lymphoblastoid cells from a third B cell line, RAMM. After a comparison of three methods of lymphocyte sensitization, a 6-day incubation protocol with equal numbers of normal lymphocytes and mitomycin C-treated tumor cells was selected. Cells fom the RPMI 8226 myeloma line stimulated the differentiation of lymphocytes into cytotoxic effector cells as measured by 51 Cr release from labeled target cells. The RPMI 8226-sensitized lymphocytes were cytotoxic for myeloma cells (RPMI 8226 and K-737) and for lymphoblastoid cells (RAMM) but not for cells from human lung tumor lines (A549, A427, MB9812), a breast carcinoma line (ALAB), a normal diploid fibroblast line (HSBP), or normal lymphocytes

  1. In vitro sensitization of human lymphocytes to a myeloma cell-related antigen

    Energy Technology Data Exchange (ETDEWEB)

    Whitson, M.E. (Univ. of South Carolina, Columbia); Griffin, G.D.; Novelli, G.D.; Solomon, A.

    1981-01-01

    Peripheral blood lymphocytes from normal human donors were cocultivated with cells from two established human multiple myeloma cell lines, RPMI 8226 and K-737, and with lymphoblastoid cells from a third B cell line, RAMM. After a comparison of three methods of lymphocyte sensitization, a 6-day incubation protocol with equal numbers of normal lymphocytes and mitomycin C-treated tumor cells was selected. Cells fom the RPMI 8226 myeloma line stimulated the differentiation of lymphocytes into cytotoxic effector cells as measured by /sup 51/Cr release from labeled target cells. The RPMI 8226-sensitized lymphocytes were cytotoxic for myeloma cells (RPMI 8226 and K-737) and for lymphoblastoid cells (RAMM) but not for cells from human lung tumor lines (A549, A427, MB9812), a breast carcinoma line (ALAB), a normal diploid fibroblast line (HSBP), or normal lymphocytes.

  2. A molecular threshold for effector CD8(+) T cell differentiation controlled by transcription factors Blimp-1 and T-bet.

    Science.gov (United States)

    Xin, Annie; Masson, Frederick; Liao, Yang; Preston, Simon; Guan, Tianxia; Gloury, Renee; Olshansky, Moshe; Lin, Jian-Xin; Li, Peng; Speed, Terence P; Smyth, Gordon K; Ernst, Matthias; Leonard, Warren J; Pellegrini, Marc; Kaech, Susan M; Nutt, Stephen L; Shi, Wei; Belz, Gabrielle T; Kallies, Axel

    2016-04-01

    T cell responses are guided by cytokines that induce transcriptional regulators, which ultimately control differentiation of effector and memory T cells. However, it is unknown how the activities of these molecular regulators are coordinated and integrated during the differentiation process. Using genetic approaches and transcriptional profiling of antigen-specific CD8(+) T cells, we reveal a common program of effector differentiation that is regulated by IL-2 and IL-12 signaling and the combined activities of the transcriptional regulators Blimp-1 and T-bet. The loss of both T-bet and Blimp-1 leads to abrogated cytotoxic function and ectopic IL-17 production in CD8(+) T cells. Overall, our data reveal two major overlapping pathways of effector differentiation governed by the availability of Blimp-1 and T-bet and suggest a model for cytokine-induced transcriptional changes that combine, quantitatively and qualitatively, to promote robust effector CD8(+) T cell differentiation.

  3. Differential expression gene profiling in human lymphocyte after 6 h irradiated

    International Nuclear Information System (INIS)

    Li Jianguo; Qin Xiujun; Zhang Wei; Xu Chaoqi; Li Weibin; Dang Xuhong; Zuo Yahui

    2011-01-01

    Objective: To provide the evidence of health damage for the staff irradiated from the gene level. Methods: The study analyzed the differential transcriptional profile of normal human lymphocyte and human lymphocyte irradiated with 0.1 Gy, 0.2 Gy, 0.5 Gy, 1.0 Gy by whole genome chip after 6 h irradiated. Results: The results showed that there were 1177 differentially expressed genes with 0.1 Gy after 6 h irradiation, and there were 1922 differentially expressed genes with 0.2 Gy after 6 h irradiation, and there were 492 differentially expressed genes with 0.5 Gy after 6 h irradiation, 2615 differentially expressed genes with 1.0 Gy after 6 h irradiation, 114 differentially expressed genes in 4 dose points after 6 h irradiation. RT-PCR results indicated that the relative quantity's result of EGR1, HLA-DMB and TAIAP1 was consistent with gene chip data. Conclusion: The study found many significant different genes in human lymphocyte with different doses after 6 h irradiation, which will provide a basis for the further radiation-different-genes and the mechanism of radiation damage. (authors)

  4. Migration of allosensitized helper but not cytolytic T-lymphocyte clones is inhibited by prostaglandin E2

    International Nuclear Information System (INIS)

    Jordan, M.L.; Hoffman, R.A.; Simmons, R.L.

    1986-01-01

    The authors have previously reported that random migration of one clone of C57BL/6 anti DBA/2 helper lymphocytes is significantly inhibited by physiologic concentrations of prostaglandin E 2 (PGE 2 ). The present studies were designed to determine if lymphocyte locomotor responses to PGE 2 are dictated by (1) clone effector function and/or (2) the presence of specific cell surface binding sites for PGE 2 . Random locomotion of eight different lymphocyte clones (all C57BL/6 anti DBA/2) was studied in a modified Boyden chamber assay. Clone function was characterized as helper (H, n = 3), cytolytic (C, n = 4) or cytolytic only in the presence of lectin (L, n = 1). Random migration of all H clones was consistently inhibited by PGE 2 . However, none of the clones possessing a lytic mechanism (C or L) were inhibited by even the highest (1000 ng/ml) concentration of PGE 2 tested. Incubation of clones with 3 H-PGE 2 in the presence of excess unlabelled PGE 2 did not demonstrate specific binding of PGE 2 to either H or C clones. The authors conclude that (1) the effects of PGE 2 on lymphocyte random migration are effector function specific and (2) these responses do not appear to be mediated by specialized cell surface receptors for PGE 2 . Subset specific locomotor responses to PGE 2 may constitute a mechanism whereby lymphocytes with distinct effector functions may differentially accumulate at sites of inflammation

  5. Differentiation of human lymphocytes into nuclear vlimata by meiosis. The cytotoxic effect of calcium-activated neutral proteinase inhibitor

    OpenAIRE

    Logothetou-Rella, H.

    1994-01-01

    Phytohaemagglutinin (PHA)-activated lymphocytes differentiated into nuclear vlimata (NVs) in vitro. Lymphocyte attachment was followed by formation and extrusion of cytoplasmic vesicles. nuclear elongation and fragmentation into NVs. NVs and cytoplasmic vesicles were detached and organized into large cell nodules in suspension. Immunocytochemistry showed that T-lymphocytes differentiated mainly to NVs while B-lymphocytes to buds. During differentiation ther...

  6. Allogeneic effector/memory Th-1 cells impair FoxP3+ regulatory T lymphocytes and synergize with chaperone-rich cell lysate vaccine to treat leukemia.

    Science.gov (United States)

    Janikashvili, Nona; LaCasse, Collin J; Larmonier, Claire; Trad, Malika; Herrell, Amanda; Bustamante, Sara; Bonnotte, Bernard; Har-Noy, Michael; Larmonier, Nicolas; Katsanis, Emmanuel

    2011-02-03

    Therapeutic strategies combining the induction of effective antitumor immunity with the inhibition of the mechanisms of tumor-induced immunosuppression represent a key objective in cancer immunotherapy. Herein we demonstrate that effector/memory CD4(+) T helper-1 (Th-1) lymphocytes, in addition to polarizing type-1 antitumor immune responses, impair tumor-induced CD4(+)CD25(+)FoxP3(+) regulatory T lymphocyte (Treg) immunosuppressive function in vitro and in vivo. Th-1 cells also inhibit the generation of FoxP3(+) Tregs from naive CD4(+)CD25(-)FoxP3(-) T cells by an interferon-γ-dependent mechanism. In addition, in an aggressive mouse leukemia model (12B1), Th-1 lymphocytes act synergistically with a chaperone-rich cell lysate (CRCL) vaccine, leading to improved survival and long-lasting protection against leukemia. The combination of CRCL as a source of tumor-specific antigens and Th-1 lymphocytes as an adjuvant has the potential to stimulate efficient specific antitumor immunity while restraining Treg-induced suppression.

  7. Effects of atomic bomb radiation on differentiation of B lymphocytes and on the function of concanavalin A-induced suppressor T lymphocytes

    International Nuclear Information System (INIS)

    Yamada, Y.; Neriishi, S.; Ishimaru, T.; Shimba, N.; Hamilton, H.B.; Ohgushi, Y.; Koyanagi, M.; Ichimaru, M.

    1985-01-01

    The differentiation of peripheral blood B lymphocytes into immunoglobulin-producing cells (Ig-PC) by pokeweed mitogen (PWM) and the function of concanavalin A (Con A)-induced suppressor T lymphocytes were examined to elucidate the late effects of atomic bomb radiation. A total of 140 individuals, 70 with an exposure dose of 100 rad or more and an equal number with an exposure dose of 0 rad matched by sex and age, were selected from the Nagasaki Adult Health Study (AHS) sample. Both the differentiation of peripheral blood B lymphocytes into Ig-PC by PWM and the function of Con A-induced suppressor T lymphocytes tended to be more depressed in the exposed group than in the control group, but a statistically significant difference could not be observed between the two groups. The function of Con A-induced suppressor T lymphocytes tended to decrease with age, but a statistical significance was detected only for percentage suppression against IgM-PC

  8. Comparative reactivity of human IgE to cynomolgus monkey and human effector cells and effects on IgE effector cell potency

    Science.gov (United States)

    Saul, Louise; Saul, Louise; Josephs, Debra H; Josephs, Debra H; Cutler, Keith; Cutler, Keith; Bradwell, Andrew; Bradwell, Andrew; Karagiannis, Panagiotis; Karagiannis, Panagiotis; Selkirk, Chris; Selkirk, Chris; Gould, Hannah J; Gould, Hannah J; Jones, Paul; Jones, Paul; Spicer, James F; Spicer, James F; Karagiannis, Sophia N; Karagiannis, Sophia N

    2014-01-01

    Background: Due to genetic similarities with humans, primates of the macaque genus such as the cynomolgus monkey are often chosen as models for toxicology studies of antibody therapies. IgE therapeutics in development depend upon engagement with the FcεRI and FcεRII receptors on immune effector cells for their function. Only limited knowledge of the primate IgE immune system is available to inform the choice of models for mechanistic and safety evaluations.   Methods: The recognition of human IgE by peripheral blood lymphocytes from cynomolgus monkey and man was compared. We used effector cells from each species in ex vivo affinity, dose-response, antibody-receptor dissociation and potency assays. Results: We report cross-reactivity of human IgE Fc with cynomolgus monkey cells, and comparable binding kinetics to peripheral blood lymphocytes from both species. In competition and dissociation assays, however, human IgE dissociated faster from cynomolgus monkey compared with human effector cells. Differences in association and dissociation kinetics were reflected in effector cell potency assays of IgE-mediated target cell killing, with higher concentrations of human IgE needed to elicit effector response in the cynomolgus monkey system. Additionally, human IgE binding on immune effector cells yielded significantly different cytokine release profiles in each species. Conclusion: These data suggest that human IgE binds with different characteristics to human and cynomolgus monkey IgE effector cells. This is likely to affect the potency of IgE effector functions in these two species, and so has relevance for the selection of biologically-relevant model systems when designing pre-clinical toxicology and functional studies. PMID:24492303

  9. Transcription Factor Networks Directing the Development, Function, and Evolution of Innate Lymphoid Effectors

    Science.gov (United States)

    Kang, Joonsoo; Malhotra, Nidhi

    2015-01-01

    Mammalian lymphoid immunity is mediated by fast and slow responders to pathogens. Fast innate lymphocytes are active within hours after infections in mucosal tissues. Slow adaptive lymphocytes are conventional T and B cells with clonal antigen receptors that function days after pathogen exposure. A transcription factor (TF) regulatory network guiding early T cell development is at the core of effector function diversification in all innate lymphocytes, and the kinetics of immune responses is set by developmental programming. Operational units within the innate lymphoid system are not classified by the types of pathogen-sensing machineries but rather by discrete effector functions programmed by regulatory TF networks. Based on the evolutionary history of TFs of the regulatory networks, fast effectors likely arose earlier in the evolution of animals to fortify body barriers, and in mammals they often develop in fetal ontogeny prior to the establishment of fully competent adaptive immunity. PMID:25650177

  10. Protecting and rescuing the effectors: roles of differentiation and survival in the control of memory T cell development

    Directory of Open Access Journals (Sweden)

    Sema eKurtulus

    2013-01-01

    Full Text Available Vaccines, arguably the single most important intervention in improving human health, have exploited the phenomenon of immunological memory. The elicitation of memory T cells is often an essential part of successful long-lived protective immunity. Our understanding of T cell memory has been greatly aided by the development of TCR Tg mice and MHC tetrameric staining reagents that have allowed the precise tracking of antigen-specific T cell responses. Indeed, following acute infection or immunization, naïve T cells undergo a massive expansion culminating in the generation of a robust effector T cell population. This peak effector response is relatively short-lived and, while most effector T cells die by apoptosis, some remain and develop into memory cells. Although the molecular mechanisms underlying this cell fate decision remain incompletely defined, substantial progress has been made, particularly with regards to CD8+ T cells. For example, the effector CD8+ T cells generated during a response are heterogeneous, consisting of cells with more or less potential to develop into full-fledged memory cells. Development of CD8+ T cell memory is regulated by the transcriptional programs that control the differentiation and survival of effector T cells. While the type of antigenic stimulation and level of inflammation control effector CD8+ T cell differentiation, availability of cytokines and their ability to control expression and function of Bcl-2 family members governs their survival. These distinct differentiation and survival programs may allow for finer therapeutic intervention to control both the quality and quantity of CD8+ T cell memory. Effector to memory transition of CD4+ T cells is less well characterized than CD8+ T cells, emerging details will be discussed. This review will focus on the recent progress made in our understanding of the mechanisms underlying the development of T cell memory with an emphasis on factors controlling survival of

  11. Forced LIGHT expression in prostate tumors overcomes Treg mediated immunosuppression and synergizes with a prostate tumor therapeutic vaccine by recruiting effector T lymphocytes.

    Science.gov (United States)

    Yan, Lisa; Da Silva, Diane M; Verma, Bhavna; Gray, Andrew; Brand, Heike E; Skeate, Joseph G; Porras, Tania B; Kanodia, Shreya; Kast, W Martin

    2015-02-15

    LIGHT, a ligand for lymphotoxin-β receptor (LTβR) and herpes virus entry mediator, is predominantly expressed on activated immune cells and LTβR signaling leads to the recruitment of lymphocytes. The interaction between LIGHT and LTβR has been previously shown to activate immune cells and result in tumor regression in a virally-induced tumor model, but the role of LIGHT in tumor immunosuppression or in a prostate cancer setting, where self antigens exist, has not been explored. We hypothesized that forced expression of LIGHT in prostate tumors would shift the pattern of immune cell infiltration toward an anti-tumoral milieu, would inhibit T regulatory cells (Tregs) and would induce prostate cancer tumor associated antigen (TAA) specific T cells that would eradicate tumors. Real Time PCR was used to evaluate expression of forced LIGHT and other immunoregulatory genes in prostate tumors samples. For in vivo studies, adenovirus encoding murine LIGHT was injected intratumorally into TRAMP-C2 prostate cancer cell tumor bearing mice. Chemokine and cytokine concentrations were determined by multiplex ELISA. Flow cytometry was used to phenotype tumor infiltrating lymphocytes and expression of LIGHT on the tumor cell surface. Tumor-specific lymphocytes were quantified via ELISpot assay. Treg induction and Treg suppression assays determined Treg functionality after LIGHT treatment. LIGHT in combination with a therapeutic vaccine, PSCA TriVax, reduced tumor burden. LIGHT expression peaked within 48 hr of infection, recruited effector T cells that recognized mouse prostate stem cell antigen (PSCA) into the tumor microenvironment, and inhibited infiltration of Tregs. Tregs isolated from tumor draining lymph nodes had impaired suppressive capability after LIGHT treatment. Forced LIGHT treatment combined with PSCA TriVax therapeutic vaccination delays prostate cancer progression in mice by recruiting effector T lymphocytes to the tumor and inhibiting Treg mediated

  12. A Context-Dependent Role for IL-21 in Modulating the Differentiation, Distribution, and Abundance of Effector and Memory CD8 T Cell Subsets.

    Science.gov (United States)

    Tian, Yuan; Cox, Maureen A; Kahan, Shannon M; Ingram, Jennifer T; Bakshi, Rakesh K; Zajac, Allan J

    2016-03-01

    The activation of naive CD8 T cells typically results in the formation of effector cells (TE) as well as phenotypically distinct memory cells that are retained over time. Memory CD8 T cells can be further subdivided into central memory, effector memory (TEM), and tissue-resident memory (TRM) subsets, which cooperate to confer immunological protection. Using mixed bone marrow chimeras and adoptive transfer studies in which CD8 T cells either do or do not express IL-21R, we discovered that under homeostatic or lymphopenic conditions IL-21 acts directly on CD8 T cells to favor the accumulation of TE/TEM populations. The inability to perceive IL-21 signals under competitive conditions also resulted in lower levels of TRM phenotype cells and reduced expression of granzyme B in the small intestine. IL-21 differentially promoted the expression of the chemokine receptor CX3CR1 and the integrin α4β7 on CD8 T cells primed in vitro and on circulating CD8 T cells in the mixed bone marrow chimeras. The requirement for IL-21 to establish CD8 TE/TEM and TRM subsets was overcome by acute lymphocytic choriomeningitis virus infection; nevertheless, memory virus-specific CD8 T cells remained dependent on IL-21 for optimal accumulation in lymphopenic environments. Overall, this study reveals a context-dependent role for IL-21 in sustaining effector phenotype CD8 T cells and influencing their migratory properties, accumulation, and functions. Copyright © 2016 by The American Association of Immunologists, Inc.

  13. Curtailed T-cell activation curbs effector differentiation and generates CD8+ T cells with a naturally-occurring memory stem cell phenotype.

    Science.gov (United States)

    Zanon, Veronica; Pilipow, Karolina; Scamardella, Eloise; De Paoli, Federica; De Simone, Gabriele; Price, David A; Martinez Usatorre, Amaia; Romero, Pedro; Mavilio, Domenico; Roberto, Alessandra; Lugli, Enrico

    2017-09-01

    Human T memory stem (T SCM ) cells with superior persistence capacity and effector functions are emerging as important players in the maintenance of long-lived T-cell memory and are thus considered an attractive population to be used in adoptive transfer-based immunotherapy of cancer. However, the molecular signals regulating their generation remain poorly defined. Here we show that curtailed T-cell receptor stimulation curbs human effector CD8 + T-cell differentiation and allows the generation of CD45RO - CD45RA + CCR7 + CD27 + CD95 + -phenotype cells from highly purified naïve T-cell precursors, resembling naturally-occurring human T SCM . These cells proliferate extensively in vitro and in vivo, express low amounts of effector-associated genes and transcription factors and undergo considerable self-renewal in response to IL-15 while retaining effector differentiation potential. Such a phenotype is associated with a lower number of mitochondria compared to highly-activated effector T cells committed to terminal differentiation. These results shed light on the molecular signals that are required to generate long-lived memory T cells with potential application in adoptive cell transfer immunotherapy. © 2017 The Authors. European Journal of Immunology published by WILEY-VCH Verlag GmbH & Co.KGaA, Weinheim.

  14. Divergent effects of norepinephrine, dopamine and substance P on the activation, differentiation and effector functions of human cytotoxic T lymphocytes

    Directory of Open Access Journals (Sweden)

    Niggemann Bernd

    2009-12-01

    Full Text Available Abstract Background Neurotransmitters are important regulators of the immune system, with very distinct and varying effects on different leukocyte subsets. So far little is known about the impact of signals mediated by neurotransmitters on the function of CD8+ T lymphocytes. Therefore, we investigated the influence of norepinephrine, dopamine and substance P on the key tasks of CD8+ T lymphocytes: activation, migration, extravasation and cytotoxicity. Results The activation of naïve CD8+ T lymphocytes by CD3/CD28 cross-linking was inhibited by norepinephrine and dopamine, which was caused by a downregulation of interleukin (IL-2 expression via Erk1/2 and NF-κB inhibition. Furthermore, all of the investigated neurotransmitters increased the spontaneous migratory activity of naïve CD8+ T lymphocytes with dopamine being the strongest inducer. In contrast, activated CD8+ T lymphocytes showed a reduced migratory activity in the presence of norepinephrine and substance P. With regard to extravasation we found norepinephrine to induce adhesion of activated CD8+ T cells: norepinephrine increased the interleukin-8 release from endothelium, which in turn had effect on the activated CXCR1+ CD8+ T cells. At last, release of cytotoxic granules from activated cells in response to CD3 cross-linking was not influenced by any of the investigated neurotransmitters, as we have analyzed by measuring the β-hexosamidase release. Conclusion Neurotransmitters are specific modulators of CD8+ T lymphocytes not by inducing any new functions, but by fine-tuning their key tasks. The effect can be either stimulatory or suppressive depending on the activation status of the cells.

  15. Radiation effects on lymphocytes

    International Nuclear Information System (INIS)

    Roser, B.

    1976-01-01

    This review of the ontogeny of lymphocyte populations concentrates on sites of production, rates of production, and the factors governing the differentiation and longevity of the various lymphocyte pools. The physiology of the lymphocyte pools is described with particular emphasis on recirculation from blood to lymph through lymphoid tissues. The separate routes of recirculation of both thymus-derived and nonthymus-derived lymphocytes and the possible anatomical sites and mechanisms of lymphocyte cooperation are discussed. Radiation effects on lymphocyte populations are divided into two sections. First, the effects of whole-body irradiation on the total lymphocyte pools are discussed including the differential effects of irradiation on T lymphocytes, B lymphocytes, lymphoblasts, and plasma cells. The differential sensitivity of various types of immune response is correlated, where possible, with the differential sensitivity of the lymphocyte types involved. Second, experimental attempts to selectively deplete discrete subpopulations of the total lymphocyte pools, e.g., recirculating cells, are briefly discussed with particular emphasis on studies on the effects of the localization of radionuclides in lymphoid tissue

  16. The death effector domains of caspase-8 induce terminal differentiation.

    Directory of Open Access Journals (Sweden)

    Ainhoa Mielgo

    2009-11-01

    Full Text Available The differentiation and senescence programs of metazoans play key roles in regulating normal development and preventing aberrant cell proliferation, such as cancer. These programs are intimately associated with both the mitotic and apoptotic pathways. Caspase-8 is an apical apoptotic initiator that has recently been appreciated to coordinate non-apoptotic roles in the cell. Most of these functions are attributed to the catalytic domain, however, the amino-terminal death effector domains (DEDs, which belong to the death domain superfamily of proteins, can also play key roles during development. Here we describe a novel role for caspase-8 DEDs in regulating cell differentiation and senescence. Caspase-8 DEDs accumulate during terminal differentiation and senescence of epithelial, endothelial and myeloid cells; genetic deletion or shRNA suppression of caspase-8 disrupts cell differentiation, while re-expression of DEDs rescues this phenotype. Among caspase-8 deficient neuroblastoma cells, DED expression attenuated tumor growth in vivo and proliferation in vitro via disruption of mitosis and cytokinesis, resulting in upregulation of p53 and induction of differentiation markers. These events occur independent of caspase-8 catalytic activity, but require a critical lysine (K156 in a microtubule-binding motif in the second DED domain. The results demonstrate a new function for the DEDs of caspase-8, and describe an unexpected mechanism that contributes to cell differentiation and senescence.

  17. B-lymphocytes as key players in chemical-induced asthma.

    Directory of Open Access Journals (Sweden)

    Vanessa De Vooght

    Full Text Available T-lymphocytes and B-lymphocytes are key players in allergic asthma, with B-lymphocytes producing antigen-specific immunoglobulins E (IgE. We used a mouse model of chemical-induced asthma and transferred B-lymphocytes from sensitized animals into naïve wild type mice, B-lymphocyte knock-out (B-KO mice or severe combined immunodeficiency (SCID mice. On days 1 and 8, BALB/c mice were dermally sensitized with 0.3% toluene diisocyanate (TDI (20 µl/ear. On day 15, mice were euthanized and the auricular lymph nodes isolated. B-lymphocytes (CD19(+ were separated from the whole cell suspension and 175,000 cells were injected in the tail vein of naïve wild type, B-KO or SCID mice. Three days later, the mice received a single oropharyngeal challenge with 0.01% TDI (20 µl or vehicle (acetone/olive oil (AOO (controls. Airway reactivity to methacholine and total and differential cell counts in the bronchoalveolar lavage (BAL fluid were measured 24 hours after challenge. B-lymphocytes of AOO or TDI-sensitized mice were characterized for the expression of surface markers and production of cytokines. We found that transfer of B-cells obtained from mice dermally sensitized to toluene diisocyanate (TDI into naïve wild type mice, B-KO mice or SCID mice led, within three days, to an acute asthma-like phenotype after an airway challenge with TDI. This response was specific and independent of IgE. These B-lymphocytes showed antigen presenting capacities (CD80/CD86 and CD40 and consisted of B effector (Be2- (IL-4 and Be1-lymphocytes (IFN-γ. The transferred B-lymphocytes were visualized near large airways, 24 hours after TDI challenge. Thus, B-lymphocytes can provoke an asthmatic response without the action of T-lymphocytes and without major involvement of IgE.

  18. Changes in total and differential white cell counts, total lymphocyte ...

    African Journals Online (AJOL)

    Background: Published reports on the possible changes in the various immune cell populations, especially the total lymphocyte and CD4 cell counts, during the menstrual cycle in Nigerian female subjects are relatively scarce. Aim: To determine possible changes in the total and differential white blood cell [WBC] counts, ...

  19. Immune response to uv-induced tumors: transplantation immunity and lymphocyte populations exhibiting anti-tumor activity

    International Nuclear Information System (INIS)

    Streeter, P.R.

    1985-01-01

    Ultraviolet light-induced murine skin tumors were analyzed for their ability to induce tumor-specific and cross-protective transplantation immunity in immunocompetent syngeneic mice. These studies revealed that progressor UV-tumors, like regressor UV-tumors, possess tumor-specific transplantation antigens. Cross-protective transplantation immunity to UV-tumors, however, was associated with sensitization to the serum used to culture the tumor lines rather than to cross-reactive or common determinants on UV-tumors. An analysis of the cytolytic activity of lymphocytes from the spleens of mice immunized with either regressor or progressor UV-tumors revealed a striking difference between the two immune splenocyte populations. From regressor tumor-immune animals, cytolytic T (Tc) lymphocytes with specificity for the immunizing tumor were found. However, the analysis of splenic lymphocytes from progressor tumor immune animals revealed no such effector cells. To more effectively examine those lymphocytes exhibiting cytolytic activity in vitro, T lymphocyte cloning technology was used as a means of isolating homogeneous lymphocyte populations with the effector activities described above. The mechanisms where NK cells and other nonspecific effector cells could be induced in tumor-immune animals are discussed in the context of class II restricted immune responses

  20. Concanavalin A-induced activation of lymphocytic choriomeningitis virus memory lymphocytes into specifically cytotoxic T cells

    DEFF Research Database (Denmark)

    Marker, O; Thomsen, Allan Randrup; Andersen, G T

    1977-01-01

    When spleen cells, which have been primed to Lymphocytic Choriomeningitis (LCM) virus during a primary infection several months previously, are stimulated in vitro with Con A. highly specific secondary cytotoxic effector cells are generated. The degree of cytotoxicity revealed by such Con A...

  1. Effector T-cells are expanded in systemic lupus erythematosus patients with high disease activity and damage indexes.

    Science.gov (United States)

    Piantoni, S; Regola, F; Zanola, A; Andreoli, L; Dall'Ara, F; Tincani, A; Airo', P

    2018-01-01

    Background and objectives T-cell activation may be one of the pathogenic mechanisms of systemic lupus erythematosus (SLE). After repeated antigenic stimulation, T-cells undergo different modifications, leading to the differentiation into effector memory T-cells (CCR7-CD45RA-) and terminally differentiated effector memory (TDEM) T-cells (CCR7-CD45RA+). Similarly, down-modulation of CD28 may lead to the expansion of the CD28- T-cells, a subpopulation with peculiar effector activities. The aim of this study was the characterization of T-cell phenotype in a cohort of patients with SLE according to disease activity and damage index. Materials and methods Phenotypic analysis of peripheral blood T lymphocytes of 51 SLE patients and 21 healthy controls was done by flow-cytometry. SLE disease activity was evaluated by SLE Disease Activity Index-2000 (SLEDAI-2K) and damage by the Systemic Lupus International Collaborating Clinics/American College of Rheumatology damage index (SDI). The variations between different groups were evaluated by Mann-Whitney test. Bonferroni correction was applied to adjust for multiple comparisons ( p adj ). Spearman rank test was used to evaluate the correlations between quantitative variables. Results CD4+ lymphopenia was found among SLE patients. Patients showed a trend for a higher percentage of TDEM among the CD4+ T-cell subpopulation in comparison with healthy controls ( p = .04). SLE patients were divided into two groups according to disease activity: patients with SLEDAI-2K ≥ 6 ( n = 13) had a higher percentage of circulating CD4+ T-cells with CD28- phenotype ( p adj  = .005) as well as those with an effector memory ( p adj  = .004) and TDEM ( p adj  = .002) phenotype and a trend of decrease of regulatory T-cells (TREGs) ( p = .02), in comparison with patients with low disease activity ( n = 38). Patients with damage (SDI ≥ 1) tended to show an expansion of TDEM among CD4+ T-cells as compared with

  2. Radiosensitivities of sensitized lymphocytes

    International Nuclear Information System (INIS)

    Taniguchi, Kazuto

    1979-01-01

    Immunization of mice with cell antigens such as allogeneic tumor cells or xenogeneic erythrocytes raises a variety of immune reactions mediated by T lymphocytes: i.e. delayed type hypersensitivity (DTH), cytotoxicity, and antibody production. The radiosensitivities of these reactions were examined in mice exposed to 600 R x-irradiation a few hours before or after immunization. 1) DTH to xenogeneic erythrocytes, as demonstrated by footpad reaction, was not suppressed by irradiation 3 h before or after immunization. DTH to allogeneic tumor cells, as demonstrated by a migration inhibition test, hardly developed in mice that had been irradiated before or after immunization. It may have belonged to distinct types of delayed reactions which were mediated by distinct subpopulations of T lymphocytes. 2) Cytotoxicity against allogeneic cells and xenogeneic erythrocytes showed almost the same radiosensitivity. It was scarcely detected in mice that had been irradiated before immunization. However, a low but definite degree of cytotoxicity was detected in mice that had been irradiated only a few hours after immunization. Solubilized allogeneic cells instead of native cells were used as immunizing antigens. It was also possible for precursor cells with cytotoxicity to acquire a radioresistant nature by immunization of solubilized antigens, but native cells were required as stimulation for radioresistant precursor cells to differentiated into nature cytotoxic effector cells. 3) Antibody production against xenogeneic erythrocytes or allogeneic cells was almost completely depleted in mice that had been irradiated before or after immunization. It is possible that antibody production essentially requires cell division and clonal expansion of B lymphocytes. (Bell, E.)

  3. Developmental exposure to 2,3,7,8 tetrachlorodibenzo-p-dioxin attenuates capacity of hematopoietic stem cells to undergo lymphocyte differentiation

    International Nuclear Information System (INIS)

    Ahrenhoerster, Lori S.; Tate, Everett R.; Lakatos, Peter A.; Wang, Xuexia; Laiosa, Michael D.

    2014-01-01

    The process of hematopoiesis, characterized by long-term self-renewal and multi-potent lineage differentiation, has been shown to be regulated in part by the ligand-activated transcription factor known as the aryl hydrocarbon receptor (AHR). 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), a ubiquitous contaminant and the most potent AHR agonist, also modulates regulation of adult hematopoietic stem and progenitor cell (HSC/HPC) homeostasis. However, the effect of developmental TCDD exposure on early life hematopoiesis has not been fully explored. Given the inhibitory effects of TCDD on hematopoiesis and lymphocyte development, we hypothesized that in utero exposure to TCDD would alter the functional capacity of fetal HSC/HPCs to complete lymphocyte differentiation. To test this hypothesis, we employed a co-culture system designed to facilitate the maturation of progenitor cells to either B or T lymphocytes. Furthermore, we utilized an innovative limiting dilution assay to precisely quantify differences in lymphocyte differentiation between HSC/HPCs obtained from fetuses of dams exposed to 3 μg/kg TCDD or control. We found that the AHR is transcribed in yolk sac hematopoietic cells and is transcriptionally active as early as gestational day (GD) 7.5. Furthermore, the number of HSC/HPCs present in the fetal liver on GD 14.5 was significantly increased in fetuses whose mothers were exposed to TCDD throughout pregnancy. Despite this increase in HSC/HPC cell number, B and T lymphocyte differentiation is decreased by approximately 2.5 fold. These findings demonstrate that inappropriate developmental AHR activation in HSC/HPCs adversely impacts lymphocyte differentiation and may have consequences for lymphocyte development in the bone marrow and thymus later in life

  4. Developmental exposure to 2,3,7,8 tetrachlorodibenzo-p-dioxin attenuates capacity of hematopoietic stem cells to undergo lymphocyte differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Ahrenhoerster, Lori S.; Tate, Everett R.; Lakatos, Peter A. [Joseph J. Zilber School of Public Health, University of Wisconsin-Milwaukee (United States); Program in Environmental and Occupational Health, Milwaukee, WI 53211 (United States); Wang, Xuexia [Joseph J. Zilber School of Public Health, University of Wisconsin-Milwaukee (United States); Program in Biostatistics, Milwaukee, WI 53211 (United States); Laiosa, Michael D., E-mail: laiosa@uwm.edu [Joseph J. Zilber School of Public Health, University of Wisconsin-Milwaukee (United States); Program in Environmental and Occupational Health, Milwaukee, WI 53211 (United States)

    2014-06-01

    The process of hematopoiesis, characterized by long-term self-renewal and multi-potent lineage differentiation, has been shown to be regulated in part by the ligand-activated transcription factor known as the aryl hydrocarbon receptor (AHR). 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), a ubiquitous contaminant and the most potent AHR agonist, also modulates regulation of adult hematopoietic stem and progenitor cell (HSC/HPC) homeostasis. However, the effect of developmental TCDD exposure on early life hematopoiesis has not been fully explored. Given the inhibitory effects of TCDD on hematopoiesis and lymphocyte development, we hypothesized that in utero exposure to TCDD would alter the functional capacity of fetal HSC/HPCs to complete lymphocyte differentiation. To test this hypothesis, we employed a co-culture system designed to facilitate the maturation of progenitor cells to either B or T lymphocytes. Furthermore, we utilized an innovative limiting dilution assay to precisely quantify differences in lymphocyte differentiation between HSC/HPCs obtained from fetuses of dams exposed to 3 μg/kg TCDD or control. We found that the AHR is transcribed in yolk sac hematopoietic cells and is transcriptionally active as early as gestational day (GD) 7.5. Furthermore, the number of HSC/HPCs present in the fetal liver on GD 14.5 was significantly increased in fetuses whose mothers were exposed to TCDD throughout pregnancy. Despite this increase in HSC/HPC cell number, B and T lymphocyte differentiation is decreased by approximately 2.5 fold. These findings demonstrate that inappropriate developmental AHR activation in HSC/HPCs adversely impacts lymphocyte differentiation and may have consequences for lymphocyte development in the bone marrow and thymus later in life.

  5. Evolution and phylogeny of B lymphocytes

    Directory of Open Access Journals (Sweden)

    Fabiola Claudio-Piedras

    2016-05-01

    Full Text Available B lymphocytes are one of the most important cell types involved in the immune response of mammals. The origin and evolution of this cellular type is unknown, but the B lymphocyte bona fide appeared first in fish. In this review we analize the principal components of the immune response of invertebrates, their phylogenetic distribution and the permancence of some properties that allowed the emergence of the B lymphocyte. We started from the idea that many of the components that characterize the B lymphocyte are found distributed among the invertebrates, however, it is in the B lymphocyte, where all these components that give this type of cell its identity, converged. The actual knowledge we have in regards of the lymphocytes comes, in the most part, from physiological studies in mammals, being the mice the more representative. The origin of the B lymphocyte, its alternative mechanisms for generating receptor diversity, its immune effector response, and the generation of memory, require an evolutionary and multidisiplinary approach for its study.

  6. EFFECTS OF γс-CYTOKINES (IL-2, IL-7 AND IL-15 UPON IN VITRO MATURATION AND DIFFERENTIATION OF CD4+CD45RО+/CD8+CD45RО+ T CELLS

    Directory of Open Access Journals (Sweden)

    K. A. Yurova

    2018-01-01

    Full Text Available Effect of γс-cytokines (IL-2, IL-7 и IL-15 upon maturation and differentiation of cytotoxic and helper CD45RО+ Tcell population was studied in the homeostatic in vitro culture conditions. We have found that IL-2, IL-7 and IL-15 mediate maturation and differentiation of CD8 T cells central memory, replenishing the population of cells that exhibit effector functions. Action of IL-2 on CD4+ central memory T cells is accociated with generation of effector memory cells by reducing the number of immature effectors (CD62L–CD27+, whereas IL-7 promotes the formation of immature (CD62L–CD27+ effectors. IL-2, IL-7 and IL-15 initiate formation of terminally-differentiated cells in a subpopulation of CD8+CD45RO+ lymphocytes, providing a stable immunological memory to a pathogen reinfestation. 

  7. EFFECTS OF γс-CYTOKINES (IL-2, IL-7 AND IL-15 UPON IN VITRO MATURATION AND DIFFERENTIATION OF CD4+CD45RО+/CD8+CD45RО+ T CELLS

    Directory of Open Access Journals (Sweden)

    K. A. Yurova

    2018-01-01

    Full Text Available Effect of γс-cytokines (IL-2, IL-7 и IL-15 upon maturation and differentiation of cytotoxic and helper CD45RО+ Tcell population was studied in the homeostatic in vitro culture conditions. We have found that IL-2, IL-7 and IL-15 mediate maturation and differentiation of CD8 T cells central memory, replenishing the population of cells that exhibit effector functions. Action of IL-2 on CD4+ central memory T cells is accociated with generation of effector memory cells by reducing the number of immature effectors (CD62L–CD27+, whereas IL-7 promotes the formation of immature (CD62L–CD27+ effectors. IL-2, IL-7 and IL-15 initiate formation of terminally-differentiated cells in a subpopulation of CD8+CD45RO+ lymphocytes, providing a stable immunological memory to a pathogen reinfestation.

  8. Crosstalk between T lymphocytes and dendritic cells.

    Science.gov (United States)

    Hivroz, Claire; Chemin, Karine; Tourret, Marie; Bohineust, Armelle

    2012-01-01

    Dendritic cells (DCs) are professional antigen-presenting cells (APCs) with the unique property of inducing priming and differentiation of naïve CD4+ and CD8+ T cells into helper and cytotoxic effectors. Their efficiency is due to their unique ability to process antigen, express costimulatory molecules, secrete cytokines, and migrate to tissues or lymphoid organs to prime T cells. DCs also play an important role in T-cell peripheral tolerance. There is ample evidence that the DC ability to present antigens is regulated by CD4+ helper T cells. Indeed, interactions between surface receptors and ligands expressed respectively by T cells and DCs, as well as T-cell-derived cytokines modify DC functions. This T-cell-induced modification of DCs has been called "education" or "licensing." This intimate crosstalk between DCs and T lymphocytes is key in establishing appropriate adaptive immune responses. It requires cognate interactions between T lymphocytes and DCs, which are organized in time and space by structures called immunological synapses. Here we discuss the particular aspects of immunological synapses formed between T cells and DCs and the role these organized interactions have in T-cell-DC crosstalk.

  9. Quantification of newly produced B and T lymphocytes in untreated chronic lymphocytic leukemia patients

    Directory of Open Access Journals (Sweden)

    Caimi Luigi

    2010-11-01

    Full Text Available Abstract Background The immune defects occurring in chronic lymphocytic leukemia are responsible for the frequent occurrence of infections and autoimmune phenomena, and may be involved in the initiation and maintenance of the malignant clone. Here, we evaluated the quantitative defects of newly produced B and T lymphocytes. Methods The output of B and T lymphocytes from the production and maturation sites was analyzed in chronic lymphocytic leukemia patients and healthy controls by quantifying kappa-deleting recombination excision circles (KRECs and T-cell receptor excision circles (TRECs by a Real-Time PCR assay that simultaneously detects both targets. T-lymphocyte subsets were analyzed by six-color flow cytometric analysis. Data comparison was performed by two-sided Mann-Whitney test. Results KRECs level was reduced in untreated chronic lymphocytic leukemia patients studied at the very early stage of the disease, whereas the release of TRECs+ cells was preserved. Furthermore, the observed increase of CD4+ lymphocytes could be ascribed to the accumulation of CD4+ cells with effector memory phenotype. Conclusions The decreased number of newly produced B lymphocytes in these patients is likely related to a homeostatic mechanism by which the immune system balances the abnormal B-cell expansion. This feature may precede the profound defect of humoral immunity characterizing the later stages of the disease.

  10. Demonstration of NK cell-mediated lysis of varicella-zoster virus (VZV)-infected cells: characterization of the effector cells

    Energy Technology Data Exchange (ETDEWEB)

    Tilden, A.B.; Cauda, R.; Grossi, C.E.; Balch, C.M.; Lakeman, A.D.; Whitley, R.J.

    1986-06-01

    Infection with varicella-zoster virus (VZV) rendered RAJI cells more susceptible to lysis by non-adherent blood lymphocytes. At an effector to target ratio of 80:1 the mean percentage of /sup 51/Cr release of VZV-infected RAJI cells was 41 +/- 12%, whereas that of uninfected RAJI cells was 15 +/- 6%. The increased susceptibility to lysis was associated with increased effector to target conjugate formation in immunofluorescence binding assays. The effector cells cytotoxic for VZV-infected RAJI cells were predominantly Leu-11a/sup +/ Leu-4/sup -/ granular lymphocytes as demonstrated by fluorescence-activated cell sorting. The effector cell active against VZV-infected RAJI cells appeared similar to those active against herpes simplex virus (HSV)-infected cells, because in cold target competition experiments the lysis of /sup 51/Cr-labeled VZV-infected RAJI cells was efficiently inhibited by either unlabeled VZV-infected RAJI cells (mean 71% inhibition, 2:1 ratio unlabeled to labeled target) or HSV-infected RAJI cells (mean 69% inhibition) but not by uninfected RAJI cells (mean 10% inhibition). In contrast, competition experiments revealed donor heterogeneity in the overlap between effector cells for VZV- or HSV-infected RAJI vs K-562 cells.

  11. ER-mitochondria contacts control surface glycan expression and sensitivity to killer lymphocytes in glioma stem-like cells.

    Science.gov (United States)

    Bassoy, Esen Yonca; Kasahara, Atsuko; Chiusolo, Valentina; Jacquemin, Guillaume; Boydell, Emma; Zamorano, Sebastian; Riccadonna, Cristina; Pellegatta, Serena; Hulo, Nicolas; Dutoit, Valérie; Derouazi, Madiha; Dietrich, Pierre Yves; Walker, Paul R; Martinvalet, Denis

    2017-06-01

    Glioblastoma is a highly heterogeneous aggressive primary brain tumor, with the glioma stem-like cells (GSC) being more sensitive to cytotoxic lymphocyte-mediated killing than glioma differentiated cells (GDC). However, the mechanism behind this higher sensitivity is unclear. Here, we found that the mitochondrial morphology of GSCs modulates the ER-mitochondria contacts that regulate the surface expression of sialylated glycans and their recognition by cytotoxic T lymphocytes and natural killer cells. GSCs displayed diminished ER-mitochondria contacts compared to GDCs. Forced ER-mitochondria contacts in GSCs increased their cell surface expression of sialylated glycans and reduced their susceptibility to cytotoxic lymphocytes. Therefore, mitochondrial morphology and dynamism dictate the ER-mitochondria contacts in order to regulate the surface expression of certain glycans and thus play a role in GSC recognition and elimination by immune effector cells. Targeting the mitochondrial morphology, dynamism, and contacts with the ER could be an innovative strategy to deplete the cancer stem cell compartment to successfully treat glioblastoma. © 2017 The Authors.

  12. Measurement of exercise-induced oxidative stress in lymphocytes.

    Science.gov (United States)

    Turner, James E; Bosch, Jos A; Aldred, Sarah

    2011-10-01

    Vigorous exercise is associated with oxidative stress, a state that involves modifications to bodily molecules due to release of pro-oxidant species. Assessment of such modifications provides non-specific measures of oxidative stress in human tissues and blood, including circulating lymphocytes. Lymphocytes are a very heterogeneous group of white blood cells, consisting of subtypes that have different functions in immunity. Importantly, exercise drastically changes the lymphocyte composition in blood by increasing the numbers of some subsets, while leaving other cells unaffected. This fact may imply that observed changes in oxidative stress markers are confounded by changes in lymphocyte composition. For example, lymphocyte subsets may differ in exposure to oxidative stress because of subset differences in cell division and the acquisition of cytotoxic effector functions. The aim of the present review is to raise awareness of interpretational issues related to the assessment of oxidative stress in lymphocytes with exercise and to address the relevance of lymphocyte subset phenotyping in these contexts.

  13. Specialities of the differentiation conditions for the memory cells - either initial or enriched secondary cytotoxic T lymphocyte precursors (pCTL-2) specific to the MHC molecule class 1

    International Nuclear Information System (INIS)

    Brondz, B.D.; Osipova, T.V.; Aptikaeva, G.F.; Kronin, V.V.

    1989-01-01

    The in vivo induced pCTL-2 with phenotype L3T4 - Lyt2 + , specific to the H-2K b molecule, turn into effector CTLs during 4 days in the mixed lymphocyte culture (with heat-treated donor stimulators) much more efficiency when donor and recipient are different from one another not only in MHC class 1 (anti-BIO, MBR BIO.AKM) but in 1+2 (K b +1 b ) anti-C57BL/6 BIAD2(R1O1). The initial pCTL-2 differentiation in enhanced as a result of synergistic effect between the K b alloantigen and rIL2. The anti-K b pCTL-2, being separated from helper T cells by means of absorption onto the macrophage donor monolayer and elution from it, give rise to pronounced differentiation in simplified conditions, irrespective of the stimulator presence and without external rIL2. It is supposed that these phenomena are roused to secrection of the CTL differentiation factor by the eluted pCTL-2 themselves, and besides, rIL2 may promote for secretion of this factor additionally

  14. DEEP--a tool for differential expression effector prediction.

    Science.gov (United States)

    Degenhardt, Jost; Haubrock, Martin; Dönitz, Jürgen; Wingender, Edgar; Crass, Torsten

    2007-07-01

    expressed or not--may play pivotal roles in the tissues or conditions under examination. The described method has been implemented in Java as a client/server application and a web interface called DEEP (Differential Expression Effector Prediction). The client, which features an easy-to-use graphical interface, can freely be downloaded from the following URL: http://deep.bioinf.med.uni-goettingen.de.

  15. Ubiquitin specific protease 21 is dispensable for normal development, hematopoiesis and lymphocyte differentiation.

    Directory of Open Access Journals (Sweden)

    Jaspreet Pannu

    Full Text Available USP21 is a ubiquitin specific protease that catalyzes protein deubiquitination, however the identification of its physiological substrates remains challenging. USP21 is known to deubiquitinate transcription factor GATA3 and death-domain kinase RIPK1 in vitro, however the in vivo settings where this regulation plays a biologically significant role remain unknown. In order to determine whether USP21 is an essential and non-redundant regulator of GATA3 or RIPK1 activity in vivo, we characterized Usp21-deficient mice, focusing on mouse viability and development, hematopoietic stem cell function, and lymphocyte differentiation. The Usp21-knockout mice were found to be viable and fertile, with no significant dysmorphology, in contrast to the GATA3 and RIPK1 knockout lines that exhibit embryonic or perinatal lethality. Loss of USP21 also had no effect on hematopoietic stem cell function, lymphocyte development, or the responses of antigen presenting cells to TLR and TNFR stimulation. GATA3 levels in hematopoietic stem cells or T lymphocytes remained unchanged. We observed that aged Usp21-knockout mice exhibited spontaneous T cell activation, however this was not linked to altered GATA3 levels in the affected cells. The contrast in the phenotype of the Usp21-knockout line with the previously characterized GATA3 and RIPK1 knockout mice strongly indicates that USP21 is redundant for the regulation of GATA3 and RIPK1 activity during mouse development, in hematopoietic stem cells, and in lymphocyte differentiation. The Usp21-deficient mouse line characterized in this study may serve as a useful tool for the future characterization of USP21 physiological functions.

  16. Persistent expansion of CD4(+) effector memory T cells in Wegener's granulomatosis

    NARCIS (Netherlands)

    Abdulahad, W. H.; van der Geld, Y. M.; Stegeman, C. A.; Kallenberg, C. G. M.

    In order to test the hypothesis that Wegener's granulomatosis (WG) is associated with an ongoing immune effector response, even in remission, we examined the distribution of peripheral naive and memory T-lymphocytes in this disease, and analyzed the function-related phenotypes of the memory T-cell

  17. Beyond differential expression: the quest for causal mutations and effector molecules

    Directory of Open Access Journals (Sweden)

    Hudson Nicholas J

    2012-07-01

    Full Text Available Abstract High throughput gene expression technologies are a popular choice for researchers seeking molecular or systems-level explanations of biological phenomena. Nevertheless, there has been a groundswell of opinion that these approaches have not lived up to the hype because the interpretation of the data has lagged behind its generation. In our view a major problem has been an over-reliance on isolated lists of differentially expressed (DE genes which – by simply comparing genes to themselves – have the pitfall of taking molecular information out of context. Numerous scientists have emphasised the need for better context. This can be achieved through holistic measurements of differential connectivity in addition to, or in replacement, of DE. However, many scientists continue to use isolated lists of DE genes as the major source of input data for common readily available analytical tools. Focussing this opinion article on our own research in skeletal muscle, we outline our resolutions to these problems – particularly a universally powerful way of quantifying differential connectivity. With a well designed experiment, it is now possible to use gene expression to identify causal mutations and the other major effector molecules with whom they cooperate, irrespective of whether they themselves are DE. We explain why, for various reasons, no other currently available experimental techniques or quantitative analyses are capable of reaching these conclusions.

  18. α4β7+ CD4+ Effector/Effector Memory T Cells Differentiate into Productively and Latently Infected Central Memory T Cells by Transforming Growth Factor β1 during HIV-1 Infection.

    Science.gov (United States)

    Cheung, Ka-Wai; Wu, Tongjin; Ho, Sai Fan; Wong, Yik Chun; Liu, Li; Wang, Hui; Chen, Zhiwei

    2018-04-15

    HIV-1 transmission occurs mainly through mucosal tissues. During mucosal transmission, HIV-1 preferentially infects α 4 β 7 + gut-homing CCR7 - CD4 + effector/effector memory T cells (T EM ) and results in massive depletion of these cells and other subsets of T EM in gut-associated lymphoid tissues. However, besides being eliminated by HIV-1, the role of T EM during the early stage of infection remains inconclusive. Here, using in vitro -induced α 4 β 7 + gut-homing T EM (α 4 β 7 + T EM ), we found that α 4 β 7 + T EM differentiated into CCR7 + CD4 + central memory T cells (T CM ). This differentiation was HIV-1 independent but was inhibited by SB431542, a specific transforming growth factor β (TGF-β) receptor I kinase inhibitor. Consistently, T EM -to-T CM differentiation was observed in α 4 β 7 + T EM stimulated with TGF-β1 (TGF-β). The T CM properties of the TGF-β-induced T EM -derived T CM (α 4 β 7 + T CM ) were confirmed by their enhanced CCL19 chemotaxis and the downregulation of surface CCR7 upon T cell activation in vitro Importantly, the effect of TGF-β on T CM differentiation also held in T EM directly isolated from peripheral blood. To investigate the significance of the TGF-β-dependent T EM -to-T CM differentiation in HIV/AIDS pathogenesis, we observed that both productively and latently infected α 4 β 7 + T CM could differentiate from α 4 β 7 + T EM in the presence of TGF-β during HIV-1 infection. Collectively, this study not only provides a new insight for the plasticity of T EM but also suggests that the TGF-β-dependent T EM -to-T CM differentiation is a previously unrecognized mechanism for the formation of latently infected T CM after HIV-1 infection. IMPORTANCE HIV-1 is the causative agent of HIV/AIDS, which has led to millions of deaths in the past 30 years. Although the implementation of highly active antiretroviral therapy has remarkably reduced the HIV-1-related morbidity and mortality, HIV-1 is not eradicated in

  19. Chromatin degradation under the effect of differentiation inductors and γ-radiation on thymus lymphocytes in vitro

    International Nuclear Information System (INIS)

    Soldatenkov, V.A.; Sorokina, N.I.; Filippovich, I.V.

    1985-01-01

    Chemical inductors of differentiation were shown to cause chromatin degradation in thymus lymphocytes. This process was prevented by the protein synthesis inhibitors. The fragments formed after the effect of chemical differentiation inductors on thymocytes were fully identical to chromatin internucleosome degradation products formed in the exposed cells. Chromatin degradation under the effect of chemical differentiation inductors was most pronounced in a more radiosensitive thymocyte fraction

  20. The Role of CD39 in Modulating Effector Immune Responses in Inflammatory Bowel Disease

    OpenAIRE

    Huang, Huang

    2015-01-01

    Inflammatory bowel disease is associated with excessive inflammation of the bowel and intestinal tissues in genetically susceptible individuals. IBD can manifest in two major forms, ulcerative colitis and Crohn’s disease. T helper type 17 cells (Th17) are effector lymphocytes that have been linked to intestinal inflammation in both mice and humans. Effector Th17 cells and regulatory T cells (Treg) – a subset pivotal to immune-tolerance maintenance – derive from the same CD4 progenitors. Our i...

  1. Dynamics of Lymphocyte Populations during Trypanosoma cruzi Infection: From Thymocyte Depletion to Differential Cell Expansion/Contraction in Peripheral Lymphoid Organs

    Directory of Open Access Journals (Sweden)

    Alexandre Morrot

    2012-01-01

    Full Text Available The comprehension of the immune responses in infectious diseases is crucial for developing novel therapeutic strategies. Here, we review current findings on the dynamics of lymphocyte subpopulations following experimental acute infection by Trypanosoma cruzi, the causative agent of Chagas disease. In the thymus, although the negative selection process of the T-cell repertoire remains operational, there is a massive thymocyte depletion and abnormal release of immature CD4+CD8+ cells to peripheral lymphoid organs, where they acquire an activated phenotype similar to activated effector or memory T cells. These cells apparently bypassed the negative selection process, and some of them are potentially autoimmune. In infected animals, an atrophy of mesenteric lymph nodes is also observed, in contrast with the lymphocyte expansion in spleen and subcutaneous lymph nodes, illustrating a complex and organ specific dynamics of lymphocyte subpopulations. Accordingly, T- and B-cell activation is seen in subcutaneous lymph nodes and spleen, but not in mesenteric lymph nodes. Lastly, although the function of peripheral CD4+CD8+ T-cell population remains to be defined in vivo, their presence may contribute to the immunopathological events found in both murine and human Chagas disease.

  2. Diacylglycerol kinases in T cell tolerance and effector function

    Directory of Open Access Journals (Sweden)

    Shelley S Chen

    2016-11-01

    Full Text Available Diacylglycerol kinases (DGKs are a family of enzymes that regulate the relative levels of diacylglycerol (DAG and phosphatidic acid (PA in cells by phosphorylating DAG to produce PA. Both DAG and PA are important second messengers cascading T cell receptor (TCR signal by recruiting multiple effector molecules such as RasGRP1, PKC, and mTOR. Studies have revealed important physiological functions of DGKs in the regulation of receptor signaling and the development and activation of immune cells. In this review, we will focus on recent progresses in our understanding of two DGK isoforms,  and , in CD8 T effector and memory cell differentiation, regulatory T cell development and function, and invariant NKT cell development and effector lineage differentiation.

  3. Differential sensitivity of regulatory and effector T cells to cell death: a prerequisite for transplant tolerance

    Directory of Open Access Journals (Sweden)

    Sylvaine eYou

    2015-05-01

    Full Text Available Despite significant progress achieved in transplantation, immunosuppressive therapies currently used to prevent graft rejection are still endowed with severe side effects impairing their efficiency over the long term. Thus, the development of graft-specific, non toxic innovative therapeutic strategies has become a major challenge, the goal being to selectively target alloreactive effector T cells while sparing CD4+Foxp3+ regulatory T cells (Tregs to promote operational tolerance. Various approaches, notably the one based on monoclonal antibodies or fusion proteins directed against the TCR/CD3 complex, TCR coreceptors, or costimulatory molecules, have been proposed to reduce the alloreactive T cell pool which is an essential prerequisite to create a therapeutic window allowing Tregs to induce and maintain allograft tolerance. In this minireview, we focus on the differential sensitivity of Tregs and effector T cells to the depleting and inhibitory effect of these immunotherapies, with a particular emphasis on CD3-specific antibodies that beyond their immunosuppressive effect, also express potent tolerogenic capacities.

  4. Primary murine CD4+ T cells fail to acquire the ability to produce effector cytokines when active Ras is present during Th1/Th2 differentiation.

    Directory of Open Access Journals (Sweden)

    Sujit V Janardhan

    Full Text Available Constitutive Ras signaling has been shown to augment IL-2 production, reverse anergy, and functionally replace many aspects of CD28 co-stimulation in CD4+ T cells. These data raise the possibility that introduction of active Ras into primary T cells might result in improved functionality in pathologic situations of T cell dysfunction, such as cancer or chronic viral infection. To test the biologic effects of active Ras in primary T cells, CD4+ T cells from Coxsackie-Adenovirus Receptor Transgenic mice were transduced with an adenovirus encoding active Ras. As expected, active Ras augmented IL-2 production in naive CD4+ T cells. However, when cells were cultured for 4 days under conditions to promote effector cell differentiation, active Ras inhibited the ability of CD4+ T cells to acquire a Th1 or Th2 effector cytokine profile. This differentiation defect was not due to deficient STAT4 or STAT6 activation by IL-12 or IL-4, respectively, nor was it associated with deficient induction of T-bet and GATA-3 expression. Impaired effector cytokine production in active Ras-transduced cells was associated with deficient demethylation of the IL-4 gene locus. Our results indicate that, despite augmenting acute activation of naïve T cells, constitutive Ras signaling inhibits the ability of CD4+ T cells to properly differentiate into Th1/Th2 effector cytokine-producing cells, in part by interfering with epigenetic modification of effector gene loci. Alternative strategies to potentiate Ras pathway signaling in T cells in a more regulated fashion should be considered as a therapeutic approach to improve immune responses in vivo.

  5. Morphine Suppresses T helper Lymphocyte Differentiation to Th1 Type Through PI3K/AKT Pathway.

    Science.gov (United States)

    Mao, Mao; Qian, Yanning; Sun, Jie

    2016-04-01

    To investigate the effect of morphine on T helper lymphocyte differentiation and PI3K/AKT pathway mechanism, CD4+ lymphocytes were treated by phorbol-myristate-acetate (25 ng/ml) (PMA) plus ionomycin (1 μg/ml) in the presence of various concentrations of morphine (25, 50, 100, 200 ng/ml) for 4 h. Th1 and Th2 subsets, supernatant cytokines, and PI3K, AKT, and protein kinase C-theta (PKC-θ) levels were detected. The Th1 cell percentage, Th1-derived cytokines, and ratio of Th1/Th2 decreased in the presence of morphine in a concentration-dependent manner. However, Th2 cell percentage kept stable after morphine treatment. The phosphorylation of PI3K and AKT decreased, but the phosphorylation of PKC-θ did not change in the presence of morphine. The decreased percentage of Th1 cells and ratio of Th1/Th2 was recovered by naloxone concentration-dependently. Morphine can inhibit the differentiation of Th1 lymphocytes and decrease the ratio of Th1/Th2 via the pathway of PI3K/AKT. The effect can be inhibited by naloxone.

  6. Generation of specific antitumor cytotoxic T-lymphocytes in the monoculture

    International Nuclear Information System (INIS)

    Lupatov, A.Yu.; Brondz, B.D.

    1992-01-01

    A new model for the generation of specific antitumor cytotoxic T-lymphocytes (CTL) was proposed. In contrast to other models, it allows to generate effector CTL without immunization in vitro. For estimation of cytotoxic activity, chromium-51 release assay was used. It has been shown that effector CTL were absent in the lymph nodes in 1-fold as well as 2-fold immunization. Specific CTL were detected only after secondary immunization and subsequent cultivation in vitro. Effector cells had Thy1.2 + , Lyt2 + , L3T4 - phenotypes. Presence in vitro of exogenous IL-2 was needed for the generation of CTL against MX-11 sarcoma but not against EL4 lymphoma. The release of IL-2 from lymphomas cells could stimulate generation of the effector cells through activation of the endogenous production of IL-2, or due to some other factors

  7. Switch from perforin-expressing to perforin-deficient CD8(+) T cells accounts for two distinct types of effector cytotoxic T lymphocytes in vivo.

    Science.gov (United States)

    Meiraz, Avihai; Garber, Orit Gal; Harari, Shaul; Hassin, David; Berke, Gideon

    2009-09-01

    Although CD8(+) cytotoxic T lymphocytes (CTL) exhibit both Fas ligand (FasL) -based and perforin-based lytic activities, the accepted hallmark of a fully active CTL remains its perforin killing machinery. Yet the origin, rationale for possessing both a slow-acting (FasL) and a fast-acting (perforin) killing mechanism has remained enigmatic. Here we have investigated perforin expression in CTL directly involved in acute tumour (i.e. leukaemias EL4 and L1210) allograft rejection occurring within the peritoneal cavity. We show that at the height of the immune response, the majority of conjugate-forming CD8(+) CTL express high levels of perforin messenger RNA and protein, and kill essentially via perforin. Later however, coinciding with complete rejection, fully cytocidal CTL emerge which exhibit a stark decrease in perforin and now kill preferentially via constitutively expressed FasL. Although late in emergence, and persistent, these powerful CTL are neither effector-memory nor memory CTL. This finding has implications for the monitoring of anti-transplant responses in clinical settings, based on assessing perforin expression in graft infiltrating CD8(+) T cells. The results show that as the immune response progresses in vivo, targeted cellular suicide mainly prunes high perforin-expressing CD8(+) cells, resulting in the gradual switch in effector CTL, from mostly perforin-based to largely Fas/FasL-based killers. Hence, two kinds of CD8(+) CTL have two killing strategies.

  8. Switch from perforin-expressing to perforin-deficient CD8+ T cells accounts for two distinct types of effector cytotoxic T lymphocytes in vivo

    Science.gov (United States)

    Meiraz, Avihai; Garber, Orit Gal; Harari, Shaul; Hassin, David; Berke, Gideon

    2009-01-01

    Although CD8+ cytotoxic T lymphocytes (CTL) exhibit both Fas ligand (FasL) -based and perforin-based lytic activities, the accepted hallmark of a fully active CTL remains its perforin killing machinery. Yet the origin, rationale for possessing both a slow-acting (FasL) and a fast-acting (perforin) killing mechanism has remained enigmatic. Here we have investigated perforin expression in CTL directly involved in acute tumour (i.e. leukaemias EL4 and L1210) allograft rejection occurring within the peritoneal cavity. We show that at the height of the immune response, the majority of conjugate-forming CD8+ CTL express high levels of perforin messenger RNA and protein, and kill essentially via perforin. Later however, coinciding with complete rejection, fully cytocidal CTL emerge which exhibit a stark decrease in perforin and now kill preferentially via constitutively expressed FasL. Although late in emergence, and persistent, these powerful CTL are neither effector-memory nor memory CTL. This finding has implications for the monitoring of anti-transplant responses in clinical settings, based on assessing perforin expression in graft infiltrating CD8+ T cells. The results show that as the immune response progresses in vivo, targeted cellular suicide mainly prunes high perforin-expressing CD8+ cells, resulting in the gradual switch in effector CTL, from mostly perforin-based to largely Fas/FasL-based killers. Hence, two kinds of CD8+ CTL have two killing strategies. PMID:19689737

  9. Proliferation requirements of cytomegalovirus-specific, effector-type human CD8+ T cells

    NARCIS (Netherlands)

    van Leeuwen, Ester M.; Gamadia, Laila E.; Baars, Paul A.; Remmerswaal, Ester B.; ten Berge, Ineke J.; van Lier, René A.

    2002-01-01

    Two prototypic types of virus-specific CD8(+) T cells can be found in latently infected individuals: CD45R0(+)CD27(+)CCR7(-) effector-memory, and CD45RA(+)CD27(-)CCR7(-) effector-type cells. It has recently been implied that CD45RA(+)CD27(-)CCR7(-) T cells are terminally differentiated effector

  10. Bone Marrow Mesenchymal Stem Cells Enhance the Differentiation of Human Switched Memory B Lymphocytes into Plasma Cells in Serum-Free Medium

    Directory of Open Access Journals (Sweden)

    Guillaume Bonnaure

    2016-01-01

    Full Text Available The differentiation of human B lymphocytes into plasma cells is one of the most stirring questions with regard to adaptive immunity. However, the terminal differentiation and survival of plasma cells are still topics with much to be discovered, especially when targeting switched memory B lymphocytes. Plasma cells can migrate to the bone marrow in response to a CXCL12 gradient and survive for several years while secreting antibodies. In this study, we aimed to get closer to niches favoring plasma cell survival. We tested low oxygen concentrations and coculture with mesenchymal stem cells (MSC from human bone marrow. Besides, all cultures were performed using an animal protein-free medium. Overall, our model enables the generation of high proportions of CD38+CD138+CD31+ plasma cells (≥50% when CD40-activated switched memory B lymphocytes were cultured in direct contact with mesenchymal stem cells. In these cultures, the secretion of CXCL12 and TGF-β, usually found in the bone marrow, was linked to the presence of MSC. The level of oxygen appeared less impactful than the contact with MSC. This study shows for the first time that expanded switched memory B lymphocytes can be differentiated into plasma cells using exclusively a serum-free medium.

  11. Phenotypic complexity of T regulatory subsets in patients with B-chronic lymphocytic leukemia.

    Science.gov (United States)

    Biancotto, Angélique; Dagur, Pradeep K; Fuchs, John C; Wiestner, Adrian; Bagwell, C Bruce; McCoy, J Philip

    2012-02-01

    Increased numbers of T regulatory (T(reg)) cells are found in B-chronic lymphocytic leukemia, but the nature and function of these T(regs) remains unclear. Detailed characterization of the T(regs) in chronic lymphocytic leukemia has not been performed and the degree of heterogeneity of among these cells has not been studied to date. Using 15-color flow cytometry we show that T(reg) cells, defined using CD4, CD25, and forkhead box P3 (FOXP3), can be divided into multiple complex subsets based on markers used for naïve, memory, and effector delineation as well as markers of T(reg) activation. Furthermore FOXP3(+) cells can be identified among CD4(+)CD25(-) as well as CD8(+)CD4(-) populations in increased proportions in patients with chronic lymphocytic leukemia compared with healthy donors. Significantly different frequencies of naïve and effector T(regs) populations are found in healthy donor controls compared with donors with chronic lymphocytic leukemia. A population of CCR7(+)CD39(+) T(regs) was significantly associated with chronic lymphocytic leukemia. This population demonstrated slightly reduced suppressive activity compared with total T(regs) or T(regs) of healthy donors. These data suggest that FOXP3-expressing cells, particularly in patients with chronic lymphocytic leukemia are much more complex for T(reg) sub-populations and transitions than previously reported. These findings demonstrate the complexity of regulation of T-cell responses in chronic lymphocytic leukemia and illustrate the use of high-dimensional analysis of cellular phenotypes in facilitating understanding of the intricacies of cellular immune responses and their dysregulation in cancer.

  12. The essential role of chemokines in the selective regulation of lymphocyte homing.

    Science.gov (United States)

    Bono, María Rosa; Elgueta, Raúl; Sauma, Daniela; Pino, Karina; Osorio, Fabiola; Michea, Paula; Fierro, Alberto; Rosemblatt, Mario

    2007-01-01

    Knowledge of lymphocyte migration has become a major issue in our understanding of acquired immunity. The selective migration of naïve, effector, memory and regulatory T-cells is a multiple step process regulated by a specific arrangement of cytokines, chemokines and adhesion receptors that guide these cells to specific locations. Recent research has outlined two major pathways of lymphocyte trafficking under homeostatic and inflammatory conditions, one concerning tropism to cutaneous tissue and a second one related to mucosal-associated sites. In this article we will outline our present understanding of the role of cytokines and chemokines as regulators of lymphocyte migration through tissues.

  13. Timing of in utero malaria exposure influences fetal CD4 T cell regulatory versus effector differentiation

    Directory of Open Access Journals (Sweden)

    Mary Prahl

    2016-10-01

    Full Text Available Abstract Background In malaria-endemic areas, the first exposure to malaria antigens often occurs in utero when the fetal immune system is poised towards the development of tolerance. Children exposed to placental malaria have an increased risk of clinical malaria in the first few years of life compared to unexposed children. Recent work has suggested the potential of pregnancy-associated malaria to induce immune tolerance in children living in malaria-endemic areas. A study was completed to evaluate the effect of malaria exposure during pregnancy on fetal immune tolerance and effector responses. Methods Using cord blood samples from a cohort of mother-infant pairs followed from early in pregnancy until delivery, flow cytometry analysis was completed to assess the relationship between pregnancy-associated malaria and fetal cord blood CD4 and dendritic cell phenotypes. Results Cord blood FoxP3+ Treg counts were higher in infants born to mothers with Plasmodium parasitaemia early in pregnancy (12–20 weeks of gestation; p = 0.048, but there was no association between Treg counts and the presence of parasites in the placenta at the time of delivery (by loop-mediated isothermal amplification (LAMP; p = 0.810. In contrast, higher frequencies of activated CD4 T cells (CD25+FoxP3−CD127+ were observed in the cord blood of neonates with active placental Plasmodium infection at the time of delivery (p = 0.035. This population exhibited evidence of effector memory differentiation, suggesting priming of effector T cells in utero. Lastly, myeloid dendritic cells were higher in the cord blood of infants with histopathologic evidence of placental malaria (p < 0.0001. Conclusion Together, these data indicate that in utero exposure to malaria drives expansion of both regulatory and effector T cells in the fetus, and that the timing of this exposure has a pivotal role in determining the polarization of the fetal immune response.

  14. Curcumin serves as a human kv1.3 blocker to inhibit effector memory T lymphocyte activities.

    Science.gov (United States)

    Lian, Yi-Tian; Yang, Xiao-Fang; Wang, Zhao-Hui; Yang, Yong; Yang, Ying; Shu, Yan-Wen; Cheng, Long-Xian; Liu, Kun

    2013-09-01

    Curcumin, the principal active component of turmeric, has long been used to treat various diseases in India and China. Recent studies show that curcumin can serve as a therapeutic agent for autoimmune diseases via a variety of mechanisms. Effector memory T cells (T(EM), CCR7⁻ CD45RO⁺ T lymphocyte) have been demonstrated to play a crucial role in the pathogenesis of T cell-mediated autoimmune diseases, such as multiple sclerosis (MS) or rheumatoid arthritis (RA). Kv1.3 channels are predominantly expressed in T(EM) cells and control T(EM) activities. In the present study, we examined the effect of curcumin on human Kv1.3 (hKv1.3) channels stably expressed in HEK-293 cells and its ability to inhibit proliferation and cytokine secretion of T(EM) cells isolated from patients with MS or RA. Curcumin exhibited a direct blockage of hKv1.3 channels in a time-dependent and concentration-dependent manner. Moreover, the activation curve was shifted to a more positive potential, which was consistent with an open-channel blockade. Paralleling hKv1.3 inhibition, curcumin significantly inhibited proliferation and interferon-γ secretion of T(EM) cells. Our findings demonstrate that curcumin is able to inhibit proliferation and proinflammatory cytokine secretion of T(EM) cells probably through inhibition of hKv1.3 channels, which contributes to the potency of curcumin for the treatment of autoimmune diseases. This is probably one of pharmacological mechanisms of curcumin used to treat autoimmune diseases. Copyright © 2012 John Wiley & Sons, Ltd.

  15. Controlling transcription in human pluripotent stem cells using CRISPR-effectors.

    Science.gov (United States)

    Genga, Ryan M; Kearns, Nicola A; Maehr, René

    2016-05-15

    The ability to manipulate transcription in human pluripotent stem cells (hPSCs) is fundamental for the discovery of key genes and mechanisms governing cellular state and differentiation. Recently developed CRISPR-effector systems provide a systematic approach to rapidly test gene function in mammalian cells, including hPSCs. In this review, we discuss recent advances in CRISPR-effector technologies that have been employed to control transcription through gene activation, gene repression, and epigenome engineering. We describe an application of CRISPR-effector mediated transcriptional regulation in hPSCs by targeting a synthetic promoter driving a GFP transgene, demonstrating the ease and effectiveness of CRISPR-effector mediated transcriptional regulation in hPSCs. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. T-cell effector function and unresponsiveness in the murine lymphocytic choriomeningitis virus infection. II. Delayed-type hypersensitivity unresponsiveness reflects a defective differentiation from TD precursor to effector cell

    DEFF Research Database (Denmark)

    Thomsen, Allan Randrup; Marker, O

    1986-01-01

    is markedly depressed in high-dose mice, suggesting an association between DTH and virus clearance. When virus-primed memory cells are transferred, DTH reactivity as well as virus-clearing capacity is restored in high-dose mice, indicating that the virus is not present in a changed or concealed form. The role...... transfer a DTH response emerged, indicating that TD priming had taken place in high-dose animals. Pre-irradiation of high-dose primed cells markedly inhibited the antiviral activity as well as DTH, suggesting that upon transfer to naive recipients TD precursors from high-dose mice would proliferate...... precursor into effector cells which is reversible upon transfer to a less antigen loaded environment. Furthermore, it is suggested that TD function is crucial to the process of virus clearance....

  17. Autoreactive T effector memory differentiation mirrors β-cell function in type 1 diabetes.

    Science.gov (United States)

    Yeo, Lorraine; Woodwyk, Alyssa; Sood, Sanjana; Lorenc, Anna; Eichmann, Martin; Pujol-Autonell, Irma; Melchiotti, Rossella; Skowera, Ania; Fidanis, Efthymios; Dolton, Garry M; Tungatt, Katie; Sewell, Andrew K; Heck, Susanne; Saxena, Alka; Beam, Craig A; Peakman, Mark

    2018-05-31

    In type 1 diabetes, cytotoxic CD8 T cells with specificity for β-cell autoantigens are found in the pancreatic islets where they are implicated in the destruction of insulin-secreting β cells. In contrast, the disease relevance of β-cell-reactive CD8 T cells that are detectable in the circulation, and their relationship to β-cell function, are not known. Here, we tracked multiple, circulating β-cell-reactive CD8 T cell subsets and measured β-cell function longitudinally for two years, starting immediately after diagnosis of type 1 diabetes. We found that change in β-cell-specific effector memory CD8 T cells expressing CD57 was positively correlated with C-peptide change in subjects below 12 years of age. Autoreactive CD57+ effector memory CD8 T cells bore the signature of enhanced effector function (higher expression of granzyme B, killer specific protein 37 and CD16, and reduced expression of CD28) compared with their CD57-negative counterparts, and network association modelling indicated that the dynamics of β-cell-reactive CD57+ effector memory CD8 T cell subsets were strongly linked. Thus, coordinated changes in circulating β-cell-specific CD8 T cells within the CD57+ effector memory subset calibrate to functional insulin reserve in type 1 diabetes, providing a tool for immune monitoring and a mechanism-based target for immunotherapy.

  18. Life Stage-specific Proteomes of Legionella pneumophila Reveal a Highly Differential Abundance of Virulence-associated Dot/Icm effectors*

    Science.gov (United States)

    Aurass, Philipp; Gerlach, Thomas; Becher, Dörte; Voigt, Birgit; Karste, Susanne; Bernhardt, Jörg; Riedel, Katharina; Hecker, Michael; Flieger, Antje

    2016-01-01

    Major differences in the transcriptional program underlying the phenotypic switch between exponential and post-exponential growth of Legionella pneumophila were formerly described characterizing important alterations in infection capacity. Additionally, a third state is known where the bacteria transform in a viable but nonculturable state under stress, such as starvation. We here describe phase-related proteomic changes in exponential phase (E), postexponential phase (PE) bacteria, and unculturable microcosms (UNC) containing viable but nonculturable state cells, and identify phase-specific proteins. We present data on different bacterial subproteomes of E and PE, such as soluble whole cell proteins, outer membrane-associated proteins, and extracellular proteins. In total, 1368 different proteins were identified, 922 were quantified and 397 showed differential abundance in E/PE. The quantified subproteomes of soluble whole cell proteins, outer membrane-associated proteins, and extracellular proteins; 841, 55, and 77 proteins, respectively, were visualized in Voronoi treemaps. 95 proteins were quantified exclusively in E, such as cell division proteins MreC, FtsN, FtsA, and ZipA; 33 exclusively in PE, such as motility-related proteins of flagellum biogenesis FlgE, FlgK, and FliA; and 9 exclusively in unculturable microcosms soluble whole cell proteins, such as hypothetical, as well as transport/binding-, and metabolism-related proteins. A high frequency of differentially abundant or phase-exclusive proteins was observed among the 91 quantified effectors of the major virulence-associated protein secretion system Dot/Icm (> 60%). 24 were E-exclusive, such as LepA/B, YlfA, MavG, Lpg2271, and 13 were PE-exclusive, such as RalF, VipD, Lem10. The growth phase-related specific abundance of a subset of Dot/Icm virulence effectors was confirmed by means of Western blotting. We therefore conclude that many effectors are predominantly abundant at either E or PE which suggests

  19. Increased numbers of preexisting memory CD8 T cells and decreased T-bet expression can restrain terminal differentiation of secondary effector and memory CD8 T cells.

    Science.gov (United States)

    Joshi, Nikhil S; Cui, Weiguo; Dominguez, Claudia X; Chen, Jonathan H; Hand, Timothy W; Kaech, Susan M

    2011-10-15

    Memory CD8 T cells acquire effector memory cell properties after reinfection and may reach terminally differentiated, senescent states ("Hayflick limit") after multiple infections. The signals controlling this process are not well understood, but we found that the degree of secondary effector and memory CD8 T cell differentiation was intimately linked to the amount of T-bet expressed upon reactivation and preexisting memory CD8 T cell number (i.e., primary memory CD8 T cell precursor frequency) present during secondary infection. Compared with naive cells, memory CD8 T cells were predisposed toward terminal effector (TE) cell differentiation because they could immediately respond to IL-12 and induce T-bet, even in the absence of Ag. TE cell formation after secondary (2°) or tertiary infections was dependent on increased T-bet expression because T-bet(+/-) cells were resistant to these phenotypic changes. Larger numbers of preexisting memory CD8 T cells limited the duration of 2° infection and the amount of IL-12 produced, and consequently, this reduced T-bet expression and the proportion of 2° TE CD8 T cells that formed. Together, these data show that over repeated infections, memory CD8 T cell quality and proliferative fitness is not strictly determined by the number of serial encounters with Ag or cell divisions, but is a function of the CD8 T cell differentiation state, which is genetically controlled in a T-bet-dependent manner. This differentiation state can be modulated by preexisting memory CD8 T cell number and the intensity of inflammation during reinfection. These results have important implications for vaccinations involving prime-boost strategies.

  20. Lymphocytic Pleural Effusion in Acute Melioidosis

    Directory of Open Access Journals (Sweden)

    Kuo-Mou Chung

    2007-10-01

    Full Text Available An endemic outbreak of melioidosis developed in southern Taiwan following a flood caused by a typhoon in July 2005. A total of 27 patients were diagnosed with the acute and indigenous form of pulmonary melioidosis. Parapneumonic pleural effusions were noted on chest X-rays in six patients. Thoracentesis was done in three patients and all revealed lymphocyte predominance in differential cell count. Burkholderia pseudomallei was isolated in the pleural effusion in one of them. All three patients survived after antibiotic treatment. Lymphocytic pleural effusion is generally seen in tuberculosis or malignancy. However, our findings suggest that melioidosis should be considered in the differential diagnosis of lymphocytic pleural effusion.

  1. Obesity-Induced Metabolic Stress Leads to Biased Effector Memory CD4+ T Cell Differentiation via PI3K p110δ-Akt-Mediated Signals.

    Science.gov (United States)

    Mauro, Claudio; Smith, Joanne; Cucchi, Danilo; Coe, David; Fu, Hongmei; Bonacina, Fabrizia; Baragetti, Andrea; Cermenati, Gaia; Caruso, Donatella; Mitro, Nico; Catapano, Alberico L; Ammirati, Enrico; Longhi, Maria P; Okkenhaug, Klaus; Norata, Giuseppe D; Marelli-Berg, Federica M

    2017-03-07

    Low-grade systemic inflammation associated to obesity leads to cardiovascular complications, caused partly by infiltration of adipose and vascular tissue by effector T cells. The signals leading to T cell differentiation and tissue infiltration during obesity are poorly understood. We tested whether saturated fatty acid-induced metabolic stress affects differentiation and trafficking patterns of CD4 + T cells. Memory CD4 + T cells primed in high-fat diet-fed donors preferentially migrated to non-lymphoid, inflammatory sites, independent of the metabolic status of the hosts. This was due to biased CD4 + T cell differentiation into CD44 hi -CCR7 lo -CD62L lo -CXCR3 + -LFA1 + effector memory-like T cells upon priming in high-fat diet-fed animals. Similar phenotype was observed in obese subjects in a cohort of free-living people. This developmental bias was independent of any crosstalk between CD4 + T cells and dendritic cells and was mediated via direct exposure of CD4 + T cells to palmitate, leading to increased activation of a PI3K p110δ-Akt-dependent pathway upon priming. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  2. Primary and Chronic HIV Infection Differently Modulates Mucosal Vδ1 and Vδ2 T-Cells Differentiation Profile and Effector Functions.

    Directory of Open Access Journals (Sweden)

    Eleonora Cimini

    Full Text Available Gut-associated immune system has been identified as a major battlefield during the early phases of HIV infection. γδ T-cells, deeply affected in number and function after HIV infection, are able to act as a first line of defence against invading pathogens by producing antiviral soluble factors and by killing infected cells. Despite the relevant role in mucosal immunity, few data are available on gut-associated γδ T-cells during HIV infection. Aim of this work was to evaluate how primary (P-HIV and chronic (C-HIV HIV infection affects differentiation profile and functionality of circulating and gut-associated Vδ1 and Vδ2 T-cells. In particular, circulating and mucosal cells were isolated from respectively whole blood and residual gut samples from HIV-infected subjects with primary and chronic infection and from healthy donors (HD. Differentiation profile and functionality were analyzed by multiparametric flow cytometry. P-HIV and C-HIV were characterized by an increase in the frequency of effector Vδ1-T cells both in circulating and mucosal compartments. Moreover, during P-HIV mucosal Vδ1 T-cells expressed high levels of CD107a, suggesting a good effector cytotoxic capability of these cells in the early phase of infection that was lost in C-HIV. P-HIV induced an increase in circulating effector Vδ2 T-cells in comparison to C-HIV and HD. Notably, P-HIV as well as HD were characterized by the ability of mucosal Vδ2 T-cells to spontaneously produce IFN-γ that was lost in C-HIV. Altogether, our data showed for the first time a functional capability of mucosal Vδ1 and Vδ2 T-cells during P-HIV that was lost in C-HIV, suggesting exhaustion mechanisms induced by persistent stimulation.

  3. Novel Strategy for Phenotypic Characterization of Human B Lymphocytes from Precursors to Effector Cells by Flow Cytometry.

    Directory of Open Access Journals (Sweden)

    Giovanna Clavarino

    Full Text Available A precise identification and phenotypic characterization of human B-cell subsets is of crucial importance in both basic research and medicine. In the literature, flow cytometry studies for the phenotypic characterization of B-lymphocytes are mainly focused on the description of a particular cell stage, or of specific cell stages observed in a single type of sample. In the present work, we propose a backbone of 6 antibodies (CD38, CD27, CD10, CD19, CD5 and CD45 and an efficient gating strategy to identify, in a single analysis tube, a large number of B-cell subsets covering the whole B-cell differentiation from precursors to memory and plasma cells. Furthermore, by adding two antibodies in an 8-color combination, our approach allows the analysis of the modulation of any cell surface marker of interest along B-cell differentiation. We thus developed a panel of seven 8-colour antibody combinations to phenotypically characterize B-cell subpopulations in bone marrow, peripheral blood, lymph node and cord blood samples. Beyond qualitative information provided by biparametric representations, we also quantified antigen expression on each of the identified B-cell subsets and we proposed a series of informative curves showing the modulation of seventeen cell surface markers along B-cell differentiation. Our approach by flow cytometry provides an efficient tool to obtain quantitative data on B-cell surface markers expression with a relative easy-to-handle technique that can be applied in routine explorations.

  4. Death Receptor 3 Signaling Controls the Balance between Regulatory and Effector Lymphocytes in SAMP1/YitFc Mice with Crohn’s Disease-Like Ileitis

    Directory of Open Access Journals (Sweden)

    Zhaodong Li

    2018-03-01

    Full Text Available Death receptor 3 (DR3, a member of the tumor necrosis factor receptor (TNFR superfamily, has been implicated in regulating T-helper type-1 (TH1, type-2 (TH2, and type-17 (TH17 responses as well as regulatory T cell (Treg and innate lymphoid cell (ILC functions during immune-mediated diseases. However, the role of DR3 in controlling lymphocyte functions in inflammatory bowel disease (IBD is not fully understood. Recent studies have shown that activation of DR3 signaling modulates Treg expansion suggesting that stimulation of DR3 represents a potential therapeutic target in human inflammatory diseases, including Crohn’s disease (CD. In this study, we tested a specific DR3 agonistic antibody (4C12 in SAMP1/YitFc (SAMP mice with CD-like ileitis. Interestingly, treatment with 4C12 prior to disease manifestation markedly worsened the severity of ileitis in SAMP mice despite an increase in FoxP3+ lymphocytes in mesenteric lymph node (MLN and small-intestinal lamina propria (LP cells. Disease exacerbation was dominated by overproduction of both TH1 and TH2 cytokines and associated with expansion of dysfunctional CD25−FoxP3+ and ILC group 1 (ILC1 cells. These effects were accompanied by a reduction in CD25+FoxP3+ and ILC group 3 (ILC3 cells. By comparison, genetic deletion of DR3 effectively reversed the inflammatory phenotype in SAMP mice by promoting the expansion of CD25+FoxP3+ over CD25−FoxP3+ cells and the production of IL-10 protein. Collectively, our data demonstrate that DR3 signaling modulates a multicellular network, encompassing Tregs, T effectors, and ILCs, governing disease development and progression in SAMP mice with CD-like ileitis. Manipulating DR3 signaling toward the restoration of the balance between protective and inflammatory lymphocytes may represent a novel and targeted therapeutic modality for patients with CD.

  5. Effect of IL-4 and IL-6 on the proliferation and differentiation of B-chronic lymphocytic leukemia cells

    NARCIS (Netherlands)

    van Kooten, C.; Rensink, I.; Aarden, L.; van Oers, R.

    1993-01-01

    The proliferation and differentiation of purified malignant B cells from nine patients with chronic lymphocytic leukemia (B-CLL) were studied in vitro. We have demonstrated before that tumour necrosis factor alpha (TNF-alpha), in combination with low dose phorbol myristic acid (PMA) (0.1 ng/ml), can

  6. Functional heterogeneity of human effector CD8+ T cells.

    Science.gov (United States)

    Takata, Hiroshi; Naruto, Takuya; Takiguchi, Masafumi

    2012-02-09

    Effector CD8(+) T cells are believed to be terminally differentiated cells having cytotoxic activity and the ability to produce effector cytokines such as INF-γ and TNF-α. We investigated the difference between CXCR1(+) and CXCR1(-) subsets of human effector CD27(-)CD28(-)CD8(+) T cells. The subsets expressed cytolytic molecules similarly and exerted substantial cytolytic activity, whereas only the CXCR1(-) subset had IL-2 productivity and self-proliferative activity and was more resistant to cell death than the CXCR1(+) subset. These differences were explained by the specific up-regulation of CAMK4, SPRY2, and IL-7R in the CXCR1(-) subset and that of pro-apoptotic death-associated protein kinase 1 (DAPK1) in the CXCR1(+) subset. The IL-2 producers were more frequently found in the IL-7R(+) subset of the CXCR1(-) effector CD8(+) T cells than in the IL-7R(-) subset. IL-7/IL-7R signaling promoted cell survival only in the CXCR1(-) subset. The present study has highlighted a novel subset of effector CD8(+) T cells producing IL-2 and suggests the importance of this subset in the homeostasis of effector CD8(+) T cells.

  7. Wnt-10b secreted from lymphocytes promotes differentiation of skin epithelial cells

    International Nuclear Information System (INIS)

    Ouji, Yukiteru; Yoshikawa, Masahide; Shiroi, Akira; Ishizaka, Shigeaki

    2006-01-01

    Wnt-10b was originally isolated from lymphoid tissue and is known to be involved in a wide range of biological actions, while recently it was found to be expressed early in the development of hair follicles. However, few studies have been conducted concerning the role of Wnt-10b with the differentiation of skin epithelial cells. To evaluate its role in epithelial differentiation, we purified Wnt-10b from the supernatant of a concanavalin A-stimulated lymphocyte culture using an affinity column and investigated its effects on the differentiation of adult mouse-derived primary skin epithelial cells (MPSEC). MPSEC cultured with Wnt-10b showed morphological changes from cuboidal to spindle-shaped with inhibited proliferation, and also obtained characteristics of the hair shaft and inner root sheath of the hair follicle, represented by red-colored Ayoub Shklar staining, and reactions to AE-13 and AE-15 as seen with immunocytology. Further, RT-PCR analysis demonstrated the expression of mRNA for keratin 1, keratin 2, loricrin, mHa5, and mHb5, in association with a decreased expression of the basal cell marker keratin 5, in Wnt-10b-treated MPSEC. In addition, involvement of the canonical Wnt signal pathway was demonstrated by a TCF reporter (pTOPFLASH) assay. These results suggest that Wnt-10b promotes the differentiation of MPSEC and may play an important role in hair follicle development by promoting differentiation of epithelial cells

  8. The barley powdery mildew effector candidates CSEP0081 and CSEP0254 promote fungal infection success

    DEFF Research Database (Denmark)

    Ahmed, Ali Abdurehim; Pedersen, Carsten; Thordal-Christensen, Hans

    2016-01-01

    Effectors play significant roles in the success of pathogens. Recent advances in genome sequencing have revealed arrays of effectors and effector candidates from a wide range of plant pathogens. Yet, the vast majority of them remain uncharacterized. Among the ~500 Candidate Secreted Effector...... independent silencing of the transcripts for these CSEPs significantly reduced the fungal penetration and haustoria formation rate. Both CSEPs are likely required during and after the formation of haustoria, in which their transcripts were found to be differentially expressed, rather than in epiphytic tissue...

  9. A novel differentiation pathway from CD4⁺ T cells to CD4⁻ T cells for maintaining immune system homeostasis.

    Science.gov (United States)

    Zhao, X; Sun, G; Sun, X; Tian, D; Liu, K; Liu, T; Cong, M; Xu, H; Li, X; Shi, W; Tian, Y; Yao, J; Guo, H; Zhang, D

    2016-04-14

    CD4(+) T lymphocytes are key players in the adaptive immune system and can differentiate into a variety of effector and regulatory T cells. Here, we provide evidence that a novel differentiation pathway of CD4(+) T cells shifts the balance from a destructive T-cell response to one that favors regulation in an immune-mediated liver injury model. Peripheral CD4(-)CD8(-)NK1.1(-) double-negative T cells (DNT) was increased following Concanavalin A administration in mice. Adoptive transfer of DNT led to significant protection from hepatocyte necrosis by direct inhibition on the activation of lymphocytes, a process that occurred primarily through the perforin-granzyme B route. These DNT converted from CD4(+) rather than CD8(+) T cells, a process primarily regulated by OX40. DNT migrated to the liver through the CXCR3-CXCL9/CXCL10 interaction. In conclusion, we elucidated a novel differentiation pathway from activated CD4(+) T cells to regulatory DNT cells for maintaining homeostasis of the immune system in vivo, and provided key evidence that utilizing this novel differentiation pathway has potential application in the prevention and treatment of autoimmune diseases.

  10. Imaging Polarized Secretory Traffic at the Immune Synapse in Living T Lymphocytes.

    Science.gov (United States)

    Calvo, Víctor; Izquierdo, Manuel

    2018-01-01

    Immune synapse (IS) formation by T lymphocytes constitutes a crucial event involved in antigen-specific, cellular and humoral immune responses. After IS formation by T lymphocytes and antigen-presenting cells, the convergence of secretory vesicles toward the microtubule-organizing center (MTOC) and MTOC polarization to the IS are involved in polarized secretion at the synaptic cleft. This specialized mechanism appears to specifically provide the immune system with a fine strategy to increase the efficiency of crucial secretory effector functions of T lymphocytes, while minimizing non-specific, cytokine-mediated stimulation of bystander cells, target cell killing and activation-induced cell death. The molecular bases involved in the polarized secretory traffic toward the IS in T lymphocytes have been the focus of interest, thus different models and several imaging strategies have been developed to gain insights into the mechanisms governing directional secretory traffic. In this review, we deal with the most widely used, state-of-the-art approaches to address the molecular mechanisms underlying this crucial, immune secretory response.

  11. Growing B Lymphocytes in a Three-Dimensional Culture System

    Science.gov (United States)

    Wu, J. H. David; Bottaro, Andrea

    2010-01-01

    A three-dimensional (3D) culture system for growing long-lived B lymphocytes has been invented. The capabilities afforded by the system can be expected to expand the range of options for immunological research and related activities, including testing of immunogenicity of vaccine candidates in vitro, generation of human monoclonal antibodies, and immunotherapy. Mature lymphocytes, which are the effectors of adaptive immune responses in vertebrates, are extremely susceptible to apoptotic death, and depend on continuous reception of survival-inducing stimulation (in the forms of cytokines, cell-to-cell contacts, and antigen receptor signaling) from the microenvironment. For this reason, efforts to develop systems for long-term culture of functional, non-transformed and non-activated mature lymphocytes have been unsuccessful until now. The bone-marrow microenvironment supports the growth and differentiation of many hematopoietic lineages, in addition to B-lymphocytes. Primary bone-marrow cell cultures designed to promote the development of specific cell types in vitro are highly desirable experimental systems, amenable to manipulation under controlled conditions. However, the dynamic and complex network of stromal cells and insoluble matrix proteins is disrupted in prior plate- and flask-based culture systems, wherein the microenvironments have a predominantly two-dimensional (2D) character. In 2D bone-marrow cultures, normal B-lymphoid cells become progressively skewed toward precursor B-cell populations that do not retain a normal immunophenotype, and such mature B-lymphocytes as those harvested from the spleen or lymph nodes do not survive beyond several days ex vivo in the absence of mitogenic stimulation. The present 3D culture system is a bioreactor that contains highly porous artificial scaffolding that supports the long-term culture of bone marrow, spleen, and lymph-node samples. In this system, unlike in 2D culture systems, B-cell subpopulations developing

  12. CD8+ T lymphocyte expansion, proliferation and activation in dengue fever.

    Directory of Open Access Journals (Sweden)

    Andréia Manso de Matos

    2015-02-01

    Full Text Available Dengue fever induces a robust immune response, including massive T cell activation. The level of T cell activation may, however, be associated with more severe disease. In this study, we explored the level of CD8+ T lymphocyte activation in the first six days after onset of symptoms during a DENV2 outbreak in early 2010 on the coast of São Paulo State, Brazil. Using flow cytometry we detected a progressive increase in the percentage of CD8+ T cells in 74 dengue fever cases. Peripheral blood mononuclear cells from 30 cases were thawed and evaluated using expanded phenotyping. The expansion of the CD8+ T cells was coupled with increased Ki67 expression. Cell activation was observed later in the course of disease, as determined by the expression of the activation markers CD38 and HLA-DR. This increased CD8+ T lymphocyte activation was observed in all memory subsets, but was more pronounced in the effector memory subset, as defined by higher CD38 expression. Our results show that most CD8+ T cell subsets are expanded during DENV2 infection and that the effector memory subset is the predominantly affected sub population.

  13. Role of Circulating Lymphocytes in Patients with Sepsis

    Directory of Open Access Journals (Sweden)

    Raul de Pablo

    2014-01-01

    Full Text Available Sepsis is a systemic inflammatory response syndrome due to infection. The incidence rate is estimated to be up to 19 million cases worldwide per year and the number of cases is rising. Infection triggers a complex and prolonged host response, in which both the innate and adaptive immune response are involved. The disturbance of immune system cells plays a key role in the induction of abnormal levels of immunoregulatory molecules. Furthermore, the involvement of effector immune system cells also impairs the host response to the infective agents and tissue damage. Recently, postmortem studies of patients who died of sepsis have provided important insights into why septic patients die and showed an extensive depletion of CD4 and CD8 lymphocytes and they found that circulating blood cells showed similar findings. Thus, the knowledge of the characterization of circulating lymphocyte abnormalities is relevant for the understanding of the sepsis pathophysiology. In addition, monitoring the immune response in sepsis, including circulating lymphocyte subsets count, appears to be potential biomarker for predicting the clinical outcome of the patient. This paper analyzes the lymphocyte involvement and dysfunction found in patients with sepsis and new opportunities to prevent sepsis and guide therapeutic intervention have been revealed.

  14. Immunophenotypic lymphocyte profiles in human african trypanosomiasis.

    Directory of Open Access Journals (Sweden)

    Caroline Boda

    Full Text Available Human African trypanosomiasis (HAT is a deadly vector-born disease caused by an extracellular parasite, the trypanosome. Little is known about the cellular immune responses elicited by this parasite in humans. We used multiparameter flow cytometry to characterize leukocyte immunophenotypes in the blood and cerebrospinal fluid (CSF of 33 HAT patients and 27 healthy controls identified during a screening campaign in Angola and Gabon. We evaluated the subsets and activation markers of B and T lymphocytes. Patients had a higher percentage of CD19+ B lymphocytes and activated B lymphocytes in the blood than did controls, but lacked activated CD4+ T lymphocytes (CD25+. Patients displayed no increase in the percentage of activated CD8+ T cells (HLA-DR+, CD69+ or CD25+, but memory CD8 T-cell levels (CD8+CD45RA2 were significantly lower in patients than in controls, as were effector CD8 T-cell levels (CD8+CD45RA+CD62L2. No relationship was found between these blood immunophenotypes and disease severity (stage 1 vs 2. However, CD19+ B-cell levels in the CSF increased with disease severity. The patterns of T and B cell activation in HAT patients suggest that immunomodulatory mechanisms may operate during infection. Determinations of CD19+ B-cell levels in the CSF could improve disease staging.

  15. Differentiation of peripheral lymphocyte population in Pu-exposed beagle dogs

    International Nuclear Information System (INIS)

    Morris, J.E.

    1977-01-01

    The percentage of peripheral lymphocytes binding fluorescent-labeled anticanine antibodies was measured in plutonium-oxide-exposed and unexposed beagle dogs. With this assay system, there was a significant decrease in the percentage of lymphocytes binding the labeled antibody in exposed animals compared to control animals

  16. Laboratorial diagnosis of lymphocytic meningitis

    Directory of Open Access Journals (Sweden)

    Sérgio Monteiro de Almeida

    Full Text Available Meningitis is the main infectious central nervous system (CNS syndrome. Viruses or bacteria can cause acute meningitis of infectious etiology. The term "Aseptic Meningitis" denotes a clinical syndrome with a predominance of lymphocytes in the cerebrospinal fluid (CSF, with no common bacterial agents identified in the CSF. Viral meningitis is considered the main cause of lymphocyte meningitis. There are other etiologies of an infectious nature. CSF examination is essential to establish the diagnosis and to identify the etiological agent of lymphocytic meningitis. We examined CSF characteristics and the differential diagnosis of the main types of meningitis.

  17. The Influence of Macronutrients on Splanchnic and Hepatic Lymphocytes in Aging Mice.

    Science.gov (United States)

    Le Couteur, David G; Tay, Szun S; Solon-Biet, Samantha; Bertolino, Patrick; McMahon, Aisling C; Cogger, Victoria C; Colakoglu, Feyza; Warren, Alessandra; Holmes, Andrew J; Pichaud, Nicolas; Horan, Martin; Correa, Carolina; Melvin, Richard G; Turner, Nigel; Ballard, J William O; Ruohonen, Kari; Raubenheimer, David; Simpson, Stephen J

    2015-12-01

    There is a strong association between aging, diet, and immunity. The effects of macronutrients and energy intake on splanchnic and hepatic lymphocytes were studied in 15 month old mice. The mice were ad-libitum fed 1 of 25 diets varying in the ratios and amounts of protein, carbohydrate, and fat over their lifetime. Lymphocytes in liver, spleen, Peyers patches, mesenteric lymph nodes, and inguinal lymph nodes were evaluated using flow cytometry. Low protein intake reversed aging changes in splenic CD4 and CD8 T cells, CD4:CD8 T cell ratio, memory/effector CD4 T cells and naïve CD4 T cells. A similar influence of total caloric intake in these ad-libitum fed mice was not apparent. Protein intake also influenced hepatic NK cells and B cells, while protein to carbohydrate ratio influenced hepatic NKT cells. Hepatosteatosis was associated with increased energy and fat intake and changes in hepatic Tregs, effector/memory T, and NK cells. Hepatic NK cells were also associated with body fat, glucose tolerance, and leptin levels while hepatic Tregs were associated with hydrogen peroxide production by hepatic mitochondria. Dietary macronutrients, particularly protein, influence splanchnic lymphocytes in old age, with downstream associations with mitochondrial function, liver pathology, and obesity-related phenotype. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. Varied sensitivity to therapy of HIV-1 strains in CD4+ lymphocyte subpopulations upon ART initiation

    NARCIS (Netherlands)

    Heeregrave, Edwin J.; Geels, Mark J.; Baan, Elly; van der Sluis, Renee M.; Paxton, William A.; Pollakis, Georgios

    2010-01-01

    ABSTRACT: BACKGROUND: Although antiretroviral therapy (ART) has proven its success against HIV-1, the long lifespan of infected cells and viral latency prevent eradication. In this study we analyzed the sensitivity to ART of HIV-1 strains in naive, central memory and effector memory CD4+ lymphocyte

  19. STAT3 induces transcription of the DNA methyltransferase 1 gene (DNMT1) in malignant T lymphocytes

    DEFF Research Database (Denmark)

    Zhang, Qian; Wang, Hong Y; Woetmann, Anders

    2006-01-01

    In this study, we demonstrated that STAT3, a well-characterized transcription factor expressed in continuously activated oncogenic form in the large spectrum of cancer types, induces in malignant T lymphocytes the expression of DNMT1, the key effector of epigenetic gene silencing. STAT3 binds in ...

  20. Alloreactive cytotoxic T lymphocytes from aged mice express increased lysis of autologous and third-party target cells

    NARCIS (Netherlands)

    Kruisbeek, A.M.; Steinmeier, F.A.

    1980-01-01

    Much data support the notion that with increasing age a decline in T cell effector function occurs. In the present study, qualitative rather than quantitative age-related changes in vitro alloreactive cytotoxic T lymphocyte (CTL) responses were observed. The level of specific alloreactive CTL

  1. Compromised virus control and augmented perforin-mediated immunopathology in IFN-gamma-deficient mice infected with lymphocytic choriomeningitis virus

    DEFF Research Database (Denmark)

    Nansen, A; Jensen, Teis; Christensen, Jan Pravsgaard

    1999-01-01

    To define the role of IFN-gamma in the control of acute infection with a noncytopathogenic virus, mice with targeted defects of the genes encoding IFN-gamma, perforin, or both were infected i.v. with two strains of lymphocytic choriomeningitis virus differing markedly in their capacity to spread...... in wild-type mice. Our results reveal that IFN-gamma is pivotal to T cell-mediated control of a rapidly invasive stain, whereas it is less important in the acute elimination of a slowly invasive strain. Moreover, the majority of mice infected with the rapidly invasive strain succumb to a wasting syndrome...... mediated by CD8+ effector cells. The primary effector mechanism underlying this disease is perforin-dependent lysis, but other mechanisms are also involved. Wasting disease can be prevented if naive CD8+ cells from mice transgenic for an MHC class I-restricted lymphocytic choriomeningitis virus...

  2. Mechanisms involved in the differential recovery of CD4 and CD8 T-lymphocytes after local irradiation in mice

    International Nuclear Information System (INIS)

    De Ruysscher, D; Waer, M.; Vandeputte, M.; Van der Schueren, E.

    1990-01-01

    The mechanisms involved in the differential recovery of CD4 (helper/inducer phenotype) and CD8 (Cytotoxic/suppressor phenotype) T-lymphocytes after fractionated local irradiation were investigated. In mice, a better recovery of CD4 cells than of CD8 cells was found, while the reverse has been described in humans. Differences in radiosensivitity between CD4 and CD8 mouse splenocytes could not be found. No sequestration of CD8 cells in irradiated tissues could be demonstrated. Irradiation of the thymus did not influence the observed immune changes. Altered thymic production of CD4 and CD8 cells could be excluded by intrathymic injection of FITC (fluorescein isothiocyanate). Hindlimb and tail irradiation did suggest that the differential recovery of CD4 and CD8 T-lymphocytes after local irradiation is determined by extrathymic factors in man and mice, and that the observed differences in immune recovery between man and mice are due to defective thymic function in the former and normal function in the latter. (author). 12 refs.; 5 figs.; 2 tabs

  3. B Lymphocytes: Development, Tolerance, and Their Role in Autoimmunity—Focus on Systemic Lupus Erythematosus

    Directory of Open Access Journals (Sweden)

    Gabriel J. Tobón

    2013-01-01

    Full Text Available B lymphocytes are the effectors of humoral immunity, providing defense against pathogens through different functions including antibody production. B cells constitute approximately 15% of peripheral blood leukocytes and arise from hemopoietic stem cells in the bone marrow. It is here that their antigen receptors (surface immunoglobulin are assembled. In the context of autoimmune diseases defined by B and/or T cell autoreactive that upon activation lead to chronic tissue inflammation and often irreversible structural and functional damage, B lymphocytes play an essential role by not only producing autoantibodies but also functioning as antigen-presenting cells (APC and as a source of cytokines. In this paper, we describe B lymphocyte functions in autoimmunity and autoimmune diseases with a special focus on their abnormalities in systemic lupus erythematosus.

  4. Profiling calcium signals of in vitro polarized human effector CD4+ T cells.

    Science.gov (United States)

    Kircher, Sarah; Merino-Wong, Maylin; Niemeyer, Barbara A; Alansary, Dalia

    2018-06-01

    Differentiation of naïve CD4 + T cells into effector subtypes with distinct cytokine profiles and physiological roles is a tightly regulated process, the imbalance of which can lead to an inadequate immune response or autoimmune disease. The crucial role of Ca 2+ signals, mainly mediated by the store operated Ca 2+ entry (SOCE) in shaping the immune response is well described. However, it is unclear if human effector CD4 + T cell subsets show differential Ca 2+ signatures in response to different stimulation methods. Herein, we provide optimized in vitro culture conditions for polarization of human CD4 + effector T cells and characterize their SOCE following both pharmacological store depletion and direct T-cell receptor (TCR) activation. Moreover, we measured whole cell Ca 2+ release activated Ca 2+ currents (I CRAC ) and investigated whether the observed differences correlate to the expression of CRAC genes. Our results show that Ca 2+ profiles of helper CD4 + Th1, Th2 and Th17 are distinct and in part shaped by the intensity of stimulation. Regulatory T cells (Treg) are unique being the subtype with the most prominent SOCE response. Analysis of in vivo differentiated Treg unraveled the role of differential expression of ORAI2 in fine-tuning signals in Treg vs. conventional CD4 + T cells. Copyright © 2018 The Author(s). Published by Elsevier B.V. All rights reserved.

  5. Immune Response Induction and New Effector Mechanisms Possibly Involved in Protection Conferred by the Cuban Anti-Meningococcal BC Vaccine

    Science.gov (United States)

    Pérez, Oliver; Lastre, Miriam; Lapinet, José; Bracho, Gustavo; Díaz, Miriam; Zayas, Caridad; Taboada, Carlos; Sierra, Gustavo

    2001-01-01

    This report explores the participation of some afferent mechanisms in the immune response induced by the Cuban anti-meningococcal vaccine VA-MENGOC-BC. The induction of delayed-type hypersensitivity in nursing babies and lymphocyte proliferation after immunization is demonstrated. The presence of gamma interferon IFN-γ and interleukin-2 (IL-2) mRNAs but absence of IL-4, IL-5, and IL-10 mRNAs were observed in peripheral blood mononuclear cells from immunized subjects after in vitro challenge with outer membrane vesicles. In addition, some effector functions were also explored. The presence of opsonic activity was demonstrated in sera from vaccinees. The role of neutrophils as essential effector cells was shown. In conclusion, we have shown that, at least in the Cuban adult population, VA-MENGOC-BC induces mechanisms with a T-helper 1 pattern in the afferent and effector branches of the immune response. PMID:11401992

  6. Diagnostic utility of CD4%:CD8 low% T-lymphocyte ratio to differentiate feline immunodeficiency virus (FIV)-infected from FIV-vaccinated cats.

    Science.gov (United States)

    Litster, Annette; Lin, Jui-Ming; Nichols, Jamieson; Weng, Hsin-Yi

    2014-06-04

    Antibody testing based on individual risk assessments is recommended to determine feline immunodeficiency virus (FIV) status, but ELISA and Western blot tests cannot distinguish between anti-FIV antibodies produced in response to natural infection and those produced in response to FIV vaccination. The aim of this cross-sectional study was to test the hypothesis that FIV-infected cats could be differentiated from FIV-vaccinated uninfected cats using lymphocyte subset results, specifically the CD4%:CD8(low)% T-lymphocyte ratio. Comparisons of the CD4%:CD8(low)% T-lymphocyte ratio were made among the following four groups: Group 1 - FIV-infected cats (n=61; FIV-antibody positive by ELISA and FIV PCR positive); Group 2 - FIV-uninfected cats (n=96; FIV-antibody negative by ELISA); Group 3 - FIV-vaccinated uninfected cats (n=31; FIV-antibody negative by ELISA before being vaccinated against FIV, after which they tested FIV ELISA positive); and Group 4 - FIV-uninfected but under chronic/active antigenic stimulation (n=16; FIV-antibody negative by ELISA; all had active clinical signs of either upper respiratory tract disease or gingival disease for ≥ 21 days). The median CD4%:CD8(low)% T-lymphocyte ratio was lower in Group 1 (1.39) than in each of the other three groups (Group 2 - 9.77, Group 3 - 9.72, Group 4 - 5.64; P<0.05). The CD4%:CD8(low)% T-lymphocyte ratio was also the most effective discriminator between FIV-infected cats and the other three groups, and areas under ROC curves ranged from 0.91 (compared with Group 4) to 0.96 (compared with Group 3). CD4%:CD8(low)% shows promise as an effective test to differentiate between FIV-infected cats and FIV-vaccinated uninfected cats. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Mesenchymal stromal cells derived from cervical cancer produce high amounts of adenosine to suppress cytotoxic T lymphocyte functions

    Directory of Open Access Journals (Sweden)

    María de Lourdes Mora-García

    2016-10-01

    Full Text Available Abstract Background In recent years, immunomodulatory mechanisms of mesenchymal stem/stromal cells (MSCs from bone marrow and other “classic” sources have been described. However, the phenotypic and functional properties of tumor MSCs are poorly understood. The aim of this study was to analyze the immunosuppressive capacity of cervical cancer-derived MSCs (CeCa-MSCs on effector T lymphocytes through the purinergic pathway. Methods We determined the expression and functional activity of the membrane-associated ectonucleotidases CD39 and CD73 on CeCa-MSCs and normal cervical tissue-derived MSCs (NCx-MSCs. We also analyzed their immunosuppressive capacity to decrease proliferation, activation and effector cytotoxic T (CD8+ lymphocyte function through the generation of adenosine (Ado. Results We detected that CeCa-MSCs express higher levels of CD39 and CD73 ectonucleotidases in cell membranes compared to NCx-MSCs, and that this feature was associated with the ability to strongly suppress the proliferation, activation and effector functions of cytotoxic T-cells through the generation of large amounts of Ado from the hydrolysis of ATP, ADP and AMP nucleotides. Conclusions This study suggests that CeCa-MSCs play an important role in the suppression of the anti-tumor immune response in CeCa through the purinergic pathway.

  8. Mesenchymal stromal cells derived from cervical cancer produce high amounts of adenosine to suppress cytotoxic T lymphocyte functions.

    Science.gov (United States)

    de Lourdes Mora-García, María; García-Rocha, Rosario; Morales-Ramírez, Omar; Montesinos, Juan José; Weiss-Steider, Benny; Hernández-Montes, Jorge; Ávila-Ibarra, Luis Roberto; Don-López, Christian Azucena; Velasco-Velázquez, Marco Antonio; Gutiérrez-Serrano, Vianey; Monroy-García, Alberto

    2016-10-26

    In recent years, immunomodulatory mechanisms of mesenchymal stem/stromal cells (MSCs) from bone marrow and other "classic" sources have been described. However, the phenotypic and functional properties of tumor MSCs are poorly understood. The aim of this study was to analyze the immunosuppressive capacity of cervical cancer-derived MSCs (CeCa-MSCs) on effector T lymphocytes through the purinergic pathway. We determined the expression and functional activity of the membrane-associated ectonucleotidases CD39 and CD73 on CeCa-MSCs and normal cervical tissue-derived MSCs (NCx-MSCs). We also analyzed their immunosuppressive capacity to decrease proliferation, activation and effector cytotoxic T (CD8+) lymphocyte function through the generation of adenosine (Ado). We detected that CeCa-MSCs express higher levels of CD39 and CD73 ectonucleotidases in cell membranes compared to NCx-MSCs, and that this feature was associated with the ability to strongly suppress the proliferation, activation and effector functions of cytotoxic T-cells through the generation of large amounts of Ado from the hydrolysis of ATP, ADP and AMP nucleotides. This study suggests that CeCa-MSCs play an important role in the suppression of the anti-tumor immune response in CeCa through the purinergic pathway.

  9. Genome-Wide Analysis of Corynespora cassiicola Leaf Fall Disease Putative Effectors.

    Science.gov (United States)

    Lopez, David; Ribeiro, Sébastien; Label, Philippe; Fumanal, Boris; Venisse, Jean-Stéphane; Kohler, Annegret; de Oliveira, Ricardo R; Labutti, Kurt; Lipzen, Anna; Lail, Kathleen; Bauer, Diane; Ohm, Robin A; Barry, Kerrie W; Spatafora, Joseph; Grigoriev, Igor V; Martin, Francis M; Pujade-Renaud, Valérie

    2018-01-01

    Corynespora cassiicola is an Ascomycetes fungus with a broad host range and diverse life styles. Mostly known as a necrotrophic plant pathogen, it has also been associated with rare cases of human infection. In the rubber tree, this fungus causes the Corynespora leaf fall (CLF) disease, which increasingly affects natural rubber production in Asia and Africa. It has also been found as an endophyte in South American rubber plantations where no CLF outbreak has yet occurred. The C. cassiicola species is genetically highly diverse, but no clear relationship has been evidenced between phylogenetic lineage and pathogenicity. Cassiicolin, a small glycosylated secreted protein effector, is thought to be involved in the necrotrophic interaction with the rubber tree but some virulent C. cassiicola isolates do not have a cassiicolin gene. This study set out to identify other putative effectors involved in CLF. The genome of a highly virulent C. cassiicola isolate from the rubber tree (CCP) was sequenced and assembled. In silico prediction revealed 2870 putative effectors, comprising CAZymes, lipases, peptidases, secreted proteins and enzymes associated with secondary metabolism. Comparison with the genomes of 44 other fungal species, focusing on effector content, revealed a striking proximity with phylogenetically unrelated species ( Colletotrichum acutatum, Colletotrichum gloesporioides, Fusarium oxysporum, nectria hematococca , and Botrosphaeria dothidea ) sharing life style plasticity and broad host range. Candidate effectors involved in the compatible interaction with the rubber tree were identified by transcriptomic analysis. Differentially expressed genes included 92 putative effectors, among which cassiicolin and two other secreted singleton proteins. Finally, the genomes of 35 C. cassiicola isolates representing the genetic diversity of the species were sequenced and assembled, and putative effectors identified. At the intraspecific level, effector

  10. Genome-Wide Analysis of Corynespora cassiicola Leaf Fall Disease Putative Effectors

    Directory of Open Access Journals (Sweden)

    David Lopez

    2018-03-01

    Full Text Available Corynespora cassiicola is an Ascomycetes fungus with a broad host range and diverse life styles. Mostly known as a necrotrophic plant pathogen, it has also been associated with rare cases of human infection. In the rubber tree, this fungus causes the Corynespora leaf fall (CLF disease, which increasingly affects natural rubber production in Asia and Africa. It has also been found as an endophyte in South American rubber plantations where no CLF outbreak has yet occurred. The C. cassiicola species is genetically highly diverse, but no clear relationship has been evidenced between phylogenetic lineage and pathogenicity. Cassiicolin, a small glycosylated secreted protein effector, is thought to be involved in the necrotrophic interaction with the rubber tree but some virulent C. cassiicola isolates do not have a cassiicolin gene. This study set out to identify other putative effectors involved in CLF. The genome of a highly virulent C. cassiicola isolate from the rubber tree (CCP was sequenced and assembled. In silico prediction revealed 2870 putative effectors, comprising CAZymes, lipases, peptidases, secreted proteins and enzymes associated with secondary metabolism. Comparison with the genomes of 44 other fungal species, focusing on effector content, revealed a striking proximity with phylogenetically unrelated species (Colletotrichum acutatum, Colletotrichum gloesporioides, Fusarium oxysporum, nectria hematococca, and Botrosphaeria dothidea sharing life style plasticity and broad host range. Candidate effectors involved in the compatible interaction with the rubber tree were identified by transcriptomic analysis. Differentially expressed genes included 92 putative effectors, among which cassiicolin and two other secreted singleton proteins. Finally, the genomes of 35 C. cassiicola isolates representing the genetic diversity of the species were sequenced and assembled, and putative effectors identified. At the intraspecific level, effector

  11. A case repot of Merkel cell carcinoma on chronic lymphocytic leukemia: differential diagnosis of coexisting lymphadenopathy and indications for early aggressive treatment

    International Nuclear Information System (INIS)

    Papageorgiou, KI; Kaniorou-Larai, MG

    2005-01-01

    Chronic lymphocytic leukemia (CLL) is a monoclonal disorder, characterized by a progressive proliferation of functionally incompetent B lymphocytes. There is increased evidence of association between CLL and skin cancers, including the uncommon Merkel cell carcinoma (MCC). A case report of an 84-year old male, who presented with an aggressively recurrent form of MCC on the lower lip, on the background of an 8-year history of untreated CLL. During the recurrences of MCC, coexisting regional lymphadenopathy, posed a problem in the differential diagnosis and treatment of lymph node involvement. Histopathology and immunoistochemistry showed that submandibular lymphadenopathy coexisting with the second recurrence of MCC, was due to B-cell small lymphocytic lymphoma. The subsequent and more aggressive recurrence of the skin tumor had involved the superficial and deep cervical lymph nodes. Surgical excision followed by involved field radiation therapy has been proven effective for both malignancies. MCC has a high incidence of regional lymphadenopathy at presentation (12–45%) and even when it arises on the background of chronic leucemia, lymphadenopathy at presentation should be managed agressively with elective lymph node dissection. We overview the postulated correlation between Merkel tumor and CCL, the differential diagnosis of regional lymphadenopathy during the recurrences of the skin tumor and the strategies of treatment

  12. The fourth dimension in immunological space: how the struggle for nutrients selects high-affinity lymphocytes.

    Science.gov (United States)

    Wensveen, Felix M; van Gisbergen, Klaas P J M; Eldering, Eric

    2012-09-01

    Lymphocyte activation via the antigen receptor is associated with radical shifts in metabolism and changes in requirements for nutrients and cytokines. Concomitantly, drastic changes occur in the expression of pro-and anti-apoptotic proteins that alter the sensitivity of lymphocytes to limiting concentrations of key survival factors. Antigen affinity is a primary determinant for the capacity of activated lymphocytes to access these vital resources. The shift in metabolic needs and the variable access to key survival factors is used by the immune system to eliminate activated low-affinity cells and to generate an optimal high-affinity response. In this review, we focus on the control of apoptosis regulators in activated lymphocytes by nutrients, cytokines, and costimulation. We propose that the struggle among individual clones that leads to the formation of high-affinity effector cell populations is in effect an 'invisible' fourth signal required for effective immune responses. © 2012 John Wiley & Sons A/S.

  13. Studies of lymphocyte growth and differentiation. Progress report, September 1, 1975--July 31, 1976

    Energy Technology Data Exchange (ETDEWEB)

    Rubin, A.D.

    1976-01-01

    Studies were continued on ribonuclear protein synthesis and the assembly of ribosomes in resting and stimulated lymphocytes. We demonstrated the interdependency of protein synthesis and RNA synthesis in the formation and processing of nascent ribonuclear protein particles. We further explored lymphocyte nuclei in a cell-free system. By isolating lymphocyte chromatin we showed a direct effect of PHA on the ability of this nuclear structure to incorporate radioactivity into acid precipitable RNA. We returned to our previous studies on the delayed response of chronic lymphocytic leukemia (CLL) lymphocytes to PHA. We traced this alternate response identifying it as a characteristic of the CLL cell. The evidence questioned the generally accepted conclusion that CLL represents a B cell malignancy. We went on further to describe delayed reacting lymphocytes in the circulation of patients with nodular lymphoma and acute lymphoblastic leukemia (ALL). The ALL, unlike the lymphoma and CLL cells, showed a normal magnitude of response, even though it was delayed. We described the technique which might be employed as a diagnostic test for detecting abnormal lymphocytes in patients with lymphocytic lymphoma and leukemia and could help distinguish these diseases from benign lymphoid hyperplasia and other forms of non-lymphocytic leukemia.

  14. Allergic contact dermatitis: A commentary on the relationship between T lymphocytes and skin sensitising potency

    International Nuclear Information System (INIS)

    Kimber, Ian; Maxwell, Gavin; Gilmour, Nicky; Dearman, Rebecca J.; Friedmann, Peter S.; Martin, Stefan F.

    2012-01-01

    T lymphocytes mediate skin sensitisation and allergic contact dermatitis. Not unexpectedly, therefore, there is considerable interest in the use of T lymphocyte-based assays as alternative strategies for the identification of skin sensitising chemicals. However, in addition to accurate identification of hazards the development of effective risk assessments requires that information is available about the relative skin sensitising potency of contact allergens. The purpose of this article is to consider the relationships that exist between the characteristics of T lymphocyte responses to contact allergens and the effectiveness/potency of sensitisation. We propose that there are 3 aspects of T lymphocyte responses that have the potential to impact on the potency of sensitisation. These are: (a) the magnitude of response, and in particular the vigour and duration of proliferation and the clonal expansion of allergen-reactive T lymphocytes, (b) the quality of response, including the balance achieved between effector and regulatory cells, and (c) the breadth of response and the clonal diversity of T lymphocyte responses. A case is made that there may be opportunities to exploit an understanding of T lymphocyte responses to contact allergens to develop novel paradigms for predicting skin sensitising potency and new approaches to risk assessment.

  15. The Orphan G Protein-coupled Receptor GPR17 Negatively Regulates Oligodendrocyte Differentiation via Gαi/o and Its Downstream Effector Molecules.

    Science.gov (United States)

    Simon, Katharina; Hennen, Stephanie; Merten, Nicole; Blättermann, Stefanie; Gillard, Michel; Kostenis, Evi; Gomeza, Jesus

    2016-01-08

    Recent studies have recognized G protein-coupled receptors as important regulators of oligodendrocyte development. GPR17, in particular, is an orphan G protein-coupled receptor that has been identified as oligodendroglial maturation inhibitor because its stimulation arrests primary mouse oligodendrocytes at a less differentiated stage. However, the intracellular signaling effectors transducing its activation remain poorly understood. Here, we use Oli-neu cells, an immortalized cell line derived from primary murine oligodendrocytes, and primary rat oligodendrocyte cultures as model systems to identify molecular targets that link cell surface GPR17 to oligodendrocyte maturation blockade. We demonstrate that stimulation of GPR17 by the small molecule agonist MDL29,951 (2-carboxy-4,6-dichloro-1H-indole-3-propionic acid) decreases myelin basic protein expression levels mainly by triggering the Gαi/o signaling pathway, which in turn leads to reduced activity of the downstream cascade adenylyl cyclase-cAMP-PKA-cAMP response element-binding protein (CREB). In addition, we show that GPR17 activation also diminishes myelin basic protein abundance by lessening stimulation of the exchange protein directly activated by cAMP (EPAC), thus uncovering a previously unrecognized role for EPAC to regulate oligodendrocyte differentiation. Together, our data establish PKA and EPAC as key downstream effectors of GPR17 that inhibit oligodendrocyte maturation. We envisage that treatments augmenting PKA and/or EPAC activity represent a beneficial approach for therapeutic enhancement of remyelination in those demyelinating diseases where GPR17 is highly expressed, such as multiple sclerosis. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  16. Radioiodine-induced changes in lymphocyte subsets in patients with differentiated thyroid carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Tofani, A.; Sciuto, R.; Cioffi, R.P.; Pasqualoni, R.; Rea, S.; Festa, A.; Maini, C.L. [Department of Nuclear Medicine, Regina Elena Cancer Institute, Rome (Italy); Gandolfo, G.M.; Arista, M.C. [Department of Clinical Pathology, Regina Elena Cancer Institute, Rome (Italy)

    1999-08-01

    This study evaluated changes in lymphocyte subsets in patients with thyroid carcinoma who received iodine-131 for diagnostic and therapeutic purposes. Twenty thyroid cancer patients were entered in the study after total thyroidectomy: ten patients (group A) underwent whole-body scintigraphy with 185 MBq of {sup 131}I and the other ten (group B) received 3700 MBq of {sup 131}I therapy. All patients were in a hypothyroid state at the time of administration of {sup 131}I and started l-thyroxine 150 {mu}g/day 3 days after {sup 131}I administration. Free and bound triiodothyronine and thyroxine, thyroid-stimulating hormone, thyroglobulin, thyroglobulin antibodies, thyroid peroxidase/microsomal antibodies, white blood cell, lymphocyte counts and lymphocyte subsets were serially determined at baseline and at days 2, 7, 15, 30 and 60 after {sup 131}I administration. Twenty healthy age- and sex-matched individuals were used as a reference population for lymphocyte subset values. In group A only a reduction in NK cells at days 7 (P=0.043) and 15 (P=0.037) was observed. In group B, patients showed a delayed reduction in the total lymphocyte count at days 15, 30 and 60 (P=0.008, 0.004 and 0.018, respectively), and a decrease in B cells throughout the study (at days 7, 15, 30 and 60: P=0.006, 0.0017, 0.0017 and 0.0017 respectively). A transient decrease in NK cells was observed at days 15 (P=0.025) and 30 (P=0.008). Among T cells, the helper phenotype (CD4+) was mainly affected, resulting in a reduction in the CD4+/CD8+ ratio at day 60 (P=0.046). Comparing the two groups, the numbers of B lymphocytes at day 30 (P=0.023) and NK cells at days 2 (P=0.037) and 30 (P=0.023) were significantly lower in group B. Neither group showed any clinical sign of immunosuppression during the follow-up period. In patients with thyroid cancer the sensitivity of lymphocytes to the effects of {sup 131}I administered for diagnostic or therapeutic purposes depends upon lymphocyte phenotype and {sup

  17. Lymphocytic infiltration of bladder after local cellular immunotherapy.

    Science.gov (United States)

    Ingram, M; Bishai, M B; Techy, G B; Narayan, K S; Saroufeem, R; Yazan, O; Marshall, C E

    2000-01-01

    This is a case report of a patient who received cellular immunotherapy, in the form of local injections of autologous stimulated lymphocytes (ASL) into individual tumors in the urinary bladder. A major consideration in cellular immunotherapy being the ability of immune cells to reach all target areas, we hypothesized that direct delivery of effector cells into individual bladder tumors might assure such access. ASL were generated by exposing the patient's PBL to phytohemagglutinin and culturing them in the presence of IL-2 to expand the population. ASL were injected into the base of individual bladder tumors three times at intervals of 3 weeks. The patient died of a myocardial infarct, unrelated to cell therapy, 20 days after the third injection. An autopsy was performed. Histological sections of the bladder showed extensive lymphocytic infiltration of virtually the entire organ. No conclusions about the therapeutic efficacy of local immunotherapy using ASL are possible. Nevertheless, the observations reported, taken together with reports of therapeutic efficacy of other immunotherapy regimens in the management of bladder cancer, suggest that ready access of stimulated lymphocytes to all regions of the organ may account, in part, for the relatively high rate of therapeutic success reported for various immunotherapy regimens for this malignancy.

  18. Transcriptome analysis of the fungal pathogen Fusarium oxysporum f. sp. medicaginis during colonisation of resistant and susceptible Medicago truncatula hosts identifies differential pathogenicity profiles and novel candidate effectors.

    Science.gov (United States)

    Thatcher, Louise F; Williams, Angela H; Garg, Gagan; Buck, Sally-Anne G; Singh, Karam B

    2016-11-03

    Pathogenic members of the Fusarium oxysporum species complex are responsible for vascular wilt disease on many important crops including legumes, where they can be one of the most destructive disease causing necrotrophic fungi. We previously developed a model legume-infecting pathosystem based on the reference legume Medicago truncatula and a pathogenic F. oxysporum forma specialis (f. sp.) medicaginis (Fom). To dissect the molecular pathogenicity arsenal used by this root-infecting pathogen, we sequenced its transcriptome during infection of a susceptible and resistant host accession. High coverage RNA-Seq of Fom infected root samples harvested from susceptible (DZA315) or resistant (A17) M. truncatula seedlings at early or later stages of infection (2 or 7 days post infection (dpi)) and from vegetative (in vitro) samples facilitated the identification of unique and overlapping sets of in planta differentially expressed genes. This included enrichment, particularly in DZA315 in planta up-regulated datasets, for proteins associated with sugar, protein and plant cell wall metabolism, membrane transport, nutrient uptake and oxidative processes. Genes encoding effector-like proteins were identified, including homologues of the F. oxysporum f. sp. lycopersici Secreted In Xylem (SIX) proteins, and several novel candidate effectors based on predicted secretion, small protein size and high in-planta induced expression. The majority of the effector candidates contain no known protein domains but do share high similarity to predicted proteins predominantly from other F. oxysporum ff. spp. as well as other Fusaria (F. solani, F. fujikori, F. verticilloides, F. graminearum and F. pseudograminearum), and from another wilt pathogen of the same class, a Verticillium species. Overall, this suggests these novel effector candidates may play important roles in Fusaria and wilt pathogen virulence. Combining high coverage in planta RNA-Seq with knowledge of fungal pathogenicity

  19. Three Antagonistic Cyclic di-GMP-Catabolizing Enzymes Promote Differential Dot/Icm Effector Delivery and Intracellular Survival at the Early Steps of Legionella pneumophila Infection

    Science.gov (United States)

    Allombert, Julie; Lazzaroni, Jean-Claude; Baïlo, Nathalie; Gilbert, Christophe; Charpentier, Xavier; Doublet, Patricia

    2014-01-01

    Legionella pneumophila is an intracellular pathogen which replicates within protozoan cells and can accidently infect alveolar macrophages, causing an acute pneumonia in humans. The second messenger cyclic di-GMP (c-di-GMP) has been shown to play key roles in the regulation of various bacterial processes, including virulence. While investigating the function of the 22 potential c-di-GMP-metabolizing enzymes of the L. pneumophila Lens strain, we found three that directly contribute to its ability to infect both protozoan and mammalian cells. These three enzymes display diguanylate cyclase (Lpl0780), phosphodiesterase (Lpl1118), and bifunctional diguanylate cyclase/phosphodiesterase (Lpl0922) activities, which are all required for the survival and intracellular replication of L. pneumophila. Mutants with deletions of the corresponding genes are efficiently taken up by phagocytic cells but are partially defective for the escape of the Legionella-containing vacuole (LCV) from the host degradative endocytic pathway and result in lower survival. In addition, Lpl1118 is required for efficient endoplasmic reticulum recruitment to the LCV. Trafficking and biogenesis of the LCV are dependent upon the orchestrated actions of several type 4 secretion system Dot/Icm effectors proteins, which exhibit differentially altered translocation in the three mutants. While translocation of some effectors remained unchanged, others appeared over- and undertranslocated. A general translocation offset of the large repertoire of Dot/Icm effectors may be responsible for the observed defects in the trafficking and biogenesis of the LCV. Our results suggest that L. pneumophila uses cyclic di-GMP signaling to fine-tune effector delivery and ensure effective evasion of the host degradative pathways and establishment of a replicative vacuole. PMID:24379287

  20. Impact of chronic lymphocytic thyroiditis on the prognosis of differentiated thyroid cancer

    International Nuclear Information System (INIS)

    Boughattas, S.; Chatti, K.; Degdegui, M.; Hasine, H.

    2004-01-01

    Full text: The association of chronic lymphocytic thyroiditis (CLT) and differentiated thyroid cancer, and its prognosis significance remain controversial. We investigate the prognosis impact of this association by reviewing our series of patients being followed for differentiated thyroid cancer (DTC) at the department of nuclear medicine of Sahloul. Among the 350 patients followed in our department, 30 (8.5%) had histologically proved CLT, with infiltration of the non- tumoral thyroid tissue. A second group of 60 patients (without evidence of lymphocytic infiltration) was selected randomly and used as controls. The median of follow-up for these two groups was 4 years. The frequency of papillary thyroid cancer was significantly higher in the group with CTL (90% vs 74%; p=0.05). The larger diameter of the tumor didn't differ significantly (p= 0.36) between the group with TLC (mean=2.7; SD=1.98) and the control group 3.08 (SD=1.66). There was also no significant difference in capsular infiltration (37% vs 36%; p=0.96), nodal metastases (47% vs 43%; p=0.74), multicentric tumors (37% vs 38%; p=0.99) and bilateral tumors (20% vs 22%; p=0.9). At initial presentation, distant metastases were less frequent in patients with coexisting CLT and DTC (3% vs 12%, p<1%). Nevertheless, if we consider only patients with papillary thyroid cancer, the difference was not statistically significant (0% vs 6%; p=0.23). During the follow-up (mean 4 years), there was no significant difference in nodal relapse (20% vs 8% p=0.1), and distant metastasis (6% vs 3%: p=0.45). No death was noted in the first group, and two were observed in the second (patients with follicular thyroid cancer). The most striking result of this study is the total absence of significant impact of CLT on the prognosis of DTC. Our results seem to be on opposite to those of the majority of authors, underlying the complexity of this entity. We think that some factors specific to our population (iodine diet, ethnical

  1. A ROLE FOR INTERLEUKIN 8 IN DIRECT REGULATION OF T CELL FUNCTIONAL ACTIVITY

    Directory of Open Access Journals (Sweden)

    M. E. Meniailo

    2017-01-01

    Full Text Available CD3+T lymphocytes were isolated from normal donors by positive magnetic separation. Activation of the T cells with particles conjugated with antibodies to CD3, СD28 and СD2 molecules led to substantial increase in T cell production of interleukin-8 (IL-8. An interleukin-8 receptor (CXCR1, CD181 was initially expressed in 13.3% of T lymphocytes. Activation of T lymphocytes resulted into a detectable increase of CD181+ cell number among CD4+ naïve cells and CD4+ terminally-differentiated effector cells, and, conversely, into decrease of their number among CD4+ effector memory cells. Activation of T lymphocytes was assessed by membrane expression of CD25 molecule (receptor for IL-2. IL-8 (0.01-10.0 ng/ml was shown to markedly reduce activation of both CD4- and CD4+ effector memory T cells, as well as terminallydifferentiated T effectors, without significantly affecting activation of naive T lymphocytes and central memory T cells. IL-8 noticeably increased IL-2 production by activated Т cells, caused a reduced IL-10 production, and did not significantly affect the secretion of IFNγ and IL-4. The data obtained suggest a significance of IL-8 for direct regulation of adaptive T cell responses.

  2. Defective immunoregulatory T-cell function in chronic lymphocytic leukemia

    International Nuclear Information System (INIS)

    Han, T.; Ozer, H.; Henderson, E.S.; Dadey, B.; Nussbaum-Blumenson, A.; Barcos, M.

    1981-01-01

    Chronic lymphocytic leukemia (CLL) of B-cell origin results in the malignant proliferation of small immunoglobulin-bearing lymphocytes. There is currently a controversy in the literature regarding both the ability of this leukemic population to differentiate into mature plasma cells, as well as the ability of apparently normal T cells from these patients to regulate allogeneic B-cell differentiation. In the present study we have examined the lymphocytes of CLL patients in various clinical stages of their disease and with different surface phenotypes of their leukemic B-cell population. Our results show that leukemic CLL B cells from all 20 patients (including one patient with a monoclonal IgM paraprotein and another with a monoclonal IgG paraprotein) are incapable of further differentiation even in the absence of suppressor T cells and the presence of helper T lymphocytes. This lack of capacity to differentiate is unaffected by clinical stage, by therapy, or by the phenotype of the malignant population. Since the leukemic B population did not suppress normal allogeneic B-cell differentiation, the maturation deficit is evidently intrinsic to the leukemic clone rather than a result of activity of non-T suppressor cells. T helper function was also variably depressed in the blood of some patients with CLL, and this depression did not correlate with clinical stage, with therapy, or with the degree of lymphocytosis. Dysfunction of radiosensitive T suppressor cells was found to be the most consistent regulatory deficit of CLL T cells. Each of 11 patients whose leukemic cell population was of the μdelta, μα, or μ phenotype had both helper and suppressor cell defects

  3. Differentiation of human B lymphocyte subpopulations induced by an alloreactive helper T-cell clone

    International Nuclear Information System (INIS)

    Anderson, S.J.; Hummell, D.S.; Lawton, A.R.

    1988-01-01

    We have used cloned alloreactive helper T cells to determine if direct T cell-B cell interaction can induce differentiation of human peripheral blood B cells which do not respond to pokeweed mitogen (PWM). T-cell clone 2F8 was derived from a one-way mixed lymphocyte reaction. 2F8 cells are T3+T4+T8-IL-2R+ and proliferate in response to irradiated stimulator cells, but not autologous cells, in the absence of exogenous interleukin-2. 2F8 cells provide allospecific help for polyclonal proliferation and differentiation of B cells in the absence of any other stimulus. The magnitude of this response is comparable to that of the response of the same B cells to PWM and fresh autologous T cells. 2F8 cells could also provide nonspecific help for unrelated donor B cells in the presence of PWM, with no requirement for costimulation by irradiated stimulator cells. Allospecific stimulation of B cells was completely inhibited by antibodies to class II major histocompatibility complex (MHC) framework determinants and was abrogated by 1000-rad irradiation. Cloned 2F8 T cells stimulated differentiation of both small, high-density B cells and larger B cells, generating up to 30% plasma cells with either fraction. B cells forming rosettes with mouse erythrocytes were also induced to differentiate by the helper T cell clone. As found previously, neither small, high-density B cells nor mouse rosette+ B cells responded well to PWM. Direct interaction with allospecific T cells induces differentiation of a broader spectrum of B cells than soluble growth and differentiation factors in conjunction with polyclonal activators such as PWM and protein A containing staphylococci

  4. Differential expression of candidate salivary effector proteins in field collections of Hessian fly, Mayetiola destructor

    Science.gov (United States)

    Johnson, A J; Shukle, R H; Chen, M-S; Srivastava, S; Subramanyam, S; Schemerhorn, B J; Weintraub, P G; Abdel Moniem, H E M; Flanders, K L; Buntin, G D; Williams, C E

    2015-01-01

    Evidence is emerging that some proteins secreted by gall-forming parasites of plants act as effectors responsible for systemic changes in the host plant, such as galling and nutrient tissue formation. A large number of secreted salivary gland proteins (SSGPs) that are the putative effectors responsible for the physiological changes elicited in susceptible seedling wheat by Hessian fly, Mayetiola destructor (Say), larvae have been documented. However, how the genes encoding these candidate effectors might respond under field conditions is unknown. The goal of this study was to use microarray analysis to investigate variation in SSGP transcript abundance amongst field collections from different geographical regions (southeastern USA, central USA, and the Middle East). Results revealed significant variation in SSGP transcript abundance amongst the field collections studied. The field collections separated into three distinct groups that corresponded to the wheat classes grown in the different geographical regions as well as to recently described Hessian fly populations. These data support previous reports correlating Hessian fly population structure with micropopulation differences owing to agro-ecosystem parameters such as cultivation of regionally adapted wheat varieties, deployment of resistance genes and variation in climatic conditions. PMID:25528896

  5. Plant parasitic nematode effectors target host defence and nuclear functions to establish feeding cells

    Directory of Open Access Journals (Sweden)

    Michaël eQuentin

    2013-03-01

    Full Text Available Plant parasitic nematodes are microscopic worms, the most damaging species of which have adopted a sedentary lifestyle within their hosts. These obligate endoparasites have a biotrophic relationship with plants, in which they induce the differentiation of root cells into hypertrophied, multinucleate feeding cells. Effectors synthesised in the oesophageal glands of the nematode are injected into the plant cells via the syringe-like stylet and play a key role in manipulating the host machinery. The establishment of specialized feeding cells requires these effectors to modulate many aspects of plant cell morphogenesis and physiology, including defence responses. This cell reprogramming requires changes to host nuclear processes. Some proteins encoded by parasitism genes target host nuclei. Several of these proteins were immunolocalised within feeding cell nuclei or shown to interact with host nuclear proteins. Comparative genomics and functional analyses are gradually revealing the roles of nematode effectors. We describe here these effectors and their hypothesised roles in the unique feeding behaviour of these pests.

  6. Differential modulation of plant immune responses by diverse members of the Pseudomonas savastanoi pv. savastanoi HopAF type III effector family.

    Science.gov (United States)

    Castañeda-Ojeda, M Pilar; López-Solanilla, Emilia; Ramos, Cayo

    2017-06-01

    The Pseudomonas savastanoi pv. savastanoi NCPPB 3335 type III secretion system (T3SS) effector repertoire includes 33 candidates, seven of which translocate into host cells and interfere with plant defences. The present study was performed to investigate the co-existence of both plasmid- and chromosomal-encoded members of the HopAF effector family, HopAF1-1 and HopAF1-2, respectively, in the genome of NCPPB 3335. Here, we show that the HopAF1 paralogues are widely distributed in the Pseudomonas syringae complex, where HopAF1-1 is most similar to the homologues encoded by other P. syringae pathovars infecting woody hosts that belong to phylogroups 1 and 3. We show that the expression of both HopAF1-1 and HopAF-2 is transcriptionally dependent on HrpL and demonstrate their delivery into Nicotiana tabacum leaves. Although the heterologous delivery of either HopAF1-1 or HopAF1-2 significantly suppressed the production of defence-associated reactive oxygen species levels, only HopAF1-2 reduced the levels of callose deposition. Moreover, the expression of HopAF1-2 by functionally effectorless P. syringae pv. tomato DC3000D28E completely inhibited the hypersensitive response in tobacco and significantly increased the competitiveness of the strain in Nicotiana benthamiana. Despite their functional differences, subcellular localization studies reveal that green fluorescent protein (GFP) fusions to either HopAF1-1 or HopAF1-2 are targeted to the plasma membrane when they are expressed in plant cells, a process that is completely dependent on the integrity of their N-myristoylation motif. Our results further support the notion that highly similar T3SS effectors might differentially interact with diverse plant targets, even when they co-localize in the same cell compartment. © 2016 BSPP AND JOHN WILEY & SONS LTD.

  7. Oomycetes, effectors, and all that jazz.

    Science.gov (United States)

    Bozkurt, Tolga O; Schornack, Sebastian; Banfield, Mark J; Kamoun, Sophien

    2012-08-01

    Plant pathogenic oomycetes secrete a diverse repertoire of effector proteins that modulate host innate immunity and enable parasitic infection. Understanding how effectors evolve, translocate and traffic inside host cells, and perturb host processes are major themes in the study of oomycete-plant interactions. The last year has seen important progress in the study of oomycete effectors with, notably, the elucidation of the 3D structures of five RXLR effectors, and novel insights into how cytoplasmic effectors subvert host cells. In this review, we discuss these and other recent advances and highlight the most important open questions in oomycete effector biology. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Differentiation and functional maturation of bone marrow-derived intestinal epithelial T cells expressing membrane T cell receptor in athymic radiation chimeras

    International Nuclear Information System (INIS)

    Mosley, R.L.; Styre, D.; Klein, J.R.

    1990-01-01

    The thymus dependency of murine intestinal intraepithelial lymphocytes (IEL) was studied in an athymic F1----parent radiation chimera model. IEL, although not splenic or lymph node lymphocytes, from athymic chimeras displayed normal levels of cells bearing the class-specific T cell Ag, CD4 and CD8; the TCR-associated molecule, CD3; and the Thy-1 Ag. Moreover, two-color flow cytometric analyses of IEL from athymic mice demonstrated regulated expression of T cell Ag characteristic of IEL subset populations from thymus-bearing mice. In immunoprecipitation experiments, surface TCR-alpha beta or TCR-gamma delta were expressed on IEL, although not on splenic lymphocytes, from athymic chimeras. That IEL from athymic chimeras constituted a population of functionally mature effector cells activated in situ, similar to IEL from thymus-bearing mice, was demonstrated by the presence of CD3-mediated lytic activity of athymic lethally irradiated bone marrow reconstituted IEL. These data provide compelling evidence that intestinal T cells do not require thymic influence for maturation and development, and demonstrate that the microenvironment of the intestinal epithelium is uniquely adapted to regulate IEL differentiation

  9. Alterations in Sensitivity to Estrogen, Dihydrotestosterone, and Xenogens in B-Lymphocytes from Children with Autism Spectrum Disorder and Their Unaffected Twins/Siblings

    Directory of Open Access Journals (Sweden)

    Martyn A. Sharpe

    2013-01-01

    Full Text Available It has been postulated that androgen overexposure in a susceptible person leads to excessive brain masculinization and the autism spectrum disorder (ASD phenotype. In this study, the responses to estradiol (E2, dihydrotestosterone (DHT, and dichlorodiphenyldichloroethylene (DDE on B-lymphocytes from ASD subjects and controls are compared. B cells were obtained from 11 ASD subjects, their unaffected fraternal twins, and nontwin siblings. Controls were obtained from a different cell bank. Lactate dehydrogenase (LDH and sodium 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl-2H-tetrazolium-5-carboxanilide (XTT reduction levels were measured after incubation with different concentrations of E2, DHT, and DDE. XTT/LDH ratio, representative of mitochondria number per cell, was calculated. E2, DHT, and DDE all cause “U”-shaped growth curves, as measured by LDH levels. ASD B cells show less growth depression compared to siblings and controls (P<0.01. They also have reduced XTT/LDH ratios (P<0.01 when compared to external controls, whereas siblings had values of XTT/LDH between ASD and external controls. B-lymphocytes from people with ASD exhibit a differential response to E2, DHT, and hormone disruptors in regard to cell growth and mitochondrial upregulation when compared to non-ASD siblings and external controls. Specifically, ASD B-lymphocytes show significantly less growth depression and less mitochondrial upregulation when exposed to these effectors. A mitochondrial deficit in ASD individuals is implied.

  10. Dysregulation of T lymphocyte proliferative responses in autoimmunity.

    Directory of Open Access Journals (Sweden)

    Sydney K Elizer

    Full Text Available T cells are critically dependent on cellular proliferation in order to carry out their effector functions. Autoimmune strains are commonly thought to have uncontrolled T cell proliferation; however, in the murine model of autoimmune diabetes, hypo-proliferation of T cells leading to defective AICD was previously uncovered. We now determine whether lupus prone murine strains are similarly hyporesponsive. Upon extensive characterization of T lymphocyte activation, we have observed a common feature of CD4 T cell activation shared among three autoimmune strains-NOD, MRL, and NZBxNZW F1s. When stimulated with a polyclonal mitogen, CD4 T cells demonstrate arrested cell division and diminished dose responsiveness as compared to the non-autoimmune strain C57BL/6, a phenotype we further traced to a reliance on B cell mediated costimulation, which underscores the success of B cell directed immune therapies in preventing T cell mediated tissue injury. In turn, the diminished proliferative capacity of these CD4 T cells lead to a decreased, but activation appropriate, susceptibility to activation induced cell death. A similar decrement in stimulation response was observed in the CD8 compartment of NOD mice; NOD CD8 T cells were distinguished from lupus prone strains by a diminished dose-responsiveness to anti-CD3 mediated stimulation. This distinction may explain the differential pathogenetic pathways activated in diabetes and lupus prone murine strains.

  11. Decreased numbers of CD4+ naive and effector memory T cells, and CD8+ naïve T cells, are associated with trichloroethylene exposure

    Directory of Open Access Journals (Sweden)

    H Dean eHosgood

    2012-01-01

    Full Text Available Trichloroethylene (TCE is a volatile chlorinated organic compound that is commonly used as a solvent for lipophilic compounds. Although recognized as an animal carcinogen, TCE’s carcinogenic potential in humans is still uncertain. We have carried out a cross-sectional study of 80 workers exposed to TCE and 96 unexposed controls matched on age and sex in Guangdong, China to study TCE’s early biologic effects. We previously reported that the total lymphocyte count and each of the major lymphocyte subsets (i.e., CD4+ T cells, CD8+ T cells, natural killer (NK cells, and B cells were decreased in TCE-exposed workers compared to controls, suggesting a selective effect on lymphoid progenitors and/or lymphocyte survival. To explore which T lymphocyte subsets are affected, we investigated the effect of TCE exposure on the numbers of CD4+ naïve and memory T cells, CD8+ naïve and memory T cells, and regulatory T cells by FACS analysis. Linear regression of each subset was used to test for differences between exposed workers and controls adjusting for potential confounders. We observed that CD4+ and CD8+ naïve T cell counts were about 8% (p = 0.056 and 17% (p = 0.0002 lower, respectively, among exposed workers. CD4+ effector memory T cell counts were decreased by about 20% among TCE exposed workers compared to controls (p = 0.001. The selective targeting of TCE on CD8+ naïve and possibly CD4+ naive T cells, and CD4+ effector memory T cells, provide further insights into the immunosuppression-related response of human immune cells upon TCE exposure.

  12. Can Serum Neutrophil-to-Lymphocyte Ratio Be a Predictive Biomarker to Help Differentiate Active Chronic Otitis Media From Inactive Chronic Otitis Media?

    Science.gov (United States)

    Tansuker, Hasan Deniz; Eroğlu, Sinan; Yenigün, Alper; Taşkin, Ümit; Oktay, Mehmet Faruk

    2017-05-01

    The authors' aim was to investigate whether serum neutrophil to lymphocyte ratio might be used as a predictive biomarker to help differentiate active from inactive chronic otitis media (COM). Two hundred fifty-nine patients having inactive COM received tympanoplasty without mastoidectomy and were identified as Group 1. On the other hand, 254 patients having active COM received tympanoplasty with mastoidectomy and were identified as Group 2. Routine hemogram tests were performed preoperatively for both the groups. By performing a chart review, white blood cell count, red blood cell count, hemoglobin, hematocrit, platelet, and mean platelet volume values were compared between the groups in an age-matched and sex-matched manner. A total of 513 COM patients with age range of 7 to 65 years were included in the study. Two hundred seventy-five patients (53.6%) were male, 238 were (46.4%) female. Preoperatively both serum neutrophil and lymphocyte counts were significantly higher in Group 2 (P = 0.015 and P = 0.004, respectively). However, the neutrophil-to-lymphocyte ratios between the groups were not significantly different (P = 0.511). No statistically significant differences were identified from preoperative neutrophil-to-lymphocyte ratios between patients having active COM and inactive COM. Level NA.

  13. Cellular energy metabolism in T-lymphocytes.

    Science.gov (United States)

    Gaber, Timo; Strehl, Cindy; Sawitzki, Birgit; Hoff, Paula; Buttgereit, Frank

    2015-01-01

    Energy homeostasis is a hallmark of cell survival and maintenance of cell function. Here we focus on the impact of cellular energy metabolism on T-lymphocyte differentiation, activation, and function in health and disease. We describe the role of transcriptional and posttranscriptional regulation of lymphocyte metabolism on immune functions of T cells. We also summarize the current knowledge about T-lymphocyte adaptations to inflammation and hypoxia, and the impact on T-cell behavior of pathophysiological hypoxia (as found in tumor tissue, chronically inflamed joints in rheumatoid arthritis and during bone regeneration). A better understanding of the underlying mechanisms that control immune cell metabolism and immune response may provide therapeutic opportunities to alter the immune response under conditions of either immunosuppression or inflammation, potentially targeting infections, vaccine response, tumor surveillance, autoimmunity, and inflammatory disorders.

  14. Lymphocyte-based model systems for allergy research: a historic overview.

    Science.gov (United States)

    Neunkirchner, Alina; Schmetterer, Klaus G; Pickl, Winfried F

    2014-01-01

    During the last decades, a multitude of studies applying distinct in vitro and in vivo model systems have contributed greatly to our better understanding of the initiation and regulation of inflammatory processes leading to allergic diseases. Over the years, it has become evident that among lymphocytes, not only IgE-producing B cells and allergy-orchestrating CD4(+) helper cells but also cytotoxic CD8(+) T cells, γδ-T cells and innate lymphoid cells, as well as regulatory lymphocytes, might critically shape the immune response towards usually innocuous allergens. In this review, we provide a historic overview of pioneering work leading to the establishment of important lymphocyte-based model systems for allergy research. Moreover, we contrast the original findings with our currently more refined knowledge to appreciate the actual validity of the respective models and to reassess the conclusions obtained from them. Conflicting studies and interpretations are identified and discussed. The tables are intended to provide an easy overview of the field not only for scientists newly entering the field but also for the broader readership interested in updating their knowledge. Along those lines, herein we discuss in vitro and in vivo approaches to the investigation of lymphocyte effector cell activation, polarization and regulation, and describe depletion and adoptive transfer models along with gene knockout and transgenic (tg) methodologies. In addition, novel attempts to establish humanized T cell antigen receptor tg mouse models for allergy research are described and discussed. © 2014 S. Karger AG, Basel.

  15. Differential expression of the human thymosin-β4 gene in lymphocytes, macrophages, and granulocytes

    International Nuclear Information System (INIS)

    Gondo, H.; Kudo, J.; White, J.W.; Barr, C.; Selvanayagam, P.; Saunders, G.F.

    1987-01-01

    A cDNA clone encoding human thymosin-β 4 was isolated from a cDNA library prepared from peripheral blood leukocytes of a patient with acute lymphocytic leukemia. This clone contained the entire coding sequence of 43 amino acid residues of thymosin-β 4 and had an initiation codon and two termination codons. The amino acid and nucleotide sequences in the coding region were well conserved between rat and human. No signal peptide was found in the deduced protein sequence. Human thymosin-β 4 mRNA, approximately 830 nucleotides in length, was about 30 nucleotides larger than rat thymosin-β 4 mRNA. Expression of the human thymosin-β 4 gene in various primary myeloid and lymphoid malignant cells and in a few human hemopoietic cell lines was studied. Northern blot analyses of different neoplastic B lymphocytes revealed that steady state levels of thymosin-β 4 mRNA varied as a function of differentiation stage. Thymosin-β 4 mRNA levels were decreased in myeloma cells as are class II human leukocyte antigen, Fc receptor, and complement receptor, suggesting a relationship between thymosin-β 4 and the immune response. Treatment of THP-1 cells, a human monocytic cell line, with recombinant human interferon-γ reduced the levels of thymosin-β 4 mRNA. The pattern of thymosin-β 4 gene expression suggests that it may play a fundamental role in the host defense mechanism

  16. Differential association of GABAB receptors with their effector ion channels in Purkinje cells.

    Science.gov (United States)

    Luján, Rafael; Aguado, Carolina; Ciruela, Francisco; Cózar, Javier; Kleindienst, David; de la Ossa, Luis; Bettler, Bernhard; Wickman, Kevin; Watanabe, Masahiko; Shigemoto, Ryuichi; Fukazawa, Yugo

    2018-04-01

    Metabotropic GABA B receptors mediate slow inhibitory effects presynaptically and postsynaptically through the modulation of different effector signalling pathways. Here, we analysed the distribution of GABA B receptors using highly sensitive SDS-digested freeze-fracture replica labelling in mouse cerebellar Purkinje cells. Immunoreactivity for GABA B1 was observed on presynaptic and, more abundantly, on postsynaptic compartments, showing both scattered and clustered distribution patterns. Quantitative analysis of immunoparticles revealed a somato-dendritic gradient, with the density of immunoparticles increasing 26-fold from somata to dendritic spines. To understand the spatial relationship of GABA B receptors with two key effector ion channels, the G protein-gated inwardly rectifying K + (GIRK/Kir3) channel and the voltage-dependent Ca 2+ channel, biochemical and immunohistochemical approaches were performed. Co-immunoprecipitation analysis demonstrated that GABA B receptors co-assembled with GIRK and Ca V 2.1 channels in the cerebellum. Using double-labelling immunoelectron microscopic techniques, co-clustering between GABA B1 and GIRK2 was detected in dendritic spines, whereas they were mainly segregated in the dendritic shafts. In contrast, co-clustering of GABA B1 and Ca V 2.1 was detected in dendritic shafts but not spines. Presynaptically, although no significant co-clustering of GABA B1 and GIRK2 or Ca V 2.1 channels was detected, inter-cluster distance for GABA B1 and GIRK2 was significantly smaller in the active zone than in the dendritic shafts, and that for GABA B1 and Ca V 2.1 was significantly smaller in the active zone than in the dendritic shafts and spines. Thus, GABA B receptors are associated with GIRK and Ca V 2.1 channels in different subcellular compartments. These data provide a better framework for understanding the different roles played by GABA B receptors and their effector ion channels in the cerebellar network.

  17. To the nucleolar bodies (nucleoli) in cells of the lymphocytic lineage in patients suffering from B - chronic lymphocytic leukemia.

    Science.gov (United States)

    Smetana, K; Karban, J; Trneny, M

    2010-01-01

    The present study was undertaken to provide more information on nucleoli in lymphocytes of B - chronic lymphocytic leukemia. The computer assisted nucleolar and cytoplasmic RNA image densitometry, reflecting the nucleolar and cytoplasmic RNA concentration at the single cell level, demonstrated a remarkable stability during the differentiation and maturation of B- lymphocytes. In contrast, as it was expected, the nucleolar diameter during the lymphocytic development markedly decreased. Thus the nucleolar RNA content of leukemic B-lymphocytes was apparently related to the nucleolar size. In both immature and mature lymphocytes, the cytostatic treatment increased the incidence of micronucleoli, which represent the "inactive" type of nucleoli. However, the decreased values of the nucleolar diameter were statistically significant only in mature lymphocytes of treated patients. On the other hand, despite such observation, it must be mentioned that "large active" and "ring shaped resting" nucleoli were still present in immature and mature lymphocytes after the cytostatic therapy and such cells might represent a potential pool of proliferating cells. As it is generally accepted "large active nucleoli" with multiple fibrillar centers are known to be characteristic for proliferating cells. "Ring shaped resting nucleoli" are present in sleeping cells, which may be stimulated to return to the cell cycle and to proliferate again. In addition, the nucleolar RNA distribution also indicated that Gumprecht ghosts mostly originated from mature lymphocytes. Increased ratio of the nucleolar to cytoplasmic RNA density in Gumprecht ghosts or apoptotic cells and apoptotic bodies of the lymphocytic origin was related to the decreased cytoplasmic RNA concentration. The increased nucleolar size together with the markedly decreased cytoplasmic RNA concentration characteristic for Gumprecht ghosts just reflected the spreading of lymphocytes during smear preparations. In apoptotic cells or

  18. Lymphocyte subsets are influenced by positivity levels in healthy subjects before and after mild acute stress.

    Science.gov (United States)

    Caprara, Gian Vittorio; Nisini, Roberto; Castellani, Valeria; Vittorio, Pasquali; Alessandri, Guido; Vincenzo, Ziparo; Claudia, Ferlito; Valentina, Germano; Andrea, Picchianti Diamanti; Biondo, Michela Ileen; Milanetti, Francesca; Salerno, Gerardo; Vincenzo, Visco; Mario, Pietrosanti; Aniballi, Eros; Simonetta, Salemi; Angela, Santoni; D'Amelio, Raffaele

    2017-08-01

    In the current study, the possible association of positivity (POS), recently defined as general disposition to view life under positive outlook, with immune markers and post-stress modifications, was analyzed. Circulating lymphocyte subsets and serum cytokine levels were evaluated before and after a standard mild acute stress test, in 41 healthy students, previously selected by a questionnaire for their level of POS (high [POS-H] and low [POS-L]). The CD3 + and CD4 + cell frequency was higher in the POS-H students before and after acute stress. CD4 + subpopulation analysis revealed baseline higher terminally differentiated frequency in the POS-H, whereas higher effector memory frequency was present in the POS-L students. Moreover, the frequency of post-stress B cells was higher in the POS-H students. The mild-stress test was associated to an increase of the IL-10 mean values, while mean values of the other cytokines tested did not change significantly. It is tempting to speculate that IL-10 may work as biomarker of response to acute mild stress and that POS-H may be associated to a better capacity of the immune system to contrast the disturbing effects of mild acute stress. Yet further studies on lymphocyte subset absolute number and function of larger and different populations are needed to definitively prove these preliminary observations. Copyright © 2017 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

  19. Increased numbers of pre-existing memory CD8 T cells and decreased T-bet expression can restrain terminal differentiation of secondary effector and memory CD8 T cells1

    Science.gov (United States)

    Joshi, Nikhil S.; Cui, Weiguo; Dominguez, Claudia; Chen, Jonathan H.; Hand, Timothy W.; Kaech, Susan M.

    2011-01-01

    Memory CD8 T cells acquire TEM properties following reinfection, and may reach terminally differentiated, senescent states (“Hayflick limit”) after multiple infections. The signals controlling this process are not well understood, but we found that the degree of 2o effector and memory CD8 T cell differentiation was intimately linked to the amount of T-bet expressed upon reactivation and pre-existing memory CD8 T cell number (i.e., 1o memory CD8 T cell precursor frequency) present during secondary infection. Compared to naïve cells, memory CD8 T cells were predisposed towards terminal effector (TE) cell differentiation because they could immediately respond to IL-12 and induce T-bet, even in the absence of antigen. TE cell formation following 2o or 3o infections was dependent on increased T-bet expression because T-bet+/− cells were resistant to these phenotypic changes. Larger numbers of pre-existing memory CD8 T cells limited the duration of 2o infection and the amount of IL-12 produced, and consequently, this reduced T-bet expression and the proportion of 2o TE CD8 T cells that formed. Together, these data show that, over repeated infections, memory CD8 T cell quality and proliferative fitness is not strictly determined by the number of serial encounters with antigen or cell divisions, but is a function of the CD8 T cell differentiation state, which is genetically controlled in a T-bet-dependent manner. This differentiation state can be modulated by pre-existing memory CD8 T cell number and the intensity of inflammation during reinfection. These results have important implications for vaccinations involving prime-boost strategies. PMID:21930973

  20. Mesenchymal stromal cells engage complement and complement receptor bearing innate effector cells to modulate immune responses.

    Directory of Open Access Journals (Sweden)

    Guido Moll

    Full Text Available Infusion of human third-party mesenchymal stromal cells (MSCs appears to be a promising therapy for acute graft-versus-host disease (aGvHD. To date, little is known about how MSCs interact with the body's innate immune system after clinical infusion. This study shows, that exposure of MSCs to blood type ABO-matched human blood activates the complement system, which triggers complement-mediated lymphoid and myeloid effector cell activation in blood. We found deposition of complement component C3-derived fragments iC3b and C3dg on MSCs and fluid-phase generation of the chemotactic anaphylatoxins C3a and C5a. MSCs bound low amounts of immunoglobulins and lacked expression of complement regulatory proteins MCP (CD46 and DAF (CD55, but were protected from complement lysis via expression of protectin (CD59. Cell-surface-opsonization and anaphylatoxin-formation triggered complement receptor 3 (CD11b/CD18-mediated effector cell activation in blood. The complement-activating properties of individual MSCs were furthermore correlated with their potency to inhibit PBMC-proliferation in vitro, and both effector cell activation and the immunosuppressive effect could be blocked either by using complement inhibitor Compstatin or by depletion of CD14/CD11b-high myeloid effector cells from mixed lymphocyte reactions. Our study demonstrates for the first time a major role of the complement system in governing the immunomodulatory activity of MSCs and elucidates how complement activation mediates the interaction with other immune cells.

  1. Separate developmental programs for HLA-A and -B cell surface expression during differentiation from embryonic stem cells to lymphocytes, adipocytes and osteoblasts.

    Directory of Open Access Journals (Sweden)

    Hardee J Sabir

    Full Text Available A major problem of allogeneic stem cell therapy is immunologically mediated graft rejection. HLA class I A, B, and Cw antigens are crucial factors, but little is known of their respective expression on stem cells and their progenies. We have recently shown that locus-specific expression (HLA-A, but not -B is seen on some multipotent stem cells, and this raises the question how this is in other stem cells and how it changes during differentiation. In this study, we have used flow cytometry to investigate the cell surface expression of HLA-A and -B on human embryonic stem cells (hESC, human hematopoietic stem cells (hHSC, human mesenchymal stem cells (hMSC and their fully-differentiated progenies such as lymphocytes, adipocytes and osteoblasts. hESC showed extremely low levels of HLA-A and no -B. In contrast, multipotent hMSC and hHSC generally expressed higher levels of HLA-A and clearly HLA-B though at lower levels. IFNγ induced HLA-A to very high levels on both hESC and hMSC and HLA-B on hMSC. Even on hESC, a low expression of HLA-B was achieved. Differentiation of hMSC to osteoblasts downregulated HLA-A expression (P = 0.017. Interestingly HLA class I on T lymphocytes differed between different compartments. Mature bone marrow CD4(+ and CD8(+ T cells expressed similar HLA-A and -B levels as hHSC, while in the peripheral blood they expressed significantly more HLA-B7 (P = 0.0007 and P = 0.004 for CD4(+ and CD8(+ T cells, respectively. Thus different HLA loci are differentially regulated during differentiation of stem cells.

  2. Corrected Lymphocyte Percentages Reduce the Differences in Absolute CD4+ T Lymphocyte Counts between Dual-Platform and Single-Platform Flow Cytometric Approaches.

    Science.gov (United States)

    Noulsri, Egarit; Abudaya, Dinar; Lerdwana, Surada; Pattanapanyasat, Kovit

    2018-03-13

    To determine whether a corrected lymphocyte percentage could reduce bias in the absolute cluster of differentiation (CD)4+ T lymphocyte counts obtained via dual-platform (DP) vs standard single-platform (SP) flow cytometry. The correction factor (CF) for the lymphocyte percentages was calculated at 6 laboratories. The absolute CD4+ T lymphocyte counts in 300 blood specimens infected with human immunodeficiency virus (HIV) were determined using the DP and SP methods. Applying the CFs revealed that 4 sites showed a decrease in the mean bias of absolute CD4+ T lymphocyte counts determined via DP vs standard SP (-109 vs -84 cells/μL, -80 vs -58 cells/μL, -52 vs -45 cells/μL, and -32 vs 1 cells/μL). However, 2 participating laboratories revealed an increase in the difference of the mean bias (-42 vs -49 cells/μL and -20 vs -69 cells/μL). Use of the corrected lymphocyte percentage shows potential for decreasing the difference in CD4 counts between DP and the standard SP method.

  3. GTP- and GDP-Dependent Rab27a Effectors in Pancreatic Beta-Cells.

    Science.gov (United States)

    Yamaoka, Mami; Ishizaki, Toshimasa; Kimura, Toshihide

    2015-01-01

    Small guanosine triphosphatases (GTPases) participate in a wide variety of cellular functions including proliferation, differentiation, adhesion, and intracellular transport. Conventionally, only the guanosine 5'-triphosphate (GTP)-bound small GTPase interacts with effector proteins, and the resulting downstream signals control specific cellular functions. Therefore, the GTP-bound form is regarded as active, and the focus has been on searching for proteins that bind the GTP form to look for their effectors. The Rab family small GTPase Rab27a is highly expressed in some secretory cells and is involved in the control of membrane traffic. The present study reviews recent progress in our understanding of the roles of Rab27a and its effectors in pancreatic beta-cells. In the basal state, GTP-bound Rab27a controls insulin secretion at pre-exocytic stages via its GTP-dependent effectors. We previously identified novel guanosine 5'-diphosphate (GDP)-bound Rab27-interacting proteins. Interestingly, GDP-bound Rab27a controls endocytosis of the secretory membrane via its interaction with these proteins. We also demonstrated that the insulin secretagogue glucose converts Rab27a from its GTP- to GDP-bound forms. Thus, GTP- and GDP-bound Rab27a regulate pre-exocytic and endocytic stages in membrane traffic, respectively. Since the physiological importance of GDP-bound GTPases has been largely overlooked, we consider that the investigation of GDP-dependent effectors for other GTPases is necessary for further understanding of cellular function.

  4. Genetic engineering of chimeric antigen receptors using lamprey derived variable lymphocyte receptors

    Directory of Open Access Journals (Sweden)

    Robert Moot

    2016-01-01

    Full Text Available Chimeric antigen receptors (CARs are used to redirect effector cell specificity to selected cell surface antigens. Using CARs, antitumor activity can be initiated in patients with no prior tumor specific immunity. Although CARs have shown promising clinical results, the technology remains limited by the availability of specific cognate cell target antigens. To increase the repertoire of targetable tumor cell antigens we utilized the immune system of the sea lamprey to generate directed variable lymphocyte receptors (VLRs. VLRs serve as membrane bound and soluble immune effectors analogous but not homologous to immunoglobulins. They have a fundamentally different structure than immunoglobulin (Ig-based antibodies while still demonstrating high degrees of specificity and affinity. To test the functionality of VLRs as the antigen recognition domain of CARs, two VLR-CARs were created. One contained a VLR specific for a murine B cell leukemia and the other contained a VLR specific for the human T cell surface antigen, CD5. The CAR design consisted of the VLR sequence, myc-epitope tag, CD28 transmembrane domain, and intracellular CD3ζ signaling domain. We demonstrate proof of concept, including gene transfer, biosynthesis, cell surface localization, and effector cell activation for multiple VLR-CAR designs. Therefore, VLRs provide an alternative means of CAR-based cancer recognition.

  5. Segregation of B lymphocytes into stationary apoptotic and migratory proliferating subpopulations in agglomerate cultures with ileal epithelium.

    Science.gov (United States)

    Alitheen, N; McClure, S; McCullagh, P

    2001-09-01

    The B lymphocyte-epithelial cell interactions that define the microenvironment of the ileal Peyer's patch, the primary B lymphocyte organ of the fetal lamb, have been replicated in tissue culture. Mixed suspensions of ileal epithelial cells, lymphocytes and fibroblasts from fetuses of 63-103 days of gestation organized into macroscopically visible agglomerates within 72 h. These agglomerates contained translucent spherical cavities and were enclosed within a marginal cell layer and surrounded by an expanding corona of emigrating cells. The lining of the cavities and the marginal layer consisted of well-differentiated, polarized columnar ileal epithelial cells. One population of B lymphocytes in the initial mixed suspension differentiated into two discrete populations reproducing the characteristics of intact fetal ileal Peyer's patches. B cells apposed to follicle-associated epithelium (FAE) within agglomerates underwent apoptosis. The other population of emigrant B cells proliferated and expressed the BAQ44A differentiation marker. Differentiation of ileal epithelial cells into FAE, typical of Peyer's patches, was markedly accelerated. The mutually inductive influences of intestinal epithelial cells and B lymphocytes in these agglomerates replicate normal mid-gestational fetal development of the mucosal immune system and afford new opportunities for its further investigation.

  6. miRNA profiling of naive, effector and memory CD8 T cells.

    Directory of Open Access Journals (Sweden)

    Haoquan Wu

    Full Text Available microRNAs have recently emerged as master regulators of gene expression during development and cell differentiation. Although profound changes in gene expression also occur during antigen-induced T cell differentiation, the role of miRNAs in the process is not known. We compared the miRNA expression profiles between antigen-specific naïve, effector and memory CD8+ T cells using 3 different methods--small RNA cloning, miRNA microarray analysis and real-time PCR. Although many miRNAs were expressed in all the T cell subsets, the frequency of 7 miRNAs (miR-16, miR-21, miR-142-3p, miR-142-5p, miR-150, miR-15b and let-7f alone accounted for approximately 60% of all miRNAs, and their expression was several fold higher than the other expressed miRNAs. Global downregulation of miRNAs (including 6/7 dominantly expressed miRNAs was observed in effector T cells compared to naïve cells and the miRNA expression levels tended to come back up in memory T cells. However, a few miRNAs, notably miR-21 were higher in effector and memory T cells compared to naïve T cells. These results suggest that concomitant with profound changes in gene expression, miRNA profile also changes dynamically during T cell differentiation. Sequence analysis of the cloned mature miRNAs revealed an extensive degree of end polymorphism. While 3'end polymorphisms dominated, heterogeneity at both ends, resembling drosha/dicer processing shift was also seen in miR-142, suggesting a possible novel mechanism to generate new miRNA and/or to diversify miRNA target selection. Overall, our results suggest that dynamic changes in the expression of miRNAs may be important for the regulation of gene expression during antigen-induced T cell differentiation. Our study also suggests possible novel mechanisms for miRNA biogenesis and function.

  7. Structure and evolution of barley powdery mildew effector candidates

    Directory of Open Access Journals (Sweden)

    Pedersen Carsten

    2012-12-01

    Full Text Available Abstract Background Protein effectors of pathogenicity are instrumental in modulating host immunity and disease resistance. The powdery mildew pathogen of grasses Blumeria graminis causes one of the most important diseases of cereal crops. B. graminis is an obligate biotrophic pathogen and as such has an absolute requirement to suppress or avoid host immunity if it is to survive and cause disease. Results Here we characterise a superfamily predicted to be the full complement of Candidates for Secreted Effector Proteins (CSEPs in the fungal barley powdery mildew parasite B. graminis f.sp. hordei. The 491 genes encoding these proteins constitute over 7% of this pathogen’s annotated genes and most were grouped into 72 families of up to 59 members. They were predominantly expressed in the intracellular feeding structures called haustoria, and proteins specifically associated with the haustoria were identified by large-scale mass spectrometry-based proteomics. There are two major types of effector families: one comprises shorter proteins (100–150 amino acids, with a high relative expression level in the haustoria and evidence of extensive diversifying selection between paralogs; the second type consists of longer proteins (300–400 amino acids, with lower levels of differential expression and evidence of purifying selection between paralogs. An analysis of the predicted protein structures underscores their overall similarity to known fungal effectors, but also highlights unexpected structural affinities to ribonucleases throughout the entire effector super-family. Candidate effector genes belonging to the same family are loosely clustered in the genome and are associated with repetitive DNA derived from retro-transposons. Conclusions We employed the full complement of genomic, transcriptomic and proteomic analyses as well as structural prediction methods to identify and characterize the members of the CSEPs superfamily in B. graminis f

  8. Generation mechanism of RANKL(+) effector memory B cells: relevance to the pathogenesis of rheumatoid arthritis.

    Science.gov (United States)

    Ota, Yuri; Niiro, Hiroaki; Ota, Shun-Ichiro; Ueki, Naoko; Tsuzuki, Hirofumi; Nakayama, Tsuyoshi; Mishima, Koji; Higashioka, Kazuhiko; Jabbarzadeh-Tabrizi, Siamak; Mitoma, Hiroki; Akahoshi, Mitsuteru; Arinobu, Yojiro; Kukita, Akiko; Yamada, Hisakata; Tsukamoto, Hiroshi; Akashi, Koichi

    2016-03-16

    The efficacy of B cell-depleting therapies for rheumatoid arthritis underscores antibody-independent functions of effector B cells such as cognate T-B interactions and production of pro-inflammatory cytokines. Receptor activator of nuclear factor κB ligand (RANKL) is a key cytokine involved in bone destruction and is highly expressed in synovial fluid B cells in patients with rheumatoid arthritis. In this study we sought to clarify the generation mechanism of RANKL(+) effector B cells and their impacts on osteoclast differentiation. Peripheral blood and synovial fluid B cells from healthy controls and patients with rheumatoid arthritis were isolated using cell sorter. mRNA expression of RANKL, osteoprotegerin, tumor necrosis factor (TNF)-α, and Blimp-1 was analyzed by quantitative real-time polymerase chain reaction. Levels of RANKL, CD80, CD86, and CXCR3 were analyzed using flow cytometry. Functional analysis of osteoclastogenesis was carried out in the co-culture system using macrophage RAW264 reporter cells. RANKL expression was accentuated in CD80(+)CD86(+) B cells, a highly activated B-cell subset more abundantly observed in patients with rheumatoid arthritis. Upon activation via B-cell receptor and CD40, switched-memory B cells predominantly expressed RANKL, which was further augmented by interferon-γ (IFN-γ) but suppressed by interleukin-21. Strikingly, IFN-γ also enhanced TNF-α expression, while it strongly suppressed osteoprotegerin expression in B cells. IFN-γ increased the generation of CXCR3(+)RANKL(+) effector B cells, mimicking the synovial B cell phenotype in patients with rheumatoid arthritis. Finally, RANKL(+) effector B cells in concert with TNF-α facilitated osteoclast differentiation in vitro. Our current findings have shed light on the generation mechanism of pathogenic RANKL(+) effector B cells that would be an ideal therapeutic target for rheumatoid arthritis in the future.

  9. Altered effector function of peripheral cytotoxic cells in COPD

    Directory of Open Access Journals (Sweden)

    Corne Jonathan M

    2009-06-01

    Full Text Available Abstract Background There is mounting evidence that perforin and granzymes are important mediators in the lung destruction seen in COPD. We investigated the characteristics of the three main perforin and granzyme containing peripheral cells, namely CD8+ T lymphocytes, natural killer (NK; CD56+CD3- cells and NKT-like (CD56+CD3+ cells. Methods Peripheral blood mononuclear cells (PBMCs were isolated and cell numbers and intracellular granzyme B and perforin were analysed by flow cytometry. Immunomagnetically selected CD8+ T lymphocytes, NK (CD56+CD3- and NKT-like (CD56+CD3+ cells were used in an LDH release assay to determine cytotoxicity and cytotoxic mechanisms were investigated by blocking perforin and granzyme B with relevant antibodies. Results The proportion of peripheral blood NKT-like (CD56+CD3+ cells in smokers with COPD (COPD subjects was significantly lower (0.6% than in healthy smokers (smokers (2.8%, p +CD3- cells from COPD subjects were significantly less cytotoxic than in smokers (16.8% vs 51.9% specific lysis, p +CD3+ cells (16.7% vs 52.4% specific lysis, p +CD3- and NKT-like (CD56+CD3+ cells from smokers and HNS. Conclusion In this study, we show that the relative numbers of peripheral blood NK (CD56+CD3- and NKT-like (CD56+CD3+ cells in COPD subjects are reduced and that their cytotoxic effector function is defective.

  10. The timing of T cell priming and cycling

    Directory of Open Access Journals (Sweden)

    Reinhard eObst

    2015-11-01

    Full Text Available The proliferation of specific lymphocytes is the central tenet of the clonal selection paradigm. Antigen recognition by T cells triggers a series of events that produces expanded clones of differentiated effector cells. TCR signaling events are detectable within seconds and minutes and are likely to continue for hours and days in vivo. Here, I review the work done on the importance of TCR signals in the later part of the expansion phase of the primary T cell response, primarily regarding the regulation of the cell cycle in CD4+ and CD8+ cells. The results suggest a degree of programming by early signals for effector differentiation, particularly in the CD8+ T cell compartment, with optimal expansion supported by persistent antigen presentation later on. Differences to CD4+ T cell expansion and new avenues towards a molecular understanding of cell cycle regulation in lymphocytes are discussed.

  11. Suppression of cytotoxic T lymphocytes by carrageenan-activated macrophage-like cells

    International Nuclear Information System (INIS)

    Yung, Y.P.; Cudkowicz, G.

    1978-01-01

    In the presence of 100 μg/ml of carrageenans (CAR), B6D2F 1 responder spleen cells failed to generate antiparent or anti-allogeneic cytotoxic T lymphocytes in vitro, but instead generated suppressor cells. Cultured CAR-treated cells added to mixtures of B6D2F 1 anti-B6 or B6D2F 1 anti-C3H cytotoxic effectors (induced in vitro) and the appropriate 51 Cr-labeled lymphoma targets reduced or abolished cytolysis (measured as 51 Cr release) depending on the ratio of suppressor to effector cells. Cultured spleen cells not exposed to CAR failed to inhibit both types of cytotoxicity. Presuppressor cells were associated with a splenic subpopulation independent of the thymus (i.e., present in spleens of athymic nude mice), were moderately adherent to Sephadex G-10 columns, but were not phagocytic or ''sticky'' to carbonyl iron particles. Activation of such cells by CAR was not prevented by in vitro exposure to 2000 rads of γ-rays before culture, nor facilitated by antigenic stimulation. The matured suppressor cells remained radioresistant and became strongly adherent to Sephadex G-10. The suppressors lacked surface Thy-1 alloantigen detectable by antibody and rabbit complement. Suppressor cell activity was not restricted by the immunologic specificity and major histocompatibility type of effectors

  12. The role of lymphocytes in radiotherapy-induced adverse late effects in the lung

    Directory of Open Access Journals (Sweden)

    Florian Wirsdörfer

    2016-12-01

    Full Text Available Radiation-induced pneumonitis and fibrosis are dose-limiting side effects of thoracic irradiation. Thoracic irradiation triggers acute and chronic environmental lung changes that are shaped by the damage response of resident cells, by the resulting reaction of the immune system, and by repair processes. Although considerable progress has been made during the last decade in defining involved effector cells and soluble mediators, the network of pathophysiological events and the cellular cross-talk linking acute tissue damage to chronic inflammation and fibrosis still require further definition. Infiltration of cells from the innate and adaptive immune systems is a common response of normal tissues to ionizing radiation. Herein lymphocytes represent a versatile and wide-ranged group of cells of the adaptive immune system that can react under specific conditions in various ways and participate in modulating the lung environment by adopting pro-inflammatory, anti-inflammatory or even pro- or anti-fibrotic phenotypes. The present review provides an overview on published data about the role of lymphocytes in radiation-induced lung disease and related damage-associated pulmonary diseases with a focus on T-lymphocytes and B-lymphocytes. We also discuss the suspected dual role of specific lymphocyte subsets during the pneumonitic phase and fibrotic phase that is shaped by the environmental conditions and the interaction and the intercellular cross-talk between cells from the innate and adaptive immune systems and (damaged resident epithelial cells and stromal cells (e.g. endothelial cells, mesenchymal stem cells (MSC, fibroblasts. Finally, we highlight potential therapeutic targets suited to counteract pathological lymphocyte responses to prevent or treat radiation-induced lung disease.

  13. Sensitivity of T-Lymphocytes to Hormones of the Anterior Pituitary Gland.

    Science.gov (United States)

    Tishevskaya, N V; Gevorkyan, N M; Kozlova, N I

    2017-01-01

    The review provides information about the features of the sensitivity of thymocytes, lymphoid organs' cells and T-lymphocytes of peripheral blood to the hormones secreted by anterior pituitary gland's cells: growth hormone, thyrotropin, adrenocorticotropic hormone, prolactin and β-endorphin. Some aspects of the T-lymphocytes's response to humoral signals from the hypophysis are shown in the article. Also the pituitary hormones' role in the regulation of proliferation, differentiation, and cytokine production of T-lymphocytes in normal and pathological conditions of the organism being discussed.

  14. Repeat-containing protein effectors of plant-associated organisms

    Directory of Open Access Journals (Sweden)

    Carl H. Mesarich

    2015-10-01

    Full Text Available Many plant-associated organisms, including microbes, nematodes, and insects, deliver effector proteins into the apoplast, vascular tissue, or cell cytoplasm of their prospective hosts. These effectors function to promote colonization, typically by altering host physiology or by modulating host immune responses. The same effectors however, can also trigger host immunity in the presence of cognate host immune receptor proteins, and thus prevent colonization. To circumvent effector-triggered immunity, or to further enhance host colonization, plant-associated organisms often rely on adaptive effector evolution. In recent years, it has become increasingly apparent that several effectors of plant-associated organisms are repeat-containing proteins (RCPs that carry tandem or non-tandem arrays of an amino acid sequence or structural motif. In this review, we highlight the diverse roles that these repeat domains play in RCP effector function. We also draw attention to the potential role of these repeat domains in adaptive evolution with regards to RCP effector function and the evasion of effector-triggered immunity. The aim of this review is to increase the profile of RCP effectors from plant-associated organisms.

  15. Epigenetic landscapes reveal transcription factors regulating CD8+ T cell differentiation

    Science.gov (United States)

    Yu, Bingfei; Zhang, Kai; Milner, J. Justin; Toma, Clara; Chen, Runqiang; Scott-Browne, James P.; Pereira, Renata M.; Crotty, Shane; Chang, John T.; Pipkin, Matthew E.; Wang, Wei; Goldrath, Ananda W.

    2017-01-01

    Dynamic changes in the expression of transcription factors (TFs) can influence specification of distinct CD8+ T cell fates, but the observation of equivalent expression of TF among differentially-fated precursor cells suggests additional underlying mechanisms. Here, we profiled genome-wide histone modifications, open chromatin and gene expression of naive, terminal-effector, memory-precursor and memory CD8+ T cell populations induced during the in vivo response to bacterial infection. Integration of these data suggested that TF expression and binding contributed to establishment of subset-specific enhancers during differentiation. We developed a new bioinformatics method using the PageRank algorithm to reveal novel TFs influencing the generation of effector and memory populations. The TFs YY1 and Nr3c1, both constitutively expressed during CD8+ T cell differentiation, regulated the formation of terminal-effector and memory-precursor cell-fates, respectively. Our data define the epigenetic landscape of differentiation intermediates, facilitating identification of TFs with previously unappreciated roles in CD8+ T cell differentiation. PMID:28288100

  16. Tumor infiltrating lymphocytes: an intriguing player in the survival of colorectal cancer patients

    Directory of Open Access Journals (Sweden)

    Lardon Filip

    2010-04-01

    Full Text Available Abstract Background There is growing evidence that both local and systemic inflammatory responses play an important role in the progression of a variety of solid tumors. Colorectal cancer results from the cumulative effect of sequential genetic alterations, leading to the expression of tumor associated antigens possibly inducing a cellular anti-tumor immune response. It is well recognized that cytotoxic lymphocytes constitute one of the most important effector mechanisms of anti-tumor-immunity. However, their potential prognostic influence in colorectal cancer remains controversial. Aim of the study was to examine infiltration of CD3+ and CD8+ lymphocytes in colorectal cancer and their prognostic potential. Two-hundred-fifteen colorectal cancer cases, previously analyzed for microsatellite instability (MSI, were selected for immunohistochemical detection of CD3+, CD8+ infiltration and the expression of granzyme B. Prognostic relevance was assessed by survival analysis. Results Strong correlations were found between the infiltration of lymphocytes and several clinicopathological variables. Survival analysis revealed that intra-epithelial infiltration of CD3+ and CD8+ T lymphocytes and stromal infiltration of CD3+ lymphocytes had a major impact on the patients' overall survival in the univariate analysis, however independent of their association with MSI-status. In addition, it was also demonstrated that there was an important disease specific survival advantage for patients with microsatellite stable (MSS tumors containing intraepithelial CD8+ tumor infiltrating lymphocytes. When samples were analyzed for colon cancer and rectal cancer separately, the results of the overall population were confirmed in colon cancer only. When entered into a multiple Cox regression analysis adjusting for other possible important confounding factors, the strong impact of lymphocyte infiltration on overall survival was not maintained. Only early stage and young age

  17. Clonal expansion of CD4(+) cytotoxic T lymphocytes in patients with IgG4-related disease.

    Science.gov (United States)

    Mattoo, Hamid; Mahajan, Vinay S; Maehara, Takashi; Deshpande, Vikram; Della-Torre, Emanuel; Wallace, Zachary S; Kulikova, Maria; Drijvers, Jefte M; Daccache, Joe; Carruthers, Mollie N; Castelino, Flavia V; Stone, James R; Stone, John H; Pillai, Shiv

    2016-09-01

    IgG4-related disease (IgG4-RD) is a systemic condition of unknown cause characterized by highly fibrotic lesions with dense lymphoplasmacytic infiltrates. CD4(+) T cells constitute the major inflammatory cell population in IgG4-RD lesions. We used an unbiased approach to characterize CD4(+) T-cell subsets in patients with IgG4-RD based on their clonal expansion and ability to infiltrate affected tissue sites. We used flow cytometry to identify CD4(+) effector/memory T cells in a cohort of 101 patients with IgG4-RD. These expanded cells were characterized by means of gene expression analysis and flow cytometry. Next-generation sequencing of the T-cell receptor β chain gene was performed on CD4(+)SLAMF7(+) cytotoxic T lymphocytes (CTLs) and CD4(+)GATA3(+) TH2 cells in a subset of patients to identify their clonality. Tissue infiltration by specific T cells was examined by using quantitative multicolor imaging. CD4(+) effector/memory T cells with a cytolytic phenotype were expanded in patients with IgG4-RD. Next-generation sequencing revealed prominent clonal expansions of these CD4(+) CTLs but not CD4(+)GATA3(+) memory TH2 cells in patients with IgG4-RD. The dominant T cells infiltrating a range of inflamed IgG4-RD tissue sites were clonally expanded CD4(+) CTLs that expressed SLAMF7, granzyme A, IL-1β, and TGF-β1. Clinical remission induced by rituximab-mediated B-cell depletion was associated with a reduction in numbers of disease-associated CD4(+) CTLs. IgG4-RD is prominently linked to clonally expanded IL-1β- and TGF-β1-secreting CD4(+) CTLs in both peripheral blood and inflammatory tissue lesions. These active, terminally differentiated, cytokine-secreting effector CD4(+) T cells are now linked to a human disease characterized by chronic inflammation and fibrosis. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  18. Graft rejection by cytolytic T cells. Specificity of the effector mechanism in the rejection of allogeneic marrow

    International Nuclear Information System (INIS)

    Nakamura, H.; Gress, R.E.

    1990-01-01

    Cellular effector mechanisms of allograft rejection remain incompletely described. Characterizing the rejection of foreign-marrow allografts rather than solid-organ grafts has the advantage that the cellular composition of the marrow graft, as a single cell suspension, can be altered to include cellular components with differing antigen expression. Rejection of marrow grafts is sensitive to lethal doses of radiation in the mouse but resistant to sublethal levels of radiation. In an effort to identify cells mediating host resistance, lymphocytes were isolated and cloned from spleens of mice 7 days after sublethal TBI (650 cGy) and inoculation with allogeneic marrow. All clones isolated were cytolytic with specificity for MHC encoded gene products of the allogeneic marrow donor. When cloned cells were transferred in vivo into lethally irradiated (1025 cGy) recipients unable to reject allogeneic marrow, results utilizing splenic 125IUdR uptake indicated that these MHC-specific cytotoxic clones could suppress marrow proliferation. In order to characterize the effector mechanism and the ability of the clones to affect final engraftment, double donor chimeras were constructed so that 2 target cell populations differing at the MHC from each other and from the host were present in the same marrow allograft. Results directly demonstrated an ability of CTL of host MHC type to mediate graft rejection and characterized the effector mechanism as one with specificity for MHC gene products

  19. Chimeric PD-1:28 Receptor Upgrades Low-Avidity T cells and Restores Effector Function of Tumor-Infiltrating Lymphocytes for Adoptive Cell Therapy.

    Science.gov (United States)

    Schlenker, Ramona; Olguín-Contreras, Luis Felipe; Leisegang, Matthias; Schnappinger, Julia; Disovic, Anja; Rühland, Svenja; Nelson, Peter J; Leonhardt, Heinrich; Harz, Hartmann; Wilde, Susanne; Schendel, Dolores J; Uckert, Wolfgang; Willimsky, Gerald; Noessner, Elfriede

    2017-07-01

    Inherent intermediate- to low-affinity T-cell receptors (TCR) that develop during the natural course of immune responses may not allow sufficient activation for tumor elimination, making the majority of T cells suboptimal for adoptive T-cell therapy (ATT). TCR affinity enhancement has been implemented to provide stronger T-cell activity but carries the risk of creating undesired cross-reactivity leading to potential serious adverse effects in clinical application. We demonstrate here that engineering of low-avidity T cells recognizing a naturally processed and presented tumor-associated antigen with a chimeric PD-1:28 receptor increases effector function to levels seen with high-avidity T cells of identical specificity. Upgrading the function of low-avidity T cells without changing the TCR affinity will allow a large arsenal of low-avidity T cells previously thought to be therapeutically inefficient to be considered for ATT. PD-1:28 engineering reinstated Th1 function in tumor-infiltrating lymphocytes that had been functionally disabled in the human renal cell carcinoma environment without unleashing undesired Th2 cytokines or IL10. Involved mechanisms may be correlated to restoration of ERK and AKT signaling pathways. In mouse tumor models of ATT, PD-1:28 engineering enabled low-avidity T cells to proliferate stronger and prevented PD-L1 upregulation and Th2 polarization in the tumor milieu. Engineered T cells combined with checkpoint blockade secreted significantly more IFNγ compared with T cells without PD-1:28, suggesting a beneficial combination with checkpoint blockade therapy or other therapeutic strategies. Altogether, the supportive effects of PD-1:28 engineering on T-cell function make it an attractive tool for ATT. Cancer Res; 77(13); 3577-90. ©2017 AACR . ©2017 American Association for Cancer Research.

  20. Differential immunotoxic effects of ethanol on murine EL-4 lymphoma and normal lymphocytes is mediated through increased ROS production and activation of p38MAPK.

    Science.gov (United States)

    Premachandran, Sudha; Khan, Nazir M; Thakur, Vikas S; Shukla, Jyoti; Poduval, T B

    2012-08-01

    Ethanol has been used to achieve thymic depletion in myasthenia gravis patients. Ethanol (95%) has also been used widely in the therapy of many tumors including hepatocellular carcinoma. In light of these findings, we delineated the differential immunotoxic behavior and mechanism of lower concentration of ethanol towards murine EL-4 lymphoma and its normal counterpart lymphocytes. EL-4 lymphoma and normal lymphocytes were cultured with ethanol (0%-5%) for 6 h and cytotoxicity was measured by various methods. EL-4 cells treated with ethanol showed concentration-dependent loss of viability at 2%-5% ethanol concentration and exhibit proliferative arrest at preG1 stage. Acridine-orange and ethidium-bromide staining indicated that ethanol induced death in EL-4 cells, by induction of both apoptosis and necrosis which was further supported by findings of DNA-fragmentation and trypan blue dye exclusion test. However, treatment of lymphocytes with similar concentration of ethanol did not show any death-associated parameters. Furthermore, ethanol induced significantly higher ROS generation in EL-4 cells as compared to lymphocytes and caused PARP cleavage and activation of apoptotic proteins like p53 and Bax, in EL-4 cells and not in normal lymphocytes. In addition, ethanol exposure to EL-4 cells led to phosphorylation of p38MAPK, and upregulation of death receptor Fas (CD95). Taken together, these results suggest that ethanol upto a concentration of 5% caused no significant immunotoxicity towards normal lymphocytes and induced cell death in EL-4 cells via phosphorylation of p38MAPK and regulation of p53 leading to further activation of both extrinsic (Fas) and intrinsic (Bax) apoptotic markers.

  1. Preventing Allograft Rejection by Targeting Immune Metabolism

    Directory of Open Access Journals (Sweden)

    Chen-Fang Lee

    2015-10-01

    Full Text Available Upon antigen recognition and co-stimulation, T lymphocytes upregulate the metabolic machinery necessary to proliferate and sustain effector function. This metabolic reprogramming in T cells regulates T cell activation and differentiation but is not just a consequence of antigen recognition. Although such metabolic reprogramming promotes the differentiation and function of T effector cells, the differentiation of regulatory T cells employs different metabolic reprogramming. Therefore, we hypothesized that inhibition of glycolysis and glutamine metabolism might prevent graft rejection by inhibiting effector generation and function and promoting regulatory T cell generation. We devised an anti-rejection regimen involving the glycolytic inhibitor 2-deoxyglucose (2-DG, the anti-type II diabetes drug metformin, and the inhibitor of glutamine metabolism 6-diazo-5-oxo-L-norleucine (DON. Using this triple-drug regimen, we were able to prevent or delay graft rejection in fully mismatched skin and heart allograft transplantation models.

  2. Failure of lymphocyte-membrane HLA-A and -B expression in two siblings with combined immunodeficiency

    NARCIS (Netherlands)

    Schuurman, R.K.B.; Rood, J.J. van; Vossen, J.M.; Schellekens, P.Th.A.; Feltkamp-Vroom, Th.M.; Doyer, E.; Gmelig Meyling, F.H.J.; Visser, H.K.A.

    1979-01-01

    A diagnosis of partial combined immunodeficiency was made in two Turkish siblings with a history of multiple pyogenic infections and persistent candidiasis. They demonstrated severe hypo-γ-globulinemia, with B-lymphocytes, but deficient plasma cell differentiation. T-Lymphocytes were decreased in

  3. Co-Culturing of Multipotent Mesenchymal Stromal Cells with Autological and Allogenic Lymphocytes.

    Science.gov (United States)

    Kapranov, N M; Davydova, Yu O; Gal'tseva, I V; Petinati, N A; Bakshinskaitė, M V; Drize, N I; Kuz'mina, L A; Parovichnikova, E N; Savchenko, V G

    2018-03-01

    We studied the effect of autologous and allogeneic lymphocytes on multipotent mesenchymal stromal cells in co-culture. It is shown that changes in multipotent mesenchymal stromal cells and in lymphocytes did not depend on the source of lymphocytes. Contact with lymphocytes triggers expression of HLA-DR molecules on multipotent mesenchymal stromal cells and these cells lose their immune privilege. In multipotent mesenchymal stromal cells, the relative level of expression of factors involved in immunomodulation (IDO1, PTGES, and IL-6) and expression of adhesion molecule ICAM1 increased, while expression of genes involved in the differentiation of multipotent mesenchymal stromal cells remained unchanged. Priming of multipotent mesenchymal stromal cells with IFN did not affect these changes. In turn, lymphocytes underwent activation, expression of HLA-DR increased, subpopulation composition of lymphocytes changed towards the increase in the content of naïve T cells. These findings are important for cell therapy.

  4. T-lymphocyte dependency of B-lymphocyte blastogenic response to phytomitogens

    International Nuclear Information System (INIS)

    Han, T.; Dadey, B.

    1978-01-01

    Human peripheral blood T and B lymphocytes were separated by a method based on the stable rosette formation of T lymphocytes with neuraminidase-treated sheep erythrocytes, followed by centrifugation over a Ficoll-Hypaque gradient. Monocytes were isolated from the T-depleted B lymphocyte preparation by allowing the monocytes to ingest iron particles and by subsequent centrifugation over a Ficoll-Hypaque gradient. The T lymphocytes responded extremely well to PHA and very well to PWM, while the B lymphocytes were unresponsive to either PHA or PWM. However, when the B lymphocytes were cultured together with irradiated autologous or allogeneic T lymphocytes (1 : 1,1:2 or 1 : 4 ratio), both PHA and PWM became mitogenic to B lymphocytes. Irradiated T lymphocytes alone did not respond to either PHA or PWM, indicating that the 3 H-thymidine incorporation seen in the mixed-cell culture was due to the activation of unirradiated B lymphocytes. The B lymphocytes failed to respond to these phytomitogens in the presence of lower concentrations of irradiated T lymphocytes. The monocytes were found to be incapable of helping the B lymphocytes to respond to PHA or PWM. (author)

  5. Structure of the effector-binding domain of the arabinose repressor AraR from Bacillus subtilis

    Energy Technology Data Exchange (ETDEWEB)

    Procházková, Kateřina; Čermáková, Kateřina [Academy of Sciences of the Czech Republic, Flemingovo nam. 2, Prague 6 (Czech Republic); Pachl, Petr; Sieglová, Irena [Academy of Sciences of the Czech Republic, Flemingovo nam. 2, Prague 6 (Czech Republic); Academy of Sciences of the Czech Republic, Videnska 1083, Prague 4 (Czech Republic); Fábry, Milan [Academy of Sciences of the Czech Republic, Videnska 1083, Prague 4 (Czech Republic); Otwinowski, Zbyszek [UT Southwestern Medical Center, Dallas, Texas (United States); Řezáčová, Pavlína, E-mail: rezacova@uochb.cas.cz [Academy of Sciences of the Czech Republic, Flemingovo nam. 2, Prague 6 (Czech Republic); Academy of Sciences of the Czech Republic, Videnska 1083, Prague 4 (Czech Republic)

    2012-02-01

    The crystal structure of the effector-binding domain of the transcriptional repressor AraR from B. subtilis in complex with the effector molecule (l-arabinose) was determined at 2.2 Å resolution. A detailed analysis of the crystal identified a dimer organization that is distinctive from that of other members of the GalR/LacI family. In Bacillus subtilis, the arabinose repressor AraR negatively controls the expression of genes in the metabolic pathway of arabinose-containing polysaccharides. The protein is composed of two domains of different phylogenetic origin and function: an N-terminal DNA-binding domain belonging to the GntR family and a C-terminal effector-binding domain that shows similarity to members of the GalR/LacI family. The crystal structure of the C-terminal effector-binding domain of AraR in complex with the effector l-arabinose has been determined at 2.2 Å resolution. The l-arabinose binding affinity was characterized by isothermal titration calorimetry and differential scanning fluorimetry; the K{sub d} value was 8.4 ± 0.4 µM. The effect of l-arabinose on the protein oligomeric state was investigated in solution and detailed analysis of the crystal identified a dimer organization which is distinctive from that of other members of the GalR/LacI family.

  6. Id2 reinforces TH1 cell differentiation and inhibits E2A to repress TFH cell differentiation

    Science.gov (United States)

    Shaw, Laura A.; Bélanger, Simon; Omilusik, Kyla D.; Cho, Sunglim; Scott-Browne, James P.; Nance, J. Philip; Goulding, John; Lasorella, Anna; Lu, Li-Fan; Crotty, Shane; Goldrath, Ananda W.

    2016-01-01

    Differentiation of T helper (TH) effector subsets is critical for host protection. E protein transcription factors and Id proteins are important arbiters of T cell development, but their role in differentiation of TH1 and TFH cells is not well understood. TH1 cells showed robust Id2 expression compared to TFH cells, and RNAi depletion of Id2 increased TFH cell frequencies. Further, TH1 cell differentiation was blocked by Id2 deficiency, leading to E protein-dependent accumulation of effector cells with mixed characteristics during viral infection and severely impaired generation of TH1 cells following Toxoplasma gondii infection. The TFH-defining transcriptional repressor Bcl6 bound the Id2 locus, providing a mechanism for the bimodal Id2 expression and reciprocal development of TH1 and TFH cell fates. PMID:27213691

  7. The effector repertoire of Fusarium oxysporum determines the tomato xylem proteome composition following infection

    Directory of Open Access Journals (Sweden)

    Fleur eGawehns

    2015-11-01

    Full Text Available Plant pathogens secrete small proteins, of which some are effectors that promote infection. During colonization of the tomato xylem vessels the fungus Fusarium oxysporum f. sp. lycopersici (Fol secretes small proteins that are referred to as SIX (Secreted In Xylem proteins. Of these, Six1 (Avr3, Six3 (Avr2, Six5 and Six6 are required for full virulence, denoting them as effectors. To investigate their activities in the plant, the xylem sap proteome of plants inoculated with Fol wild-type or either AVR2, AVR3, SIX2, SIX5 or SIX6 knockout strains was analyzed with nano-Liquid Chromatography-Mass Spectrometry (nLC-MSMS. Compared to mock-inoculated sap 12 additional plant proteins appeared while 45 proteins were no longer detectable in the xylem sap of Fol-infected plants. Of the 285 proteins found in both uninfected and infected plants the abundance of 258 proteins changed significantly following infection. The xylem sap proteome of plants infected with four Fol effector knockout strains differed significantly from plants infected with wild-type Fol, while that of the SIX2-knockout inoculated plants remained unchanged. Besides an altered abundance of a core set of 24 differentially accumulated proteins (DAPs, each of the four effector knockout strains affected specifically the abundance of a subset of DAPs. Hence, Fol effectors have both unique and shared effects on the composition of the tomato xylem sap proteome.

  8. Evidence that steroid 5alpha-reductase isozyme genes are differentially methylated in human lymphocytes.

    Science.gov (United States)

    Rodríguez-Dorantes, M; Lizano-Soberón, M; Camacho-Arroyo, I; Calzada-León, R; Morimoto, S; Téllez-Ascencio, N; Cerbón, M A

    2002-03-01

    The synthesis of dihydrotestosterone (DHT) is catalyzed by steroid 5alpha-reductase isozymes 1 and 2, and this function determines the development of the male phenotype during embriogenesis and the growth of androgen sensitive tissues during puberty. The aim of this study was to determine the cytosine methylation status of 5alpha-reductase isozymes types 1 and 2 genes in normal and in 5alpha-reductase deficient men. Genomic DNA was obtained from lymphocytes of both normal subjects and patients with primary 5alpha-reductase deficiency due to point mutations in 5alpha-reductase 2 gene. Southern blot analysis of 5alpha-reductase types 1 and 2 genes from DNA samples digested with HpaII presented a different cytosine methylation pattern compared to that observed with its isoschizomer MspI, indicating that both genes are methylated in CCGG sequences. The analysis of 5alpha-reductase 1 gene from DNA samples digested with Sau3AI and its isoschizomer MboI which recognize methylation in GATC sequences showed an identical methylation pattern. In contrast, 5alpha-reductase 2 gene digested with Sau3AI presented a different methylation pattern to that of the samples digested with MboI, indicating that steroid 5alpha-reductase 2 gene possess methylated cytosines in GATC sequences. Analysis of exon 4 of 5alpha-reductase 2 gene after metabisulfite PCR showed that normal and deficient subjects present a different methylation pattern, being more methylated in patients with 5alpha-reductase 2 mutated gene. The overall results suggest that 5alpha-reductase genes 1 and 2 are differentially methylated in lymphocytes from normal and 5alpha-reductase deficient patients. Moreover, the extensive cytosine methylation pattern observed in exon 4 of 5alpha-reductase 2 gene in deficient patients, points out to an increased rate of mutations in this gene.

  9. Killing of targets by effector CD8 T cells in the mouse spleen follows the law of mass action

    Energy Technology Data Exchange (ETDEWEB)

    Ganusov, Vitaly V [Los Alamos National Laboratory

    2009-01-01

    In contrast with antibody-based vaccines, it has been difficult to measure the efficacy of T cell-based vaccines and to correlate the efficacy of CD8 T cell responses with protection again viral infections. In part, this difficulty is due to poor understanding of the in vivo efficacy of CD8 T cells produced by vaccination. Using a: recently developed experimental method of in vivo cytotoxicity we have investigated quantitative aspects of killing of peptide-pulsed targets by effector and memory CD8 T cells, specific to three epitopes of lymphocytic choriomeningitis virus (LCMV), in the mouse spleen. By analyzing data on killing of targets with varying number of epitope-specific effector and memory CD8 T cells, we find that killing of targets by effectors follows the law of mass-action, that is the death rate of peptide-pulsed targets is proportional to the frequency of CTLs in the spleen. In contrast, killing of targets by memory CD8 T cells does not follow the mass action law because the death rate of targets saturates at high frequencies of memory CD8 T cells. For both effector and memory cells, we also find little support for the killing term that includes the decrease of the death rate of targets with target cell density. Interestingly, our analysis suggests that at low CD8 T cell frequencies, memory CD8 T cells on the per capita basis are more efficient at killing peptide-pulsed targets than effectors, but at high frequencies, effectors are more efficient killers than memory T cells. Comparison of the estimated killing efficacy of effector T cells with the value that is predicted from theoretical physics and based on motility of T cells in lymphoid tissues, suggests that limiting step in the killing of peptide-pulsed targets is delivering the lethal hit and not finding the target. Our results thus form a basis for quantitative understanding of the process of killing of virus-infected cells by T cell responses in tissues and can be used to correlate the

  10. Impairment of lymphocyte adhesion to cultured fibroblasts and endothelial cells by γ-irradiation

    International Nuclear Information System (INIS)

    Piela-Smith, T.H.; Aneiro, L.; Nuveen, E.; Korn, J.H.; Aune, T.

    1992-01-01

    A critical component of immune responsiveness is the localization of effector cells at sites of inflammatory lesions. Adhesive molecules that may play a role in this process have been described on the surfaces of both lymphocytes and connective tissue cells. Adhesive interactions of T lymphocytes with fibroblasts or endothelial cells can be inhibited by preincubation of the fibroblasts or endothelial cells with antibody to intercellular adhesion molecule 1 (CD54) or by preincubation of the T cells with antibody to lymphocyte function-associated Ag 1 (CD11a/CD18), molecules shown to be important in several other cell-cell adhesion interactions. Here the authors show that γ-irradiation of human T lymphocytes impaired their ability to adhere to both fibroblasts and endothelial cells. This impairment was not associated with a loss of cell viability or of cell surface lymphocyte function-associated Ag 1 expression. γ-Irradiation of T cells is known to result in the activation of ADP-ribosyltransferase, an enzyme involved in DNA strand-break repair, causing subsequent depletion of cellular nicotinamide adenine dinucleotide (NAD) pools by increasing NAD consumption for poly(ADP-ribose) formation. Preincubation of T cells with either nicotinamide or 3-aminobenzamide, both known inhibitors of ADP-ribosyltransferase, completely reversed the suppressive effects of γ-irradiation on T cell adhesion. The maintenance of adhesion was accompanied by inhibition of irradiation-induced depletion of cellular NAD. These experiments suggest that the impairment of cellular immune function after irradiation in vivo may be caused, in part, by defective T cell emigration and localization at inflammatory sites. 44 refs., 5 figs., 3 tabs

  11. Inorganic arsenic represses interleukin-17A expression in human activated Th17 lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Morzadec, Claudie; Macoch, Mélinda; Robineau, Marc; Sparfel, Lydie [UMR INSERM U1085, Institut de Recherche sur la Santé, l' Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France); Fardel, Olivier [UMR INSERM U1085, Institut de Recherche sur la Santé, l' Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France); Pôle Biologie, Centre Hospitalier Universitaire (CHU) Rennes, 2 rue Henri Le Guilloux, 35033 Rennes (France); Vernhet, Laurent, E-mail: laurent.vernhet@univ-rennes1.fr [UMR INSERM U1085, Institut de Recherche sur la Santé, l' Environnement et le Travail (IRSET), Université de Rennes 1, 2 avenue du Professeur Léon Bernard, 35043 Rennes (France)

    2012-08-01

    Trivalent inorganic arsenic [As(III)] is an efficient anticancer agent used to treat patients suffering from acute promyelocytic leukemia. Recently, experimental studies have clearly demonstrated that this metalloid can also cure lymphoproliferative and/or pro-inflammatory syndromes in different murine models of chronic immune-mediated diseases. T helper (Th) 1 and Th17 lymphocytes play a central role in development of these diseases, in mice and humans, especially by secreting the potent pro-inflammatory cytokine interferon-γ and IL-17A, respectively. As(III) impairs basic functions of human T cells but its ability to modulate secretion of pro-inflammatory cytokines by differentiated Th lymphocytes is unknown. In the present study, we demonstrate that As(III), used at concentrations clinically achievable in plasma of patients, has no effect on the secretion of interferon-γ from Th1 cells but almost totally blocks the expression and the release of IL-17A from human Th17 lymphocytes co-stimulated for five days with anti-CD3 and anti-CD28 antibodies, in the presence of differentiating cytokines. In addition, As(III) specifically reduces mRNA levels of the retinoic-related orphan receptor (ROR)C gene which encodes RORγt, a key transcription factor controlling optimal IL-17 expression in fully differentiated Th17 cells. The metalloid also blocks initial expression of IL-17 gene induced by the co-stimulation, probably in part by impairing activation of the JNK/c-Jun pathway. In conclusion, our results demonstrate that As(III) represses expression of the major pro-inflammatory cytokine IL-17A produced by human Th17 lymphocytes, thus strengthening the idea that As(III) may be useful to treat inflammatory immune-mediated diseases in humans. -- Highlights: ► Arsenic inhibits secretion of IL-17A from human naïve and memory Th17 lymphocytes. ► Arsenic represses early expression of IL-17A gene in human activated T lymphocytes. ► Arsenic interferes with activation of

  12. Effect of human bone marrow mesenchymal stromal cells on cytokine production by peripheral blood naive, memory, and effector T cells.

    Science.gov (United States)

    Laranjeira, Paula; Pedrosa, Monia; Pedreiro, Susana; Gomes, Joana; Martinho, Antonio; Antunes, Brigida; Ribeiro, Tania; Santos, Francisco; Trindade, Helder; Paiva, Artur

    2015-01-05

    The different distribution of T cells among activation/differentiation stages in immune disorders may condition the outcome of mesenchymal stromal cell (MSC)-based therapies. Indeed, the effect of MSCs in the different functional compartments of T cells is not completely elucidated. We investigated the effect of human bone marrow MSCs on naturally occurring peripheral blood functional compartments of CD4(+) and CD8(+) T cells: naive, central memory, effector memory, and effector compartments. For that, mononuclear cells (MNCs) stimulated with phorbol myristate acetate (PMA) plus ionomycin were cultured in the absence/presence of MSCs. The percentage of cells expressing tumor necrosis factor-alpha (TNF-α), interferon gamma (IFNγ), and interleukin-2 (IL-2), IL-17, IL-9, and IL-6 and the amount of cytokine produced were assessed by flow cytometry. mRNA levels of IL-4, IL-10, transforming growth factor-beta (TGF-β), and cytotoxic T-lymphocyte-associated protein 4 (CTLA4) in purified CD4(+) and CD8(+) T cells, and phenotypic and mRNA expression changes induced by PMA + ionomycin stimulation in MSCs, were also evaluated. MSCs induced the reduction of the percentage of CD4(+) and CD8(+) T cells producing TNF-α, IFNγ, and IL-2 in all functional compartments, except for naive IFNγ(+)CD4(+) T cells. This inhibitory effect differentially affected CD4(+) and CD8(+) T cells as well as the T-cell functional compartments; remarkably, different cytokines showed distinct patterns of inhibition regarding both the percentage of producing cells and the amount of cytokine produced. Likewise, the percentages of IL-17(+), IL-17(+)TNF-α(+), and IL-9(+) within CD4(+) and CD8(+) T cells and of IL-6(+)CD4(+) T cells were decreased in MNC-MSC co-cultures. MSCs decreased IL-10 and increased IL-4 mRNA expression in stimulated CD4(+) and CD8(+) T cells, whereas TGF-β was reduced in CD8(+) and augmented in CD4(+) T cells, with no changes for CTLA4. Finally, PMA

  13. AMP-activated protein kinase regulates lymphocyte responses to metabolic stress but is largely dispensable for immune cell development and function.

    Science.gov (United States)

    Mayer, Alice; Denanglaire, Sébastien; Viollet, Benoit; Leo, Oberdan; Andris, Fabienne

    2008-04-01

    AMP-activated protein kinase (AMPK), a phylogenetically conserved serine/threonine protein kinase, represents an energy sensor able to adapt cellular metabolism in response to nutritional environmental variations. TCR stimulation activates AMPK, a regulatory event that is known to stimulate ATP-producing processes, possibly in anticipation of the increased energetic needs associated with cell division and expression of effector function. Taking advantage of the selective expression of the AMPKalpha1 catalytic subunit in lymphoid cells, we have analyzed the in vitro and in vivo capacity of lymphocytes lacking AMPK activity (AMPKalpha1-KO cells) to respond to metabolic stress and to initiate and sustain an immune response. AMPKalpha1-KO cells displayed increasing sensitivity to energetic stress in vitro, and were found unable to maintain adequate ATP levels in response to ATP synthase inhibition. These cells were, however, able to respond to antigen stimulation in vitro, as shown by optimal proliferation and cytokine production. Similarly, AMPKalpha1-KO mice were fully immunocompetent in vivo and displayed normal cell proliferation, humoral, cytotoxic and delayed-type hypersensitivity (DTH) responses following antigen injection. In conclusion, AMPK represents an important enzyme allowing lymphocytes to resist a mild energy crisis in vitro, but is largely dispensable for activation and expression of effector function in response to antigen stimulation.

  14. Mtb-specific CD27low CD4 T cells as markers of lung tissue destruction during pulmonary tuberculosis in humans.

    Science.gov (United States)

    Nikitina, Irina Yu; Kondratuk, Natalya A; Kosmiadi, George A; Amansahedov, Rasul B; Vasilyeva, Irina A; Ganusov, Vitaly V; Lyadova, Irina V

    2012-01-01

    Effector CD4 T cells represent a key component of the host's anti-tuberculosis immune defense. Successful differentiation and functioning of effector lymphocytes protects the host against severe M. tuberculosis (Mtb) infection. On the other hand, effector T cell differentiation depends on disease severity/activity, as T cell responses are driven by antigenic and inflammatory stimuli released during infection. Thus, tuberculosis (TB) progression and the degree of effector CD4 T cell differentiation are interrelated, but the relationships are complex and not well understood. We have analyzed an association between the degree of Mtb-specific CD4 T cell differentiation and severity/activity of pulmonary TB infection. The degree of CD4 T cell differentiation was assessed by measuring the percentages of highly differentiated CD27(low) cells within a population of Mtb- specific CD4 T lymphocytes ("CD27(low)IFN-γ(+)" cells). The percentages of CD27(low)IFN-γ+ cells were low in healthy donors (median, 33.1%) and TB contacts (21.8%) but increased in TB patients (47.3%, p76%), but varied in blood (12-92%). The major correlate for the accumulation of CD27(low)IFN-γ(+) cells in blood was lung destruction (r = 0.65, p = 2.7 × 10(-7)). A cutoff of 47% of CD27(low)IFN-γ(+) cells discriminated patients with high and low degree of lung destruction (sensitivity 89%, specificity 74%); a decline in CD27(low)IFN-γ(+)cells following TB therapy correlated with repair and/or reduction of lung destruction (ppulmonary TB. Accumulation of CD27(low)IFN-γ(+) cells in the blood is associated with lung destruction. The findings indicate that there is no deficiency in CD4 T cell differentiation during TB; evaluation of CD27(low)IFN-γ(+) cells provides a valuable means to assess TB activity, lung destruction, and tissue repair following TB therapy.

  15. Anaplasma phagocytophilum-Related Defects in CD8, NKT, and NK Lymphocyte Cytotoxicity

    Directory of Open Access Journals (Sweden)

    Diana G. Scorpio

    2018-04-01

    Full Text Available Human granulocytic anaplasmosis, caused by the tick-transmitted Anaplasma phagocytophilum, is not controlled by innate immunity, and induces a proinflammatory disease state with innate immune cell activation. In A. phagocytophilum murine infection models, hepatic injury occurs with production of IFNγ thought to be derived from NK, NKT cells, and CD8 T lymphocytes. Specific A. phagocytophilum ligands that drive inflammation and disease are not known, but suggest a clinical and pathophysiologic basis strikingly like macrophage activation syndrome (MAS and hemophagocytic syndrome (HPS. We studied in vivo responses of NK, NKT, and CD8 T lymphocytes from infected animals for correlates of lymphocyte-mediated cytotoxicity and examined in vitro interactions with A. phagocytophilum-loaded antigen-presenting cells (APCs. Murine splenocytes were examined and found deficient in cytotoxicity as determined by CD107a expression in vitro for specific CTL effector subsets as determined by flow cytometry. Moreover, A. phagocytophilum-loaded APCs did not lead to IFNγ production among CTLs in vitro. These findings support the concept of impaired cytotoxicity with A. phagocytophilum presentation by APCs that express MHC class I and that interact with innate and adaptive immune cells with or after infection. The findings strengthen the concept of an enhanced proinflammatory phenotype, such as MAS and HPS disease states as the basis of disease and severity with A. phagocytophilum infection, and perhaps by other obligate intracellular bacteria.

  16. Fish Lymphocytes: An Evolutionary Equivalent of Mammalian Innate-Like Lymphocytes?

    Directory of Open Access Journals (Sweden)

    Giuseppe Scapigliati

    2018-05-01

    Full Text Available Lymphocytes are the responsible of adaptive responses, as they are classically described, but evidence shows that subpopulations of mammalian lymphocytes may behave as innate-like cells, engaging non-self rapidly and without antigen presentation. The innate-like lymphocytes of mammals have been mainly identified as γδT cells and B1-B cells, exert their activities principally in mucosal tissues, may be involved in human pathologies and their functions and tissue(s of origin are not fully understood. Due to similarities in the morphology and immunobiology of immune system between fish and mammals, and to the uniqueness of having free-living larval stages where the development can be precisely monitored and engineered, teleost fish are proposed as an experimental model to investigate human immunity. However, the homology between fish lymphocytes and mammalian innate-like lymphocytes is an issue poorly considered in comparative immunology. Increasing experimental evidence suggests that fish lymphocytes could have developmental, morphological, and functional features in common with innate-like lymphocytes of mammals. Despite such similarities, information on possible links between conventional fish lymphocytes and mammalian innate-like lymphocytes is missing. The aim of this review is to summarize and describe available findings about the similarities between fish lymphocytes and mammalian innate-like lymphocytes, supporting the hypothesis that mammalian γδT cells and B1-B cells could be evolutionarily related to fish lymphocytes.

  17. T-dependence of human B lymphocyte proliferative response to mitogens.

    Science.gov (United States)

    Brochier, J; Samarut, C; Gueho, J P; Revillard, J P

    1976-01-01

    Human peripheral blood and tonsil lymphocytes were fractionated on anti-Ig-coated Sephadex columns or by centrifugation after rosetting with native sheep erythrocytes. Both methods allowed the recovery of B and T-enriched populations the purity of which was checked by fluorescein-labelled anti-Ig serum, E and EAC rosette formation, and heterologous antisera specific for B or T lymphocytes. The proliferative response of T cells to PHA, Con A, PWM, and ALS was not found different from that of unfractionated cells, whereas no response of the B cells could be observed to these mitogens providing that no contaminating T cells were present. Addition of T lymphocytes to these unresponsive B cells allowed them to respond to phytomitogens, but not to ALS. X-irradiated T cells could, to some extent, replace the diving T lymphocytes; no T-replacing factor could be found in cell-free supernatants from T cells, whether or not they had been activated by mitrogens. This model of B-T cooperation appears useful for studying the differentiation and maturation of human B lymphocytes.

  18. Fate of thymic lymphocytes. [/sup 125/IudR and /sup 3/HTdR tracer studies in mice

    Energy Technology Data Exchange (ETDEWEB)

    Laissue, J A; Chanana, A D; Cronkite, E P; Joel, D D

    1976-01-01

    Data are summarized from a number of studies on the fate of thymic lymphocytes. Results are reported from studies in mice in which /sup 125/IudR and /sup 3/HTdR were used as tracers to study the production, maturation, migration, and life span of thymic lymphocytes. It is pointed out that thymus-derived cells constitute the majority of recirculating lymphocytes and that peripheral, differentiated thymus-derived lymphocytes exhibit a number of immunological functions. 114 references.

  19. Systematic Identification of Intracellular-Translocated Candidate Effectors in Edwardsiella piscicida

    Directory of Open Access Journals (Sweden)

    Lingzhi Zhang

    2018-02-01

    Full Text Available Many bacterial pathogens inject effectors directly into host cells to target a variety of host cellular processes and promote bacterial dissemination and survival. Identifying the bacterial effectors and elucidating their functions are central to understanding the molecular pathogenesis of these pathogens. Edwardsiella piscicida is a pathogen with a wide host range, and very few of its effectors have been identified to date. Here, based on the genes significantly regulated by macrophage infection, we identified 25 intracellular translocation-positive candidate effectors, including all five previously reported effectors, namely EseG, EseJ, EseH, EseK, and EvpP. A subsequent secretion analysis revealed diverse secretion patterns for the 25 effector candidates, suggesting that multiple transport pathways were involved in the internalization of these candidate effectors. Further, we identified two novel type VI secretion system (T6SS putative effectors and three outer membrane vesicles (OMV-dependent putative effectors among the candidate effectors described above, and further analyzed their contribution to bacterial virulence in a zebrafish model. This work demonstrates an effective approach for screening bacterial effectors and expands the effectors repertoire in E. piscicida.

  20. Epigenetic landscapes reveal transcription factors that regulate CD8+ T cell differentiation.

    Science.gov (United States)

    Yu, Bingfei; Zhang, Kai; Milner, J Justin; Toma, Clara; Chen, Runqiang; Scott-Browne, James P; Pereira, Renata M; Crotty, Shane; Chang, John T; Pipkin, Matthew E; Wang, Wei; Goldrath, Ananda W

    2017-05-01

    Dynamic changes in the expression of transcription factors (TFs) can influence the specification of distinct CD8 + T cell fates, but the observation of equivalent expression of TFs among differentially fated precursor cells suggests additional underlying mechanisms. Here we profiled the genome-wide histone modifications, open chromatin and gene expression of naive, terminal-effector, memory-precursor and memory CD8 + T cell populations induced during the in vivo response to bacterial infection. Integration of these data suggested that the expression and binding of TFs contributed to the establishment of subset-specific enhancers during differentiation. We developed a new bioinformatics method using the PageRank algorithm to reveal key TFs that influence the generation of effector and memory populations. The TFs YY1 and Nr3c1, both constitutively expressed during CD8 + T cell differentiation, regulated the formation of terminal-effector cell fates and memory-precursor cell fates, respectively. Our data define the epigenetic landscape of differentiation intermediates and facilitate the identification of TFs with previously unappreciated roles in CD8 + T cell differentiation.

  1. Effector-Triggered Self-Replication in Coupled Subsystems.

    Science.gov (United States)

    Komáromy, Dávid; Tezcan, Meniz; Schaeffer, Gaël; Marić, Ivana; Otto, Sijbren

    2017-11-13

    In living systems processes like genome duplication and cell division are carefully synchronized through subsystem coupling. If we are to create life de novo, similar control over essential processes such as self-replication need to be developed. Here we report that coupling two dynamic combinatorial subsystems, featuring two separate building blocks, enables effector-mediated control over self-replication. The subsystem based on the first building block shows only self-replication, whereas that based on the second one is solely responsive toward a specific external effector molecule. Mixing the subsystems arrests replication until the effector molecule is added, resulting in the formation of a host-effector complex and the liberation of the building block that subsequently engages in self-replication. The onset, rate and extent of self-replication is controlled by the amount of effector present. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Id2 reinforces TH1 differentiation and inhibits E2A to repress TFH differentiation.

    Science.gov (United States)

    Shaw, Laura A; Bélanger, Simon; Omilusik, Kyla D; Cho, Sunglim; Scott-Browne, James P; Nance, J Philip; Goulding, John; Lasorella, Anna; Lu, Li-Fan; Crotty, Shane; Goldrath, Ananda W

    2016-07-01

    The differentiation of helper T cells into effector subsets is critical to host protection. Transcription factors of the E-protein and Id families are important arbiters of T cell development, but their role in the differentiation of the TH1 and TFH subsets of helper T cells is not well understood. Here, TH1 cells showed more robust Id2 expression than that of TFH cells, and depletion of Id2 via RNA-mediated interference increased the frequency of TFH cells. Furthermore, TH1 differentiation was blocked by Id2 deficiency, which led to E-protein-dependent accumulation of effector cells with mixed characteristics during viral infection and severely impaired the generation of TH1 cells following infection with Toxoplasma gondii. The TFH cell-defining transcriptional repressor Bcl6 bound the Id2 locus, which provides a mechanism for the bimodal Id2 expression and reciprocal development of TH1 cells and TFH cells.

  3. TNFR2 expression on CD25hiFOXP3+ T cells induced upon TCR stimulation of CD4 T cells identifies maximal cytokine-producing effectors.

    Directory of Open Access Journals (Sweden)

    Chindu eGovindaraj

    2013-08-01

    Full Text Available In this study, we show that CD25hiTNFR2+ cells can be rapidly generated in vitro from circulating CD4 lymphocytes by polyclonal stimuli anti-CD3 in the presence of anti-CD28. The in vitro induced CD25hiTNFR2+ T cells express a conventional Treg phenotype FOXP3+CTLA4+CD127lo/-, but produce effector and immunoregulatory cytokines including IL-2, IL-10 and IFN-g. These induced CD25hiTNFR2+ T cells do not suppress target cell proliferation, but enhance it instead. Thus the CD25hiTNFR2+ phenotype induced rapidly following CD3/28 cross linking of CD4 T cells identifies cells with maximal proliferative and effector cytokine producing capability. The in vivo counterpart of this cell population may play an important role in immune response initiation.

  4. Lymphocytic subsets and low-dose exposure

    International Nuclear Information System (INIS)

    Tuschl, H.; Kovac, R.; Eybl, E.

    1993-03-01

    The present investigations proved the differential radiosensitivity of lymphocytic subpopulations: From in vivo and in vitro irradiations it may be followed that the most sensitive subset are CD8 positive suppressor T cells. CD4/CD8 ratios are increased both in peripheral blood and after mitogen stimulation of lymphocytes of exposed persons. The decrease in B cells is pronounced only at higher radiation doses. Though the rate of DNA synthesis after mitogen stimulation was reduced in some exposed persons, that was no general phenomenon. Especially after tritium exposure, the observed lymphopenia correlated with an increased stimulation by PHA and an increased rate of DNA synthesis in some probands. Thus the present investigations indicate that - despite an inhibition of some immune parameters by radioexposure - the body is able to maintain its immunological homoeostasis. (authors)

  5. Chronic Alcohol Ingestion Delays T Cell Activation and Effector Function in Sepsis.

    Science.gov (United States)

    Margoles, Lindsay M; Mittal, Rohit; Klingensmith, Nathan J; Lyons, John D; Liang, Zhe; Serbanescu, Mara A; Wagener, Maylene E; Coopersmith, Craig M; Ford, Mandy L

    2016-01-01

    Sepsis is the leading cause of death in intensive care units in the US, and it is known that chronic alcohol use is associated with higher incidence of sepsis, longer ICU stays, and higher mortality from sepsis. Both sepsis and chronic alcohol use are associated with immune deficits such as decreased lymphocyte numbers, impaired innate immunity, delayed-type hypersensitivity reactions, and susceptibility to infections; however, understanding of specific pathways of interaction or synergy between these two states of immune dysregulation is lacking. This study therefore sought to elucidate mechanisms underlying the immune dysregulation observed during sepsis in the setting of chronic alcohol exposure. Using a murine model of chronic ethanol ingestion followed by sepsis induction via cecal ligation and puncture, we determined that while CD4+ and CD8+ T cells isolated from alcohol fed mice eventually expressed the same cellular activation markers (CD44, CD69, and CD43) and effector molecules (IFN-γ, TNF) as their water fed counterparts, there was an overall delay in the acquisition of these phenotypes. This early lag in T cell activation was associated with significantly reduced IL-2 production at a later timepoint in both the CD4+ and CD8+ T cell compartments in alcohol sepsis, as well as with a reduced accumulation of CD8dim activated effectors. Taken together, these data suggest that delayed T cell activation may result in qualitative differences in the immune response to sepsis in the setting of chronic alcohol ingestion.

  6. Role of OCT-1 and partner proteins in T cell differentiation.

    Science.gov (United States)

    Hwang, Soo Seok; Kim, Lark Kyun; Lee, Gap Ryol; Flavell, Richard A

    2016-06-01

    The understanding of CD4 T cell differentiation gives important insights into the control of immune responses against various pathogens and in autoimmune diseases. Naïve CD4 T cells become effector T cells in response to antigen stimulation in combination with various environmental cytokine stimuli. Several transcription factors and cis-regulatory regions have been identified to regulate epigenetic processes on chromatin, to allow the production of proper effector cytokines during CD4 T cell differentiation. OCT-1 (Pou2f1) is well known as a widely expressed transcription factor in most tissues and cells. Although the importance of OCT-1 has been emphasized during development and differentiation, its detailed molecular underpinning and precise role are poorly understood. Recently, a series of studies have reported that OCT-1 plays a critical role in CD4 T cells through regulating gene expression during differentiation and mediating long-range chromosomal interactions. In this review, we will describe the role of OCT-1 in CD4 T cell differentiation and discuss how this factor orchestrates the fate and function of CD4 effector T cells. Copyright © 2016. Published by Elsevier B.V.

  7. Low interleukin-2 concentration favors generation of early memory T cells over effector phenotypes during chimeric antigen receptor T-cell expansion.

    Science.gov (United States)

    Kaartinen, Tanja; Luostarinen, Annu; Maliniemi, Pilvi; Keto, Joni; Arvas, Mikko; Belt, Heini; Koponen, Jonna; Loskog, Angelica; Mustjoki, Satu; Porkka, Kimmo; Ylä-Herttuala, Seppo; Korhonen, Matti

    2017-06-01

    Adoptive T-cell therapy offers new options for cancer treatment. Clinical results suggest that T-cell persistence, depending on T-cell memory, improves efficacy. The use of interleukin (IL)-2 for in vitro T-cell expansion is not straightforward because it drives effector T-cell differentiation but does not promote the formation of T-cell memory. We have developed a cost-effective expansion protocol for chimeric antigen receptor (CAR) T cells with an early memory phenotype. Lymphocytes were transduced with third-generation lentiviral vectors and expanded using CD3/CD28 microbeads. The effects of altering the IL-2 supplementation (0-300 IU/mL) and length of expansion (10-20 days) on the phenotype of the T-cell products were analyzed. High IL-2 levels led to a decrease in overall generation of early memory T cells by both decreasing central memory T cells and augmenting effectors. T memory stem cells (T SCM , CD95 + CD45RO - CD45RA + CD27 + ) were present variably during T-cell expansion. However, their presence was not IL-2 dependent but was linked to expansion kinetics. CD19-CAR T cells generated in these conditions displayed in vitro antileukemic activity. In summary, production of CAR T cells without any cytokine supplementation yielded the highest proportion of early memory T cells, provided a 10-fold cell expansion and the cells were functionally potent. The number of early memory T cells in a T-cell preparation can be increased by simply reducing the amount of IL-2 and limiting the length of T-cell expansion, providing cells with potentially higher in vivo performance. These findings are significant for robust and cost-effective T-cell manufacturing. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  8. Different Subsets of T Cells, Memory, Effector Functions, and CAR-T Immunotherapy.

    Science.gov (United States)

    Golubovskaya, Vita; Wu, Lijun

    2016-03-15

    This review is focused on different subsets of T cells: CD4 and CD8, memory and effector functions, and their role in CAR-T therapy--a cellular adoptive immunotherapy with T cells expressing chimeric antigen receptor. The CAR-T cells recognize tumor antigens and induce cytotoxic activities against tumor cells. Recently, differences in T cell functions and the role of memory and effector T cells were shown to be important in CAR-T cell immunotherapy. The CD4⁺ subsets (Th1, Th2, Th9, Th17, Th22, Treg, and Tfh) and CD8⁺ memory and effector subsets differ in extra-cellular (CD25, CD45RO, CD45RA, CCR-7, L-Selectin [CD62L], etc.); intracellular markers (FOXP3); epigenetic and genetic programs; and metabolic pathways (catabolic or anabolic); and these differences can be modulated to improve CAR-T therapy. In addition, CD4⁺ Treg cells suppress the efficacy of CAR-T cell therapy, and different approaches to overcome this suppression are discussed in this review. Thus, next-generation CAR-T immunotherapy can be improved, based on our knowledge of T cell subsets functions, differentiation, proliferation, and signaling pathways to generate more active CAR-T cells against tumors.

  9. Different Subsets of T Cells, Memory, Effector Functions, and CAR-T Immunotherapy

    Directory of Open Access Journals (Sweden)

    Vita Golubovskaya

    2016-03-01

    Full Text Available This review is focused on different subsets of T cells: CD4 and CD8, memory and effector functions, and their role in CAR-T therapy––a cellular adoptive immunotherapy with T cells expressing chimeric antigen receptor. The CAR-T cells recognize tumor antigens and induce cytotoxic activities against tumor cells. Recently, differences in T cell functions and the role of memory and effector T cells were shown to be important in CAR-T cell immunotherapy. The CD4+ subsets (Th1, Th2, Th9, Th17, Th22, Treg, and Tfh and CD8+ memory and effector subsets differ in extra-cellular (CD25, CD45RO, CD45RA, CCR-7, L-Selectin [CD62L], etc.; intracellular markers (FOXP3; epigenetic and genetic programs; and metabolic pathways (catabolic or anabolic; and these differences can be modulated to improve CAR-T therapy. In addition, CD4+ Treg cells suppress the efficacy of CAR-T cell therapy, and different approaches to overcome this suppression are discussed in this review. Thus, next-generation CAR-T immunotherapy can be improved, based on our knowledge of T cell subsets functions, differentiation, proliferation, and signaling pathways to generate more active CAR-T cells against tumors.

  10. Differential effector responses by circulating/blood and tissue/peritoneal neutrophils following burn combined with Enterococcus faecalis infection.

    Science.gov (United States)

    Fazal, Nadeem; Shelip, Alla; Siddiqui, Erum; Ali, Ashraf; Azim, Anser C; Al-Ghoul, Walid M

    2012-03-01

    Recently we found that superimposition of Enterococcus faecalis infection on burn injury caused an eruption of host mortality not seen with either individual challenge. We hypothesized that the Enterococcus bacteria, and/or factors related to these organisms, aggravate burn-induced modulations in host defense by neutrophils. Our study focuses on alterations in neutrophils' oxidative, proteolytic, and adhesive functions and transendothelial migration of neutrophils in burn rats inoculated with E. faecalis. Rats were subjected to burn (30% total body surface area) and then intra-abdominally inoculated with E. faecalis (10(4)CFU kg(-1) b.w). Polymorphonuclear neutrophils (PMNs) were harvested from circulating/blood and tissue/peritoneal cavity at day-2 post injury. Extracellular release of O(-)(2) anion production was determined by luminometry, and intracellular production of reactive oxygen species was measured by digital imaging technique. Fluoroscan analysis and confocal microscopy determined intracellular elastase production. The expression of adhesion molecule CD11b/CD18 was performed by flow cytometry. Calcein AM-labeled PMNs were co-cultured with TNF-α-stimulated rat lung microvascular endothelial cells, and their ability to adhere was assessed by fluorometry and digital imaging and finally, chemotaxis was measured by neutrophil transmigration assays. The results showed differential effector responses by circulatory and/or tissue PMNs. Tissue/peritoneal PMNs produced more O(-)(2), less intracellular elastase, and increased expression of CD11b/CD18 accompanied with increased adhesivity of MIP-2-stimulated PMNs to endothelial cells as compared to circulatory/blood PMNs. This differential effect was more pronounced following burn plus E. faecalis infection, indicating that the combined injury changed neutrophil functions. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  11. Selective effects of alpha interferon on human T-lymphocyte subsets during mixed lymphocyte cultures

    DEFF Research Database (Denmark)

    Hokland, M; Hokland, P; Heron, I

    1983-01-01

    Mixed lymphocyte reaction (MLR) cultures of human lymphocyte subsets with or without the addition of physiological doses of human alpha interferon (IFN-alpha) were compared with respect to surface marker phenotypes and proliferative capacities of the responder cells. A selective depression on the T...... T4 cells and decreased numbers of T4 cells harvested from IFN MLRs (days 5-6 of culture). In contrast, it was shown that the T8 (cytotoxic/suppressor) subset in MLRs was either not affected or slightly stimulated by the addition of IFN. The depression of the T4 cells by IFN was accompanied...... by a decrease in the number of activated T cells expressing Ia antigens. On the other hand, IFN MLRs contained greater numbers of cells expressing the T10 differentiation antigen. In experiments with purified T-cell subsets the IFN effect was exerted directly on the T4 cells and not mediated by either T8...

  12. Effects of PARP-1 Deficiency on Th1 and Th2 Cell Differentiation

    Directory of Open Access Journals (Sweden)

    M. Sambucci

    2013-01-01

    Full Text Available T cell differentiation to effector Th cells such as Th1 and Th2 requires the integration of multiple synergic and antagonist signals. Poly(ADP-ribosylation is a posttranslational modification of proteins catalyzed by Poly(ADP-ribose polymerases (PARPs. Recently, many reports showed that PARP-1, the prototypical member of the PARP family, plays a role in immune/inflammatory responses. Consistently, its enzymatic inhibition confers protection in several models of immune-mediated diseases, mainly through an inhibitory effect on NF-κB (and NFAT activation. PARP-1 regulates cell functions in many types of immune cells, including dendritic cells, macrophages, and T and B lymphocytes. Our results show that PARP-1KO cells displayed a reduced ability to differentiate in Th2 cells. Under both nonskewing and Th2-polarizing conditions, naïve CD4 cells from PARP-1KO mice generated a reduced frequency of IL-4+ cells, produced less IL-5, and expressed GATA-3 at lower levels compared with cells from wild type mice. Conversely, PARP-1 deficiency did not substantially affect differentiation to Th1 cells. Indeed, the frequency of IFN-γ+ cells as well as IFN-γ production, in nonskewing and Th1-polarizing conditions, was not affected by PARP-1 gene ablation. These findings demonstrate that PARP-1 plays a relevant role in Th2 cell differentiation and it might be a target to be exploited for the modulation of Th2-dependent immune-mediated diseases.

  13. SPRYSEC effector proteins in Globodera rostochiensis

    NARCIS (Netherlands)

    Rehman, S.

    2008-01-01

    Plant pathogens inject so-called effector molecules into the cells of a host plant to promote their growth and reproduction in these hosts. In plant parasitic nematodes, these effector molecules are produced in the salivary glands. The objective of this thesis was to identify and characterize

  14. Uncovering the Legionella genus effector repertoire - strength in diversity and numbers

    Science.gov (United States)

    Burstein, David; Amaro, Francisco; Zusman, Tal; Lifshitz, Ziv; Cohen, Ofir; Gilbert, Jack A; Pupko, Tal; Shuman, Howard A; Segal, Gil

    2016-01-01

    Infection by the human pathogen Legionella pneumophila relies on the translocation of ~300 virulence proteins, termed effectors, which manipulate host-cell processes. However, almost no information exists regarding effectors in other Legionella pathogens. Here we sequenced, assembled and characterized the genomes of 38 Legionella species, and predicted their effector repertoire using a previously validated machine-learning approach. This analysis revealed a treasure trove of 5,885 predicted effectors. The effector repertoire of different Legionella species was found to be largely non-overlapping, and only seven core-effectors were shared among all species studied. Species-specific effectors had atypically low GC content, suggesting exogenous acquisition, possibly from their natural protozoan hosts. Furthermore, we detected numerous novel conserved effector domains, and discovered new domain combinations, which allowed inferring yet undescribed effector functions. The effector collection and network of domain architectures described here can serve as a roadmap for future studies of effector function and evolution. PMID:26752266

  15. Impact of chronic lymphocytic thyroiditis co-existing with differentiated thyroid cancer on the effectiveness of remnants ablation

    International Nuclear Information System (INIS)

    Boughattas, S.; Chatti, K.; Trimeche, M.; Mokni, M.

    2004-01-01

    Full text: Some stages of chronic lymphocytic thyroiditis (CLT) are functionally characterized by an organification defect with large intra thyroid inorganic iodide pool, which can be discharged during perchlorate test. Fluorescent scan study indicates that most patients with CLT have decreased stable iodine store in the thyroid gland. The aim of our study was to investigate the possible consequences of these organification abnormalities during remnants ablation in patients with coexisting differentiated thyroid cancer (DTC) and chronic lymphocytic thyroiditis. We reviewed our series of patients of DTC being followed at the department of nuclear medicine of the university hospital Sahloul. Among the 350 patients with DTC, 30 (8.5%) had histologically proved chronic lymphocytic thyroiditis, with infiltration of the non-tumoral thyroid tissue. A second group of 60 patients (without evidence of lymphocytic infiltration) was selected randomly and used as control. The median of follow-up for these two groups was 4 years. All patients had undergone total thyroidectomy followed by scintigraphy 4-6 weeks later. In patients with thyroid remnants, standard ablative dose of 3.7 GBq of I-131 (100 mCi) was administrated with 6 months duration between all therapies, until the negativity of thyroid bed activity on follow up survey scan performed 48 to 72 hours after administering 2 to 3 mCi of I-131. Thyroglobulin (Tg) serum level was not considered as a criterion of ablation, because of the frequency of anti-thyroid antibodies in CLT. In the group with CLT, 3 patients had negative postoperative neck scintigraphy. Complete ablation was achieved with a single standard dose in 14, two standard doses in 5, and more than 200 mCi in two patients (300 in one and 400 in two). In five patients, ablation is not yet achieved. In the control group, ablation was obtained with 100 mCi in 43 patients, 200 mCi in 9, and 300 mCi in 3. In five patients ablation has not been achieved. Considering

  16. An Alteration of Lymphocytes Subpopulations and Immunoglobulins Levels in Patients with Diabetic Foot Ulcers Infected Particularly by Resistant Pathogens

    Directory of Open Access Journals (Sweden)

    Vladimíra Fejfarová

    2016-01-01

    Full Text Available The aim of our study was to analyse immune abnormalities in patients with chronic infected diabetic foot ulcers (DFUs especially those infected by resistant microorganisms. Methods. 68 patients treated in our foot clinic for infected chronic DFUs with 34 matched diabetic controls were studied. Patients with infected DFUs were subdivided into two subgroups according to the antibiotic sensitivity of causal pathogen: subgroup S infected by sensitive (n=50 and subgroup R by resistant pathogens (n=18. Selected immunological markers were compared between the study groups and subgroups. Results. Patients with infected chronic DFUs had, in comparison with diabetic controls, significantly reduced percentages (p<0.01 and total numbers of lymphocytes (p<0.001 involving B lymphocytes (p<0.01, CD4+ (p<0.01, and CD8+ T cells (p<0.01 and their naive and memory effector cells. Higher levels of IgG (p<0.05 including IgG1 (p<0.001 and IgG3 (p<0.05 were found in patients with DFUs compared to diabetic controls. Serum levels of immunoglobulin subclasses IgG2 and IgG3 correlated negatively with metabolic control (p<0.05. A trend towards an increased frequency of IgG2 deficiency was found in patients with DFUs compared to diabetic controls (22% versus 15%; NS. Subgroup R revealed lower levels of immunoglobulins, especially of IgG4 (p<0.01 in contrast to patients infected by sensitive bacteria. The innate immunity did not differ significantly between the study groups. Conclusion. Our study showed changes mainly in the adaptive immune system represented by low levels of lymphocyte subpopulations and their memory effector cells, and also changes in humoral immunity in patients with DFUs, even those infected by resistant pathogens, in comparison with diabetic controls.

  17. Effector proteins of rust fungi.

    Science.gov (United States)

    Petre, Benjamin; Joly, David L; Duplessis, Sébastien

    2014-01-01

    Rust fungi include many species that are devastating crop pathogens. To develop resistant plants, a better understanding of rust virulence factors, or effector proteins, is needed. Thus far, only six rust effector proteins have been described: AvrP123, AvrP4, AvrL567, AvrM, RTP1, and PGTAUSPE-10-1. Although some are well established model proteins used to investigate mechanisms of immune receptor activation (avirulence activities) or entry into plant cells, how they work inside host tissues to promote fungal growth remains unknown. The genome sequences of four rust fungi (two Melampsoraceae and two Pucciniaceae) have been analyzed so far. Genome-wide analyses of these species, as well as transcriptomics performed on a broader range of rust fungi, revealed hundreds of small secreted proteins considered as rust candidate secreted effector proteins (CSEPs). The rust community now needs high-throughput approaches (effectoromics) to accelerate effector discovery/characterization and to better understand how they function in planta. However, this task is challenging due to the non-amenability of rust pathosystems (obligate biotrophs infecting crop plants) to traditional molecular genetic approaches mainly due to difficulties in culturing these species in vitro. The use of heterologous approaches should be promoted in the future.

  18. IL-7 treatment augments and prolongs sepsis-induced expansion of IL-10-producing B lymphocytes and myeloid-derived suppressor cells.

    Science.gov (United States)

    Kulkarni, Upasana; Herrmenau, Christoph; Win, Stephanie J; Bauer, Michael; Kamradt, Thomas

    2018-01-01

    Immunological dysregulation in sepsis is associated with often lethal secondary infections. Loss of effector cells and an expansion of immunoregulatory cell populations both contribute to sepsis-induced immunosuppression. The extent and duration of this immunosuppression are unknown. Interleukin 7 (IL-7) is important for the maintenance of lymphocytes and can accelerate the reconstitution of effector lymphocytes in sepsis. How IL-7 influences immunosuppressive cell populations is unknown. We have used the mouse model of peritoneal contamination and infection (PCI) to investigate the expansion of immunoregulatory cells as long-term sequelae of sepsis with or without IL-7 treatment. We analysed the frequencies and numbers of regulatory T cells (Tregs), double negative T cells, IL-10 producing B cells and myeloid-derived suppressor cells (MDSCs) for 3.5 months after sepsis induction. Sepsis induced an increase in IL-10+ B cells, which was enhanced and prolonged by IL-7 treatment. An increased frequency of MDSCs in the spleen was still detectable 3.5 months after sepsis induction and this was more pronounced in IL-7-treated mice. MDSCs from septic mice were more potent at suppressing T cell proliferation than MDSCs from control mice. Our data reveal that sepsis induces a long lasting increase in IL-10+ B cells and MDSCs. Late-onset IL-7 treatment augments this increase, which should be relevant for clinical interventions.

  19. LYMPHOCYTIC THYROIDITIS IS ASSOCIATED WITH INCREASED NUMBER OF BENIGN CERVICAL NODES AND FEWER CENTRAL NECK COMPARTMENT METASTATIC LYMPH NODES IN PATIENTS WITH DIFFERENTIATED THYROID CANCER.

    Science.gov (United States)

    Donangelo, Ines; Walts, Ann E; Bresee, Catherine; Braunstein, Glenn D

    2016-10-01

    Whether or not autoimmune thyroid disease influences the progression of differentiated thyroid cancer (DTC) remains controversial. Findings of previous studies are influenced by lead time bias and/or procedure bias selection. These biases can be reduced by studying a single-institution patient population that underwent a similar extent of surgical resection. From a cohort of 660 patients with DTC who underwent thyroidectomy, we retrospectively studied 357 patients who underwent total thyroidectomy and central compartment node dissection (CCND) for DTC between 2003 and 2013. Forty-one percent (140/345) of study patients had lymphocytic thyroiditis (LT), and 30% (91/301) had serum positive for thyroglobulin antibody (TgAb). LT was reported in 78% of the TgAb-positive cases. Sixty percent (213/357) of cases had metastatic thyroid carcinoma in 1 or more neck lymph nodes (55% [198/357] central compartment, and 22% [77/356] lateral compartment). Patients with LT had fewer metastatic cervical lymph nodes than those with no LT (2.7 ± 4.7 vs 3.5 ± 4.8, respectively, P = .0285). Patients with positive TgAb and thyroiditis had a larger number of benign cervical lymph nodes removed than those with negative TgAb or no LT. No significant difference was observed in age, tumor size, multifocality, extrathyroidal extension, vascular invasion, or frequency of cervical lymph node metastasis between TgAb-negative and -positive cases or between cases with and without LT. Lymphocytic thyroiditis is associated with fewer central neck compartment metastatic lymph nodes and a larger number of excised reactive benign cervical lymph nodes. Whether this association indicates a protective role of thyroid autoimmunity in lymph node spreading remains unclear. CCND = central compartment node dissection DTC = differentiated thyroid cancer HT = Hashimoto thyroiditis LT = lymphocytic thyroiditis TgAb = thyroglobulin antibody TPO = thyroid peroxidase.

  20. A novel method for producing target cells and assessing cytotoxic T lymphocyte activity in outbred hosts

    Directory of Open Access Journals (Sweden)

    Bendinelli Mauro

    2009-03-01

    Full Text Available Abstract Background Cytotoxic T lymphocytes play a crucial role in the immunological control of microbial infections and in the design of vaccines and immunotherapies. Measurement of cytotoxic T lymphocyte activity requires that the test antigen is presented by target cells having the same or compatible class I major hystocompatibility complex antigens as the effector cells. Conventional assays use target cells labeled with 51chromium and infer cytotoxic T lymphocyte activity by measuring the isotope released by the target cells lysed following incubation with antigen-specific cytotoxic T lymphocytes. This assay is sensitive but needs manipulation and disposal of hazardous radioactive reagents and provides a bulk estimate of the reporter released, which may be influenced by spontaneous release of the label and other poorly controllable variables. Here we describe a novel method for producing target in outbred hosts and assessing cytotoxic T lymphocyte activity by flow cytometry. Results The method consists of culturing skin fibroblasts, immortalizing them with a replication defective clone of simian virus 40, and finally transducing them with a bicistronic vector encoding the target antigen and the reporter green fluorescent protein. When used in a flow cytometry-based assay, the target cells obtained with this method proved valuable for assessing the viral envelope protein specific cytotoxic T lymphocyte activity in domestic cats acutely or chronically infected with feline immunodeficiency virus, a lentivirus similar to human immunodeficiency virus and used as animal model for AIDS studies. Conclusion Given the versatility of the bicistronic vector used, its ability to deliver multiple and large transgenes in target cells, and its extremely wide cell specificity when pseudotyped with the vesicular stomatitis virus envelope protein, the method is potentially exploitable in many animal species.

  1. Tissue specific heterogeneity in effector immune cell response

    Directory of Open Access Journals (Sweden)

    Saba eTufail

    2013-08-01

    Full Text Available Post pathogen invasion, migration of effector T-cell subsets to specific tissue locations is of prime importance for generation of robust immune response. Effector T cells are imprinted with distinct ‘homing codes’ (adhesion molecules and chemokine receptors during activation which regulate their targeted trafficking to specific tissues. Internal cues in the lymph node microenvironment along with external stimuli from food (vitamin A and sunlight (vitamin D3 prime dendritic cells, imprinting them to play centrestage in the induction of tissue tropism in effector T cells. B cells as well, in a manner similar to effector T cells, exhibit tissue tropic migration. In this review, we have focused on the factors regulating the generation and migration of effector T cells to various tissues alongwith giving an overview of tissue tropism in B cells.

  2. Differentiation of B and T lymphocytes from precursor cells resident in the bone marrow

    Energy Technology Data Exchange (ETDEWEB)

    Rosse, C; Press, O W

    1978-01-01

    A series of experiments in guinea pigs and mice established that proliferating progenitor cells for B and T lymphocytes are a resident population in the bone marrow. It was shown by the combined use of /sup 3/H-TdR radioautography and fluorescent-antibody staining of B and T cells that the majority of bone marrow (BM) lymphocytes are rapidly renewed (RR) B cells and null cells, whereas the thymus (THY) consists overwhelming of RR T lymphocytes; in spleen (SPL) and lymph node (LN) slowly renewed (SR) T and B cells predominate. The rate of B cell turnover in guinea pig bone marrow exceeds that in the SPL or LN, and the appearance of newly generated B cells in the SPL lags behind that in the BM. When systematically administered /sup 3/H-TdR was excluded by tourniquets from tibial and femoral BM no labeled B cells appeared in tibial or femoral marrow over 72 h. When tibial and femoral BM was labeled selectively with /sup 3/H-TdR, labeled B cells appeared in the SPL and LN over 72 h. (It was found in CBA mice that BM cell fractions enriched in lymphocytes (BML) responded to the T cell mitogen PHA in a manner qualitatively different from the response of SPL and LN cells. Experiments with athymic nude mice and with complement-mediated lysis of T and B cells established that PHA responsive cells in SPL and LN were T cells but in BML they were null lymphocytes. Target cells of PHA in BML responded to the mitogen by the generation of T-cell surface markers and blastogenesis; therefore they were identified as pre-T cells. BM pre-T cells are rapidly renewed and, in contrast to PHA responsive cells of SPL and LN, do not recirculate from blood to lymph. Both B and pre-T cells in the BM are division products of transitional cells. Among transitional cells of the marrow are included the progenitors of B and T lmyphhocytes and of all other types of hemopoietic cells.

  3. Expression patterns of signaling lymphocytic activation molecule family members in peripheral blood mononuclear cell subsets in patients with systemic lupus erythematosus.

    Science.gov (United States)

    Karampetsou, Maria P; Comte, Denis; Kis-Toth, Katalin; Kyttaris, Vasileios C; Tsokos, George C

    2017-01-01

    Genome-wide linkage analysis studies (GWAS) studies in systemic lupus erythematosus (SLE) identified the 1q23 region on human chromosome 1, containing the Signaling Lymphocytic Activation Molecule Family (SLAMF) cluster of genes, as a lupus susceptibility locus. The SLAMF molecules (SLAMF1-7) are immunoregulatory receptors expressed predominantly on hematopoietic cells. Activation of cells of the adaptive immune system is aberrant in SLE and dysregulated expression of certain SLAMF molecules has been reported. We examined the expression of SLAMF1-7 on peripheral blood T cells, B cells, monocytes, and their respective differentiated subsets, in patients with SLE and healthy controls in a systematic manner. SLAMF1 levels were increased on both T cell and B cells and their differentiated subpopulations in patients with SLE. SLAMF2 was increased on SLE CD4+ and CD8+ T cells. The frequency of SLAMF4+ and SLAMF7+ central memory and effector memory CD8+ T cells was reduced in SLE patients. Naïve CD4+ and CD8+ SLE T cells showed a slight increase in SLAMF3 levels. No differences were seen in the expression of SLAMF5 and SLAMF6 among SLE patients and healthy controls. Overall, the expression of various SLAMF receptors is dysregulated in SLE and may contribute to the immunopathogenesis of the disease.

  4. CD4+ lymphocytes control gut epithelial apoptosis and mediate survival in sepsis.

    Science.gov (United States)

    Stromberg, Paul E; Woolsey, Cheryl A; Clark, Andrew T; Clark, Jessica A; Turnbull, Isaiah R; McConnell, Kevin W; Chang, Katherine C; Chung, Chun-Shiang; Ayala, Alfred; Buchman, Timothy G; Hotchkiss, Richard S; Coopersmith, Craig M

    2009-06-01

    Lymphocytes help determine whether gut epithelial cells proliferate or differentiate but are not known to affect whether they live or die. Here, we report that lymphocytes play a controlling role in mediating gut epithelial apoptosis in sepsis but not under basal conditions. Gut epithelial apoptosis is similar in unmanipulated Rag-1(-/-) and wild-type (WT) mice. However, Rag-1(-/-) animals have a 5-fold augmentation in gut epithelial apoptosis following cecal ligation and puncture (CLP) compared to septic WT mice. Reconstitution of lymphocytes in Rag-1(-/-) mice via adoptive transfer decreases intestinal apoptosis to levels seen in WT animals. Subset analysis indicates that CD4(+) but not CD8(+), gammadelta, or B cells are responsible for the antiapoptotic effect of lymphocytes on the gut epithelium. Gut-specific overexpression of Bcl-2 in transgenic mice decreases mortality following CLP. This survival benefit is lymphocyte dependent since gut-specific overexpression of Bcl-2 fails to alter survival when the transgene is overexpressed in Rag-1(-/-) mice. Further, adoptively transferring lymphocytes to Rag-1(-/-) mice that simultaneously overexpress gut-specific Bcl-2 results in improved mortality following sepsis. Thus, sepsis unmasks CD4(+) lymphocyte control of gut apoptosis that is not present under homeostatic conditions, which acts as a key determinant of both cellular survival and host mortality.

  5. Tumor rejection induced by CD70-mediated quantitative and qualitative effects on effector CD8+ T cell formation

    NARCIS (Netherlands)

    Arens, Ramon; Schepers, Koen; Nolte, Martijn A.; van Oosterwijk, Michiel F.; van Lier, René A. W.; Schumacher, Ton N. M.; van Oers, Marinus H. J.

    2004-01-01

    In vivo priming of antigen-specific CD8+ T cells results in their expansion and differentiation into effector T cells followed by contraction into a memory T cell population that can be maintained for life. Recent evidence suggests that after initial antigenic stimulation, the magnitude and kinetics

  6. Special-purpose multifingered robotic end-effectors

    International Nuclear Information System (INIS)

    Crowder, R.M.

    1990-01-01

    A number of advanced multifingered robotic end-effectors have been developed recently in which the finger joints are powered from external actuators. Although this gives dexterous performance, there are considerable problems with power transmission, due to the use of flexible tendons between the external actuators and the individual finger joints. If a multifingered robotic end-effector is to be operated in a confined space, local actuation of the fingers needs to be fully considered, even if there is a reduction in hand dexterity over that of an externally mounted actuator system. The University of Southampton has developed a number of end-effectors that incorporate integral finger actuators and mechanisms, two examples of which are discussed in this paper

  7. HIV-1 infection and first line ART induced differential responses in mitochondria from blood lymphocytes and monocytes: the ANRS EP45 "Aging" study.

    Directory of Open Access Journals (Sweden)

    Sophie Perrin

    Full Text Available The ANRS EP45 "Aging" study investigates the cellular mechanisms involved in the accelerated aging of HIV-1 infected and treated patients. The data reported focus on mitochondria, organelles known to be involved in cell senescence.49 HIV-1 infected patients untreated with antiretroviral therapy, together with 49 seronegative age- and sex-matched control subjects and 81 HIV-1 infected and treated patients, were recruited by 3 AIDS centres (Marseille, Montpellier, Nice; France; http://clinicaltrials.gov/, NCT01038999. In more than 88% of treated patients, the viral load was 500/mm(3. ROS (reactive oxygen species production and ΔΨm (inner membrane potential were measured by flow cytometry in blood lymphocytes and monocytes (functional parameters. Three mitochondrial network quantitative morphological parameters were computed using confocal microscopy and image analysis. Three PBMC mitochondrial proteins (porin and subunits 2 and 4 of cytochrome C oxidase encoded by mtDNA or nuclear DNA, respectively were analysed by western blotting.Quantitative changes in PBMC mitochondrial proteins were not induced by either HIV-1 infection or ART. Discriminant analysis integrating functional (ROS production and ΔΨm or morphological (network volume density, fragmentation and branching parameters revealed HIV-1 infection and ART differential effects according to cell type. First line ART tended to rescue lymphocyte mitochondrial parameters altered by viral infection, but induced slight changes in monocytes. No statistical difference was found between the effects of three ART regimens on mitochondrial parameters. Correlations between functional parameters and viral load confirmed the damaging effects of HIV-1 in lymphocyte mitochondria.In patients considered to be clinically stable, mitochondria exhibited functional and morphological modifications in PBMCs resulting from either direct or indirect effects of HIV-1 infection (lymphocytes, or from first line ART

  8. RNAi effector diversity in nematodes.

    Directory of Open Access Journals (Sweden)

    Johnathan J Dalzell

    2011-06-01

    Full Text Available While RNA interference (RNAi has been deployed to facilitate gene function studies in diverse helminths, parasitic nematodes appear variably susceptible. To test if this is due to inter-species differences in RNAi effector complements, we performed a primary sequence similarity survey for orthologs of 77 Caenorhabditis elegans RNAi pathway proteins in 13 nematode species for which genomic or transcriptomic datasets were available, with all outputs subjected to domain-structure verification. Our dataset spanned transcriptomes of Ancylostoma caninum and Oesophagostomum dentatum, and genomes of Trichinella spiralis, Ascaris suum, Brugia malayi, Haemonchus contortus, Meloidogyne hapla, Meloidogyne incognita and Pristionchus pacificus, as well as the Caenorhabditis species C. brenneri, C. briggsae, C. japonica and C. remanei, and revealed that: (i Most of the C. elegans proteins responsible for uptake and spread of exogenously applied double stranded (dsRNA are absent from parasitic species, including RNAi-competent plant-nematodes; (ii The Argonautes (AGOs responsible for gene expression regulation in C. elegans are broadly conserved, unlike those recruited during the induction of RNAi by exogenous dsRNA; (iii Secondary Argonautes (SAGOs are poorly conserved, and the nuclear AGO NRDE-3 was not identified in any parasite; (iv All five Caenorhabditis spp. possess an expanded RNAi effector repertoire relative to the parasitic nematodes, consistent with the propensity for gene loss in nematode parasites; (v In spite of the quantitative differences in RNAi effector complements across nematode species, all displayed qualitatively similar coverage of functional protein groups. In summary, we could not identify RNAi effector deficiencies that associate with reduced susceptibility in parasitic nematodes. Indeed, similarities in the RNAi effector complements of RNAi refractory and competent nematode parasites support the broad applicability of this research

  9. Chronic Alcohol Ingestion Delays T Cell Activation and Effector Function in Sepsis.

    Directory of Open Access Journals (Sweden)

    Lindsay M Margoles

    Full Text Available Sepsis is the leading cause of death in intensive care units in the US, and it is known that chronic alcohol use is associated with higher incidence of sepsis, longer ICU stays, and higher mortality from sepsis. Both sepsis and chronic alcohol use are associated with immune deficits such as decreased lymphocyte numbers, impaired innate immunity, delayed-type hypersensitivity reactions, and susceptibility to infections; however, understanding of specific pathways of interaction or synergy between these two states of immune dysregulation is lacking. This study therefore sought to elucidate mechanisms underlying the immune dysregulation observed during sepsis in the setting of chronic alcohol exposure. Using a murine model of chronic ethanol ingestion followed by sepsis induction via cecal ligation and puncture, we determined that while CD4+ and CD8+ T cells isolated from alcohol fed mice eventually expressed the same cellular activation markers (CD44, CD69, and CD43 and effector molecules (IFN-γ, TNF as their water fed counterparts, there was an overall delay in the acquisition of these phenotypes. This early lag in T cell activation was associated with significantly reduced IL-2 production at a later timepoint in both the CD4+ and CD8+ T cell compartments in alcohol sepsis, as well as with a reduced accumulation of CD8dim activated effectors. Taken together, these data suggest that delayed T cell activation may result in qualitative differences in the immune response to sepsis in the setting of chronic alcohol ingestion.

  10. Decreased staging of differentiated thyroid cancer in patients with chronic lymphocytic thyroiditis.

    Science.gov (United States)

    Borowczyk, M; Janicki, A; Dworacki, G; Szczepanek-Parulska, E; Danieluk, M; Barnett, J; Antonik, M; Kałużna, M; Bromińska, B; Czepczyński, R; Bączyk, M; Ziemnicka, K; Ruchała, M

    2018-04-04

    The biological association between chronic lymphocytic thyroiditis (CLT) and differentiated thyroid cancer (DTC) has not been elucidated yet. The aim of the study was to assess whether the presence of CLT exerts any influence on clinical or histological presentation of DTC. Nine hundred and seven consecutive patients with DTC treated in the years 1998-2016 were divided into two groups according to the presence or absence of concomitant CLT. The statistical differences were analysed. Out of 907 patients included in the study, 331 were diagnosed with DTC and CLT (studied group), while 576 patients with DTC but without CLT constituted a control group. The distribution of papillary and follicular thyroid cancer did not differ. In CLT group, the prevalence of pT1 was greater than for pT2-pT4 DTC (P = 0.0003; OR = 1.69, 95% CI 1.27-2.24) compared to controls (68.3 vs. 56.1%, respectively). The presence of multifocal lesions was similar. The thyroid capsule infiltration without extrathyroidal invasion (P CLT (P = 0.004; OR = 1.66; 95% CI 1.17-2.34) as well as nodal involvement (P = 0.048; OR = 0.65, 95% CI 0.42-0.99). The collected data indicate a protective role of CLT in preventing the spread of the DTC. The presence of CLT might limit tumour growth to the primary site.

  11. Xenogeneic graft-versus-host-disease in NOD-scid IL-2Rγnull mice display a T-effector memory phenotype.

    Science.gov (United States)

    Ali, Niwa; Flutter, Barry; Sanchez Rodriguez, Robert; Sharif-Paghaleh, Ehsan; Barber, Linda D; Lombardi, Giovanna; Nestle, Frank O

    2012-01-01

    The occurrence of Graft-versus-Host Disease (GvHD) is a prevalent and potentially lethal complication that develops following hematopoietic stem cell transplantation. Humanized mouse models of xenogeneic-GvHD based upon immunodeficient strains injected with human peripheral blood mononuclear cells (PBMC; "Hu-PBMC mice") are important tools to study human immune function in vivo. The recent introduction of targeted deletions at the interleukin-2 common gamma chain (IL-2Rγ(null)), notably the NOD-scid IL-2Rγ(null) (NSG) and BALB/c-Rag2(null) IL-2Rγ(null) (BRG) mice, has led to improved human cell engraftment. Despite their widespread use, a comprehensive characterisation of engraftment and GvHD development in the Hu-PBMC NSG and BRG models has never been performed in parallel. We compared engrafted human lymphocyte populations in the peripheral blood, spleens, lymph nodes and bone marrow of these mice. Kinetics of engraftment differed between the two strains, in particular a significantly faster expansion of the human CD45(+) compartment and higher engraftment levels of CD3(+) T-cells were observed in NSG mice, which may explain the faster rate of GvHD development in this model. The pathogenesis of human GvHD involves anti-host effector cell reactivity and cutaneous tissue infiltration. Despite this, the presence of T-cell subsets and tissue homing markers has only recently been characterised in the peripheral blood of patients and has never been properly defined in Hu-PBMC models of GvHD. Engrafted human cells in NSG mice shows a prevalence of tissue homing cells with a T-effector memory (T(EM)) phenotype and high levels of cutaneous lymphocyte antigen (CLA) expression. Characterization of Hu-PBMC mice provides a strong preclinical platform for the application of novel immunotherapies targeting T(EM)-cell driven GvHD.

  12. Xenogeneic graft-versus-host-disease in NOD-scid IL-2Rγnull mice display a T-effector memory phenotype.

    Directory of Open Access Journals (Sweden)

    Niwa Ali

    Full Text Available The occurrence of Graft-versus-Host Disease (GvHD is a prevalent and potentially lethal complication that develops following hematopoietic stem cell transplantation. Humanized mouse models of xenogeneic-GvHD based upon immunodeficient strains injected with human peripheral blood mononuclear cells (PBMC; "Hu-PBMC mice" are important tools to study human immune function in vivo. The recent introduction of targeted deletions at the interleukin-2 common gamma chain (IL-2Rγ(null, notably the NOD-scid IL-2Rγ(null (NSG and BALB/c-Rag2(null IL-2Rγ(null (BRG mice, has led to improved human cell engraftment. Despite their widespread use, a comprehensive characterisation of engraftment and GvHD development in the Hu-PBMC NSG and BRG models has never been performed in parallel. We compared engrafted human lymphocyte populations in the peripheral blood, spleens, lymph nodes and bone marrow of these mice. Kinetics of engraftment differed between the two strains, in particular a significantly faster expansion of the human CD45(+ compartment and higher engraftment levels of CD3(+ T-cells were observed in NSG mice, which may explain the faster rate of GvHD development in this model. The pathogenesis of human GvHD involves anti-host effector cell reactivity and cutaneous tissue infiltration. Despite this, the presence of T-cell subsets and tissue homing markers has only recently been characterised in the peripheral blood of patients and has never been properly defined in Hu-PBMC models of GvHD. Engrafted human cells in NSG mice shows a prevalence of tissue homing cells with a T-effector memory (T(EM phenotype and high levels of cutaneous lymphocyte antigen (CLA expression. Characterization of Hu-PBMC mice provides a strong preclinical platform for the application of novel immunotherapies targeting T(EM-cell driven GvHD.

  13. Robotic end-effector for rewaterproofing shuttle tiles

    Science.gov (United States)

    Manouchehri, Davoud; Hansen, Joseph M.; Wu, Cheng M.; Yamamoto, Brian S.; Graham, Todd

    1992-11-01

    This paper summarizes work by Rockwell International's Space Systems Division's Robotics Group at Downey, California. The work is part of a NASA-led team effort to automate Space Shuttle rewaterproofing in the Orbiter Processing Facility at the Kennedy Space Center and the ferry facility at the Ames-Dryden Flight Research Facility. Rockwell's effort focuses on the rewaterproofing end-effector, whose function is to inject hazardous dimethylethyloxysilane into thousands of ceramic tiles on the underside of the orbiter after each flight. The paper has five sections. First, it presents background on the present manual process. Second, end-effector requirements are presented, including safety and interface control. Third, a design is presented for the five end-effector systems: positioning, delivery, containment, data management, and command and control. Fourth, end-effector testing and integrating to the total system are described. Lastly, future applications for this technology are discussed.

  14. Long-Term Live Cell Imaging Reveals New Roles For Salmonella Effector Proteins SseG and SteA

    Science.gov (United States)

    McQuate, Sarah E.; Young, Alexandra M.; Silva-Herzog, Eugenia; Bunker, Eric; Hernandez, Mateo; de Chaumont, Fabrice; Liu, Xuedong; Detweiler, Corrella S.; Palmer, Amy E.

    2016-01-01

    Summary Salmonella Typhimurium is an intracellular bacterial pathogen that infects both epithelial cells and macrophages. Salmonella effector proteins, which are translocated into the host cell and manipulate host cell components, control the ability to replicate and/or survive in host cells. Due to the complexity and heterogeneity of Salmonella infections, there is growing recognition of the need for single cell and live-cell imaging approaches to identify and characterize the diversity of cellular phenotypes and how they evolve over time. Here we establish a pipeline for long-term (16 hours) live-cell imaging of infected cells and subsequent image analysis methods. We apply this pipeline to track bacterial replication within the Salmonella-containing vacuole in epithelial cells, quantify vacuolar replication versus survival in macrophages, and investigate the role of individual effector proteins in mediating these parameters. This approach revealed that dispersed bacteria can coalesce at later stages of infection, that the effector protein SseG influences the propensity for cytosolic hyperreplication in epithelial cells, and that while SteA only has a subtle effect on vacuolar replication in epithelial cells, it has a profound impact on infection parameters in immunocompetent macrophages, suggesting differential roles for effector proteins in different infection models. PMID:27376507

  15. Xianfanghuomingyin, a Chinese Compound Medicine, Modulates the Proliferation and Differentiation of T Lymphocyte in a Collagen-Induced Arthritis Mouse Model

    Directory of Open Access Journals (Sweden)

    Bo Nie

    2016-01-01

    Full Text Available In traditional Chinese medicine (TCM, xianfanghuomingyin (XFHM is used to treat autoimmune diseases, including rheumatoid arthritis (RA. Here, we studied the mechanisms underlying its treatment effects, especially its anti-inflammatory effects in a collagen-induced arthritis (CIA mouse model. We found that cartilage destruction and pannus formation were alleviated by treatment with XFHM. The abnormal differentiation of Th1 and Th17 cells was downregulated significantly by XFHM, and Th2 and Treg cells were upregulated. Moreover, the expression levels of specific cytokines and transcription factors related to Th1 cells (interferon γ [IFNγ], T-bet and Th17 cells (interleukin- [IL-] 17 and the nuclear receptor retinoic acid receptor-related orphan receptor-gamma (RORγ were downregulated. Serum IL-4 and GATA-3, which contribute to Th2 cells differentiation, increased significantly after XFHM administration. These results indicate that XFHM can restore the balance of T lymphocytes and reestablish the immunological tolerance to inhibit autoinflammatory disorder of RA. Taken together, XFHM can be used as a complementary or alternative traditional medicine to treat RA.

  16. The In Vivo Granulopoietic Response to Dexamethasone Injection Is Abolished in Perforin-Deficient Mutant Mice and Corrected by Lymphocyte Transfer from Nonsensitized Wild-Type Donors

    Directory of Open Access Journals (Sweden)

    Pedro Xavier-Elsas

    2015-01-01

    Full Text Available Exogenously administered glucocorticoids enhance eosinophil and neutrophil granulocyte production from murine bone-marrow. A hematological response dependent on endogenous glucocorticoids underlies bone-marrow eosinophilia induced by trauma or allergic sensitization/challenge. We detected a defect in granulopoiesis in nonsensitized, perforin-deficient mice. In steady-state conditions, perforin- (Pfp- deficient mice showed significantly decreased bone-marrow and blood eosinophil and neutrophil counts, and colony formation in response to GM-CSF, relative to wild-type controls of comparable age and/or weight. By contrast, peripheral blood or spleen total cell and lymphocyte numbers were not affected by perforin deficiency. Dexamethasone enhanced colony formation by GM-CSF-stimulated progenitors from wild-type controls, but not Pfp mice. Dexamethasone injection increased bone-marrow eosinophil and neutrophil counts in wild-type controls, but not Pfp mice. Because perforin is expressed in effector lymphocytes, we examined whether this defect would be corrected by transferring wild-type lymphocytes into perforin-deficient recipients. Short-term reconstitution of the response to dexamethasone was separately achieved for eosinophils and neutrophils by transfer of distinct populations of splenic lymphocytes from nonsensitized wild-type donors. Transfer of the same amount of splenic lymphocytes from perforin-deficient donors was ineffective. This demonstrates that the perforin-dependent, granulopoietic response to dexamethasone can be restored by transfer of innate lymphocyte subpopulations.

  17. Mycobacterium tuberculosis effectors interfering host apoptosis signaling.

    Science.gov (United States)

    Liu, Minqiang; Li, Wu; Xiang, Xiaohong; Xie, Jianping

    2015-07-01

    Tuberculosis remains a serious human public health concern. The coevolution between its pathogen Mycobacterium tuberculosis and human host complicated the way to prevent and cure TB. Apoptosis plays subtle role in this interaction. The pathogen endeavors to manipulate the apoptosis via diverse effectors targeting key signaling nodes. In this paper, we summarized the effectors pathogen used to subvert the apoptosis, such as LpqH, ESAT-6/CFP-10, LAMs. The interplay between different forms of cell deaths, such as apoptosis, autophagy, necrosis, is also discussed with a focus on the modes of action of effectors, and implications for better TB control.

  18. Epigenetic control of effectors in plant pathogens

    Directory of Open Access Journals (Sweden)

    Mark eGijzen

    2014-11-01

    Full Text Available Plant pathogens display impressive versatility in adapting to host immune systems. Pathogen effector proteins facilitate disease but can become avirulence (Avr factors when the host acquires discrete recognition capabilities that trigger immunity. The mechanisms that lead to changes to pathogen Avr factors that enable escape from host immunity are diverse, and include epigenetic switches that allow for reuse or recycling of effectors. This perspective outlines possibilities of how epigenetic control of Avr effector gene expression may have arisen and persisted in plant pathogens, and how it presents special problems for diagnosis and detection of specific pathogen strains or pathotypes.

  19. Lymphocytic infundibulo-neurohypophysitis (LINH) with involvement of the hypothalamus and with coexistent focal infiltration of the brain stem: A case report

    International Nuclear Information System (INIS)

    Spalek, M.; Kowalska, A.

    2006-01-01

    Autoimmune (lymphocytic) hypophysitis is a rare disease. It was originally labeled lymphocytic adenohypophysitis (LAH) and was first described in 1962. However, when it was later realized that the autoimmune infiltrate could exclusively involve the infundibular stem and the posterior lobe, the term lymphocytic infundibulo-neurohypophysitis (LINH) was created. Review of the literature identified 39 patients with LINH, 245 with LAH, and 95 with LPH (lymphocytic pan-hypophysitis) to date. The authors present the case of a 19-year-old woman with acute bacterial infection previous to symptoms of hypopituitarism. CT and MR imaging showed tumor-like areas of intensive post-contrast enhancement without edema in the suprasellar region and in the brain stem. Based on the diagnostic investigations, LINH was diagnosed. Germinoma, sarcoidosis, tuberculosis, and bacterial hypophysitis were excluded in the diagnostic differentiation. Regression of clinical and radiological symptoms was observed after corticotherapy. Lymphocytic infundibulo-neurohypophysitis is a rare disease that should be considered in the differential diagnosis of any suprasellar and/or intrasellar mass. (author)

  20. TAL effectors and the executor R genes.

    Science.gov (United States)

    Zhang, Junli; Yin, Zhongchao; White, Frank

    2015-01-01

    Transcription activator-like (TAL) effectors are bacterial type III secretion proteins that function as transcription factors in plants during Xanthomonas/plant interactions, conditioning either host susceptibility and/or host resistance. Three types of TAL effector associated resistance (R) genes have been characterized-recessive, dominant non-transcriptional, and dominant TAL effector-dependent transcriptional based resistance. Here, we discuss the last type of R genes, whose functions are dependent on direct TAL effector binding to discrete effector binding elements in the promoters. Only five of the so-called executor R genes have been cloned, and commonalities are not clear. We have placed the protein products in two groups for conceptual purposes. Group 1 consists solely of the protein from pepper, BS3, which is predicted to have catalytic function on the basis of homology to a large conserved protein family. Group 2 consists of BS4C-R, XA27, XA10, and XA23, all of which are relatively short proteins from pepper or rice with multiple potential transmembrane domains. Group 2 members have low sequence similarity to proteins of unknown function in closely related species. Firm predictions await further experimentation on these interesting new members to the R gene repertoire, which have potential broad application in new strategies for disease resistance.

  1. TAL effectors and the executor R genes

    Directory of Open Access Journals (Sweden)

    Junli eZhang

    2015-08-01

    Full Text Available Transcription activation-like (TAL effectors are bacterial type III secretion proteins that function as transcription factors in plants during Xanthomonas/plant interactions, conditioning either host susceptibility and/or host resistance. Three types of TAL effector associated resistance (R genes have been characterized - recessive, dominant non-transcriptional and dominant TAL effector-dependent transcriptional based resistance. Here, we discuss the last type of R genes, whose functions are dependent on direct TAL effector binding to discrete effector binding elements in the promoters. Only five of the so-called executor R genes have been cloned, and commonalities are not clear. We have placed the protein products in two groups for conceptual purposes. Group 1 consists solely of the protein from pepper, BS3, which is predicted to have catalytic function on the basis of homology to a large conserved protein family. Group 2 consists of BS4C-R, XA27, XA10, and XA23, all of which are relatively short proteins from pepper or rice with multiple potential transmembrane domains. Group 2 members have low sequence similarity to proteins of unknown function in closely related species. Firm predictions await further experimentation on these interesting new members to the R gene repertoire, which have potential broad application in new strategies for disease resistance.

  2. Genome-scale identification of Legionella pneumophila effectors using a machine learning approach.

    Directory of Open Access Journals (Sweden)

    David Burstein

    2009-07-01

    Full Text Available A large number of highly pathogenic bacteria utilize secretion systems to translocate effector proteins into host cells. Using these effectors, the bacteria subvert host cell processes during infection. Legionella pneumophila translocates effectors via the Icm/Dot type-IV secretion system and to date, approximately 100 effectors have been identified by various experimental and computational techniques. Effector identification is a critical first step towards the understanding of the pathogenesis system in L. pneumophila as well as in other bacterial pathogens. Here, we formulate the task of effector identification as a classification problem: each L. pneumophila open reading frame (ORF was classified as either effector or not. We computationally defined a set of features that best distinguish effectors from non-effectors. These features cover a wide range of characteristics including taxonomical dispersion, regulatory data, genomic organization, similarity to eukaryotic proteomes and more. Machine learning algorithms utilizing these features were then applied to classify all the ORFs within the L. pneumophila genome. Using this approach we were able to predict and experimentally validate 40 new effectors, reaching a success rate of above 90%. Increasing the number of validated effectors to around 140, we were able to gain novel insights into their characteristics. Effectors were found to have low G+C content, supporting the hypothesis that a large number of effectors originate via horizontal gene transfer, probably from their protozoan host. In addition, effectors were found to cluster in specific genomic regions. Finally, we were able to provide a novel description of the C-terminal translocation signal required for effector translocation by the Icm/Dot secretion system. To conclude, we have discovered 40 novel L. pneumophila effectors, predicted over a hundred additional highly probable effectors, and shown the applicability of machine

  3. Phytohemagglutinin (PHA) stimulation of peripheral-blood lymphocytes and stem cell take

    Energy Technology Data Exchange (ETDEWEB)

    Astaldi, G [Blood Research Foundation Center, Tortona, Italy; Karanovic, D; Vettori, P P; Karanovic, J; Piletic, O

    1974-01-01

    The effect of PHA-stimulation of peripheral-blood lymphocytes on the spleen-colony formation in irradiated rats was examined. 25-day old Wistar rats underwent total-body irradiation (600 R), and they were used as recipients. On the other hand, 2 and /sup 1///sub 2/ month old untreated Wistar rats were used as donors of peripheral-blood lymphocytes, which were obtained by sedimentation with Dextraven from defibrinated blood. Four rat lots were used. The 1st one did not receive irradiation, and was kept as ''blank control.'' The 2nd one was just irradiated and kept as ''radiated control.'' The 3rd and the 4th rat lots of the series were irradiated, but the former lot was injected i.v. with 5 x 10/sup 7/ peripheral-blood untreated lymphocytes, whereas the fourth lot was injected i.v. with the same amount of lymphocytes, which were previously incubated in vitro for 24 hrs with PHA-M (Difco). The results showed that the PHA-incubation of transplanted peripheral-blood lymphocytes significantly increases the number and size of the macroscopic spleen colonies, in relationship to the colonies which occurs after transplantation of untreated lymphocytes. Histo-cytological observation clearly showed that the colonies formed after injection of mitogen-pretreated peripheral-blood lymphocytes were predominantly of erythroid type and, then, of non-differentiated cells. Only a few of them were of a mixed type, consisting of both undifferentiated cells and erythroid cells.

  4. Expression of blood serum proteins and lymphocyte differentiation clusters after chronic occupational exposure to ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Rybkina, Valentina L.; Azizova, Tamara V.; Adamova, Galina V.; Teplyakova, Olga V.; Osovets, Sergey V.; Bannikova, Maria V. [Southern Urals Biophysics Institute, Ozyorsk, Chelyabinsk Region (Russian Federation); Scherthan, Harry; Meineke, Viktor; Doerr, Harald [University of Ulm, Bundeswehr Institute of Radiobiology, Munich (Germany); Zurochka, Alexander V. [Immunology Institute, Yekaterinburg (Russian Federation)

    2014-11-15

    This study aimed to assess effects of chronic occupational exposure on immune status in Mayak workers chronically exposed to ionizing radiation (IR). The study cohort consists of 77 workers occupationally exposed to external gamma-rays at total dose from 0.5 to 3.0 Gy (14 individuals) and workers with combined exposure (external gamma-rays at total dose range 0.7-5.1 Gy and internal alpha-radiation from incorporated plutonium with a body burden of 0.3-16.4 kBq). The control group consists of 43 age- and sex-matched individuals who never were exposed to IR, never involved in any cleanup operations following radiation accidents and never resided at contaminated areas. Enzyme-linked immunoassay and flow cytometry were used to determine the relative concentration of lymphocytes and proteins. The concentrations of T-lymphocytes, interleukin-8 and immunoglobulins G were decreased in external gamma-exposed workers relative to control. Relative concentrations of NKT-lymphocytes, concentrations of transforming growth factor-β, interferon gamma, immunoglobulins A, immunoglobulins M and matrix proteinase-9 were higher in this group as compared with control. Relative concentrations of T-lymphocytes and concentration of interleukin-8 were decreased, while both the relative and absolute concentration of natural killers, concentration of immunoglobulins A and M and matrix proteinase-9 were increased in workers with combined exposure as compared to control. An inverse linear relation was revealed between absolute concentration of T-lymphocytes, relative and absolute concentration of T-helpers cells, concentration of interferon gamma and total absorbed dose from external gamma-rays in exposed workers. For workers with incorporated plutonium, there was an inverse linear relation of absolute concentration of T-helpers as well as direct linear relation of relative concentration of NKT-lymphocytes to total absorbed red bone marrow dose from internal alpha-radiation. In all, chronic

  5. Expression of blood serum proteins and lymphocyte differentiation clusters after chronic occupational exposure to ionizing radiation

    International Nuclear Information System (INIS)

    Rybkina, Valentina L.; Azizova, Tamara V.; Adamova, Galina V.; Teplyakova, Olga V.; Osovets, Sergey V.; Bannikova, Maria V.; Scherthan, Harry; Meineke, Viktor; Doerr, Harald; Zurochka, Alexander V.

    2014-01-01

    This study aimed to assess effects of chronic occupational exposure on immune status in Mayak workers chronically exposed to ionizing radiation (IR). The study cohort consists of 77 workers occupationally exposed to external gamma-rays at total dose from 0.5 to 3.0 Gy (14 individuals) and workers with combined exposure (external gamma-rays at total dose range 0.7-5.1 Gy and internal alpha-radiation from incorporated plutonium with a body burden of 0.3-16.4 kBq). The control group consists of 43 age- and sex-matched individuals who never were exposed to IR, never involved in any cleanup operations following radiation accidents and never resided at contaminated areas. Enzyme-linked immunoassay and flow cytometry were used to determine the relative concentration of lymphocytes and proteins. The concentrations of T-lymphocytes, interleukin-8 and immunoglobulins G were decreased in external gamma-exposed workers relative to control. Relative concentrations of NKT-lymphocytes, concentrations of transforming growth factor-β, interferon gamma, immunoglobulins A, immunoglobulins M and matrix proteinase-9 were higher in this group as compared with control. Relative concentrations of T-lymphocytes and concentration of interleukin-8 were decreased, while both the relative and absolute concentration of natural killers, concentration of immunoglobulins A and M and matrix proteinase-9 were increased in workers with combined exposure as compared to control. An inverse linear relation was revealed between absolute concentration of T-lymphocytes, relative and absolute concentration of T-helpers cells, concentration of interferon gamma and total absorbed dose from external gamma-rays in exposed workers. For workers with incorporated plutonium, there was an inverse linear relation of absolute concentration of T-helpers as well as direct linear relation of relative concentration of NKT-lymphocytes to total absorbed red bone marrow dose from internal alpha-radiation. In all, chronic

  6. Bovine ocular squamous cell carcinoma: UV sensitivity in lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Lavin, M.F.; Jennings, P.A.; Hughes, D.J. (Queensland Univ., Brisbane (Australia))

    1982-05-01

    Increased sensitivity to UV light has been demonstrated in Phytohaemagglutinin stimulated lymphocytes from normal and tumour-bearing Hereford cattle when compared to lymphocytes from other breeds. Trypan blue exclusion and inhibition of DNA synthesis were used to determine cell viability. The results obtained from time course and radiation dose experiments demonstrate biphasic survival kinetics. This is indicative of at least two separate cell populations, exhibiting differential sensitivity to UV. The increased sensitivity to UV observed in Herefords may reflect a general sensitivity to UV or alternatively a different cellular constitution in the mitogen stimulated cultures. DNA repair synthesis, measured in the presence of hydroxyurea, was of similar levels in cell cultures from Herefords and one of the control breeds.

  7. Short-term effects of regional irradiation on lymphocytes, T lymphocytes and eosinophils

    International Nuclear Information System (INIS)

    Chazarin, C.; Roche, H.; Bugat, R.; Pris, F.

    1983-01-01

    Twenty-three cancer patients treated only by regional irradiation were studied. Radiotherapy was delivered to the pelvis in 14 patients and to the mediastinum in 9. T lymphocytes were evaluated with the Jondal technique. Before treatment, lymphocyte counts were identical in patients and control. Decreases in total lymphocytes and T lymphocytes became significant in both groups after 40 Gy. Significant rises in eosinophil counts were found only after abdominal irradiation and seemed unrelated to variations in lymphocyte counts [fr

  8. Immunological tolerance to lymphocytic choriomeningitis virus in neonatally infected virus carrier mice: evidence supporting a clonal inactivation mechanism

    International Nuclear Information System (INIS)

    Cihak, J.; Lehmann-Grube, F.

    1978-01-01

    Experiments are described aimed at analysing the mechanism responsible for the absence of cell-mediated immunity against LCM virus-infected cells in neonatally established LCM virus carrier mice. Virus-specific cell-mediated immunity was assessed by 51 Cr release and target cell reduction assays. Attempts to demonstrate cells in spleens of CBA/J carrier mice able to suppress in syngeneic recipients the induction or the effector phase of the cytotoxic T-cell response against LCM virus-infected cells were unsuccessful. Also, no factors were detected in CBA/J and C57BL/6J carrier mice, either spleen cell-associated or free in the circulation, which would block the activity of cytotoxic T-lymphocytes against LCM virus-infected syngeneic target cells. The results indicate that inability of LCM virus carrier mice to act immunologically against virus-infected target cells is due to deletion or irreversible inactivation of T lymphocytes carrying receptors for virally altered cell membrane antigens. (author)

  9. Separate Developmental Programs for HLA-A and -B Cell Surface Expression during Differentiation from Embryonic Stem Cells to Lymphocytes, Adipocytes and Osteoblasts

    DEFF Research Database (Denmark)

    Sabir, Hardee J; Nehlin, Jan O; Qanie, Diyako

    2013-01-01

    -A, but not -B) is seen on some multipotent stem cells, and this raises the question how this is in other stem cells and how it changes during differentiation. In this study, we have used flow cytometry to investigate the cell surface expression of HLA-A and -B on human embryonic stem cells (hESC), human...... hematopoietic stem cells (hHSC), human mesenchymal stem cells (hMSC) and their fully-differentiated progenies such as lymphocytes, adipocytes and osteoblasts. hESC showed extremely low levels of HLA-A and no -B. In contrast, multipotent hMSC and hHSC generally expressed higher levels of HLA-A and clearly HLA......A major problem of allogeneic stem cell therapy is immunologically mediated graft rejection. HLA class I A, B, and Cw antigens are crucial factors, but little is known of their respective expression on stem cells and their progenies. We have recently shown that locus-specific expression (HLA...

  10. Expansion of PD-1-positive effector CD4 T cells in an experimental model of SLE: contribution to the self-organized criticality theory.

    Science.gov (United States)

    Miyazaki, Yumi; Tsumiyama, Ken; Yamane, Takashi; Ito, Mitsuhiro; Shiozawa, Shunichi

    2013-04-18

    We have developed a systems biology concept to explain the origin of systemic autoimmunity. From our studies of systemic lupus erythematosus (SLE) we have concluded that this disease is the inevitable consequence of over-stimulating the host's immune system by repeated exposure to antigen to levels that surpass a critical threshold, which we term the system's "self-organized criticality". We observed that overstimulation of CD4 T cells in mice led to the development of autoantibody-inducing CD4 T cells (aiCD4 T) capable of generating various autoantibodies and pathological lesions identical to those observed in SLE. We show here that this is accompanied by the significant expansion of a novel population of effector T cells characterized by expression of programmed death-1 (PD-1)-positive, CD27(low), CD127(low), CCR7(low) and CD44(high)CD62L(low) markers, as well as increased production of IL-2 and IL-6. In addition, repeated immunization caused the expansion of CD8 T cells into fully-matured cytotoxic T lymphocytes (CTL) that express Ly6C(high)CD122(high) effector and memory markers. Thus, overstimulation with antigen leads to the expansion of a novel effector CD4 T cell population that expresses an unusual memory marker, PD-1, and that may contribute to the pathogenesis of SLE.

  11. Effectors from Wheat Rust Fungi Suppress Multiple Plant Defense Responses.

    Science.gov (United States)

    Ramachandran, Sowmya R; Yin, Chuntao; Kud, Joanna; Tanaka, Kiwamu; Mahoney, Aaron K; Xiao, Fangming; Hulbert, Scot H

    2017-01-01

    Fungi that cause cereal rust diseases (genus Puccinia) are important pathogens of wheat globally. Upon infection, the fungus secretes a number of effector proteins. Although a large repository of putative effectors has been predicted using bioinformatic pipelines, the lack of available high-throughput effector screening systems has limited functional studies on these proteins. In this study, we mined the available transcriptomes of Puccinia graminis and P. striiformis to look for potential effectors that suppress host hypersensitive response (HR). Twenty small (wheat, confirming its activity in a homologous system. Overall, this study provides the first evidence for the presence of effectors in Puccinia species suppressing multiple plant defense responses.

  12. Phytohemagglutinin (PHA) stimulation of peripheral-blood lymphocytes and stem cell take

    Energy Technology Data Exchange (ETDEWEB)

    Astaldi, G. (Blood Research Foundation Center, Tortona, Italy); Karanovic, D.; Vettori, P.P.; Karanovic, J.; Piletic, O.

    1974-01-01

    The effect of PHA-stimulation of peripheral-blood lymphocytes on the spleen-colony formation in irradiated rats was examined. 25-day old Wistar rats underwent total-body irradiation (600 R), and they were used as recipients. On the other hand, 2 and /sup 1///sub 2/ month old untreated Wistar rats were used as donors of peripheral-blood lymphocytes, which were obtained by sedimentation with Dextraven from defibrinated blood. Four rat lots were used. The 1st one did not receive irradiation, and was kept as ''blank control.'' The 2nd one was just irradiated and kept as ''radiated control.'' The 3rd and the 4th rat lots of the series were irradiated, but the former lot was injected i.v. with 5 x 10/sup 7/ peripheral-blood untreated lymphocytes, whereas the fourth lot was injected i.v. with the same amount of lymphocytes, which were previously incubated in vitro for 24 hrs with PHA-M (Difco). The results showed that the PHA-incubation of transplanted peripheral-blood lymphocytes significantly increases the number and size of the macroscopic spleen colonies, in relationship to the colonies which occurs after transplantation of untreated lymphocytes. Histo-cytological observation clearly showed that the colonies formed after injection of mitogen-pretreated peripheral-blood lymphocytes were predominantly of erythroid type and, then, of non-differentiated cells. Only a few of them were of a mixed type, consisting of both undifferentiated cells and erythroid cells.

  13. Transcriptional programming and functional interactions within the Phytophthora sojae RXLR effector repertoire.

    Science.gov (United States)

    Wang, Qunqing; Han, Changzhi; Ferreira, Adriana O; Yu, Xiaoli; Ye, Wenwu; Tripathy, Sucheta; Kale, Shiv D; Gu, Biao; Sheng, Yuting; Sui, Yangyang; Wang, Xiaoli; Zhang, Zhengguang; Cheng, Baoping; Dong, Suomeng; Shan, Weixing; Zheng, Xiaobo; Dou, Daolong; Tyler, Brett M; Wang, Yuanchao

    2011-06-01

    The genome of the soybean pathogen Phytophthora sojae contains nearly 400 genes encoding candidate effector proteins carrying the host cell entry motif RXLR-dEER. Here, we report a broad survey of the transcription, variation, and functions of a large sample of the P. sojae candidate effectors. Forty-five (12%) effector genes showed high levels of polymorphism among P. sojae isolates and significant evidence for positive selection. Of 169 effectors tested, most could suppress programmed cell death triggered by BAX, effectors, and/or the PAMP INF1, while several triggered cell death themselves. Among the most strongly expressed effectors, one immediate-early class was highly expressed even prior to infection and was further induced 2- to 10-fold following infection. A second early class, including several that triggered cell death, was weakly expressed prior to infection but induced 20- to 120-fold during the first 12 h of infection. The most strongly expressed immediate-early effectors could suppress the cell death triggered by several early effectors, and most early effectors could suppress INF1-triggered cell death, suggesting the two classes of effectors may target different functional branches of the defense response. In support of this hypothesis, misexpression of key immediate-early and early effectors severely reduced the virulence of P. sojae transformants.

  14. X-ray induction of micronuclei in human lymphocyte subpopulations differentiated by immunoperoxidase staining

    International Nuclear Information System (INIS)

    Ban, Sadayuki; Nakano, Mimako; Cologne, J.B.

    1992-10-01

    In this report we sought to confirm the radiosensitivity of human peripheral blood lymphocyte subpopulations using a micronucleus assay. Mononucleated cells isolated from peripheral blood were irradiated with X rays. After being cultured for 3 days, cells were fixed and stained using the immunoperoxidase staining technique. Lymphocyte subpopulations were characterized by means of the monoclonal antibodies Leu4 (CD3), Leu2a (CD8), and Leu19 (CD56). Dose-response curves were obtained by scoring the number of micronuclei in binucleated cells that reacted with a specific antibody and were then stained. The dose response of CD8 + (suppressor/cytotoxic) cells was quite similar to that of CD3 + (pan T) cells. In comparison, CD56 + (natural killer) cells were significantly less sensitive, although scorable binucleated CD56 + cells made up less than 4 % of the total number of binucleated cells. (author)

  15. Analysis in cytokinesis-blocked human lymphocytes

    International Nuclear Information System (INIS)

    Catena, C.; Mattoni, A.

    1987-01-01

    Biological dosimetry can be considered as an additional method to physical dosimetry for estimating dose absorption after exposure to ionizing radiation. Fully validated as well as new promising approaches in this field are reviewed. Recent experiments, carried out in our laboratory, on the analysis of micronuclei in cytokinesis-blocked human lymphocytes are presented. The possible relevance of differential human individual response to ionizing radiation, in view of the occurrence of radiosensitive syndromes, for the estimation of the absorbed dose in human is also discussed

  16. Differential responses of human regulatory T cells (Treg and effector T cells to rapamycin.

    Directory of Open Access Journals (Sweden)

    Laura Strauss

    Full Text Available BACKGROUND: The immunosuppressive drug rapamycin (RAPA promotes the expansion of CD4(+ CD25(highFoxp3(+ regulatory T cells via mechanisms that remain unknown. Here, we studied expansion, IL-2R-gamma chain signaling, survival pathways and resistance to apoptosis in human Treg responding to RAPA. METHODOLOGY/PRINCIPAL FINDINGS: CD4(+CD25(+ and CD4(+CD25(neg T cells were isolated from PBMC of normal controls (n = 21 using AutoMACS. These T cell subsets were cultured in the presence of anti-CD3/CD28 antibodies and 1000 IU/mL IL-2 for 3 to 6 weeks. RAPA (1-100 nM was added to half of the cultures. After harvest, the cell phenotype, signaling via the PI3K/mTOR and STAT pathways, expression of survival proteins and Annexin V binding were determined and compared to values obtained with freshly-separated CD4(+CD25(high and CD4(+CD25(neg T cells. Suppressor function was tested in co-cultures with autologous CFSE-labeled CD4(+CD25(neg or CD8(+CD25(neg T-cell responders. The frequency and suppressor activity of Treg were increased after culture of CD4(+CD25(+ T cells in the presence of 1-100 nM RAPA (p<0.001. RAPA-expanded Treg were largely CD4(+CD25(highFoxp3(+ cells and were resistant to apoptosis, while CD4(+CD25(neg T cells were sensitive. Only Treg upregulated anti-apoptotic and down-regulated pro-apoptotic proteins. Treg expressed higher levels of the PTEN protein than CD4(+CD25(neg cells. Activated Treg+/-RAPA preferentially phosphorylated STAT5 and STAT3 and did not utilize the PI3K/mTOR pathway. CONCLUSIONS/SIGNIFICANCE: RAPA favors Treg expansion and survival by differentially regulating signaling, proliferation and sensitivity to apoptosis of human effector T cells and Treg after TCR/IL-2 activation.

  17. Bovine ocular squamous cell carcinoma: UV sensitivity in lymphocytes

    International Nuclear Information System (INIS)

    Lavin, M.F.; Jennings, P.A.; Hughes, D.J.

    1982-01-01

    Increased sensitivity to UV light has been demonstrated in Phytohaemagglutinin stimulated lymphocytes from normal and tumour-bearing Hereford cattle when compared to lymphocytes from other breeds. Trypan blue exclusion and inhibition of DNA synthesis were used to determine cell viability. The results obtained from time course and radiation dose experiments demonstrate biphasic survival kinetics. This is indicative of at least two separate cell populations, exhibiting differential sensitivity to UV. The increased sensitivity to UV observed in Herefords may reflect a general sensitivity to UV or alternatively a different cellular constitution in the mitogen stimulated cultures. DNA repair synthesis, measured in the presence of hydroxyurea, was of similar levels in cell cultures from Herefords and one of the control breeds. (author)

  18. CD4 T Cell Responses in Latent and Chronic Viral Infections

    Science.gov (United States)

    Walton, Senta; Mandaric, Sanja; Oxenius, Annette

    2013-01-01

    The spectrum of tasks which is fulfilled by CD4 T cells in the setting of viral infections is large, ranging from support of CD8 T cells and humoral immunity to exertion of direct antiviral effector functions. While our knowledge about the differentiation pathways, plasticity, and memory of CD4 T cell responses upon acute infections or immunizations has significantly increased during the past years, much less is still known about CD4 T cell differentiation and their beneficial or pathological functions during persistent viral infections. In this review we summarize current knowledge about the differentiation, direct or indirect antiviral effector functions, and the regulation of virus-specific CD4 T cells in the setting of persistent latent or active chronic viral infections with a particular emphasis on herpes virus infections for the former and chronic lymphocytic choriomeningitis virus infection for the latter. PMID:23717308

  19. The Genome Biology of Effector Gene Evolution in Filamentous Plant Pathogens.

    Science.gov (United States)

    Sánchez-Vallet, Andrea; Fouché, Simone; Fudal, Isabelle; Hartmann, Fanny E; Soyer, Jessica L; Tellier, Aurélien; Croll, Daniel

    2018-05-16

    Filamentous pathogens, including fungi and oomycetes, pose major threats to global food security. Crop pathogens cause damage by secreting effectors that manipulate the host to the pathogen's advantage. Genes encoding such effectors are among the most rapidly evolving genes in pathogen genomes. Here, we review how the major characteristics of the emergence, function, and regulation of effector genes are tightly linked to the genomic compartments where these genes are located in pathogen genomes. The presence of repetitive elements in these compartments is associated with elevated rates of point mutations and sequence rearrangements with a major impact on effector diversification. The expression of many effectors converges on an epigenetic control mediated by the presence of repetitive elements. Population genomics analyses showed that rapidly evolving pathogens show high rates of turnover at effector loci and display a mosaic in effector presence-absence polymorphism among strains. We conclude that effective pathogen containment strategies require a thorough understanding of the effector genome biology and the pathogen's potential for rapid adaptation. Expected final online publication date for the Annual Review of Phytopathology Volume 56 is August 25, 2018. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

  20. Nematode effector proteins: an emerging paradigm of parasitism

    Science.gov (United States)

    Phytonematodes use a stylet and secreted effectors to invade host tissues and extract nutrients to support their growth and development. The molecular function of nematode effectors is currently the subject of intense investigation. In this review, we summarize our current understanding of nematode ...

  1. A case report of gastric lymphocytic phlebitis, a rare mimic for malignancy

    Directory of Open Access Journals (Sweden)

    Daniel L. Chan

    Full Text Available Introduction: Lymphocytic phlebitis is a benign condition characterised by inflammation of the veins and rarely affects the gastrointestinal tract. Reported cases present as acute abdomen and involve the colon or small intestine. We report the fourth case of gastric lymphocytic phlebitis in the literature. Presentation of case: A 74-year-old female presented with eight weeks of abdominal pain. Findings at endoscopy were suggestive of a malignant ulcer on the greater curvature of antrum, while biopsies showed chronic gastritis without malignancy. Appearance at diagnostic laparoscopy was consistent with a malignant gastric ulcer with serosal changes. Due to persistent pain and the macroscopic appearance, she proceeded to have an open subtotal gastrectomy and D2 lymph node clearance. Despite macroscopic appearance, the microscopic examination demonstrated no malignancy, and was consistent with lymphocytic phlebitis with overlying ulceration. Discussion: This case was a mimic for gastric malignancy, with the benign diagnosis only being made after surgical resection. Gastric lymphocytic phlebitis is a rare differential diagnosis for gastric ulcers when biopsies are negative, although preoperative diagnosis is difficult given the lesions do not involve the mucosa. Conclusion: If clinical history and endoscopic findings are suspicious for malignancy, despite normal biopsies, an aggressive surgical resection remains reasonable given the rarity gastric lymphocytic phlebitis. Keywords: Lymphocytic phlebitis, Gastrectomy, Gastric vasculitis, Gastric ulcer, Case report

  2. T-bet- and STAT4-dependent IL-33 receptor expression directly promotes antiviral Th1 cell responses.

    Science.gov (United States)

    Baumann, Claudia; Bonilla, Weldy V; Fröhlich, Anja; Helmstetter, Caroline; Peine, Michael; Hegazy, Ahmed N; Pinschewer, Daniel D; Löhning, Max

    2015-03-31

    During infection, the release of damage-associated molecular patterns, so-called "alarmins," orchestrates the immune response. The alarmin IL-33 plays a role in a wide range of pathologies. Upon release, IL-33 signals through its receptor ST2, which reportedly is expressed only on CD4(+) T cells of the Th2 and regulatory subsets. Here we show that Th1 effector cells also express ST2 upon differentiation in vitro and in vivo during lymphocytic choriomeningitis virus (LCMV) infection. The expression of ST2 on Th1 cells was transient, in contrast to constitutive ST2 expression on Th2 cells, and marked highly activated effector cells. ST2 expression on virus-specific Th1 cells depended on the Th1-associated transcription factors T-bet and STAT4. ST2 deficiency resulted in a T-cell-intrinsic impairment of LCMV-specific Th1 effector responses in both mixed bone marrow-chimeric mice and adoptive cell transfer experiments. ST2-deficient virus-specific CD4(+) T cells showed impaired expansion, Th1 effector differentiation, and antiviral cytokine production. Consequently, these cells mediated little virus-induced immunopathology. Thus, IL-33 acts as a critical and direct cofactor to drive antiviral Th1 effector cell activation, with implications for vaccination strategies and immunotherapeutic approaches.

  3. Principles and applications of TAL effectors for plant physiology and metabolism.

    Science.gov (United States)

    Bogdanove, Adam J

    2014-06-01

    Recent advances in DNA targeting allow unprecedented control over gene function and expression. Targeting based on TAL effectors is arguably the most promising for systems biology and metabolic engineering. Multiple, orthogonal TAL-effector reagents of different types can be used in the same cell. Furthermore, variation in base preferences of the individual structural repeats that make up the TAL effector DNA recognition domain makes targeting stringency tunable. Realized applications range from genome editing to epigenome modification to targeted gene regulation to chromatin labeling and capture. The principles that govern TAL effector DNA recognition make TAL effectors well suited for applications relevant to plant physiology and metabolism. TAL effector targeting has merits that are distinct from those of the RNA-based DNA targeting CRISPR/Cas9 system. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Intraspecies Competition in Serratia marcescens Is Mediated by Type VI-Secreted Rhs Effectors and a Conserved Effector-Associated Accessory Protein.

    Science.gov (United States)

    Alcoforado Diniz, Juliana; Coulthurst, Sarah J

    2015-07-01

    The type VI secretion system (T6SS) is widespread in Gram-negative bacteria and can deliver toxic effector proteins into eukaryotic cells or competitor bacteria. Antibacterial T6SSs are increasingly recognized as key mediators of interbacterial competition and may contribute to the outcome of many polymicrobial infections. Multiple antibacterial effectors can be delivered by these systems, with diverse activities against target cells and distinct modes of secretion. Polymorphic toxins containing Rhs repeat domains represent a recently identified and as-yet poorly characterized class of T6SS-dependent effectors. Previous work had revealed that the potent antibacterial T6SS of the opportunistic pathogen Serratia marcescens promotes intraspecies as well as interspecies competition (S. L. Murdoch, K. Trunk, G. English, M. J. Fritsch, E. Pourkarimi, and S. J. Coulthurst, J Bacteriol 193:6057-6069, 2011, http://dx.doi.org/10.1128/JB.05671-11). In this study, two new Rhs family antibacterial effectors delivered by this T6SS have been identified. One of these was shown to act as a DNase toxin, while the other contains a novel, cytoplasmic-acting toxin domain. Importantly, using S. marcescens, it has been demonstrated for the first time that Rhs proteins, rather than other T6SS-secreted effectors, can be the primary determinant of intraspecies competition. Furthermore, a new family of accessory proteins associated with T6SS effectors has been identified, exemplified by S. marcescens EagR1, which is specifically required for deployment of its associated Rhs effector. Together, these findings provide new insight into how bacteria can use the T6SS to deploy Rhs-family effectors and mediate different types of interbacterial interactions. Infectious diseases caused by bacterial pathogens represent a continuing threat to health and economic prosperity. To counter this threat, we must understand how such organisms survive and prosper. The type VI secretion system is a weapon that

  5. Increased frequency of CD8+ and CD4+ regulatory T cells in chronic lymphocytic leukemia: association with disease progression.

    Science.gov (United States)

    Jadidi-Niaragh, Farhad; Yousefi, Mehdi; Memarian, Ali; Hojjat-Farsangi, Mohammad; Khoshnoodi, Jalal; Razavi, Seyed Mohsen; Jeddi-Tehrani, Mahmood; Shokri, Fazel

    2013-02-01

    Little is known regarding the immunobiology of regulatory T (Treg) cells in hematopoietic malignancies, particularly in chronic lymphocytic leukemia (CLL). In the present study, we showed that the frequencies of CD8(+) and CD4(+) Treg cells were significantly increased in progressive as compared with indolent CLL patients and normal subjects. Enriched CD4(+) Treg cells induced a similar level of inhibition in polyclonally activated B cells and effector T cells from CLL patients and normal subjects. Our results suggest that the increase in circulating Treg cells may result in downregulation of tumor-specific immune response, leading to tumor expansion and disease progression.

  6. Development of a serum-free medium for in vitro expansion of human cytotoxic T lymphocytes using a statistical design

    Directory of Open Access Journals (Sweden)

    Lee Gyun

    2010-09-01

    Full Text Available Abstract Background Serum-containing medium (SCM, which has a number of poorly defined components with varying concentrations, hampers standardization of lymphocyte cultures. In order to develop a serum-free medium (SFM for the expansion of human lymphocytes from peripheral blood mononuclear cells (PBMCs, a statistical optimization approach based on a fractional factorial method and a response surface method was adopted. A basal medium was prepared by supplementing RPMI1640 medium with insulin, albumin, ferric citrate, ethanolamine, fatty acids, glutamine, sodium pyruvate, 2-mercaptoethanol, 1-thioglycerol, nonessential amino acids, and vitamins. We identified additional positive determinants and their optimal concentrations for cell growth through a statistical analysis. Results From a statistical analysis using the fractional factorial method, cholesterol and polyamine supplement were identified as positive determinants for cell growth. Their optimal concentrations were determined by the response surface method. The maximum viable cell concentration in the developed SFM was enhanced by more than 1.5-fold when compared to that in RPMI1640 supplemented with 10% fetal bovine serum (FBS. Furthermore, a cytotoxicity assay and an enzyme-linked immunospot assay revealed that the effector function of cytotoxic T lymphocytes generated from PBMCs grown in SFM, by stimulation of peptide-presenting dendritic cells, was retained or even better than that in SCM. Conclusions The use of a developed SFM with cholesterol and polyamine supplement for human lymphocyte culture resulted in better growth without loss of cellular function when compared to SCM.

  7. Development of a serum-free medium for in vitro expansion of human cytotoxic T lymphocytes using a statistical design.

    Science.gov (United States)

    Jeon, Min Kyoung; Lim, Jong-Baeck; Lee, Gyun Min

    2010-09-21

    Serum-containing medium (SCM), which has a number of poorly defined components with varying concentrations, hampers standardization of lymphocyte cultures. In order to develop a serum-free medium (SFM) for the expansion of human lymphocytes from peripheral blood mononuclear cells (PBMCs), a statistical optimization approach based on a fractional factorial method and a response surface method was adopted. A basal medium was prepared by supplementing RPMI1640 medium with insulin, albumin, ferric citrate, ethanolamine, fatty acids, glutamine, sodium pyruvate, 2-mercaptoethanol, 1-thioglycerol, nonessential amino acids, and vitamins. We identified additional positive determinants and their optimal concentrations for cell growth through a statistical analysis. From a statistical analysis using the fractional factorial method, cholesterol and polyamine supplement were identified as positive determinants for cell growth. Their optimal concentrations were determined by the response surface method. The maximum viable cell concentration in the developed SFM was enhanced by more than 1.5-fold when compared to that in RPMI1640 supplemented with 10% fetal bovine serum (FBS). Furthermore, a cytotoxicity assay and an enzyme-linked immunospot assay revealed that the effector function of cytotoxic T lymphocytes generated from PBMCs grown in SFM, by stimulation of peptide-presenting dendritic cells, was retained or even better than that in SCM. The use of a developed SFM with cholesterol and polyamine supplement for human lymphocyte culture resulted in better growth without loss of cellular function when compared to SCM.

  8. Cytokine Secreting Microparticles Engineer the Fate and the Effector Functions of T-Cells.

    Science.gov (United States)

    Majedi, Fatemeh S; Hasani-Sadrabadi, Mohammad Mahdi; Kidani, Yoko; Thauland, Timothy J; Moshaverinia, Alireza; Butte, Manish J; Bensinger, Steven J; Bouchard, Louis-S

    2018-02-01

    T-cell immunotherapy is a promising approach for cancer, infection, and autoimmune diseases. However, significant challenges hamper its therapeutic potential, including insufficient activation, delivery, and clonal expansion of T-cells into the tumor environment. To facilitate T-cell activation and differentiation in vitro, core-shell microparticles are developed for sustained delivery of cytokines. These particles are enriched by heparin to enable a steady release of interleukin-2 (IL-2), the major T-cell growth factor, over 10+ d. The controlled delivery of cytokines is used to steer lineage specification of cultured T-cells. This approach enables differentiation of T-cells into central memory and effector memory subsets. It is shown that the sustained release of stromal cell-derived factor 1α could accelerate T-cell migration. It is demonstrated that CD4+ T-cells could be induced to high concentrations of regulatory T-cells through controlled release of IL-2 and transforming growth factor beta. It is found that CD8+ T-cells that received IL-2 from microparticles are more likely to gain effector functions as compared with traditional administration of IL-2. Culture of T-cells within 3D scaffolds that contain IL-2-secreting microparticles enhances proliferation as compared with traditional, 2D approaches. This yield a new method to control the fate of T-cells and ultimately to new strategies for immune therapy. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Differential production of immunoglobulin classes and subclasses by mucosal-type human B-lymphocytes exposed in vitro to CpG oligodeoxynucleotides.

    Science.gov (United States)

    Cognasse, Fabrice; Acquart, Sophie; Beniguel, Lydie; Sabido, Odile; Chavarin, Patricia; Genin, Christian; Garraud, Olivier

    2005-01-01

    As B-lymphocytes play an important role in innate and adaptive immunity, we aimed to examine the effects of CpG oligodeoxynucleotides (ODNs) on purified tonsil-originating CD19+ B-cells, representing mucosal B-cells. We screened various K-type ODNs, reactive with human B-cells, and tested for the production of immunoglobulins in vitro. Using one CpG-ODN, DSP30, we observed that it could upregulate not only Toll-like receptor 9 (TLR9) mRNA expression in activated B-cells, but also the early expression of CD69 followed by the sequential expression of CD80, CD86 and the nuclear factor (NF)-kappaB pathway. Furthermore, mRNA expression of certain B-cell-derived cytokines was influenced by exposure to DSP30, with a strong upregulation of interleukin 6 (IL-6) and downregulation of IL1-beta. Stimulation of B-cells, co-stimulated with IL-2, IL-10 and soluble CD40 ligand (sCD40L) with different CpG-ODNs, had differing effects on the terminal differentiation in vitro of B-cells into immunoglobulin-secreting cells. TLR9 is involved in innate immunity and the recognition of bound CpG DNA from invading bacterial pathogens. As tonsillar B-cells are mucosal-type B-lymphocytes, this study suggests that CpG-ODNs show promise as mucosal adjuvants in modulating the local production of immunoglobulins of certain classes and subclasses, a crucial issue in vaccine perspectives.

  10. Genomic characterisation of the effector complement of the potato cyst nematode Globodera pallida.

    Science.gov (United States)

    Thorpe, Peter; Mantelin, Sophie; Cock, Peter Ja; Blok, Vivian C; Coke, Mirela C; Eves-van den Akker, Sebastian; Guzeeva, Elena; Lilley, Catherine J; Smant, Geert; Reid, Adam J; Wright, Kathryn M; Urwin, Peter E; Jones, John T

    2014-10-23

    The potato cyst nematode Globodera pallida has biotrophic interactions with its host. The nematode induces a feeding structure - the syncytium - which it keeps alive for the duration of the life cycle and on which it depends for all nutrients required to develop to the adult stage. Interactions of G. pallida with the host are mediated by effectors, which are produced in two sets of gland cells. These effectors suppress host defences, facilitate migration and induce the formation of the syncytium. The recent completion of the G. pallida genome sequence has allowed us to identify the effector complement from this species. We identify 128 orthologues of effectors from other nematodes as well as 117 novel effector candidates. We have used in situ hybridisation to confirm gland cell expression of a subset of these effectors, demonstrating the validity of our effector identification approach. We have examined the expression profiles of all effector candidates using RNAseq; this analysis shows that the majority of effectors fall into one of three clusters of sequences showing conserved expression characteristics (invasive stage nematode only, parasitic stage only or invasive stage and adult male only). We demonstrate that further diversity in the effector pool is generated by alternative splicing. In addition, we show that effectors target a diverse range of structures in plant cells, including the peroxisome. This is the first identification of effectors from any plant pathogen that target this structure. This is the first genome scale search for effectors, combined to a life-cycle expression analysis, for any plant-parasitic nematode. We show that, like other phylogenetically unrelated plant pathogens, plant parasitic nematodes deploy hundreds of effectors in order to parasitise plants, with different effectors required for different phases of the infection process.

  11. Fibre optic sensor on robot end effector for flexible assembly

    International Nuclear Information System (INIS)

    Yung, K.L.; Lau, W.S.; Choi, C.K.; Shan, Y.Y.

    1995-01-01

    A fibre optic sensor system was constructed for use on robot end effectors for flexible assembly. The sensor detected the deviations between robot end effector and the workpiece. The signal was fed back to robot controller to shift the end effector until the centre of end effector and the centre of workpiece were aligned at the correct orientation. Then workpiece can be grasped symmetrically. Sensor fusion concept was used to guard against sensor system failure. Fuzzy linguistic variable and control rule concept were introduced in the sensor integration. The experimental setup for the sensor integrated system was shown. The accuracy was also discussed

  12. Impaired T-lymphocyte colony formation by cord blood mononuclear cells

    International Nuclear Information System (INIS)

    Herrod, H.G.; Valenski, W.R.

    1982-01-01

    When compared to adult mononuclear cells, cord blood mononuclear cells demonstrated significantly decreased T-lymphocyte colony formation (1351 +/- 643 vs 592 +/- 862, P less than 0.01). This diminished colony-forming activity did not appear to be associated with impaired responsiveness to the stimulant phytohemagglutinin or with excessive suppressor-cell activity. Irradiation reduced the colony-forming capacity of cord blood mononuclear cells more than it did that of adult mononuclear cells. Depletion of adherent cells reduced cord blood mononuclear-cell colony-forming capacity by 40%, while similar treatment reduced adult colony formation by 10%. Lymphocyte proliferation in liquid culture of cord and adult cells was minimally affected by these procedures. The colony-forming capacity of cord blood could be enhanced by the addition of irradiated adult cells (284 +/- 72 vs 752 +/- 78, P less than 0.01). This enhancement was demonstrated to be due to a soluble factor produced by a population of irradiated adult cells depleted of the OKT8+ subpopulation of lymphocytes. These results indicate that the progenitor cells of T-lymphocyte colonies in cord blood have distinct biologic characteristics when compared to colony progenitors present in adult blood. This assay may prove to be useful in our efforts to understand the differentiation of T-cell function in man

  13. A case report of gastric lymphocytic phlebitis, a rare mimic for malignancy.

    Science.gov (United States)

    Chan, Daniel L; Ravindran, Praveen; Chua, Dorothy; Smith, Jason D; Wong, King S; Ghusn, Michael A

    2017-01-01

    Lymphocytic phlebitis is a benign condition characterised by inflammation of the veins and rarely affects the gastrointestinal tract. Reported cases present as acute abdomen and involve the colon or small intestine. We report the fourth case of gastric lymphocytic phlebitis in the literature. A 74-year-old female presented with eight weeks of abdominal pain. Findings at endoscopy were suggestive of a malignant ulcer on the greater curvature of antrum, while biopsies showed chronic gastritis without malignancy. Appearance at diagnostic laparoscopy was consistent with a malignant gastric ulcer with serosal changes. Due to persistent pain and the macroscopic appearance, she proceeded to have an open subtotal gastrectomy and D2 lymph node clearance. Despite macroscopic appearance, the microscopic examination demonstrated no malignancy, and was consistent with lymphocytic phlebitis with overlying ulceration. This case was a mimic for gastric malignancy, with the benign diagnosis only being made after surgical resection. Gastric lymphocytic phlebitis is a rare differential diagnosis for gastric ulcers when biopsies are negative, although preoperative diagnosis is difficult given the lesions do not involve the mucosa. If clinical history and endoscopic findings are suspicious for malignancy, despite normal biopsies, an aggressive surgical resection remains reasonable given the rarity gastric lymphocytic phlebitis. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. Nanorobotic end-effectors: Design, fabrication, and in situ characterization

    Science.gov (United States)

    Fan, Zheng

    Nano-robotic end-effectors have promising applications for nano-fabrication, nano-manufacturing, nano-optics, nano-medical, and nano-sensing; however, low performances of the conventional end-effectors have prevented the widespread utilization of them in various fields. There are two major difficulties in developing the end-effectors: their nano-fabrication and their advanced characterization in the nanoscale. Here we introduce six types of end-effectors: the nanotube fountain pen (NFP), the super-fine nanoprobe, the metal-filled carbon nanotube (m CNT)-based sphere-on-pillar (SOP) nanoantennas, the tunneling nanosensor, and the nanowire-based memristor. The investigations on the NFP are focused on nano-fluidics and nano-fabrications. The NFP could direct write metallic "inks" and fabricating complex metal nanostructures from 0D to 3D with a position servo control, which is critically important to future large-scale, high-throughput nanodevice production. With the help of NFP, we could fabricate the end-effectors such as super-fine nanoprobe and m CNT-based SOP nanoantennas. Those end-effectors are able to detect local flaws or characterize the electrical/mechanical properties of the nanostructure. Moreover, using electron-energy-loss-spectroscopy (EELS) technique during the operation of the SOP optical antenna opens a new basis for the application of nano-robotic end-effectors. The technique allows advanced characterization of the physical changes, such as carrier diffusion, that are directly responsible for the device's properties. As the device was coupled with characterization techniques of scanning-trasmission-electron-microscopy (STEM), the development of tunneling nanosensor advances this field of science into quantum world. Furthermore, the combined STEM-EELS technique plays an important role in our understanding of the memristive switching performance in the nanowire-based memristor. The developments of those nano-robotic end-effectors expend the study

  15. Investigation of a bio-inspired lift-enhancing effector on a 2D airfoil.

    Science.gov (United States)

    Johnston, Joe; Gopalarathnam, Ashok

    2012-09-01

    A flap mounted on the upper surface of an airfoil, called a 'lift-enhancing effector', has been shown in wind tunnel tests to have a similar function to a bird's covert feathers, which rise off the wing's surface in response to separated flows. The effector, fabricated from a thin Mylar sheet, is allowed to rotate freely about its leading edge. The tests were performed in the NCSU subsonic wind tunnel at a chord Reynolds number of 4 × 10(5). The maximum lift coefficient with the effector was the same as that for the clean airfoil, but was maintained over an angle-of-attack range from 12° to almost 20°, resulting in a very gentle stall behavior. To better understand the aerodynamics and to estimate the deployment angle of the free-moving effector, fixed-angle effectors fabricated out of stiff wood were also tested. A progressive increase in the stall angle of attack with increasing effector angle was observed, with diminishing returns beyond the effector angle of 60°. Drag tests on both the free-moving and fixed effectors showed a marked improvement in drag at high angles of attack. Oil flow visualization on the airfoil with and without the fixed-angle effectors proved that the effector causes the separation point to move aft on the airfoil, as compared to the clean airfoil. This is thought to be the main mechanism by which an effector improves both lift and drag. A comparison of the fixed-effector results with those from the free-effector tests shows that the free effector's deployment angle is between 30° and 45°. When operating at and beyond the clean airfoil's stall angle, the free effector automatically deploys to progressively higher angles with increasing angles of attack. This slows down the rapid upstream movement of the separation point and avoids the severe reduction in the lift coefficient and an increase in the drag coefficient that are seen on the clean airfoil at the onset of stall. Thus, the effector postpones the stall by 4-8° and makes the

  16. Evaluation of an mRNA lipofection procedure for human dendritic cells and induction of cytotoxic T lymphocytes against enhanced green fluorescence protein.

    Science.gov (United States)

    Okano, Kozue; Fukui, Mikiko; Suehiro, Yutaka; Hamanaka, Yuichiro; Imai, Kohzoh; Hinoda, Yuji

    2003-01-01

    We utilized an mRNA lipofection procedure in human dendritic cells (DCs) and attempted to induce cytotoxic T lymphocytes (CTLs) against enhanced green fluorescence protein (EGFP). EGFP mRNA was transfected into phytohemagglutinin (PHA)-stimulated lymphocytes or adherent peripheral blood mononuclear cell-derived DCs using a liposomal reagent. Lipofection efficiency was measured by flow cytometry. In PHA-stimulated lymphocytes, increasing concentrations of liposome or mRNA increased EGFP expression levels by up to 64.4%, but caused a decrease in cell viability. A similar trend was also observed in DCs. For 70% DC viability, the concentration of liposomes was 24 microl/ml, and the mRNA concentration was 6 microg/ml. Under these conditions, ELISPOT and (51)Cr release assays were performed on CD8+ T cells stimulated twice with EGFP mRNA-transfected DCs. The number of interferon-gamma-producing cells was increased when the CD8+ T cells were cocultured for 24 h with PHA-stimulated lymphocytes transfected with EGFP mRNA. The level of specific lysis of EGFP mRNA-transfected DCs also increased to approximately 80%, with an effector to target ratio of 40:1. These data suggest that EGFP is immunogenic for human T cells, confirming that our lipofection procedure may be of use for inducing specific CTLs. Copyright 2003 S. Karger AG, Basel

  17. Design and force analysis of end-effector for plug seedling transplanter.

    Science.gov (United States)

    Jiang, Zhuohua; Hu, Yang; Jiang, Huanyu; Tong, Junhua

    2017-01-01

    Automatic transplanters have been very important in greenhouses since the popularization of seedling nurseries. End-effector development is a key technology for transplanting plug seedlings. Most existing end-effectors have problems with holding root plugs or releasing plugs. An efficient end-effector driven by a linear pneumatic cylinder was designed in this study, which could hold root plugs firmly and release plugs easily. This end-effector with four needles could clamp the plug simultaneously while the needles penetrate into the substrate. The depth and verticality of the needles could be adjusted conveniently for different seedling trays. The effectiveness of this end-effector was tested by a combinational trial examining three seedling nursery factors (the moisture content of the substrate, substrate bulk density and the volume proportion of substrate ingredients). Results showed that the total transplanting success rate for the end-effector was 100%, and the root plug harm rate was below 17%. A force measure system with tension and pressure transducers was installed on the designed end-effector. The adhesive force FL between the root plug and the cell of seedling trays and the extrusion force FK on the root plug were measured and analyzed. The results showed that all three variable factors and their interactions had significant effects on the extrusion force. Each factor had a significant effect on adhesive force. Additionally, it was found that the end-effector did not perform very well when the value of FK/FL was beyond the range of 5.99~8.67. This could provide a scientific basis for end-effector application in transplanting.

  18. The determination of lymphoid cell chimerism using peripheral blood lymphocytes from murine bone marrow chimeras

    International Nuclear Information System (INIS)

    Skidmore, B.J.; Miller, L.S.

    1978-01-01

    A simple, rapid and accurate method was devised for determining lymphoid cell chimerism in bone marrow-reconstituted mice. Chimeras were produced by reconstituting lethally irradiated mice with semi-allogeneic bone marrow cells. Lymphocytes from the peripheral blood of individual chimeric mice were purified by sedimentation in dextran solution and differential flotation in Ficoll-Hypaque gradients. From 250-500 μl of blood, 1-7 x 10 5 cells were routinely obtained. The extent of chimerism was determined serologically by using peripheral blood lymphocytes as target cells in a dye exclusion microcytotoxicity assay. Using this new technique, approximately 80% of the reconstituted mice were found to be repopulated with lymphocytes of the donor type. (Auth.)

  19. Histone deacetylase inhibitors impair the elimination of HIV-infected cells by cytotoxic T-lymphocytes.

    Directory of Open Access Journals (Sweden)

    Richard Brad Jones

    2014-08-01

    Full Text Available Resting memory CD4+ T-cells harboring latent HIV proviruses represent a critical barrier to viral eradication. Histone deacetylase inhibitors (HDACis, such as suberanilohydroxamic acid (SAHA, romidepsin, and panobinostat have been shown to induce HIV expression in these resting cells. Recently, it has been demonstrated that the low levels of viral gene expression induced by a candidate HDACi may be insufficient to cause the death of infected cells by viral cytopathic effects, necessitating their elimination by immune effectors, such as cytotoxic T-lymphocytes (CTL. Here, we study the impact of three HDACis in clinical development on T-cell effector functions. We report two modes of HDACi-induced functional impairment: i the rapid suppression of cytokine production from viable T-cells induced by all three HDACis ii the selective death of activated T-cells occurring at later time-points following transient exposures to romidepsin or, to a lesser extent, panobinostat. As a net result of these factors, HDACis impaired CTL-mediated IFN-γ production, as well as the elimination of HIV-infected or peptide-pulsed target cells, both in liquid culture and in collagen matrices. Romidepsin exerted greater inhibition of antiviral function than SAHA or panobinostat over the dose ranges tested. These data suggest that treatment with HDACis to mobilize the latent reservoir could have unintended negative impacts on the effector functions of CTL. This could influence the effectiveness of HDACi-based eradication strategies, by impairing elimination of infected cells, and is a critical consideration for trials where therapeutic interruptions are being contemplated, given the importance of CTL in containing rebound viremia.

  20. New clues in the nucleus: Transcriptional reprogramming in effector-triggered immunity

    Directory of Open Access Journals (Sweden)

    SAIKAT eBHATTACHARJEE

    2013-09-01

    Full Text Available The robustness of plant effector-triggered immunity is correlated with massive alterations of the host transcriptome. Yet the molecular mechanisms that cause and underlie this reprogramming remain obscure. Here we will review recent advances in deciphering nuclear functions of plant immune receptors and of associated proteins. Important open questions remain, such as the identities of the primary transcription factors involved in control of effector-triggered immune responses, and indeed whether this can be generalized or whether particular effector-resistance protein interactions impinge on distinct sectors in the transcriptional response web. Multiple lines of evidence have implicated WRKY transcription factors at the core of responses to microbe-associated molecular patterns and in intersections with effector-triggered immunity. Recent findings from yeast two-hybrid studies suggest that members of the TCP transcription factor family are targets of several effectors from diverse pathogens. Additional transcription factor families that are directly or indirectly involved in effector-triggered immunity are likely to be identified.

  1. Flow Cytometric Analysis of Leishmania Reactive CD4+/CD8+ Lymphocyte Proliferation in Cutaneous Leishmaniasis

    Directory of Open Access Journals (Sweden)

    H Keshavarz

    2008-12-01

    Full Text Available Background: Determination of the division history of T cells in vitro is helpful in the study of effector mechanisms against infections. Technique described here uses the intracellular fluorescent label carboxyfluorescein diacetate succinimidyl ester (CFSE to monitor the proliferation. Methods: In a cross sectional study, blood samples were collected from 7 volunteers with history of cutaneous leishmania­sis (CL and one healthy control from endemic areas in Isfahan province who referred to the Center for Research and Training in Skin Diseases and Leprosy (CRTSDL, then CD4+/CD8+ lymphocytes and CD14+ monocytes were isolated from peri­pheral blood mononuclear cells (PBMC using mAbs and magnetic nanoparticles. CFSE labeled CD4+ or CD8+ lympho­cytes cultured with autologous monocytes in the presence of PHA, SLA, live Leishmania major or as control with­out sti­mulation. Cells were harvested after 7 days and were analyzed using flow cytometry. Results: Five consecutive divisions were monitored separately. Stimulation of CD4+ or CD8+ lymphocytes from CL sub­jects with SLA showed a significant difference in proliferation comparing with unstimulated cells (P< 0.05. The signifi­cant difference in the percentages of CD4+ cells stimulated with SLA was revealed at different divisions for each subject. In CD8+ lymphocyte, significant stronger stimulation of SLA was evident later in the proliferation process. The mean number of divisions in both CD4+/CD8+ lymphocytes stimulated with SLA was significantly greater than when stimulated with live L. major (P=0.007 / P=0.012, respectively Conclusion: The percentage of divided cells might be calculated separately in each division. The cells remained active following CFSE staining and there is possibility of functional analysis simultaneously.

  2. Biodistribution of radiolabeled lymphocytes

    International Nuclear Information System (INIS)

    Fawwaz, R.A.; Oluwole, S.; Wang, T.S.; Kuromoto, N.; Iga, C.; Hardy, M.A.; Alderson, P.O.

    1985-01-01

    Factors that might affect the biodistribution and clinical utility of radiolabeled lymphocytes were evaluated in experimental animals. Indium-111 (In-111) labeled lymphocytes obtained from peripheral blood, lymph node, or spleen were found in significant amounts in the lymphoid tissues of Lewis rats as early as 3 hours after infusion. A progressive increase in nodal activity with concomitant fall of activity in other organs followed, indicating active recirculation of the lymphocytes. In vitro irradiation of the In-111 labeled lymphocytes resulted in no detectable lymphocyte recirculation and/or reduced localization in lymphoid tissue. Splenectomized animals and those sensitized to an organ allograft before cell infusion showed increased activity in their bone marrow. These results suggest that the source of the injected cells, cell irradiation dose level and host sensitization should be considered when radiolabeled lymphocytes are being prepared for use in clinical diagnosis and therapy

  3. Design and force analysis of end-effector for plug seedling transplanter.

    Directory of Open Access Journals (Sweden)

    Zhuohua Jiang

    Full Text Available Automatic transplanters have been very important in greenhouses since the popularization of seedling nurseries. End-effector development is a key technology for transplanting plug seedlings. Most existing end-effectors have problems with holding root plugs or releasing plugs. An efficient end-effector driven by a linear pneumatic cylinder was designed in this study, which could hold root plugs firmly and release plugs easily. This end-effector with four needles could clamp the plug simultaneously while the needles penetrate into the substrate. The depth and verticality of the needles could be adjusted conveniently for different seedling trays. The effectiveness of this end-effector was tested by a combinational trial examining three seedling nursery factors (the moisture content of the substrate, substrate bulk density and the volume proportion of substrate ingredients. Results showed that the total transplanting success rate for the end-effector was 100%, and the root plug harm rate was below 17%. A force measure system with tension and pressure transducers was installed on the designed end-effector. The adhesive force FL between the root plug and the cell of seedling trays and the extrusion force FK on the root plug were measured and analyzed. The results showed that all three variable factors and their interactions had significant effects on the extrusion force. Each factor had a significant effect on adhesive force. Additionally, it was found that the end-effector did not perform very well when the value of FK/FL was beyond the range of 5.99~8.67. This could provide a scientific basis for end-effector application in transplanting.

  4. Mathematical modeling of the implications of dominant tolerance for tumor biology and the response to combination therapy

    International Nuclear Information System (INIS)

    Leon, Kalet; Garcia, Karina; Lage, Agustin

    2008-01-01

    The existence of regulatory T lymphocytes (Tregs) that can control effector lymphocytes within the context of autoimmune, infectious and tumoral diseases is definitely accepted in current immunological research. Tregs confirm the theory of dominant tolerance, which holds that the choice of antigen rejection or tolerance in the immune system is the result of a dynamic equilibrium between populations of effector and regulatory T lymphocytes. The present paper summarizes the result of a recent theoretical study using mathematical modeling to analyze the dynamic interplay between T lymphocyte populations in the absence or presence of tumors and in response to different therapeutic treatments. The resulting model, developed at the Center of Molecular Immunology, which received an award from the Cuban Academy of Sciences in 2002, includes tumor cells and can simulate the effect of antitumoral mono- or combination therapies, by taking into account the way in which certain dynamic properties of tumors can, under specific circumstances, lead to the spontaneous expansion of Tregs populations. One of the advantages of the model is the prediction of several new strategies for the differential treatment of tumors, depending upon their ability of inducing the expansion of regulatory T cells. This is the first model available for the study of the impact of Tregs on the growth of malignant tumors, with results supported by international publications. Additionally, the model predicts the practical effects of several combination therapies, including vaccines, the excision of the tumor and depletion of lymphocyte populations. (Author)

  5. Type II membrane protein CD69 regulates the formation of resting T-helper memory.

    Science.gov (United States)

    Shinoda, Kenta; Tokoyoda, Koji; Hanazawa, Asami; Hayashizaki, Koji; Zehentmeier, Sandra; Hosokawa, Hiroyuki; Iwamura, Chiaki; Koseki, Haruhiko; Tumes, Damon J; Radbruch, Andreas; Nakayama, Toshinori

    2012-05-08

    Memory T-helper (Th) lymphocytes are crucial for the maintenance of acquired immunity to eliminate infectious pathogens. We have previously demonstrated that most memory Th lymphocytes reside and rest on stromal niches of the bone marrow (BM). Little is known, however, regarding the molecular basis for the generation and maintenance of BM memory Th lymphocytes. Here we show that CD69-deficient effector CD4 T lymphocytes fail to relocate into and persist in the BM and therefore to differentiate into memory cells. Consequently, CD69-deficient CD4 T cells fail to facilitate the production of high-affinity antibodies and the generation of BM long-lived plasma cells in the late phase of immune responses. Thus, CD69 is critical for the generation and maintenance of professional memory Th lymphocytes, which can efficiently help humoral immunity in the late phase. The deficit of immunological memory in CD69-deficient mice also highlights the essential role of BM for the establishment of Th memory.

  6. Forging T-Lymphocyte Identity: Intersecting Networks of Transcriptional Control.

    Science.gov (United States)

    Rothenberg, Ellen V; Ungerbäck, Jonas; Champhekar, Ameya

    2016-01-01

    T-lymphocyte development branches off from other lymphoid developmental programs through its requirement for sustained environmental signals through the Notch pathway. In the thymus, Notch signaling induces a succession of T-lineage regulatory factors that collectively create the T-cell identity through distinct steps. This process involves both the staged activation of T-cell identity genes and the staged repression of progenitor-cell-inherited regulatory genes once their roles in self-renewal and population expansion are no longer needed. With the recent characterization of innate lymphoid cells (ILCs) that share transcriptional regulation programs extensively with T-cell subsets, T-cell identity can increasingly be seen as defined in modular terms, as the processes selecting and actuating effector function are potentially detachable from the processes generating and selecting clonally unique T-cell receptor structures. The developmental pathways of different classes of T cells and ILCs are distinguished by the numbers of prerequisites of gene rearrangement, selection, and antigen contact before the cells gain access to nearly common regulatory mechanisms for choosing effector function. Here, the major classes of transcription factors that interact with Notch signals during T-lineage specification are discussed in terms of their roles in these programs, the evidence for their spectra of target genes at different stages, and their cross-regulatory and cooperative actions with each other. Specific topics include Notch modulation of PU.1 and GATA-3, PU.1-Notch competition, the relationship between PU.1 and GATA-3, and the roles of E proteins, Bcl11b, and GATA-3 in guiding acquisition of T-cell identity while avoiding redirection to an ILC fate. © 2016 Elsevier Inc. All rights reserved.

  7. Tau, APP, NCT and BACE1 in lymphocytes through cognitively normal ageing and neuropathology

    Directory of Open Access Journals (Sweden)

    MARISOL HERRERA-RIVERO

    2013-01-01

    Full Text Available Although Alzheimer's disease is a brain disorder, a number of peripheral alterations have been found in these patients; however, little is known about how the key genes involved in the pathophysiology express in peripheral cells such as lymphocytes during normal compared to neuropathological ageing. We analysed the expression of tau, of the amyloid precursor protein, of nicastrin and of the β-site APP cleaving enzyme genes by RT-PCR in lymphocytes from a small group of late-onset Alzheimer's disease patients, from aged patients suffering from neuropsychological conditions different from Alzheimer's and from cognitively healthy subjects divided in four groups by age. We also investigated correlations between gene expression and levels of blood pressure, glucose, total cholesterol and triglycerides as risk factors for Alzheimer's. Results show no tau expression in lymphocytes, a lack of detection of nicastrin expression in Alzheimer's patients and correlations between the medical conditions studied and gene expression in lymphocytes. We believe nicastrin gene expression in lymphocytes should be considered of interest for further analyses in a wider population to investigate whether it might represent a potential biomarker to differentiate Alzheimer's from other neuropsychological disorders.

  8. Global impact of Salmonella type III secretion effector SteA on host cells

    International Nuclear Information System (INIS)

    Cardenal-Muñoz, Elena; Gutiérrez, Gabriel; Ramos-Morales, Francisco

    2014-01-01

    Highlights: • We analyzed HeLa cells transcriptome in response to Salmonella SteA. • Significant differential expression was detected for 58 human genes. • They are involved in ECM organization and regulation of some signaling pathways. • Cell death, cell adhesion and cell migration were decreased in SteA-expressing cells. • These results contribute to understand the role of SteA during infections. - Abstract: Salmonella enterica is a Gram-negative bacterium that causes gastroenteritis, bacteremia and typhoid fever in several animal species including humans. Its virulence is greatly dependent on two type III secretion systems, encoded in pathogenicity islands 1 and 2. These systems translocate proteins called effectors into eukaryotic host cell. Effectors interfere with host signal transduction pathways to allow the internalization of pathogens and their survival and proliferation inside vacuoles. SteA is one of the few Salmonella effectors that are substrates of both type III secretion systems. Here, we used gene arrays and bioinformatics analysis to study the genetic response of human epithelial cells to SteA. We found that constitutive synthesis of SteA in HeLa cells leads to induction of genes related to extracellular matrix organization and regulation of cell proliferation and serine/threonine kinase signaling pathways. SteA also causes repression of genes related to immune processes and regulation of purine nucleotide synthesis and pathway-restricted SMAD protein phosphorylation. In addition, a cell biology approach revealed that epithelial cells expressing steA show altered cell morphology, and decreased cytotoxicity, cell–cell adhesion and migration

  9. Global impact of Salmonella type III secretion effector SteA on host cells

    Energy Technology Data Exchange (ETDEWEB)

    Cardenal-Muñoz, Elena; Gutiérrez, Gabriel; Ramos-Morales, Francisco

    2014-07-11

    Highlights: • We analyzed HeLa cells transcriptome in response to Salmonella SteA. • Significant differential expression was detected for 58 human genes. • They are involved in ECM organization and regulation of some signaling pathways. • Cell death, cell adhesion and cell migration were decreased in SteA-expressing cells. • These results contribute to understand the role of SteA during infections. - Abstract: Salmonella enterica is a Gram-negative bacterium that causes gastroenteritis, bacteremia and typhoid fever in several animal species including humans. Its virulence is greatly dependent on two type III secretion systems, encoded in pathogenicity islands 1 and 2. These systems translocate proteins called effectors into eukaryotic host cell. Effectors interfere with host signal transduction pathways to allow the internalization of pathogens and their survival and proliferation inside vacuoles. SteA is one of the few Salmonella effectors that are substrates of both type III secretion systems. Here, we used gene arrays and bioinformatics analysis to study the genetic response of human epithelial cells to SteA. We found that constitutive synthesis of SteA in HeLa cells leads to induction of genes related to extracellular matrix organization and regulation of cell proliferation and serine/threonine kinase signaling pathways. SteA also causes repression of genes related to immune processes and regulation of purine nucleotide synthesis and pathway-restricted SMAD protein phosphorylation. In addition, a cell biology approach revealed that epithelial cells expressing steA show altered cell morphology, and decreased cytotoxicity, cell–cell adhesion and migration.

  10. Space-based multifunctional end effector systems functional requirements and proposed designs

    Science.gov (United States)

    Mishkin, A. H.; Jau, B. M.

    1988-01-01

    The end effector is an essential element of teleoperator and telerobot systems to be employed in space in the next decade. The report defines functional requirements for end effector systems to perform operations that are currently only feasible through Extra-Vehicular Activity (EVA). Specific tasks and functions that the end effectors must be capable of performing are delineated. Required capabilities for forces and torques, clearances, compliance, and sensing are described, using current EVA requirements as guidelines where feasible. The implications of these functional requirements on the elements of potential end effector systems are discussed. The systems issues that must be considered in the design of space-based manipulator systems are identified; including impacts on subsystems tightly coupled to the end effector, i.e., control station, information processing, manipulator arm, tool and equipment stowage. Possible end effector designs are divided into three categories: single degree-of-freedom end effectors, multiple degree of freedom end effectors, and anthropomorphic hands. Specific design alternatives are suggested and analyzed within the individual categories. Two evaluations are performed: the first considers how well the individual end effectors could substitute for EVA; the second compares how manipulator systems composed of the top performers from the first evaluation would improve the space shuttle Remote Manipulator System (RMS) capabilities. The analysis concludes that the anthropomorphic hand is best-suited for EVA tasks. A left- and right-handed anthropomorphic manipulator arm configuration is suggested as appropriate to be affixed to the RMS, but could also be used as part of the Smart Front End for the Orbital Maneuvering Vehicle (OMV). The technical feasibility of the anthropomorphic hand and its control are demonstrated. An evolutionary development approach is proposed and approximate scheduling provided for implementing the suggested

  11. Primary Sjogrens syndrome, with lymphocytic interticial pneumonia and cystic pulmonary disease

    International Nuclear Information System (INIS)

    Vallejo, Jimi Mejia; Bayona, Jorge Carrillo; Iglesias Gamarra, Antonio; Rondon Federico Sanchez Contreras Alvaro, Restrepo Jose Felix

    2007-01-01

    The primary Sjogrens syndrome (PSS) is a chronic autoimmune exocrinopathy characterized by lymphocytic infiltration of glandular and extraglanduIar tissue, the lung involvement is heterogeneous; the aim of this study is report the first case in Colombia of PSS with Iymphocytic intersticiaI pneumonia and cystic pulmonary disease discuss differential diagnosis and the initial diagnostic and therapeutic work up

  12. Identification and Characterisation CRN Effectors in Phytophthora capsici Shows Modularity and Functional Diversity.

    Directory of Open Access Journals (Sweden)

    Remco Stam

    Full Text Available Phytophthora species secrete a large array of effectors during infection of their host plants. The Crinkler (CRN gene family encodes a ubiquitous but understudied class of effectors with possible but as of yet unknown roles in infection. To appreciate CRN effector function in Phytophthora, we devised a simple Crn gene identification and annotation pipeline to improve effector prediction rates. We predicted 84 full-length CRN coding genes and assessed CRN effector domain diversity in sequenced Oomycete genomes. These analyses revealed evidence of CRN domain innovation in Phytophthora and expansion in the Peronosporales. We performed gene expression analyses to validate and define two classes of CRN effectors, each possibly contributing to infection at different stages. CRN localisation studies revealed that P. capsici CRN effector domains target the nucleus and accumulate in specific sub-nuclear compartments. Phenotypic analyses showed that few CRN domains induce necrosis when expressed in planta and that one cell death inducing effector, enhances P. capsici virulence on Nicotiana benthamiana. These results suggest that the CRN protein family form an important class of intracellular effectors that target the host nucleus during infection. These results combined with domain expansion in hemi-biotrophic and necrotrophic pathogens, suggests specific contributions to pathogen lifestyles. This work will bolster CRN identification efforts in other sequenced oomycete species and set the stage for future functional studies towards understanding CRN effector functions.

  13. Effect of Vibrio cholerae neuraminidase on the mitogen response of T lymphocytes. I. Enhancement of macrophage T-lymphocyte cooperation in concanavalin-A-induced lymphocyte activation.

    Science.gov (United States)

    Knop, J

    1980-12-01

    Vibrio cholerae neuraminidase (VCN) enhances the immune response of lymphocytes in various systems, such as antigen- and mitogen-induced blastogenesis, mixed lymphocyte culture (MLC) and tumor-cell response. We used macrophage-depleted and reconstituted murine lymph-node T-cells to investigate the effect of VCN on macrophage-T-lymphocyte co-operation in Con-A-induced lymphocyte activation. In unfractionated lymph-node cells VCN enhanced the Con-A-induced lymphocyte activation as measured by 3H-thymidine (3H-dThd) incorporation. Removing macrophages from the cells resulted in a significantly diminished response. In addition the enhancing effect of VCN was greatly reduced. Reconstitution of the lymphocyte cultures with macrophages in increasing numbers and from various sources rstored the lymphocyte response and the enhancing effect of VCN. VCN proved to be most efficient in cultures reconstituted with normal peritoneal macrophages. Some effect was also observed using bone-marrow-derived (BM) macrophages. However, higher numbers of normal PE macrophages in the presence of VCN inhibited lymphocyte activation, and inhibition by thioglycollate-broth-induced macrophages was considerably increased by VCN. These results suggest that VCN acts by increasing the efficiency of macrophage-T lymphocyte interaction.

  14. C-reactive protein bearing cells are a subpopulation of natural killer cell precursors

    International Nuclear Information System (INIS)

    Baum, L.L.; Krueger, N.X.

    1986-01-01

    Cell surface C-reactive protein (S-CRP) is expressed on the surface membrane of a small percentage of lymphocytes. Anti-CRP inhibits natural killer (NK) function. Since NK effectors are heterogeneous, they suspected that the cells expressing S-CRP (CRP + ) might respond differently to stimulation than the NK effectors lacking S-CRP (CRP - ). Methods were developed to separate CRP + and CRP - lymphocytes and their functional responses were examined and compared. These techniques are dependent upon the binding of CRP to its ligands, C-polysaccharide (CPS) or Phosphocholine (PC). The first method involves rosette formation with CPS coupled autologous red blood cells; the second method utilizes the binding of CRP + lymphocytes to PC-sepharose. Lymphocytes separated using either of these techniques yield similar results. CRP - lymphocytes respond to 3 day incubation with PHA or Il-2 by producing effectors which kill 51 Cr labeled K562 tumor cells, CRP + precursors do not. CRP + lymphocytes respond to a 5 day incubation with inactivated K562 by producing effectors which kill K562; CRP - precursors do not. NK functional activity of both is increased by incubation with interferon. This ability to respond differently to stimulation suggests that CRP + and CRP - cells are functionally distinct

  15. Subpopulations of lymphocytes and their bearing on the radiation dose-response of the human lymphocyte (cell survival, mitogenic stimulation and chromosome aberration frequency)

    International Nuclear Information System (INIS)

    Schwartz, J.L.

    1979-01-01

    To determine whether in the lymphocyte the frequency of chromosome aberrations might be influenced by a differential radiation response of the varying types of cells, as well as interactions among them, subpopulations were separated on the basis of differences in cell surface receptors. The subpopulations, namely, T and B lymphocytes and three T subsets, T-M, T-G, T-null, were found to differ in radiosensitivity as measured by survival in culture and mitotic index after PHA stimulation. All the populations studied are represented to varying degrees among the mitotic cells of unirradiated samples 48 hours after PHA stimulation. At increasing doses of 6 Co gamma rays (50, 100, 250, 500 rads), however, their proportions change both as a direct result of irradiation, such as cell killing, and as an indirect effect, such as the reduction in suppressor cell action

  16. Differential effect of gamma-irradiated and heat-treated lymphocytes on T cell activation, and interleukin-2 and interleukin-3 release in the human mixed lymphocyte reaction

    International Nuclear Information System (INIS)

    Loertscher, R.; Abbud-Filho, M.; Leichtman, A.B.; Ythier, A.A.; Williams, J.M.; Carpenter, C.B.; Strom, T.B.

    1987-01-01

    Heat-inactivated (45 degrees C/1 hr) lymphocytes selectively activate suppressor T cells in the mixed lymphocyte reaction (MLR), while no significant proliferation and cytotoxic T lymphocyte activation can be detected. It is not well understood why hyperthermic treatment abolishes the stimulatory capacity of lymphocytes since HLA-DR molecules remain detectable immediately following heat exposure. In order to further characterize the requirements for Ts activation we studied the effects of hyperthermic treatment on cellular protein and DNA synthesis and cell surface protein expression in proliferating T and B cells; interleukin (IL)-1, IL-2, and IL-3 release following allogeneic stimulation with heat treated cells (HMLR); and IL-2 receptor expression as an indicator of T cell activation in the HMLR. Hyperthermic treatment reduced cellular protein synthesis as estimated by 14 C-leucine uptake to about 15%, and DNA synthesis ( 3 H-thymidine incorporation) to about 5% of untreated control cells. In contrast to y-irradiated cells, viability of heated cells rapidly declined within the first 24 hr. Hyperthermic treatment doubled binding of mouse immunoglobulin paralleled by an increased expression of IL-2 and transferrin receptors, while expression of HLA-DR and 4F2 proteins appeared unchanged. Stimulation with heated cells triggered the release of IL-1- and an IL-3-like bioactivity but did not induce IL-2 synthesis and/or release, thus explaining the lack of proliferation in the HMLR. Addition of exogenous IL-2 but not IL-1 restored HMLR proliferation. A comparison of allostimulation with y-irradiated and heat-treated cells revealed that significantly fewer T cells were induced to express IL-2 receptors at day 3 (14% vs. 8%, P less than 0.001) and at day 6 (42% vs. 21%, P less than 0.05) with heat-inactivated stimulators

  17. Evaluation of secretion prediction highlights differing approaches needed for oomycete and fungal effectors

    Directory of Open Access Journals (Sweden)

    Jana eSperschneider

    2015-12-01

    Full Text Available The steadily increasing number of sequenced fungal and oomycete genomes has enabled detailed studies of how these eukaryotic microbes infect plants and cause devastating losses in food crops. During infection, fungal and oomycete pathogens secrete effector molecules which manipulate host plant cell processes to the pathogen’s advantage. Proteinaceous effectors are synthesised intracellularly and must be externalised to interact with host cells. Computational prediction of secreted proteins from genomic sequences is an important technique to narrow down the candidate effector repertoire for subsequent experimental validation. In this study, we benchmark secretion prediction tools on experimentally validated fungal and oomycete effectors. We observe that for a set of fungal SwissProt protein sequences, SignalP 4 and the neural network predictors of SignalP 3 (D-score and SignalP 2 perform best. For effector prediction in particular, the use of a sensitive method can be desirable to obtain the most complete candidate effector set. We show that the neural network predictors of SignalP 2 and 3, as well as TargetP were the most sensitive tools for fungal effector secretion prediction, whereas the hidden Markov model predictors of SignalP 2 and 3 were the most sensitive tools for oomycete effectors. Thus, previous versions of SignalP retain value for oomycete effector prediction, as the current version, SignalP 4, was unable to reliably predict the signal peptide of the oomycete Crinkler effectors in the test set. Our assessment of subcellular localisation predictors shows that cytoplasmic effectors are often predicted as not extracellular. This limits the reliability of secretion predictions that depend on these tools. We present our assessment with a view to informing future pathogenomics studies and suggest revised pipelines for secretion prediction to obtain optimal effector predictions in fungi and oomycetes.

  18. Effector profiles distinguish formae speciales of Fusarium oxysporum.

    Science.gov (United States)

    van Dam, Peter; Fokkens, Like; Schmidt, Sarah M; Linmans, Jasper H J; Kistler, H Corby; Ma, Li-Jun; Rep, Martijn

    2016-11-01

    Formae speciales (ff.spp.) of the fungus Fusarium oxysporum are often polyphyletic within the species complex, making it impossible to identify them on the basis of conserved genes. However, sequences that determine host-specific pathogenicity may be expected to be similar between strains within the same forma specialis. Whole genome sequencing was performed on strains from five different ff.spp. (cucumerinum, niveum, melonis, radicis-cucumerinum and lycopersici). In each genome, genes for putative effectors were identified based on small size, secretion signal, and vicinity to a "miniature impala" transposable element. The candidate effector genes of all genomes were collected and the presence/absence patterns in each individual genome were clustered. Members of the same forma specialis turned out to group together, with cucurbit-infecting strains forming a supercluster separate from other ff.spp. Moreover, strains from different clonal lineages within the same forma specialis harbour identical effector gene sequences, supporting horizontal transfer of genetic material. These data offer new insight into the genetic basis of host specificity in the F. oxysporum species complex and show that (putative) effectors can be used to predict host specificity in F. oxysporum. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

  19. Effector-triggered immunity: from pathogen perception to robust defense.

    Science.gov (United States)

    Cui, Haitao; Tsuda, Kenichi; Parker, Jane E

    2015-01-01

    In plant innate immunity, individual cells have the capacity to sense and respond to pathogen attack. Intracellular recognition mechanisms have evolved to intercept perturbations by pathogen virulence factors (effectors) early in host infection and convert it to rapid defense. One key to resistance success is a polymorphic family of intracellular nucleotide-binding/leucine-rich-repeat (NLR) receptors that detect effector interference in different parts of the cell. Effector-activated NLRs connect, in various ways, to a conserved basal resistance network in order to transcriptionally boost defense programs. Effector-triggered immunity displays remarkable robustness against pathogen disturbance, in part by employing compensatory mechanisms within the defense network. Also, the mobility of some NLRs and coordination of resistance pathways across cell compartments provides flexibility to fine-tune immune outputs. Furthermore, a number of NLRs function close to the nuclear chromatin by balancing actions of defense-repressing and defense-activating transcription factors to program cells dynamically for effective disease resistance.

  20. Curcumin and Cholecalciferol in Treating Patients With Previously Untreated Stage 0-II Chronic Lymphocytic Leukemia or Small Lymphocytic Lymphoma

    Science.gov (United States)

    2018-01-26

    Contiguous Stage II Small Lymphocytic Lymphoma; Noncontiguous Stage II Small Lymphocytic Lymphoma; Stage 0 Chronic Lymphocytic Leukemia; Stage I Chronic Lymphocytic Leukemia; Stage I Small Lymphocytic Lymphoma; Stage II Chronic Lymphocytic Leukemia

  1. Cytotoxic T lymphocyte responses by chimeric thymocytes. Self-recognition is determined early in T cell development

    International Nuclear Information System (INIS)

    Kruisbeek, A.M.; Hodes, R.J.; Singer, A.

    1981-01-01

    In this study the cytotoxic T lymphocyte (CTL) recognition pattern of thymocytes from recently reconstituted parent leads to F1 and F1 leads to parent radiation bone marrow chimeras was investigated. Chimeric thymocytes were entirely of donor origin approximately 4 weeks after irradiation and reconstitution but were not capable of autonomously generating either alloreactive or trinitrophenyl (TNP)-modified-self-reactive CTL responses. These experiments demonstrte that even at the earliest time CTL effectors of donor origin from the thymuses of chimeras can be studied, their self-receptor repertoire has already been restricted to recognition of host MHC determinants. These results support the cocept that the host environment influences the self-recognition capacity of T cells at the pre- or intrathymic stage of differentation

  2. Discrimination of human cytotoxic lymphocytes from regulatory and B-lymphocytes by orthogonal light scattering

    NARCIS (Netherlands)

    Terstappen, Leonardus Wendelinus Mathias Marie; de Grooth, B.G.; ten Napel, C.H.H.; van Berkel, W.; Greve, Jan

    1986-01-01

    Light scattering properties of human lymphocyte subpopulations selected by immunofluorescence were studied with a flow cytometer. Regulatory and B-lymphocytes showed a low orthogonal light scatter signal, whereas cytotoxic lymphocytes identified with leu-7, leu-11 and leu-15 revealed a large

  3. Quetiapine, an atypical antipsychotic, is protective against autoimmune-mediated demyelination by inhibiting effector T cell proliferation.

    Directory of Open Access Journals (Sweden)

    Feng Mei

    Full Text Available Quetiapine (Que, a commonly used atypical antipsychotic drug (APD, can prevent myelin from breakdown without immune attack. Multiple sclerosis (MS, an autoimmune reactive inflammation demyelinating disease, is triggered by activated myelin-specific T lymphocytes (T cells. In this study, we investigated the potential efficacy of Que as an immune-modulating therapeutic agent for experimental autoimmune encephalomyelitis (EAE, a mouse model for MS. Que treatment was initiated on the onset of MOG(35-55 peptide induced EAE mice and the efficacy of Que on modulating the immune response was determined by Flow Cytometry through analyzing CD4(+/CD8(+ populations and the proliferation of effector T cells (CD4(+CD25(- in peripheral immune organs. Our results show that Que dramatically attenuates the severity of EAE symptoms. Que treatment decreases the extent of CD4(+/CD8(+ T cell infiltration into the spinal cord and suppresses local glial activation, thereby diminishing the loss of mature oligodendrocytes and myelin breakdown in the spinal cord of EAE mice. Our results further demonstrate that Que treatment decreases the CD4(+/CD8(+ T cell populations in lymph nodes and spleens of EAE mice and inhibits either MOG(35-55 or anti-CD3 induced proliferation as well as IL-2 production of effector T cells (CD4(+CD25(- isolated from EAE mice spleen. Together, these findings suggest that Que displays an immune-modulating role during the course of EAE, and thus may be a promising candidate for treatment of MS.

  4. Type VI secretion system MIX-effectors carry both antibacterial and anti-eukaryotic activities.

    Science.gov (United States)

    Ray, Ann; Schwartz, Nika; de Souza Santos, Marcela; Zhang, Junmei; Orth, Kim; Salomon, Dor

    2017-11-01

    Most type VI secretion systems (T6SSs) described to date are protein delivery apparatuses that mediate bactericidal activities. Several T6SSs were also reported to mediate virulence activities, although only few anti-eukaryotic effectors have been described. Here, we identify three T6SSs in the marine bacterium Vibrio proteolyticus and show that T6SS1 mediates bactericidal activities under warm marine-like conditions. Using comparative proteomics, we find nine potential T6SS1 effectors, five of which belong to the polymorphic MIX-effector class. Remarkably, in addition to six predicted bactericidal effectors, the T6SS1 secretome includes three putative anti-eukaryotic effectors. One of these is a MIX-effector containing a cytotoxic necrotizing factor 1 domain. We demonstrate that T6SS1 can use this MIX-effector to target phagocytic cells, resulting in morphological changes and actin cytoskeleton rearrangements. In conclusion, the V. proteolyticus T6SS1, a system homologous to one found in pathogenic vibrios, uses a suite of polymorphic effectors that target both bacteria and eukaryotic neighbors. © 2017 The Authors. Published under the terms of the CC BY 4.0 license.

  5. Convergent Evolution of Pathogen Effectors toward Reactive Oxygen Species Signaling Networks in Plants.

    Science.gov (United States)

    Jwa, Nam-Soo; Hwang, Byung Kook

    2017-01-01

    Microbial pathogens have evolved protein effectors to promote virulence and cause disease in host plants. Pathogen effectors delivered into plant cells suppress plant immune responses and modulate host metabolism to support the infection processes of pathogens. Reactive oxygen species (ROS) act as cellular signaling molecules to trigger plant immune responses, such as pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) and effector-triggered immunity. In this review, we discuss recent insights into the molecular functions of pathogen effectors that target multiple steps in the ROS signaling pathway in plants. The perception of PAMPs by pattern recognition receptors leads to the rapid and strong production of ROS through activation of NADPH oxidase Respiratory Burst Oxidase Homologs (RBOHs) as well as peroxidases. Specific pathogen effectors directly or indirectly interact with plant nucleotide-binding leucine-rich repeat receptors to induce ROS production and the hypersensitive response in plant cells. By contrast, virulent pathogens possess effectors capable of suppressing plant ROS bursts in different ways during infection. PAMP-triggered ROS bursts are suppressed by pathogen effectors that target mitogen-activated protein kinase cascades. Moreover, pathogen effectors target vesicle trafficking or metabolic priming, leading to the suppression of ROS production. Secreted pathogen effectors block the metabolic coenzyme NADP-malic enzyme, inhibiting the transfer of electrons to the NADPH oxidases (RBOHs) responsible for ROS generation. Collectively, pathogen effectors may have evolved to converge on a common host protein network to suppress the common plant immune system, including the ROS burst and cell death response in plants.

  6. Convergent Evolution of Pathogen Effectors toward Reactive Oxygen Species Signaling Networks in Plants

    Directory of Open Access Journals (Sweden)

    Nam-Soo Jwa

    2017-09-01

    Full Text Available Microbial pathogens have evolved protein effectors to promote virulence and cause disease in host plants. Pathogen effectors delivered into plant cells suppress plant immune responses and modulate host metabolism to support the infection processes of pathogens. Reactive oxygen species (ROS act as cellular signaling molecules to trigger plant immune responses, such as pathogen-associated molecular pattern (PAMP-triggered immunity (PTI and effector-triggered immunity. In this review, we discuss recent insights into the molecular functions of pathogen effectors that target multiple steps in the ROS signaling pathway in plants. The perception of PAMPs by pattern recognition receptors leads to the rapid and strong production of ROS through activation of NADPH oxidase Respiratory Burst Oxidase Homologs (RBOHs as well as peroxidases. Specific pathogen effectors directly or indirectly interact with plant nucleotide-binding leucine-rich repeat receptors to induce ROS production and the hypersensitive response in plant cells. By contrast, virulent pathogens possess effectors capable of suppressing plant ROS bursts in different ways during infection. PAMP-triggered ROS bursts are suppressed by pathogen effectors that target mitogen-activated protein kinase cascades. Moreover, pathogen effectors target vesicle trafficking or metabolic priming, leading to the suppression of ROS production. Secreted pathogen effectors block the metabolic coenzyme NADP-malic enzyme, inhibiting the transfer of electrons to the NADPH oxidases (RBOHs responsible for ROS generation. Collectively, pathogen effectors may have evolved to converge on a common host protein network to suppress the common plant immune system, including the ROS burst and cell death response in plants.

  7. Hypoxia Enhances Immunosuppression by Inhibiting CD4+ Effector T Cell Function and Promoting Treg Activity

    Directory of Open Access Journals (Sweden)

    Astrid M. Westendorf

    2017-03-01

    Full Text Available Background/Aims: Hypoxia occurs in many pathological conditions, including inflammation and cancer. Within this context, hypoxia was shown to inhibit but also to promote T cell responses. Due to this controversial function, we aimed to explore whether an insufficient anti-tumour response during colitis-associated colon cancer could be ascribed to a hypoxic microenvironment. Methods: Colitis-associated colon cancer was induced in wildtype mice, and hypoxia as well as T cell immunity were analysed in the colonic tumour tissues. In addition, CD4+ effector T cells and regulatory T cells were cultured under normoxic and hypoxic conditions and examined regarding their phenotype and function. Results: We observed severe hypoxia in the colon of mice suffering from colitis-associated colon cancer that was accompanied by a reduced differentiation of CD4+ effector T cells and an enhanced number and suppressive activity of regulatory T cells. Complementary ex vivo and in vitro studies revealed that T cell stimulation under hypoxic conditions inhibited the differentiation, proliferation and IFN-γ production of TH1 cells and enhanced the suppressive capacity of regulatory T cells. Moreover, we identified an active role for HIF-1α in the modulation of CD4+ T cell functions under hypoxic conditions. Conclusion: Our data indicate that oxygen availability can function as a local modulator of CD4+ T cell responses and thus influences tumour immune surveillance in inflammation-associated colon cancer.

  8. Expression of K2P5.1 potassium channels on CD4+ T lymphocytes correlates with disease activity in rheumatoid arthritis patients.

    Science.gov (United States)

    Bittner, Stefan; Bobak, Nicole; Feuchtenberger, Martin; Herrmann, Alexander M; Göbel, Kerstin; Kinne, Raimund W; Hansen, Anker J; Budde, Thomas; Kleinschnitz, Christoph; Frey, Oliver; Tony, Hans-Peter; Wiendl, Heinz; Meuth, Sven G

    2011-02-11

    CD4+ T cells express K(2P)5.1 (TWIK-related acid-sensitive potassium channel 2 (TASK2); KCNK5), a member of the two-pore domain potassium channel family, which has been shown to influence T cell effector functions. Recently, it was shown that K(2P)5.1 is upregulated upon (autoimmune) T cell stimulation. The aim of this study was to correlate expression levels of K(2P)5.1 on T cells from patients with rheumatoid arthritis (RA) to disease activity in these patients. Expression levels of K(2P)5.1 were measured by RT-PCR in the peripheral blood of 58 patients with RA and correlated with disease activity parameters (C-reactive protein levels, erythrocyte sedimentation rates, disease activity score (DAS28) scores). Twenty patients undergoing therapy change were followed-up for six months. Additionally, synovial fluid and synovial biopsies were investigated for T lymphocytes expressing K(2P)5.1. K(2P)5.1 expression levels in CD4+ T cells show a strong correlation to DAS28 scores in RA patients. Similar correlations were found for serological inflammatory parameters (erythrocyte sedimentation rate, C-reactive protein). In addition, K(2P)5.1 expression levels of synovial fluid-derived T cells are higher compared to peripheral blood T cells. Prospective data in individual patients show a parallel behaviour of K(2P)5.1 expression to disease activity parameters during a longitudinal follow-up for six months. Disease activity in RA patients correlates strongly with K(2P)5.1 expression levels in CD4+ T lymphocytes in the peripheral blood in cross-sectional as well as in longitudinal observations. Further studies are needed to investigate the exact pathophysiological mechanisms and to evaluate the possible use of K(2P)5.1 as a potential biomarker for disease activity and differential diagnosis.

  9. Capacity of tumor necrosis factor to augment lymphocyte-mediated tumor cell lysis of malignant mesothelioma

    International Nuclear Information System (INIS)

    Bowman, R.V.; Manning, L.S.; Davis, M.R.; Robinson, B.W.

    1991-01-01

    Recombinant human tumor necrosis factor (rHuTNF) was evaluated both for direct anti-tumor action against human malignant mesothelioma and for its capacity to augment the generation and lytic phases of lymphocyte-mediated cytotoxicity against this tumor. rHuTNF was directly toxic by MTT assay to one of two mesothelioma cell lines evaluated, but had no effect on susceptibility to subsequent lymphocyte-mediated lysis of either line. TNF alone was incapable of generating anti-mesothelioma lymphokine-activated killer cell (LAK) activity. Furthermore, it did not augment the degree or LAK activity produced by submaximal interleukin-2 (IL-2) concentrations nor did it augment lysis of mesothelioma cells by natural killer (NK) or LAK effector cells during the 4-hr 51chromium release cytolytic reaction. The studies also suggest that mesothelioma targets are less responsive to TNF plus submaximal IL-2 concentrations than the standard LAK sensitive target Daudi, raising the possibility that intermediate LAK sensitive tumors such as mesothelioma may require separate and specific evaluation in immunomodulation studies. This in vitro study indicates that use of low-dose rHuTNF and IL-2 is unlikely to be an effective substitute for high-dose IL-2 in generation and maintenance of LAK activity in adoptive immunotherapy for mesothelioma

  10. Characterization of the largest effector gene cluster of Ustilago maydis.

    Directory of Open Access Journals (Sweden)

    Thomas Brefort

    2014-07-01

    Full Text Available In the genome of the biotrophic plant pathogen Ustilago maydis, many of the genes coding for secreted protein effectors modulating virulence are arranged in gene clusters. The vast majority of these genes encode novel proteins whose expression is coupled to plant colonization. The largest of these gene clusters, cluster 19A, encodes 24 secreted effectors. Deletion of the entire cluster results in severe attenuation of virulence. Here we present the functional analysis of this genomic region. We show that a 19A deletion mutant behaves like an endophyte, i.e. is still able to colonize plants and complete the infection cycle. However, tumors, the most conspicuous symptoms of maize smut disease, are only rarely formed and fungal biomass in infected tissue is significantly reduced. The generation and analysis of strains carrying sub-deletions identified several genes significantly contributing to tumor formation after seedling infection. Another of the effectors could be linked specifically to anthocyanin induction in the infected tissue. As the individual contributions of these genes to tumor formation were small, we studied the response of maize plants to the whole cluster mutant as well as to several individual mutants by array analysis. This revealed distinct plant responses, demonstrating that the respective effectors have discrete plant targets. We propose that the analysis of plant responses to effector mutant strains that lack a strong virulence phenotype may be a general way to visualize differences in effector function.

  11. Effector candidates in the secretome of Piriformospora indica, a ubiquitous plant-associated fungus

    Directory of Open Access Journals (Sweden)

    Maryam eRafiqi

    2013-07-01

    Full Text Available One of the emerging systems in plant-microbe interaction is the study of proteins, referred to as effectors, secreted by microbes in order to modulate host cells function and structure and to promote microbial growth on plant tissue. Current knowledge on fungal effectors derives mainly from biotrophic and hemibiotrophic plant fungal pathogens that have a limited host range. Here, we focus on effectors of Piriformospora indica, a soil borne endophyte forming intimate associations with roots of a wide range of plant species. Complete genome sequencing provides an opportunity to investigate the role of effectors during the interaction of this mutualistic fungus with plants. We describe in silico analyses to predict effectors of P. indica and we explore effector features considered here to mine a high priority protein list for functional analysis.

  12. Progranulin Inhibits Human T Lymphocyte Proliferation by Inducing the Formation of Regulatory T Lymphocytes

    Directory of Open Access Journals (Sweden)

    Kyu Hwan Kwack

    2017-01-01

    Full Text Available We have examined the effect of progranulin (PGRN on human T cell proliferation and its underlying mechanism. We show that PGRN inhibits the PHA-induced multiplication of T lymphocytes. It increases the number of iTregs when T lymphocytes are activated by PHA but does not do so in the absence of PHA. PGRN-mediated inhibition of T lymphocyte proliferation, as well as the induction of iTregs, was completely reversed by a TGF-β inhibitor or a Treg inhibitor. PGRN induced TGF-β secretion in the presence of PHA whereas it did not in the absence of PHA. Our findings indicate that PGRN suppresses T lymphocyte proliferation by enhancing the formation of iTregs from activated T lymphocytes in response to TGF-β.

  13. Flow cytometric analysis of lymphocytes and lymphocyte subpopulations in induced sputum from patients with asthma

    Directory of Open Access Journals (Sweden)

    Yutaro Shiota

    2000-01-01

    Full Text Available Study objectives were to compare the numbers of lymphocytes and lymphocyte subpopulations in induced sputum from asthmatic patients and from healthy subjects, and to determine the effect of inhaled anti-asthmatic steroid therapy on these cell numbers. Hypertonic saline inhalation was used to non-invasively induce sputum samples in 34 patients with bronchial asthma and 21 healthy subjects. The sputum samples were reduced with dithioerythritol and absolute numbers of lymphocytes and lymphocyte subpopulations were assessed by direct immunofluorescence and flow cytometry. To assess the effect of beclomethasone dipropionate (BDP on induced sputum, numbers of lymphocytes and lymphocyte subpopulations in sputum also were evaluated after 4 weeks of BDP inhalation treatment in seven asthmatic patients. An adequate sample was obtained in 85.3% of patients with asthma and in 79.2% of the healthy subjects. Induced sputum from patients with asthma had increased numbers of lymphocytes (P = 0.009; CD4+ cells (P = 0.044; CD4+ cells-bearing interleukin-2 receptor (CD25; P = 0.016; and CD4+ cells bearing human histocompatibility leukocyte antigen (HLA-DR (P = 0.033. CD8+ cells were not increased in asthmatic patients. In patients treated with inhaled steroids, numbers of lymphocytes, CD4+ cells, CD25-bearing CD4+ cells and HLA-DR-bearing CD4+ cells in sputum decreased from pretreatment numbers (P = 0.016, 0.002, 0.003 and 0.002, respectively. Analysis of lymphocytes in induced sputum by flow cytometry is useful in assessing bronchial inflammation, and activated CD4+ lymphocytes may play a key role in the pathogenesis of airway inflammation in bronchial asthma.

  14. Epigenomic Views of Innate Lymphoid Cells.

    Science.gov (United States)

    Sciumè, Giuseppe; Shih, Han-Yu; Mikami, Yohei; O'Shea, John J

    2017-01-01

    The discovery of innate lymphoid cells (ILCs) with selective production of cytokines typically attributed to subsets of T helper cells forces immunologists to reassess the mechanisms by which selective effector functions arise. The parallelism between ILCs and T cells extends beyond these two cell types and comprises other innate-like T lymphocytes. Beyond the recognition of specialized effector functionalities in diverse lymphocytes, features typical of T cells, such as plasticity and memory, are also relevant for innate lymphocytes. Herein, we review what we have learned in terms of the molecular mechanisms underlying these shared functions, focusing on insights provided by next generation sequencing technologies. We review data on the role of lineage-defining- and signal-dependent transcription factors (TFs). ILC regulomes emerge developmentally whereas the much of the open chromatin regions of T cells are generated acutely, in an activation-dependent manner. And yet, these regions of open chromatin in T cells and ILCs have remarkable overlaps, suggesting that though accessibility is acquired by distinct modes, the end result is that convergent signaling pathways may be involved. Although much is left to be learned, substantial progress has been made in understanding how TFs and epigenomic status contribute to ILC biology in terms of differentiation, specification, and plasticity.

  15. Broad T-cell receptor repertoire in T-lymphocytes derived from human induced pluripotent stem cells.

    Directory of Open Access Journals (Sweden)

    Chia-Wei Chang

    Full Text Available Human induced pluripotent stem cells (hiPSCs have enormous potential for the treatment of inherited and acquired disorders. Recently, antigen-specific T lymphocytes derived from hiPSCs have been reported. However, T lymphocyte populations with broad T cell receptor (TCR diversity have not been generated. We report that hiPSCs derived from skin biopsy are capable of producing T lymphocyte populations with a broad TCR repertoire. In vitro T cell differentiation follows a similar developmental program as observed in vivo, indicated by sequential expression of CD7, intracellular CD3 and surface CD3. The γδ TCR locus is rearranged first and is followed by rearrangement of the αβ locus. Both γδ and αβ T cells display a diverse TCR repertoire. Upon activation, the cells express CD25, CD69, cytokines (TNF-α, IFN-γ, IL-2 and cytolytic proteins (Perforin and Granzyme-B. These results suggest that most, if not all, mechanisms required to generate functional T cells with a broad TCR repertoire are intact in our in vitro differentiation protocol. These data provide a foundation for production of patient-specific T cells for the treatment of acquired or inherited immune disorders and for cancer immunotherapy.

  16. Target selection biases from recent experience transfer across effectors.

    Science.gov (United States)

    Moher, Jeff; Song, Joo-Hyun

    2016-02-01

    Target selection is often biased by an observer's recent experiences. However, not much is known about whether these selection biases influence behavior across different effectors. For example, does looking at a red object make it easier to subsequently reach towards another red object? In the current study, we asked observers to find the uniquely colored target object on each trial. Randomly intermixed pre-trial cues indicated the mode of action: either an eye movement or a visually guided reach movement to the target. In Experiment 1, we found that priming of popout, reflected in faster responses following repetition of the target color on consecutive trials, occurred regardless of whether the effector was repeated from the previous trial or not. In Experiment 2, we examined whether an inhibitory selection bias away from a feature could transfer across effectors. While priming of popout reflects both enhancement of the repeated target features and suppression of the repeated distractor features, the distractor previewing effect isolates a purely inhibitory component of target selection in which a previewed color is presented in a homogenous display and subsequently inhibited. Much like priming of popout, intertrial suppression biases in the distractor previewing effect transferred across effectors. Together, these results suggest that biases for target selection driven by recent trial history transfer across effectors. This indicates that representations in memory that bias attention towards or away from specific features are largely independent from their associated actions.

  17. Identification of Anaplasma marginale type IV secretion system effector proteins.

    Directory of Open Access Journals (Sweden)

    Svetlana Lockwood

    Full Text Available Anaplasma marginale, an obligate intracellular alphaproteobacterium in the order Rickettsiales, is a tick-borne pathogen and the leading cause of anaplasmosis in cattle worldwide. Complete genome sequencing of A. marginale revealed that it has a type IV secretion system (T4SS. The T4SS is one of seven known types of secretion systems utilized by bacteria, with the type III and IV secretion systems particularly prevalent among pathogenic Gram-negative bacteria. The T4SS is predicted to play an important role in the invasion and pathogenesis of A. marginale by translocating effector proteins across its membrane into eukaryotic target cells. However, T4SS effector proteins have not been identified and tested in the laboratory until now.By combining computational methods with phylogenetic analysis and sequence identity searches, we identified a subset of potential T4SS effectors in A. marginale strain St. Maries and chose six for laboratory testing. Four (AM185, AM470, AM705 [AnkA], and AM1141 of these six proteins were translocated in a T4SS-dependent manner using Legionella pneumophila as a reporter system.The algorithm employed to find T4SS effector proteins in A. marginale identified four such proteins that were verified by laboratory testing. L. pneumophila was shown to work as a model system for A. marginale and thus can be used as a screening tool for A. marginale effector proteins. The first T4SS effector proteins for A. marginale have been identified in this work.

  18. System for exchanging tools and end effectors on a robot

    International Nuclear Information System (INIS)

    Burry, D.B.; Williams, P.M.

    1991-01-01

    A system and method for exchanging tools and end effectors on a robot permits exchange during a programmed task. The exchange mechanism is located off the robot, thus reducing the mass of the robot arm and permitting smaller robots to perform designated tasks. A simple spring/collet mechanism mounted on the robot is used which permits the engagement and disengagement of the tool or end effector without the need for a rotational orientation of the tool to the end effector/collet interface. As the tool changing system is not located on the robot arm no umbilical cords are located on robot. 12 figures

  19. The genome sequence and effector complement of the flax rust pathogen Melampsora lini

    Directory of Open Access Journals (Sweden)

    Adnane eNemri

    2014-03-01

    Full Text Available Rust fungi cause serious yield reductions on crops, including wheat, barley, soybean, coffee, and represent real threats to global food security. Of these fungi, the flax rust pathogen Melampsora lini has been developed extensively over the past 80 years as a model to understand the molecular mechanisms that underpin pathogenesis. During infection, M. lini secretes virulence effectors to promote disease. The number of these effectors, their function and their degree of conservation across rust fungal species is unknown. To assess this, we sequenced and assembled de novo the genome of M. lini isolate CH5 into 21,130 scaffolds spanning 189 Mbp (scaffold N50 of 31 kbp. Global analysis of the DNA sequence revealed that repetitive elements, primarily retrotransposons, make up at least 45% of the genome. Using ab initio predictions, transcriptome data and homology searches, we identified 16,271 putative protein-coding genes. An analysis pipeline was then implemented to predict the effector complement of M. lini and compare it to that of the poplar rust, wheat stem rust and wheat stripe rust pathogens to identify conserved and species-specific effector candidates. Previous knowledge of four cloned M. lini avirulence effector proteins and two basidiomycete effectors was used to optimise parameters of the effector prediction pipeline. Markov clustering based on sequence similarity was performed to group effector candidates from all four rust pathogens. Clusters containing at least one member from M. lini were further analysed and prioritized based on features including expression in isolated haustoria and infected leaf tissue and conservation across rust species. Herein, we describe 200 of 940 clusters that ranked highest on our priority list, representing 725 flax rust candidate effectors. Our findings on this important model rust species provide insight into how effectors of rust fungi are conserved across species and how they may act to promote

  20. The genome sequence and effector complement of the flax rust pathogen Melampsora lini.

    Science.gov (United States)

    Nemri, Adnane; Saunders, Diane G O; Anderson, Claire; Upadhyaya, Narayana M; Win, Joe; Lawrence, Gregory J; Jones, David A; Kamoun, Sophien; Ellis, Jeffrey G; Dodds, Peter N

    2014-01-01

    Rust fungi cause serious yield reductions on crops, including wheat, barley, soybean, coffee, and represent real threats to global food security. Of these fungi, the flax rust pathogen Melampsora lini has been developed most extensively over the past 80 years as a model to understand the molecular mechanisms that underpin pathogenesis. During infection, M. lini secretes virulence effectors to promote disease. The number of these effectors, their function and their degree of conservation across rust fungal species is unknown. To assess this, we sequenced and assembled de novo the genome of M. lini isolate CH5 into 21,130 scaffolds spanning 189 Mbp (scaffold N50 of 31 kbp). Global analysis of the DNA sequence revealed that repetitive elements, primarily retrotransposons, make up at least 45% of the genome. Using ab initio predictions, transcriptome data and homology searches, we identified 16,271 putative protein-coding genes. An analysis pipeline was then implemented to predict the effector complement of M. lini and compare it to that of the poplar rust, wheat stem rust and wheat stripe rust pathogens to identify conserved and species-specific effector candidates. Previous knowledge of four cloned M. lini avirulence effector proteins and two basidiomycete effectors was used to optimize parameters of the effector prediction pipeline. Markov clustering based on sequence similarity was performed to group effector candidates from all four rust pathogens. Clusters containing at least one member from M. lini were further analyzed and prioritized based on features including expression in isolated haustoria and infected leaf tissue and conservation across rust species. Herein, we describe 200 of 940 clusters that ranked highest on our priority list, representing 725 flax rust candidate effectors. Our findings on this important model rust species provide insight into how effectors of rust fungi are conserved across species and how they may act to promote infection on their

  1. Diverse Secreted Effectors Are Required for Salmonella Persistence in a Mouse Infection Model

    Energy Technology Data Exchange (ETDEWEB)

    Kidwai, Afshan S.; Mushamiri, Ivy T.; Niemann, George; Brown, Roslyn N.; Adkins, Joshua N.; Heffron, Fred

    2013-08-12

    Salmonella enterica serovar Typhimurium causes typhoid-like disease in mice and is a model of typhoid fever in humans. One of the hallmarks of typhoid is persistence, the ability of the bacteria to survive in the host weeks after infection. Virulence factors called effectors facilitate this process by direct transfer to the cytoplasm of infected cells thereby subverting cellular processes. Secretion of effectors to the cell cytoplasm takes place through multiple routes, including two separate type III secretion (T3SS) apparati as well as outer membrane vesicles. The two T3SS are encoded on separate pathogenicity islands, SPI-1 and -2, with SPI-1 more strongly associated with the intestinal phase of infection, and SPI-2 with the systemic phase. Both T3SS are required for persistence, but the effectors required have not been systematically evaluated. In this study, mutations in 48 described effectors were tested for persistence. We replaced each effector with a specific DNA barcode sequence by allelic exchange and co-infected with a wild-type reference to calculate the ratio of wild-type parent to mutant at different times after infection. The competitive index (CI) was determined by quantitative PCR in which primers that correspond to the barcode were used for amplification. Mutations in all but seven effectors reduced persistence demonstrating that most effectors were required. One exception was CigR, a recently discovered effector that is widely conserved throughout enteric bacteria. Deletion of cigR increased lethality, suggesting that it may be an anti-virulence factor. The fact that almost all Salmonella effectors are required for persistence argues against redundant functions. This is different from effector repertoires in other intracellular pathogens such as Legionella.

  2. Proliferative kinetics and chromosome damage in trisomy 21 lymphocyte cultures exposed to gamma-rays and bleomycin

    International Nuclear Information System (INIS)

    Morimoto, K.; Kaneko, T.; Iijima, K.; Koizumi, A.

    1984-01-01

    Lymphocytes from patients with Down's syndrome (trisomy 21) have been investigated for cell cycle kinetics, cell proliferation delays, and chromosomal aberrations after exposure to gamma-rays or bleomycin. Analysis by sister chromatid differential staining revealed that trisomy 21 lymphocytes started cell cycling about 5 hr earlier than did normal diploid lymphocytes after phytohemagglutinin stimulation as a whole, but that cycling trisomic and normal cells had the same mean cell cycle times. When exposed to gamma-rays or bleomycin in G0, trisomy 21 lymphocytes showed a 30% or, on average, 50% longer duration of cell turnover times, respectively, than normal cells; only bleomycin-treated trisomic cells had a biphasic dose-response. Frequencies of dicentrics and rings in first-division cells after gamma-ray or bleomycin exposure were twice as high in trisomic cells as in normal cells. The frequency of aberrations decreased by 50% (gamma-ray-exposed) or 65 to 85% (bleomycin-treated) through successive divisions; trisomic cells showed a more marked decline in aberration yields compared to normal cells after bleomycin treatment. These data support the idea that circulating lymphocytes in trisomy 21 patients have a shorter average life span or a younger average age

  3. B and T lymphocytes in man. I. Effect of infant thymic irradiation on the circulating B and T lymphocytes

    International Nuclear Information System (INIS)

    Reddy, M.M.; Goh, K.; Hempelmann, L.H.

    1976-01-01

    B and T lymphocytes were studied in a group of adults whose thymic glands were irradiated in infancy for alleged thymic enlargement. Two independent methods were used to determine the B and T lymphocytes from each peripheral blood specimen: (1) the relative proportion of cells with surface immunoglobulins (B lymphocytes) and cells forming rosettes with sheep erythrocytes (T lymphocytes); and (2) the relative mitogenic response to phytohemagglutinin (T lymphocytes) and to pokeweed mitogen (B lymphocytes). All specimens were coded. The results obtained indicate: (1) a reduction of B and T lymphocytes; and (2) a decreased mitogenic response of lymphocytes to phytohemagglutinin and pokeweed mitogen in this group of patients as compared with the controls. These observations suggest that (1) the effect of irradiation to the thymus gland on lymphocytes is long lasting and (2) both B and T lymphocytes are affected by irradiation to the thymus gland

  4. High-throughput gene expression profiling of memory differentiation in primary human T cells

    Directory of Open Access Journals (Sweden)

    Russell Kate

    2008-08-01

    Full Text Available Abstract Background The differentiation of naive T and B cells into memory lymphocytes is essential for immunity to pathogens. Therapeutic manipulation of this cellular differentiation program could improve vaccine efficacy and the in vitro expansion of memory cells. However, chemical screens to identify compounds that induce memory differentiation have been limited by 1 the lack of reporter-gene or functional assays that can distinguish naive and memory-phenotype T cells at high throughput and 2 a suitable cell-line representative of naive T cells. Results Here, we describe a method for gene-expression based screening that allows primary naive and memory-phenotype lymphocytes to be discriminated based on complex genes signatures corresponding to these differentiation states. We used ligation-mediated amplification and a fluorescent, bead-based detection system to quantify simultaneously 55 transcripts representing naive and memory-phenotype signatures in purified populations of human T cells. The use of a multi-gene panel allowed better resolution than any constituent single gene. The method was precise, correlated well with Affymetrix microarray data, and could be easily scaled up for high-throughput. Conclusion This method provides a generic solution for high-throughput differentiation screens in primary human T cells where no single-gene or functional assay is available. This screening platform will allow the identification of small molecules, genes or soluble factors that direct memory differentiation in naive human lymphocytes.

  5. Immune Cell-Mediated Protection against Vaginal Candidiasis: Evidence for a Major Role of Vaginal CD4+ T Cells and Possible Participation of Other Local Lymphocyte Effectors

    Science.gov (United States)

    Santoni, Giorgio; Boccanera, Maria; Adriani, Daniela; Lucciarini, Roberta; Amantini, Consuelo; Morrone, Stefania; Cassone, Antonio; De Bernardis, Flavia

    2002-01-01

    The protective roles of different lymphocyte subsets were investigated in a rat vaginal candidiasis model by adoptive transfer of vaginal lymphocytes (VL) or sorted, purified CD3+ T cells, CD4+ or CD8+ T cells, or CD3− CD5+ B cells from the vaginas of naïve or immune rats following three rounds of Candida albicans infection. The adoptive transfer of total VL from nonimmune animals did not alter the course of vaginal candidiasis of the recipient rats. In contrast, the animals receiving total VL or CD3+ T cells from immune rats showed a highly significant acceleration of fungus clearance compared with animals which received nonimmune VL. The animals with vaginal CD3− CD5+ B cells transferred from immune rats also had fewer Candida CFU than the controls, but fungal clearance was significantly retarded with respect to the animals administered immune T cells. Sorted, purified CD4+ and CD8+ vaginal T cells from immune rats were also adoptively transferred to naïve animals. Although both populations were seen to accelerate the clearance of the fungus from the vagina, CD4+ T cells were much more effective than CD8+ T cells. Overall, there was no difference between the antifungal effects of immune vaginal CD4+ T cells and those achievable with the transfer of whole, immune VL. Histological observations of the vaginal tissues of rats with adoptively transferred immune T cells demonstrated a remarkable accumulation of lymphocytes in the subepithelial lamina propria and also infiltrating the mucosal epithelium. These results strongly suggest that distinct vaginal lymphocyte subsets participate in the adaptive anti-Candida immunity at the vaginal level, with the vaginal CD4+ T cells probably playing a major role. PMID:12183521

  6. Stochastic Measurement Models for Quantifying Lymphocyte Responses Using Flow Cytometry

    Science.gov (United States)

    Kan, Andrey; Pavlyshyn, Damian; Markham, John F.; Dowling, Mark R.; Heinzel, Susanne; Zhou, Jie H. S.; Marchingo, Julia M.; Hodgkin, Philip D.

    2016-01-01

    Adaptive immune responses are complex dynamic processes whereby B and T cells undergo division and differentiation triggered by pathogenic stimuli. Deregulation of the response can lead to severe consequences for the host organism ranging from immune deficiencies to autoimmunity. Tracking cell division and differentiation by flow cytometry using fluorescent probes is a major method for measuring progression of lymphocyte responses, both in vitro and in vivo. In turn, mathematical modeling of cell numbers derived from such measurements has led to significant biological discoveries, and plays an increasingly important role in lymphocyte research. Fitting an appropriate parameterized model to such data is the goal of these studies but significant challenges are presented by the variability in measurements. This variation results from the sum of experimental noise and intrinsic probabilistic differences in cells and is difficult to characterize analytically. Current model fitting methods adopt different simplifying assumptions to describe the distribution of such measurements and these assumptions have not been tested directly. To help inform the choice and application of appropriate methods of model fitting to such data we studied the errors associated with flow cytometry measurements from a wide variety of experiments. We found that the mean and variance of the noise were related by a power law with an exponent between 1.3 and 1.8 for different datasets. This violated the assumptions inherent to commonly used least squares, linear variance scaling and log-transformation based methods. As a result of these findings we propose a new measurement model that we justify both theoretically, from the maximum entropy standpoint, and empirically using collected data. Our evaluation suggests that the new model can be reliably used for model fitting across a variety of conditions. Our work provides a foundation for modeling measurements in flow cytometry experiments thus

  7. Oxysterols and Their Cellular Effectors

    Directory of Open Access Journals (Sweden)

    Eija Nissilä

    2012-02-01

    Full Text Available Oxysterols are oxidized 27-carbon cholesterol derivatives or by-products of cholesterol biosynthesis, with a spectrum of biologic activities. Several oxysterols have cytotoxic and pro-apoptotic activities, the ability to interfere with the lateral domain organization, and packing of membrane lipids. These properties may account for their suggested roles in the pathology of diseases such as atherosclerosis, age-onset macular degeneration and Alzheimer’s disease. Oxysterols also have the capacity to induce inflammatory responses and play roles in cell differentiation processes. The functions of oxysterols as intermediates in the synthesis of bile acids and steroid hormones, and as readily transportable forms of sterol, are well established. Furthermore, their actions as endogenous regulators of gene expression in lipid metabolism via liver X receptors and the Insig (insulin-induced gene proteins have been investigated in detail. The cytoplasmic oxysterol-binding protein (OSBP homologues form a group of oxysterol/cholesterol sensors that has recently attracted a lot of attention. However, their mode of action is, as yet, poorly understood. Retinoic acid receptor-related orphan receptors (ROR α and γ, and Epstein-Barr virus induced gene 2 (EBI2 have been identified as novel oxysterol receptors, revealing new physiologic oxysterol effector mechanisms in development, metabolism, and immunity, and evoking enhanced interest in these compounds in the field of biomedicine.

  8. The Shigella flexneri OspB effector: an early immunomodulator.

    Science.gov (United States)

    Ambrosi, Cecilia; Pompili, Monica; Scribano, Daniela; Limongi, Dolores; Petrucca, Andrea; Cannavacciuolo, Sonia; Schippa, Serena; Zagaglia, Carlo; Grossi, Milena; Nicoletti, Mauro

    2015-01-01

    Through the action of the type three secretion system (T3SS) Shigella flexneri delivers several effectors into host cells to promote cellular invasion, multiplication and to exploit host-cell signaling pathways to modulate the host innate immune response. Although much progress has been made in the understanding of many type III effectors, the molecular and cellular mechanism of the OspB effector is still poorly characterized. In this study we present new evidence that better elucidates the role of OspB as pro-inflammatory factor at very early stages of infection. Indeed, we demonstrate that, during the first hour of infection, OspB is required for full activation of ERK1/2 and p38 MAPKs and the cytosolic phospholipase A(2) (cPLA(2)). Activation of cPLA(2) ultimately leads to the production and secretion of PMN chemoattractant metabolite(s) uncoupled with release of IL-8. Moreover, we also present evidence that OspB is required for the development of the full and promptly inflammatory reaction characteristic of S. flexneri wild-type infection in vivo. Based on OspB and OspF similarity (both effectors share similar transcription regulation, temporal secretion into host cells and nuclear localization) we hypothesized that OspB and OspF effectors may form a pair aimed at modulating the host cell response throughout the infection process, with opposite effects. A model is presented to illustrate how OspB activity would promote S. flexneri invasion and bacterial dissemination at early critical phases of infection. Copyright © 2014 Elsevier GmbH. All rights reserved.

  9. Yersinia type III effectors perturb host innate immune responses

    Science.gov (United States)

    Pha, Khavong; Navarro, Lorena

    2016-01-01

    The innate immune system is the first line of defense against invading pathogens. Innate immune cells recognize molecular patterns from the pathogen and mount a response to resolve the infection. The production of proinflammatory cytokines and reactive oxygen species, phagocytosis, and induced programmed cell death are processes initiated by innate immune cells in order to combat invading pathogens. However, pathogens have evolved various virulence mechanisms to subvert these responses. One strategy utilized by Gram-negative bacterial pathogens is the deployment of a complex machine termed the type III secretion system (T3SS). The T3SS is composed of a syringe-like needle structure and the effector proteins that are injected directly into a target host cell to disrupt a cellular response. The three human pathogenic Yersinia spp. (Y. pestis, Y. enterocolitica, and Y. pseudotuberculosis) are Gram-negative bacteria that share in common a 70 kb virulence plasmid which encodes the T3SS. Translocation of the Yersinia effector proteins (YopE, YopH, YopT, YopM, YpkA/YopO, and YopP/J) into the target host cell results in disruption of the actin cytoskeleton to inhibit phagocytosis, downregulation of proinflammatory cytokine/chemokine production, and induction of cellular apoptosis of the target cell. Over the past 25 years, studies on the Yersinia effector proteins have unveiled tremendous knowledge of how the effectors enhance Yersinia virulence. Recently, the long awaited crystal structure of YpkA has been solved providing further insights into the activation of the YpkA kinase domain. Multisite autophosphorylation by YpkA to activate its kinase domain was also shown and postulated to serve as a mechanism to bypass regulation by host phosphatases. In addition, novel Yersinia effector protein targets, such as caspase-1, and signaling pathways including activation of the inflammasome were identified. In this review, we summarize the recent discoveries made on Yersinia

  10. Interferon-alpha triggers B cell effector 1 (Be1 commitment.

    Directory of Open Access Journals (Sweden)

    Marie-Ghislaine de Goër de Herve

    Full Text Available B-cells can contribute to the pathogenesis of autoimmune diseases not only through auto-antibody secretion but also via cytokine production. Therapeutic depletion of B-cells influences the functions and maintenance of various T-cell subsets. The mechanisms governing the functional heterogeneity of B-cell subsets as cytokine-producing cells are poorly understood. B-cells can differentiate into two functionally polarized effectors, one (B-effector-1-cells producing a Th-1-like cytokine pattern and the other (Be2 producing a Th-2-like pattern. IL-12 and IFN-γ play a key role in Be1 polarization, but the initial trigger of Be1 commitment is unclear. Type-I-interferons are produced early in the immune response and prime several processes involved in innate and adaptive responses. Here, we report that IFN-α triggers a signaling cascade in resting human naive B-cells, involving STAT4 and T-bet, two key IFN-γ gene imprinting factors. IFN-α primed naive B-cells for IFN-γ production and increased IFN-γ gene responsiveness to IL-12. IFN-γ continues this polarization by re-inducing T-bet and up-regulating IL-12Rβ2 expression. IFN-α and IFN-γ therefore pave the way for the action of IL-12. These results point to a coordinated action of IFN-α, IFN-γ and IL-12 in Be1 polarization of naive B-cells, and may provide new insights into the mechanisms by which type-I-interferons favor autoimmunity.

  11. Modular Study of the Type III Effector Repertoire in Pseudomonas syringae pv. tomato DC3000 Reveals a Matrix of Effector Interplay in Pathogenesis

    Directory of Open Access Journals (Sweden)

    Hai-Lei Wei

    2018-05-01

    Full Text Available Summary: The bacterial pathogen Pseudomonas syringae pv. tomato DC3000 suppresses the two-tiered innate immune system of Nicotiana benthamiana and other plants by injecting a complex repertoire of type III secretion effector (T3E proteins. Effectorless polymutant DC3000D36E was used with a modularized system for native delivery of the 29 DC3000 T3Es singly and in pairs. Assays of the performance of this T3E library in N. benthamiana leaves revealed a matrix of T3E interplay, with six T3Es eliciting death and eight others variously suppressing the death activity of the six. The T3E library was also interrogated for effects on DC3000D36E elicitation of a reactive oxygen species burst, for growth in planta, and for T3Es that reversed these effects. Pseudomonas fluorescens and Agrobacterium tumefaciens heterologous delivery systems yielded notably different sets of death-T3Es. The DC3000D36E T3E library system highlights the importance of 13 T3Es and their interplay in interactions with N. benthamiana. : Wei et al. used a Pseudomonas syringae strain lacking all known type III effectors with a modularized library expressing the 29 active effectors in the strain’s native repertoire, individually and in pairs, to comprehensively determine effector actions and interplay in inducing and suppressing responses associated with plant pathogenesis and immunity. Keywords: effector-triggered-immunity, pattern-triggered-immunity, Hop proteins, plant immunity, mini-Tn7

  12. Lymphocyte-platelet crosstalk in Graves' disease.

    Science.gov (United States)

    Kuznik, Boris I; Vitkovsky, Yuri A; Gvozdeva, Olga V; Solpov, Alexey V; Magen, Eli

    2014-03-01

    Platelets can modulate lymphocytes' role in the pathophysiology of thyroid autoimmune diseases. The present study was performed to clarify the status of platelet-lymphocyte subpopulations aggregation in circulating blood in patients with Graves' disease (GD). One hundred and fifty patients with GD (GD group) and 45 hyperthyroid patients with toxic multinodular goiter (TMG group) were recruited in the study. Control group consisted 150 healthy subjects. Immunophenotyping of lymphocytes was performed by flow cytometry. Detection of lymphocyte-platelet aggregates (LPAs) was done using light microscope after Ficoll-gradient centrifugation. The group of GD patients exhibited reduced CD8 lymphocyte and higher CD19 cell counts compared with TMG group and healthy controls. A greater number of activated CD3, HLA-DR+ lymphocytes were observed in GD than in TMG group and control group. GD group was characterized by lower blood platelet count (232 ± 89 × 10 cells/µL) than TMG group (251 ± 97 × 10 cells/µL; P TMG group (116 ± 67/µL, P < 0.005) and control group (104 ± 58 /µL; P < 0.001). GD is associated with higher levels of activated lymphocytes and lymphocyte-platelet aggregates.

  13. The phytopathogenic virulent effector protein RipI induces apoptosis in budding yeast Saccharomyces cerevisiae.

    Science.gov (United States)

    Deng, Meng-Ying; Sun, Yun-Hao; Li, Pai; Fu, Bei; Shen, Dong; Lu, Yong-Jun

    2016-10-01

    Virulent protein toxins secreted by the bacterial pathogens can cause cytotoxicity by various molecular mechanisms to combat host cell defense. On the other hand, these proteins can also be used as probes to investigate the defense pathway of host innate immunity. Ralstonia solanacearum, one of the most virulent bacterial phytopathogens, translocates more than 70 effector proteins via type III secretion system during infection. Here, we characterized the cytotoxicity of effector RipI in budding yeast Saccharomyce scerevisiae, an alternative host model. We found that over-expression of RipI resulted in severe growth defect and arginine (R) 117 within the predicted integrase motif was required for inhibition of yeast growth. The phenotype of death manifested the hallmarks of apoptosis. Our data also revealed that RipI-induced apoptosis was independent of Yca1 and mitochondria-mediated apoptotic pathways because Δyca1 and Δaif1 were both sensitive to RipI as compared with the wild type. We further demonstrated that RipI was localized in the yeast nucleus and the N-terminal 1-174aa was required for the localization. High-throughput RNA sequencing analysis showed that upon RipI over-expression, 101 unigenes of yeast ribosome presented lower expression level, and 42 GO classes related to the nucleus or recombination were enriched with differential expression levels. Taken together, our data showed that a nuclear-targeting effector RipI triggers yeast apoptosis, potentially dependent on its integrase function. Our results also provided an alternative strategy to dissect the signaling pathway of cytotoxicity induced by the protein toxins. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Effector and naturally occurring regulatory T cells display no abnormalities in activation induced cell death in NOD mice.

    Directory of Open Access Journals (Sweden)

    Ayelet Kaminitz

    Full Text Available BACKGROUND: Disturbed peripheral negative regulation might contribute to evolution of autoimmune insulitis in type 1 diabetes. This study evaluates the sensitivity of naïve/effector (Teff and regulatory T cells (Treg to activation-induced cell death mediated by Fas cross-linking in NOD and wild-type mice. PRINCIPAL FINDINGS: Both effector (CD25(-, FoxP3(- and suppressor (CD25(+, FoxP3(+ CD4(+ T cells are negatively regulated by Fas cross-linking in mixed splenocyte populations of NOD, wild type mice and FoxP3-GFP trangeneess. Proliferation rates and sensitivity to Fas cross-linking are dissociated in Treg cells: fast cycling induced by IL-2 and CD3/CD28 stimulation improve Treg resistance to Fas-ligand (FasL in both strains. The effector and suppressor CD4(+ subsets display balanced sensitivity to negative regulation under baseline conditions, IL-2 and CD3/CD28 stimulation, indicating that stimulation does not perturb immune homeostasis in NOD mice. Effective autocrine apoptosis of diabetogenic cells was evident from delayed onset and reduced incidence of adoptive disease transfer into NOD.SCID by CD4(+CD25(- T cells decorated with FasL protein. Treg resistant to Fas-mediated apoptosis retain suppressive activity in vitro. The only detectable differential response was reduced Teff proliferation and upregulation of CD25 following CD3-activation in NOD mice. CONCLUSION: These data document negative regulation of effector and suppressor cells by Fas cross-linking and dissociation between sensitivity to apoptosis and proliferation in stimulated Treg. There is no evidence that perturbed AICD in NOD mice initiates or promotes autoimmune insulitis.

  15. The Alpha-Melanocyte Stimulating Hormone Induces Conversion of Effector T Cells into Treg Cells

    Directory of Open Access Journals (Sweden)

    Andrew W. Taylor

    2011-01-01

    Full Text Available The neuropeptide alpha-melanocyte stimulating hormone (α-MSH has an important role in modulating immunity and homeostasis. The production of IFN-γ by effector T cells is suppressed by α-MSH, while TGF-β production is promoted in the same cells. Such α-MSH-treated T cells have immune regulatory activity and suppress hypersensitivity, autoimmune diseases, and graft rejection. Previous characterizations of the α-MSH-induced Treg cells showed that the cells are CD4+ T cells expressing the same levels of CD25 as effector T cells. Therefore, we further analyzed the α-MSH-induced Treg cells for expression of effector and regulatory T-cell markers. Also, we examined the potential for α-MSH-induced Treg cells to be from the effector T-cell population. We found that the α-MSH-induced Treg cells are CD25+  CD4+ T cells that share similar surface markers as effector T cells, except that they express on their surface LAP. Also, the α-MSH treatment augments FoxP3 message in the effector T cells, and α-MSH induction of regulatory activity was limited to the effector CD25+ T-cell population. Therefore, α-MSH converts effector T cells into Treg cells, which suppress immunity targeting specific antigens and tissues.

  16. In Planta Functional Analysis and Subcellular Localization of the Oomycete Pathogen Plasmopara viticola Candidate RXLR Effector Repertoire

    Directory of Open Access Journals (Sweden)

    Yunxiao Liu

    2018-04-01

    Full Text Available Downy mildew is one of the most destructive diseases of grapevine, causing tremendous economic loss in the grape and wine industry. The disease agent Plasmopara viticola is an obligate biotrophic oomycete, from which over 100 candidate RXLR effectors have been identified. In this study, 83 candidate RXLR effector genes (PvRXLRs were cloned from the P. viticola isolate “JL-7-2” genome. The results of the yeast signal sequence trap assay indicated that most of the candidate effectors are secretory proteins. The biological activities and subcellular localizations of all the 83 effectors were analyzed via a heterologous Agrobacterium-mediated Nicotiana benthamiana expression system. Results showed that 52 effectors could completely suppress cell death triggered by elicitin, 10 effectors could partially suppress cell death, 11 effectors were unable to suppress cell death, and 10 effectors themselves triggered cell death. Live-cell imaging showed that the majority of the effectors (76 of 83 could be observed with informative fluorescence signals in plant cells, among which 34 effectors were found to be targeted to both the nucleus and cytosol, 29 effectors were specifically localized in the nucleus, and 9 effectors were targeted to plant membrane system. Interestingly, three effectors PvRXLR61, 86 and 161 were targeted to chloroplasts, and one effector PvRXLR54 was dually targeted to chloroplasts and mitochondria. However, western blot analysis suggested that only PvRXLR86 carried a cleavable N-terminal transit peptide and underwent processing in planta. Many effectors have previously been predicted to target organelles, however, to the best of our knowledge, this is the first study to provide experimental evidence of oomycete effectors targeted to chloroplasts and mitochondria.

  17. TAL effectors: highly adaptable phytobacterial virulence factors and readily engineered DNA targeting proteins

    Science.gov (United States)

    Doyle, Erin L.; Stoddard, Barry L.; Voytas, Daniel F.; Bogdanove, Adam J.

    2013-01-01

    Transcription activator-like (TAL) effectors are transcription factors injected into plant cells by pathogenic bacteria in the genus Xanthomonas. They function as virulence factors by activating host genes important for disease, or as avirulence factors by turning on genes that provide resistance. DNA binding specificity is encoded by polymorphic repeats in each protein that correspond one-to-one with different nucleotides. This code has facilitated target identification and opened new avenues for engineering disease resistance. It has also enabled TAL effector customization for targeted gene control, genome editing, and other applications. This article reviews the structural basis for TAL effector-DNA specificity, the impact of the TAL effector-DNA code on plant pathology and engineered resistance, and recent accomplishments and future challenges in TAL effector-based DNA targeting. PMID:23707478

  18. SPRYSEC effectors: a versatile protein-binding platform to disrupt plant innate immunity

    Directory of Open Access Journals (Sweden)

    Amalia Diaz-Granados

    2016-10-01

    Full Text Available Persistent infections by sedentary plant-parasitic nematodes are a major threat to important food crops all over the world. These round worms manipulate host plant cell morphology and physiology to establish sophisticated feeding structures. Key modifications to plant cells during their transition into feeding structures are largely attributed to the activity of effectors secreted by the nematodes. The SPRYSEC effectors were initially identified in the potato cyst nematodes Globodera rostochiensis and G. pallida, and are characterized by a single SPRY domain, a non-catalytic domain present in modular proteins with different functions. The SPRY domain is wide-spread among eukaryotes and thought to be involved in mediating protein-protein interactions. Thus far, the SPRY domain is only reported as a functional domain in effectors of plant-parasitic nematodes, but not of other plant pathogens. SPRYSEC effectors have been implicated in both suppression and activation of plant immunity, but other possible roles in nematode virulence remain undefined. Here, we review the latest reports on the structure, function, and sequence diversity of SPRYSEC effectors, which provide support for a model featuring these effectors as a versatile protein-binding platform for the nematodes to target a wide range of host proteins during parasitism.

  19. In Utero Exposure to Histological Chorioamnionitis Primes the Exometabolomic Profiles of Preterm CD4+ T Lymphocytes.

    Science.gov (United States)

    Matta, Poojitha; Sherrod, Stacy D; Marasco, Christina C; Moore, Daniel J; McLean, John A; Weitkamp, Joern-Hendrik

    2017-11-01

    Histological chorioamnionitis (HCA) is an intrauterine inflammatory condition that increases the risk for preterm birth, death, and disability because of persistent systemic and localized inflammation. The immunological mechanisms sustaining this response in the preterm newborn remain unclear. We sought to determine the consequences of HCA exposure on the fetal CD4 + T lymphocyte exometabolome. We cultured naive CD4 + T lymphocytes from HCA-positive and -negative preterm infants matched for gestational age, sex, race, prenatal steroid exposure, and delivery mode. We collected conditioned media samples before and after a 6-h in vitro activation of naive CD4 + T lymphocytes with soluble staphylococcal enterotoxin B and anti-CD28. We analyzed samples by ultraperformance liquid chromatography ion mobility-mass spectrometry. We determined the impact of HCA on the CD4 + T lymphocyte exometabolome and identified potential biomarker metabolites by multivariate statistical analyses. We discovered that: 1) CD4 + T lymphocytes exposed to HCA exhibit divergent exometabolomic profiles in both naive and activated states; 2) ∼30% of detected metabolites differentially expressed in response to activation were unique to HCA-positive CD4 + T lymphocytes; 3) metabolic pathways associated with glutathione detoxification and tryptophan degradation were altered in HCA-positive CD4 + T lymphocytes; and 4) flow cytometry and cytokine analyses suggested a bias toward a T H 1-biased immune response in HCA-positive samples. HCA exposure primes the neonatal adaptive immune processes by inducing changes to the exometabolomic profile of fetal CD4 + T lymphocytes. These exometabolomic changes may link HCA exposure to T H 1 polarization of the neonatal adaptive immune response. Copyright © 2017 by The American Association of Immunologists, Inc.

  20. Development and testing of the cooling coil cleaning end effector

    International Nuclear Information System (INIS)

    Johnson, K.I.; Mullen, O.D.; Powell, M.R.; Daly, D.S.; Engel, D.W.

    1997-01-01

    The Retrieval Process Development and Enhancement (KPD ampersand E) program has developed and tested an end effector to support the waste retrieval mission at the Idaho National Engineering and Environmental Laboratory (INEEL). The end effector was developed specifically to remove a sticky waste material from the cooling coils in the High Level Liquid Waste (HLLW) tank, and to vacuum up a sediment layer that has settled beneath the cooling coils. An extensive testing program was conducted in the hydraulic test bed (HTB) at the Pacific Northwest National Laboratory (PNNL) to evaluate the performance of the end effector under simulated in-tank conditions. A mock up of the cooling coils was installed in the test bed tank, and simulated waste materials were included to represent the sticky waste on the tubes and the particulate waste settled beneath them. The testing program focused on assessing long-duration mining strategies for cleaning the cooling coils and removing the particulate waste forms. The report describes the results of the end effector testing program at PNNL. Section 2 describes the physical characteristics of the HLLW tanks, including the layout of the cooling coils, and it also describes what is known of the waste forms in the tanks. Section 3 describes the cleaning and retrieval strategy that was used in developing the end effector design. Section 4 describes the cooling coil mockup in the hydraulic test bed. Section 5 discusses the rationale used in selecting the simulants for the tarry waste and particulate waste forms. Section 6 describes the tests that were performed to evaluate cleaning of the cooling coils and retrieval of the particulate simulant. Section 7 summarizes the cleaning and retrieval tests, assesses the relative importance of cleaning the cooling coils and retrieving the particulate waste, and suggests modifications that would simplify the end effector design

  1. Identification and functional analysis of secreted effectors from phytoparasitic nematodes.

    Science.gov (United States)

    Rehman, Sajid; Gupta, Vijai K; Goyal, Aakash K

    2016-03-21

    Plant parasitic nematodes develop an intimate and long-term feeding relationship with their host plants. They induce a multi-nucleate feeding site close to the vascular bundle in the roots of their host plant and remain sessile for the rest of their life. Nematode secretions, produced in the oesophageal glands and secreted through a hollow stylet into the host plant cytoplasm, are believed to play key role in pathogenesis. To combat these persistent pathogens, the identity and functional analysis of secreted effectors can serve as a key to devise durable control measures. In this review, we will recapitulate the knowledge over the identification and functional characterization of secreted nematode effector repertoire from phytoparasitic nematodes. Despite considerable efforts, the identity of genes encoding nematode secreted proteins has long been severely hampered because of their microscopic size, long generation time and obligate biotrophic nature. The methodologies such as bioinformatics, protein structure modeling, in situ hybridization microscopy, and protein-protein interaction have been used to identify and to attribute functions to the effectors. In addition, RNA interference (RNAi) has been instrumental to decipher the role of the genes encoding secreted effectors necessary for parasitism and genes attributed to normal development. Recent comparative and functional genomic approaches have accelerated the identification of effectors from phytoparasitic nematodes and offers opportunities to control these pathogens. Plant parasitic nematodes pose a serious threat to global food security of various economically important crops. There is a wealth of genomic and transcriptomic information available on plant parasitic nematodes and comparative genomics has identified many effectors. Bioengineering crops with dsRNA of phytonematode genes can disrupt the life cycle of parasitic nematodes and therefore holds great promise to develop resistant crops against plant

  2. Analysis of changes in the percentage of B (CD19) and T (CD3) lymphocytes, nk cells, subsets CD4, CD8 in differentiated thyroid cancer patients treated with iodine-131

    International Nuclear Information System (INIS)

    Luo Quanyong; Yu Yongli; Chen Libo; Lu Hankui; Zhu Ruisen

    2004-01-01

    Objective: To evaluate the changes in the percentage of B (CD19) and T (CD3) lymphocytes, NK cells, subsets CD4, CD8 in patients with differentiated thyroid carcinoma (DTC) who received iodine-131 for therapeutic purposes. Methods: In this study, 102 DTC patients were divided into three groups. Group A, 8 cases received 1850 MBq of iodine-131 for the remnant thyroid ablation. Group B, 43 cases received 3700 MBq of iodine-131 for the treatment of cervical lymph node metastasis. Group C, 51 cases received 7400 MBq of iodine-131 for remote metastasis. All patients were in a hypothyroid state at the time of administration of iodine-131 and resumed L-thyroxine (2μg/Kg/day) 5 days after iodine-131 administration. The percentage of B and T lymphocytes, NK cells, subsets CD4, CD8 in peripheral blood were serially analyzed at baseline and at days 7, 30 and 90 after iodine-131 administration using a Coulter EPICS XL cytometer. Ten healthy individuals were used as a control group for lymphocyte subset values. Results: Comparing the basal lymphocyte subset levels in groups A, B and C with the control group, only NK cells showed significantly higher levels in patients than in controls (P=0.043). In group A, only the percentage of NK cells (P=0.031) and B cells (P =0.024) were reduced at day 7. In group B, a decrease in the percentage of NK cells at days 7(P=0.005), 30 (P=0.021) was observed, while a significant decrease in the percentage of B cells was only observed at day 7(P=0.006). Among T cells, only CD4+ was obviously affected, resulting in a reduction in the CD4+/CD8+ ratio at day 30 (P=0.034). In group C, patients showed a decrease in the percentage of NK cells at days 7 (P=0.023), 30 (P=0.006). A decrease in the percentage of both B and T lymphocytes was observed at days 7(P=0.020, 0.018 respectively), 30(P=0.041, 0.025 respectively). Among T cells, a decrease in the percentage of CD4+ and an increase in the percentage of CD8+ were observed, resulting in a marked

  3. Preoperative neutrophil-lymphocyte and platelet-lymphocyte ratios as independent predictors of cervical stromal involvement in surgically treated endometrioid adenocarcinoma

    Directory of Open Access Journals (Sweden)

    Wang D

    2013-03-01

    Full Text Available Dan Wang, Jia-Xin Yang, Dong-Yan Cao, Xi-Run Wan, Feng-Zhi Feng, Hui-Fang Huang, Keng Shen, Yang Xiang Department of Obstetrics and Gynecology, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, People's Republic of China Background: The purpose of this study was to evaluate the relationship between preoperative inflammatory markers (neutrophil-lymphocyte ratio and platelet-lymphocyte ratio and cervical stromal involvement in patients with endometrioid adenocarcinoma. Methods: We studied 318 patients with endometrioid adenocarcinoma who underwent comprehensive surgical staging. We used univariate and multivariate analyses of cervical stromal involvement and receiver-operating curves to calculate optimal cutoff values for neutrophil-lymphocyte and platelet-lymphocyte ratios to predict cervical stromal involvement. Results: The presence of cervical stromal involvement was associated with neutrophil-lymphocyte ratio and platelet-lymphocyte ratio (P = 0.009 and P = 0.031, respectively. Multivariate analysis showed that higher neutrophil-lymphocyte and platelet-lymphocyte ratios independently predicted cervical stromal involvement (odds ratio 3.10, 95% confidence interval 1.10–8.76, P = 0.032, and odds ratio 5.27, 95% confidence interval 1.94–14.35, P = 0.001, respectively. At a threshold of 2.01, the neutrophil-lymphocyte ratio was 71.0% sensitive and 63.8% specific for stromal involvement; at a 172.24 threshold, the platelet-lymphocyte ratio was 48.4% sensitive and 88.9% specific. Conclusion: Preoperative neutrophil-lymphocyte and platelet-lymphocyte ratios can help identify the risk of cervical stromal involvement in patients with endometrial cancer. Evaluating these ratios may help select patients who should be particularly watched and tested for cervical stromal involvement. Keywords: neutrophil-lymphocyte ratio, platelet-lymphocyte ratio, endometrioid adenocarcinoma

  4. Exosomes: novel effectors of human platelet lysate activity

    Directory of Open Access Journals (Sweden)

    E Torreggiani

    2014-09-01

    Full Text Available Despite the popularity of platelet-rich plasma (PRP and platelet lysate (PL in orthopaedic practice, the mechanism of action and the effectiveness of these therapeutic tools are still controversial. So far, the activity of PRP and PL has been associated with different growth factors (GF released during platelet degranulation. This study, for the first time, identifies exosomes, nanosized vesicles released in the extracellular compartment by a number of elements, including platelets, as one of the effectors of PL activity. Exosomes were isolated from human PL by differential ultracentrifugation, and analysed by electron microscopy and Western blotting. Bone marrow stromal cells (MSC treated with three different exosome concentrations (0.6 μg, 5 μg and 50 μg showed a significant, dose-dependent increase in cell proliferation and migration compared to the control. In addition, osteogenic differentiation assays demonstrated that exosome concentration differently affected the ability of MSC to deposit mineralised matrix. Finally, the analysis of exosome protein content revealed a higher amount of basic fibroblast growth factor (bFGF, vascular endothelial growth factor (VEGF, platelet-derived growth factor (PDGF-BB and transforming growth factor beta 1 (TGF-β1 as compared to PL. In regards to RNA content, an enrichment of small RNAs in exosomes as compared to donor platelets has been found. These results suggest that exosomes consistently contribute to PL activity and could represent an advantageous nanodelivery system for cell-free regeneration therapies.

  5. Chronic lymphocytic leukemia (CLL)

    Science.gov (United States)

    ... is used for painful and enlarged lymph nodes. Blood transfusions or platelet transfusions may be required if blood ... unexplained fatigue, bruising, excessive sweating, or weight loss. Alternative ... Leukemia - chronic lymphocytic (CLL); Blood cancer - chronic lymphocytic leukemia; Bone marrow cancer - chronic ...

  6. Suppressive versus augmenting effect of the same pretreatment regimen in two murine tumor systems with distinct effector mechanisms

    International Nuclear Information System (INIS)

    Fujiwara, Hiromi; Hamaoka, Toshiyuki; Kitagawa, Masayasu

    1978-01-01

    The effect of presensitization with x-irradiated tumor cells on the development of host's immune resistance against the tumor-associated transplantation antigens (TATA) was investigated in two syngeneic tumor systems with distinct effector mechanisms. When X5563 plasmacytoma, to which immune resistance was mediated exclusively by killer T lymphocytes, was intravenously inoculated into syngeneic C3H/He mice with lower number after 7000 R x-irradiation, the mice failed to exhibit any protective immunity against the subsequent challenge with viable tumor cells. Moreover, these mice lost their capability to develop any immune resistance even after an appropriate immunization procedure. The immunodepression induced by such a pretreatment regimen was specific for X5563 tumor. While no suppressor cell activity was detected in the above pretreated mice, serum factor(s) from these mice was virtually responsible for this suppression. When the serum factor mediating this tumor-specific suppression was fractionated on the Sephadex G-200 column, the suppressive activity was found in albumin-corresponding fraction, free of any immunoglobulin component. In contrast, in MM102 mammary tumor system, in which immune resistance is solely mediated by tumor-specific antibody, the pretreatment with x-irradiated MM102 cells augmented the induction of anti-tumor immunity. These results indicate that while tumor antigens given in the form of x-irradiated tumor cells suppress the induction of killer T cell-mediated immunity in one system, the same presensitization regimen of tumor antigens augments the antibody-mediated immunity in another system, thus giving a divergent effect on the distinct effector mechanisms of syngeneic tumor immunity. (author)

  7. Direct regulation of Gata3 expression determines the T helper differentiation potential of Notch

    NARCIS (Netherlands)

    Amsen, Derk; Antov, Andrey; Jankovic, Dragana; Sher, Alan; Radtke, Freddy; Souabni, Abdallah; Busslinger, Meinrad; McCright, Brent; Gridley, Thomas; Flavell, Richard A.

    2007-01-01

    CD4(+) T helper cells differentiate into T helper 1 (Th1) or Th2 effector lineages, which orchestrate immunity to different types of microbes. Both Th1 and Th2 differentiation can be induced by Notch, but what dictates which of these programs is activated in response to Notch is not known. By using

  8. Time-effect relationship of chromosome aberrations in peripheral lymphocytes after radiation therapy for seminoma

    International Nuclear Information System (INIS)

    Bauchinger, M.; Schmid, E.; Braselmann, H.; Willich, N.; Clemm, C.

    1989-01-01

    The time-effect relationship of dicentrics and cells containing unstable chromosome abnormalities C u cells) was studied in peripheral lymphocytes of 40 blood samples from 23 suffering from seminoma during a time period of 0-1720 days after radiation therapy. Nine patients were studied before treatment. Since the half-time for the disappearance of damaged cells from circulating blood is an increasing function of post-exposure time it can only be expressed as a differential value. The present model discriminates between the mean lifetime m for lymphocytes and a parameter q which is the differential half-time for the decline of damaged cells immediately after exposure (t=0). If the time t is hort compared with m the decline is asymptotically time-hyperbolic rather than exponential and can be described by q only. According to recalculations of previous data, comprising 30 years post exposure, m approximates 10 years. Differential half-times can be derived for any time post treatment within the analysed time period for the decline of the incidence of dicentrics. For example at the end of therapy (t=0) the differential half-time was calculated to be 0.4 years and at 1720 days post exposure 3.6 years resulted. The corresponding values for the percentage of C u cells cannot be derived for t=0; at 1720 days 3.9 years resulted. (author). 13 refs.; 3 figs.; 3 tabs

  9. Induction of NFATc2 expression by interleukin 6 promotes T helper type 2 differentiation.

    Science.gov (United States)

    Diehl, Sean; Chow, Chi-Wing; Weiss, Linda; Palmetshofer, Alois; Twardzik, Thomas; Rounds, Laura; Serfling, Edgar; Davis, Roger J; Anguita, Juan; Rincón, Mercedes

    2002-07-01

    Interleukin (IL)-6 is produced by professional antigen-presenting cells (APCs) such as B cells, macrophages, and dendritic cells. It has been previously shown that APC-derived IL-6 promotes the differentiation of naive CD4+ T cells into effector T helper type 2 (Th2) cells. Here, we have studied the molecular mechanism for IL-6-mediated Th2 differentiation. During the activation of CD4+ T cells, IL-6 induces the production of IL-4, which promotes the differentiation of these cells into effector Th2 cells. Regulation of IL-4 gene expression by IL-6 is mediated by nuclear factor of activated T cells (NFAT), as inhibition of NFAT prevents IL-6-driven IL-4 production and Th2 differentiation. IL-6 upregulates NFAT transcriptional activity by increasing the levels of NFATc2. The ability of IL-6 to promote Th2 differentiation is impaired in CD4+ T cells that lack NFATc2, demonstrating that NFATc2 is required for regulation of IL-4 gene expression by IL-6. Regulation of NFATc2 expression and NFAT transcriptional activity represents a novel pathway by which IL-6 can modulate gene expression.

  10. Pharmacokinetics and modeling of immune cell trafficking: quantifying differential influences of target tissues versus lymphocytes in SJL and lipopolysaccharide-treated mice

    Directory of Open Access Journals (Sweden)

    Banks William A

    2012-10-01

    Full Text Available Abstract Background Immune cell trafficking into the CNS and other tissues plays important roles in health and disease. Rapid quantitative methods are not available that could be used to study many of the dynamic aspects of immune cell-tissue interactions. Methods We used pharmacokinetics and modeling to quantify and characterize the trafficking of radioactively labeled lymphocytes into brain and peripheral tissues. We used variance from two-way ANOVAs with 2 × 2 experimental designs to model the relative influences of lymphocytes and target tissues in trafficking. Results We found that in male CD-1 mice, about 1 in 5,000 intravenously injected lymphocytes entered each gram of brain. Uptake by brain was 2 to 3 times higher in naïve SJL females, but uptake by spleen and clearance from blood was lower, demonstrating a dichotomy in immune cell distribution. Treatment of CD-1 mice with lipopolysaccharide (LPS increased immune cell uptake into brain but decreased uptake by spleen and axillary nodes. Conclusions Differences in brain uptake and in uptake by spleen between SJL and CD-1 mice were primarily determined by lymphocytes, whereas differences in uptake with LPS were primarily determined by lymphocytes for the brain but by the tissues for the spleen and the axillary lymph node. These results show that immune cells normally enter the CNS and that tissues and immune cells interact in ways that can be quantified by pharmacokinetic models.

  11. Milk-derived GM3 and GD3 differentially inhibit dendritic cell maturation and effector functionalities

    DEFF Research Database (Denmark)

    Brønnum, H.; Seested, T.; Hellgren, Lars

    2005-01-01

    value of gangliosides in breast milk has yet to be elucidated but when milk is ingested, dietary gangliosides might conceptually affect immune cells, such as dendritic cells (DCs). In this study, we address the in vitro effect of GD(3) and GM(3) on DC effector functionalities. Treatment of bone marrow......Gangliosides are complex glycosphingolipids, which exert immune-modulating effects on various cell types. Ganglioside GD(3) and GM(3) are the predominant gangliosides of human breast milk but during the early phase of lactation, the content of GD(3) decreases while GM(3) increases. The biological...... by GM(3,) and the potency of DCs to activate CD4(+) cells in MLR was unaffected by GM(3). However, both gangliosides suppressed expression of CD40, CD80, CD86 and major histocompatibility complex class II on DCs. Because GD(3) overall inhibits DC functionalities more than GM(3), the immune modulating...

  12. Milk-derived GM(3) and GD(3) differentially inhibit dendritic cell maturation and effector functionalities

    DEFF Research Database (Denmark)

    Bronnum, H.; Seested, T.; Hellgren, Lars

    2005-01-01

    value of gangliosides in breast milk has yet to be elucidated but when milk is ingested, dietary gangliosides might conceptually affect immune cells, such as dendritic cells (DCs). In this study, we address the in vitro effect of GD(3) and GM(3) on DC effector functionalities. Treatment of bone marrow......Gangliosides are complex glycosphingolipids, which exert immune-modulating effects on various cell types. Ganglioside GD(3) and GM(3) are the predominant gangliosides of human breast milk but during the early phase of lactation, the content of GD(3) decreases while GM(3) increases. The biological...... by GM(3,) and the potency of DCs to activate CD4(+) cells in MLR was unaffected by GM(3). However, both gangliosides suppressed expression of CD40, CD80, CD86 and major histocompatibility complex class II on DCs. Because GD(3) overall inhibits DC functionalities more than GM(3), the immune modulating...

  13. Spatial Organization and Molecular Correlation of Tumor-Infiltrating Lymphocytes Using Deep Learning on Pathology Images

    Directory of Open Access Journals (Sweden)

    Joel Saltz

    2018-04-01

    Full Text Available Summary: Beyond sample curation and basic pathologic characterization, the digitized H&E-stained images of TCGA samples remain underutilized. To highlight this resource, we present mappings of tumor-infiltrating lymphocytes (TILs based on H&E images from 13 TCGA tumor types. These TIL maps are derived through computational staining using a convolutional neural network trained to classify patches of images. Affinity propagation revealed local spatial structure in TIL patterns and correlation with overall survival. TIL map structural patterns were grouped using standard histopathological parameters. These patterns are enriched in particular T cell subpopulations derived from molecular measures. TIL densities and spatial structure were differentially enriched among tumor types, immune subtypes, and tumor molecular subtypes, implying that spatial infiltrate state could reflect particular tumor cell aberration states. Obtaining spatial lymphocytic patterns linked to the rich genomic characterization of TCGA samples demonstrates one use for the TCGA image archives with insights into the tumor-immune microenvironment. : Tumor-infiltrating lymphocytes (TILs were identified from standard pathology cancer images by a deep-learning-derived “computational stain” developed by Saltz et al. They processed 5,202 digital images from 13 cancer types. Resulting TIL maps were correlated with TCGA molecular data, relating TIL content to survival, tumor subtypes, and immune profiles. Keywords: digital pathology, immuno-oncology, machine learning, lymphocytes, tumor microenvironment, deep learning, tumor-infiltrating lymphocytes, artificial intelligence, bioinformatics, computer vision

  14. Expression of calpain-calpastatin system (CCS) member proteins in human lymphocytes of young and elderly individuals; pilot baseline data for the CALPACENT project.

    Science.gov (United States)

    Mikosik, Anna; Foerster, Jerzy; Jasiulewicz, Aleksandra; Frąckowiak, Joanna; Colonna-Romano, Giuseppina; Bulati, Matteo; Buffa, Silvio; Martorana, Adriana; Caruso, Calogero; Bryl, Ewa; Witkowski, Jacek M

    2013-07-08

    Ubiquitous system of regulatory, calcium-dependent, cytoplasmic proteases - calpains - and their endogenous inhibitor - calpastatin - is implicated in the proteolytic regulation of activation, proliferation, and apoptosis of many cell types. However, it has not been thoroughly studied in resting and activated human lymphocytes yet, especially in relation to the subjects' ageing process. The CALPACENT project is an international (Polish-Italian) project aiming at verifying the hypothesis of the role of calpains in the function of peripheral blood immune cells of Polish (Pomeranian) and Italian (Sicilian) centenarians, apparently relatively preserved in comparison to the general elderly population. In this preliminary report we aimed at establishing and comparing the baseline levels of expression of μ- and m-calpain and calpastatin in various, phenotypically defined, populations of human peripheral blood lymphocytes for healthy elderly Sicilians and Poles, as compared to these values observed in young cohort. We have found significant differences in the expression of both μ- and m-calpain as well as calpastatin between various populations of peripheral blood lymphocytes (CD4+, CD8+ and CD19+), both between the age groups compared and within them. Interestingly, significantly higher amounts of μ- and m-calpains but not of calpastatin could be demonstrated in the CD4+CD28- and CD8+CD28- lymphocytes of old subjects (but not in the cells of young individuals), as compared to their CD28+ counterparts. Finally, decreased expression of both calpains in the elderly T cells is not related to the accumulation of effector/memory (CD45RO+) cells in the latter, as the expression of both calpains does not differ significantly between the naïve and memory T cells, while is significantly lower for elderly lymphocytes if both populations are taken separately. Observed differences in the amounts of CCS member proteins between various populations of lymphocytes of young and elderly

  15. A novel intracellular pool of LFA-1 is critical for asymmetric CD8+ T cell activation and differentiation.

    Science.gov (United States)

    Capece, Tara; Walling, Brandon L; Lim, Kihong; Kim, Kyun-Do; Bae, Seyeon; Chung, Hung-Li; Topham, David J; Kim, Minsoo

    2017-11-06

    The integrin lymphocyte function-associated antigen 1 (LFA-1; CD11a/CD18) is a key T cell adhesion receptor that mediates stable interactions with antigen-presenting cell (APC), as well as chemokine-mediated migration. Using our newly generated CD11a-mYFP knock-in mice, we discovered that naive CD8 + T cells reserve a significant intracellular pool of LFA-1 in the uropod during migration. Intracellular LFA-1 quickly translocated to the cell surface with antigenic stimulus. Importantly, the redistribution of intracellular LFA-1 at the contact with APC was maintained during cell division and led to an unequal inheritance of LFA-1 in divided T cells. The daughter CD8 + T cells with disparate LFA-1 expression showed different patterns of migration on ICAM-1, APC interactions, and tissue retention, as well as altered effector functions. In addition, we identified Rab27 as an important regulator of the intracellular LFA-1 translocation. Collectively, our data demonstrate that an intracellular pool of LFA-1 in naive CD8 + T cells plays a key role in T cell activation and differentiation. © 2017 Capece et al.

  16. T3SEdb: data warehousing of virulence effectors secreted by the bacterial Type III Secretion System.

    Science.gov (United States)

    Tay, Daniel Ming Ming; Govindarajan, Kunde Ramamoorthy; Khan, Asif M; Ong, Terenze Yao Rui; Samad, Hanif M; Soh, Wei Wei; Tong, Minyan; Zhang, Fan; Tan, Tin Wee

    2010-10-15

    Effectors of Type III Secretion System (T3SS) play a pivotal role in establishing and maintaining pathogenicity in the host and therefore the identification of these effectors is important in understanding virulence. However, the effectors display high level of sequence diversity, therefore making the identification a difficult process. There is a need to collate and annotate existing effector sequences in public databases to enable systematic analyses of these sequences for development of models for screening and selection of putative novel effectors from bacterial genomes that can be validated by a smaller number of key experiments. Herein, we present T3SEdb http://effectors.bic.nus.edu.sg/T3SEdb, a specialized database of annotated T3SS effector (T3SE) sequences containing 1089 records from 46 bacterial species compiled from the literature and public protein databases. Procedures have been defined for i) comprehensive annotation of experimental status of effectors, ii) submission and curation review of records by users of the database, and iii) the regular update of T3SEdb existing and new records. Keyword fielded and sequence searches (BLAST, regular expression) are supported for both experimentally verified and hypothetical T3SEs. More than 171 clusters of T3SEs were detected based on sequence identity comparisons (intra-cluster difference up to ~60%). Owing to this high level of sequence diversity of T3SEs, the T3SEdb provides a large number of experimentally known effector sequences with wide species representation for creation of effector predictors. We created a reliable effector prediction tool, integrated into the database, to demonstrate the application of the database for such endeavours. T3SEdb is the first specialised database reported for T3SS effectors, enriched with manual annotations that facilitated systematic construction of a reliable prediction model for identification of novel effectors. The T3SEdb represents a platform for inclusion of

  17. T3SEdb: data warehousing of virulence effectors secreted by the bacterial Type III Secretion System

    Directory of Open Access Journals (Sweden)

    Tong Minyan

    2010-10-01

    Full Text Available Abstract Background Effectors of Type III Secretion System (T3SS play a pivotal role in establishing and maintaining pathogenicity in the host and therefore the identification of these effectors is important in understanding virulence. However, the effectors display high level of sequence diversity, therefore making the identification a difficult process. There is a need to collate and annotate existing effector sequences in public databases to enable systematic analyses of these sequences for development of models for screening and selection of putative novel effectors from bacterial genomes that can be validated by a smaller number of key experiments. Results Herein, we present T3SEdb http://effectors.bic.nus.edu.sg/T3SEdb, a specialized database of annotated T3SS effector (T3SE sequences containing 1089 records from 46 bacterial species compiled from the literature and public protein databases. Procedures have been defined for i comprehensive annotation of experimental status of effectors, ii submission and curation review of records by users of the database, and iii the regular update of T3SEdb existing and new records. Keyword fielded and sequence searches (BLAST, regular expression are supported for both experimentally verified and hypothetical T3SEs. More than 171 clusters of T3SEs were detected based on sequence identity comparisons (intra-cluster difference up to ~60%. Owing to this high level of sequence diversity of T3SEs, the T3SEdb provides a large number of experimentally known effector sequences with wide species representation for creation of effector predictors. We created a reliable effector prediction tool, integrated into the database, to demonstrate the application of the database for such endeavours. Conclusions T3SEdb is the first specialised database reported for T3SS effectors, enriched with manual annotations that facilitated systematic construction of a reliable prediction model for identification of novel effectors

  18. Chronic lymphocytic thyroiditis is associated with invasive characteristics of differentiated thyroid carcinoma in children and adolescents.

    Science.gov (United States)

    Iliadou, Paschalia K; Effraimidis, Grigoris; Konstantinos, Michalakis; Grigorios, Panagiotou; Mitsakis, Periklis; Patakiouta, Frideriki; Pazaitou-Panayiotou, Kalliopi

    2015-12-01

    The association between chronic lymphocytic thyroiditis (CLT) and thyroid cancer is an interesting topic. The aim of the present study was to evaluate if demographic and histological characteristics as well as the long-term outcome of thyroid cancer was different in children and adolescents with and without CLT. The medical records of children and adolescents (≤21 years old) were reviewed. The following data were recorded: gender, year and age at diagnosis, family history of thyroid cancer, history of external radiation therapy, histological type (papillary and variants, follicular and variants), tumour size, multifocality, infiltration of thyroid parenchyma or surrounding soft tissues, vascular invasion, presence of lymph node and distant metastases. Information about the presence of TgAb and TPOAb was also collected. One hundred eight children and adolescents (median age 19.0, interquartile range 4.0 years) were diagnosed with differentiated thyroid carcinoma (DTC); 31 patients (28.7%) presented histological characteristics compatible with CLT. Infiltration of thyroid parenchyma was more frequent in patients with CLT compared to patients without (74.2% vs 48.1% respectively, P=0.024). Familial papillary thyroid carcinoma (PTC) was more frequent in patients with CLT compared to those without CLT (20.7% vs 2.8% respectively, P=0.009). There was no better outcome with respect to the presence of CLT or not. Children and adolescents with CLT present more frequently familial PTC as well as thyroid cancer with invasive characteristics. © 2015 European Society of Endocrinology.

  19. Radiation sensitivity of human malignant lymphocytes

    International Nuclear Information System (INIS)

    Seshadri, R.; Matthews, C.; Morley, A.A.

    1985-01-01

    A simple and rapid in vitro technique to assess the sensitivity of human malignant lymphocytes to roentgen irradiation is described. A variety of established malignant lymphocyte cell lines were cloned in microwells and clone survival was used as the end-point. The survival of the clonogenic malignant lymphocyte down to a fraction of approximately 0.001 could be measured accurately. Except for a T-cell line, the radiation sensitivities of the cell lines were similar to that of normal T-lymphocytes. (orig.)

  20. Animal models for studies of chromosome aberration induction in PHA-stimulated lymphocytes

    International Nuclear Information System (INIS)

    Liniecki, J.; Bajerska, A.; Wyszynskaa, K.

    1978-01-01

    To assess the appropriate time for harvesting cultures of rabbit and swine lymphocytes, whole blood of these animals was irradiated with 300 rad γ-rays and microcultures were established using Ham's F-10 medium. Mitotic and tetraploidy indices, dicentrics per cell and the percentage of dicentric or ring-carrying cells, unaccompanied by acentrics, were determined as a function of culture duration. The same procedure was applied to human blood. The percentage of cells in first and second mitosis was determined in rabbit and swine lymphocyte cultures at selected times after stimulation using the FPG technique for differential staining of sister chromatids. The first mitotic waves appear at 30 +- 1, 36 +- 2, and 45 +- 1 h after PHA stimulation for pig, rabbit and man respectively. Correspondingly, in the three species a significant percentage of cells in second mitosis is already present by 36, 44 and 48 to 52 h and is accompanied by a steep reduction in the dicentric yields. These proposed culture times for rabbit and swine lymphocytes are shorter than those at which the majority of relevant studies reported in the literature have been performed. (author)

  1. A comparison of the neutrophil-lymphocyte, platelet-lymphocyte and monocyte-lymphocyte ratios in schizophrenia and bipolar disorder patients - a retrospective file review.

    Science.gov (United States)

    Özdin, Selçuk; Sarisoy, Gökhan; Böke, Ömer

    2017-10-01

    Neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR) and monocyte-lymphocyte ratio (MLR) have recently been used as indicators of inflammation. Higher MLR and PLR values have been determined in the euthymic and manic periods in patients with bipolar disorder compared to a control group. High NLR values were determined in the only study investigating this ratio in schizophrenia patients. The purpose of this study was to compare NLR, PLR and MLR values and complete blood count elements in patients receiving treatment and hospitalized due to schizophrenic psychotic episode and bipolar disorder manic episode. All patients meeting the inclusion criteria among subjects receiving treatment and hospitalized due to schizophrenia-psychotic episode and bipolar affective disorder-manic episode at the Ondokuz Mayıs University Medical Faculty Psychiatry Department, Turkey, in 2012-2016 were included in our study. A total of 157 healthy donors were included as a control group. White blood cell (WBC), neutrophil, lymphocyte, platelet and monocyte numbers were noted retrospectively from complete blood counts at time of admission, and NLR, PLR and MLR were calculated from these. NLR, PLR and MLR values and platelet numbers in this study were higher and lymphocyte numbers were lower in bipolar disorder patients compared to the controls. Elevation in NLR, MLR and PLR values and neutrophil numbers and lower lymphocyte numbers were determined in schizophrenia patients compared to the controls. Higher NLR and MLR values were found in schizophrenia patients compared to bipolar disorder. Findings of our study supported the inflammation hypothesis for schizophrenia and bipolar disorder.

  2. Hitting the Sweet Spot: Glycans as Targets of Fungal Defense Effector Proteins

    Directory of Open Access Journals (Sweden)

    Markus Künzler

    2015-05-01

    Full Text Available Organisms which rely solely on innate defense systems must combat a large number of antagonists with a comparatively low number of defense effector molecules. As one solution of this problem, these organisms have evolved effector molecules targeting epitopes that are conserved between different antagonists of a specific taxon or, if possible, even of different taxa. In order to restrict the activity of the defense effector molecules to physiologically relevant taxa, these target epitopes should, on the other hand, be taxon-specific and easily accessible. Glycans fulfill all these requirements and are therefore a preferred target of defense effector molecules, in particular defense proteins. Here, we review this defense strategy using the example of the defense system of multicellular (filamentous fungi against microbial competitors and animal predators.

  3. Type IV Secretion System of Brucella spp. and its Effectors

    Directory of Open Access Journals (Sweden)

    Yuehua eKe

    2015-10-01

    Full Text Available Brucella spp. cause brucellosis in domestic and wild animals. They are intracellular bacterial pathogens and used as model organisms to study intracellular bacterial infections. Brucella VirB T4SS is a key virulence factor that plays important roles in mediating intracellular survival and manipulating host immune response to infection. In this review, we will discuss roles of Brucella VirB T4SS and in more detail of all 15 identified effectors, which may be crucial for Brucella pathogenesis. VirB T4SS regulates the inflammation response and manipulates vesicle trafficking inside host cells, suggesting that it plays crucial roles in the inhibition of the host immune response and intracellular survival during infection. So, we listed some key molecular events in the intracellular life cycle of Brucella potentially targeted by the VirB T4SS effectors. Elucidating functions of the effectors secreted will be crucial to clarifying mechanism of T4SS during infection. Studying the effectors secreted by Brucella spp. might provide insights into the mechanisms by which the bacteria hijack the host signaling pathways, which help us to develop better vaccines and therapies against brucellosis.

  4. Type IV secretion system of Brucella spp. and its effectors.

    Science.gov (United States)

    Ke, Yuehua; Wang, Yufei; Li, Wengfeng; Chen, Zeliang

    2015-01-01

    Brucella spp. are intracellular bacterial pathogens that cause infection in domestic and wild animals. They are often used as model organisms to study intracellular bacterial infections. Brucella VirB T4SS is a key virulence factor that plays important roles in mediating intracellular survival and manipulating host immune response to infection. In this review, we discuss the roles of Brucella VirB T4SS and 15 effectors that are proposed to be crucial for Brucella pathogenesis. VirB T4SS regulates the inflammation response and manipulates vesicle trafficking inside host cells. VirB T4SS also plays crucial roles in the inhibition of the host immune response and intracellular survival during infection. Here, we list the key molecular events in the intracellular life cycle of Brucella that are potentially targeted by the VirB T4SS effectors. Elucidating the functions of these effectors will help clarify the molecular role of T4SS during infection. Furthermore, studying the effectors secreted by Brucella spp. might provide insights into the mechanisms used by the bacteria to hijack the host signaling pathways and aid in the development of better vaccines and therapies against brucellosis.

  5. Polarization of T-helper lymphocytes toward the Th2 phenotype in uremic patients.

    Science.gov (United States)

    Libetta, C; Rampino, T; Dal Canton, A

    2001-08-01

    T-helper (Th) lymphocytes consist of Th1 and Th2 subsets. Th1 cells are effectors of cell-mediated immunity and secrete interferon-gamma (IFN-gamma), which recruits new Th1 cells in cooperation with interleukin-12 (IL-12; produced by monocytes) and inhibits Th2 differentiation. Th2 cells produce IL-4 and IL-10, which inhibit IFN-gamma secretion and cell immunity. We investigated whether the impaired immune response in uremia is associated with an altered balance of Th1/Th2. Peripheral-blood mononuclear cells (PBMCs) were collected from patients with chronic renal failure (CRF) on conservative treatment (CRF patients), patients with end-stage renal disease (ESRD) on regular hemodialysis therapy (ESRD-HD patients), and healthy controls (CON). CD4(+) cells were isolated from PBMCs by negative selection using a magnetic labeling system. PBMCs and purified CD4(+) cells were cultured in Iscove's medium and Iscove's medium plus mitogens (phytohemagglutinin and lipopolysaccharide). IFN-gamma, IL-12, IL-4, and IL-10 were measured in supernatant. The constitutive release of IL-4 and IL-10 by PBMCs and CD4(+) cells of CRF and ESRD-HD patients was increased by five to eight times in comparison with CON (P CON, 115.8 pg/2 x10(6) cells; CRF, 81.8 pg/2 x10(6) cells; ESRD-HD, 9.3 pg/2 x10(6) cells; CD4(+) cells: CON, 358.0 pg/5 x 10(5) cells; CRF, 165.4 pg/5 x 10(5) cells; ESRD-HD, 43.5 pg/5 x 10(5) cells). The ability of PBMCs of ESRD-HD patients to secrete IFN-gamma was recovered after IL-4 and IL-10 neutralization. Uremia is associated with a prevalence of Th1 over Th2 cells and a configuration of cytokine network that depresses cell-mediated immunity.

  6. Identification of Novel Host Interactors of Effectors Secreted by Salmonella and Citrobacter

    Energy Technology Data Exchange (ETDEWEB)

    Sontag, Ryan L.; Nakayasu, Ernesto S.; Brown, Roslyn N.; Niemann, George S.; Sydor, Michael A.; Sanchez, Octavio; Ansong, Charles; Lu, Shao-Yeh; Choi, Hyungwon; Valleau, Dylan; Weitz, Karl K.; Savchenko, Alexei; Cambronne, Eric D.; Adkins, Joshua N.; McFall-Ngai, Margaret J.

    2016-07-12

    Many pathogenic bacteria of the familyEnterobacteriaceaeuse type III secretion systems to inject virulence proteins, termed “effectors,” into the host cell cytosol. Although host-cellular activities of several effectors have been demonstrated, the function and host-targeted pathways of most of the effectors identified to date are largely undetermined. To gain insight into host proteins targeted by bacterial effectors, we performed coaffinity purification of host proteins from cell lysates using recombinant effectors from theEnterobacteriaceaeintracellular pathogensSalmonella entericaserovar Typhimurium andCitrobacter rodentium. We identified 54 high-confidence host interactors for theSalmonellaeffectors GogA, GtgA, GtgE, SpvC, SrfH, SseL, SspH1, and SssB collectively and 21 interactors for theCitrobactereffectors EspT, NleA, NleG1, and NleK. We biochemically validated the interaction between the SrfHSalmonellaprotein and the extracellular signal-regulated kinase 2 (ERK2) host protein kinase, which revealed a role for this effector in regulating phosphorylation levels of this enzyme, which plays a central role in signal transduction.

    IMPORTANCEDuring infection, pathogenic bacteria face an adverse environment of factors driven by both cellular and humoral defense mechanisms. To help evade the immune response and ultimately proliferate inside the host, many bacteria evolved specialized secretion systems to deliver effector proteins directly into host cells. Translocated effector proteins function to subvert host defense mechanisms. Numerous pathogenic bacteria use a specialized secretion system called type III secretion to deliver effectors into the host cell cytosol. Here, we identified 75 new host targets ofSalmonellaandCitrobactereffectors, which will help elucidate their mechanisms of

  7. MRI of lymphocytic hypophysitis

    International Nuclear Information System (INIS)

    Feng Feng; Li Mingli; Li Xiaozhen; Meng Chunling; Jin zhengyu

    2005-01-01

    Objective: To describe the MR findings in patients with lymphocytic hypophysitis (LyH), and to discuss MR diagnostic value and limit in this disease entity and its differentiation with pituitary adenoma. Methods: Five pathologically proven cases of LyH were recruited in this study. The main complaints of the patients were polydipsia, polyuria, and headache. The preoperative MR images and clinical manifestations were analyzed retrospectively. Results: MR findings of the 5 patients with LyH included enlargement of pituitary gland, stalk thickening, disappearance of high signal of neurohypophysis on T 1 WI, and marked Gadolinium enhancement of the lesions. Homogeneous enhancement was found in 2 cases, while heterogeneous enhancement was in 3 cases. Involvement of the cavernous sinus and dura mater on dorsum sella and clivus were found in 2 patients. Conclusion: The diagnosis of LyH should be suggested when the enlarged pituitary gland is associated with central diabetes insipidus, and with/without dysfunction of adenohypophysis. (authors)

  8. Differential expression of NK receptors CD94 and NKG2A by T cells in rheumatoid arthritis patients in remission compared to active disease.

    LENUS (Irish Health Repository)

    Walsh, Ceara E

    2011-01-01

    TNF inhibitors (TNFi) have revolutionised the treatment of rheumatoid arthritis (RA). Natural killer (NK) cells and Natural Killer Cell Receptor+ T (NKT) cells comprise important effector lymphocytes whose activity is tightly regulated through surface NK receptors (NKRs). Dysregulation of NKRs in patients with autoimmune diseases has been shown, however little is known regarding NKRs expression in patients with TNFi-induced remission and in those who maintain remission vs disease flare following TNFi withdrawal.

  9. Opinion: Interactions of innate and adaptive lymphocytes

    Science.gov (United States)

    Gasteiger, Georg; Rudensky, Alexander Y.

    2015-01-01

    Innate lymphocytes, including natural killer (NK) cells and the recently discovered innate lymphoid cells (ILCs) have crucial roles during infection, tissue injury and inflammation. Innate signals regulate the activation and homeostasis of innate lymphocytes. Less well understood is the contribution of the adaptive immune system to the orchestration of innate lymphocyte responses. We review our current understanding of the interactions between adaptive and innate lymphocytes, and propose a model in which adaptive T cells function as antigen-specific sensors for the activation of innate lymphocytes to amplify and instruct local immune responses. We highlight the potential role of regulatory and helper T cells in these processes and discuss major questions in the emerging area of crosstalk between adaptive and innate lymphocytes. PMID:25132095

  10. Phytoplasma effector SAP54 induces indeterminate leaf-like flower development in Arabidopsis plants.

    Science.gov (United States)

    MacLean, Allyson M; Sugio, Akiko; Makarova, Olga V; Findlay, Kim C; Grieve, Victoria M; Tóth, Réka; Nicolaisen, Mogens; Hogenhout, Saskia A

    2011-10-01

    Phytoplasmas are insect-transmitted bacterial plant pathogens that cause considerable damage to a diverse range of agricultural crops globally. Symptoms induced in infected plants suggest that these phytopathogens may modulate developmental processes within the plant host. We report herein that Aster Yellows phytoplasma strain Witches' Broom (AY-WB) readily infects the model plant Arabidopsis (Arabidopsis thaliana) ecotype Columbia, inducing symptoms that are characteristic of phytoplasma infection, such as the production of green leaf-like flowers (virescence and phyllody) and increased formation of stems and branches (witches' broom). We found that the majority of genes encoding secreted AY-WB proteins (SAPs), which are candidate effector proteins, are expressed in Arabidopsis and the AY-WB insect vector Macrosteles quadrilineatus (Hemiptera; Cicadellidae). To identify which of these effector proteins induce symptoms of phyllody and virescence, we individually expressed the effector genes in Arabidopsis. From this screen, we have identified a novel AY-WB effector protein, SAP54, that alters floral development, resulting in the production of leaf-like flowers that are similar to those produced by plants infected with this phytoplasma. This study offers novel insight into the effector profile of an insect-transmitted plant pathogen and reports to our knowledge the first example of a microbial pathogen effector protein that targets flower development in a host.

  11. Meta-analytic approach to the accurate prediction of secreted virulence effectors in gram-negative bacteria

    Directory of Open Access Journals (Sweden)

    Sato Yoshiharu

    2011-11-01

    Full Text Available Abstract Background Many pathogens use a type III secretion system to translocate virulence proteins (called effectors in order to adapt to the host environment. To date, many prediction tools for effector identification have been developed. However, these tools are insufficiently accurate for producing a list of putative effectors that can be applied directly for labor-intensive experimental verification. This also suggests that important features of effectors have yet to be fully characterized. Results In this study, we have constructed an accurate approach to predicting secreted virulence effectors from Gram-negative bacteria. This consists of a support vector machine-based discriminant analysis followed by a simple criteria-based filtering. The accuracy was assessed by estimating the average number of true positives in the top-20 ranking in the genome-wide screening. In the validation, 10 sets of 20 training and 20 testing examples were randomly selected from 40 known effectors of Salmonella enterica serovar Typhimurium LT2. On average, the SVM portion of our system predicted 9.7 true positives from 20 testing examples in the top-20 of the prediction. Removal of the N-terminal instability, codon adaptation index and ProtParam indices decreased the score to 7.6, 8.9 and 7.9, respectively. These discrimination features suggested that the following characteristics of effectors had been uncovered: unstable N-terminus, non-optimal codon usage, hydrophilic, and less aliphathic. The secondary filtering process represented by coexpression analysis and domain distribution analysis further refined the average true positive counts to 12.3. We further confirmed that our system can correctly predict known effectors of P. syringae DC3000, strongly indicating its feasibility. Conclusions We have successfully developed an accurate prediction system for screening effectors on a genome-wide scale. We confirmed the accuracy of our system by external validation

  12. Identification and monitoring of effector and regulatory T cells during experimental arthritis based on differential expression of CD25 and CD134

    NARCIS (Netherlands)

    Nolte-'t Hoen, E.N.M.; Boot, E.P.J.; Wagenaar-Hilbers, J.P.A.; Bilsen, J.H.M. van; Arkesteijn, G.J.A.; Storm, G.; Everse, L.A.; Eden, W. van; Wauben, M.H.M.

    2008-01-01

    Major problems in the analysis of CD4+ effector cell and regulatory T cell (Treg) populations in an activated immune system are caused by the facts that both cell types can express CD25 and that the discriminatory marker forkhead box p3 can only be analyzed in nonviable (permeabilized) cells. Here,

  13. Differential pattern and prognostic significance of CD4+, FOXP3+ and IL-17+ tumor infiltrating lymphocytes in ductal and lobular breast cancers

    International Nuclear Information System (INIS)

    Droeser, Raoul; Zlobec, Inti; Kilic, Ergin; Güth, Uwe; Heberer, Michael; Spagnoli, Giulio; Oertli, Daniel; Tapia, Coya

    2012-01-01

    Clinical relevance of tumor infiltrating lymphocytes (TILs) in breast cancer is controversial. Here, we used a tumor microarray including a large series of ductal and lobular breast cancers with long term follow up data, to analyze clinical impact of TIL expressing specific phenotypes and distribution of TILs within different tumor compartments and in different histological subtypes. A tissue microarray (TMA) including 894 ductal and 164 lobular breast cancers was stained with antibodies recognizing CD4, FOXP3, and IL-17 by standard immunohistochemical techniques. Lymphocyte counts were correlated with clinico-pathological parameters and survival. CD4 + lymphocytes were more prevalent than FOXP3 + TILs whereas IL-17 + TILs were rare. Increased numbers of total CD4 + and FOXP3 + TIL were observed in ductal, as compared with lobular carcinomas. High grade (G3) and estrogen receptor (ER) negative ductal carcinomas displayed significantly (p < 0.001) higher CD4 + and FOXP3 + lymphocyte infiltration while her2/neu over-expression in ductal carcinomas was significantly (p < 0.001) associated with higher FOXP3 + TIL counts. In contrast, lymphocyte infiltration was not linked to any clinico-pathological parameters in lobular cancers. In univariate but not in multivariate analysis CD4 + infiltration was associated with significantly shorter survival in patients bearing ductal, but not lobular cancers. However, a FOXP3 + /CD4 + ratio > 1 was associated with improved overall survival even in multivariate analysis (p = 0.033). Ductal and lobular breast cancers appear to be infiltrated by different lymphocyte subpopulations. In ductal cancers increased CD4 + and FOXP3 + TIL numbers are associated with more aggressive tumor features. In survival analysis, absolute numbers of TILs do not represent major prognostic indicators in ductal and lobular breast cancer. Remarkably however, a ratio > 1 of total FOXP3 + /CD4 + TILs in ductal carcinoma appears to represent an independent

  14. Subtle variation within conserved effector operon gene products contributes to T6SS-mediated killing and immunity.

    Science.gov (United States)

    Alteri, Christopher J; Himpsl, Stephanie D; Zhu, Kevin; Hershey, Haley L; Musili, Ninette; Miller, Jessa E; Mobley, Harry L T

    2017-11-01

    Type VI secretion systems (T6SS) function to deliver lethal payloads into target cells. Many studies have shown that protection against a single, lethal T6SS effector protein requires a cognate antidote immunity protein, both of which are often encoded together in a two-gene operon. The T6SS and an effector-immunity pair is sufficient for both killing and immunity. HereIn this paper we describe a T6SS effector operon that differs from conventional effector-immunity pairs in that eight genes are necessary for lethal effector function, yet can be countered by a single immunity protein. In this study, we investigated the role that the PefE T6SS immunity protein plays in recognition between two strains harboring nearly identical effector operons. Interestingly, despite containing seven of eight identical effector proteins, the less conserved immunity proteins only provided protection against their native effectors, suggesting that specificity and recognition could be dependent on variation within an immunity protein and one effector gene product. The variable effector gene product, PefD, is encoded upstream from pefE, and displays toxic activity that can be countered by PefE independent of T6SS-activity. Interestingly, while the entire pef operon was necessary to exert toxic activity via the T6SS in P. mirabilis, production of PefD and PefE alone was unable to exert this effector activity. Chimeric PefE proteins constructed from two P. mirabilis strains were used to localize immunity function to three amino acids. A promiscuous immunity protein was created using site-directed mutagenesis to change these residues from one variant to another. These findings support the notion that subtle differences between conserved effectors are sufficient for T6SS-mediated kin discrimination and that PefD requires additional factors to function as a T6SS-dependent effector.

  15. Fas expression on peripheral blood lymphocytes in systemic lupus erythematosus (SLE) : relation to lymphocyte activation and disease activity

    NARCIS (Netherlands)

    Bijl, M; Horst, G; Limburg, PC; Kallenberg, CGM

    2001-01-01

    Levels of apoptotic lymphocytes have been found to be increased in SLE and persistence of apoptotic cells has been associated with autoantibody production, Increased lymphocyte Fas (CD95) expression due to lymphocyte activation may account for increased Susceptibility to Fas-mediated apoptosis in

  16. Interleukin-33 promoting Th1 lymphocyte differentiation dependents on IL-12.

    Science.gov (United States)

    Komai-Koma, Mousa; Wang, Eryi; Kurowska-Stolarska, Mariola; Li, Dong; McSharry, Charles; Xu, Damo

    2016-03-01

    The pro-Th2 cytokine IL-33 is now emerging as an important Th1 cytokine-IFN-γ inducer in murine CD4(+) T cells that is essential for protective cell-mediated immunity against viral infection in mice. However, whether IL-33 can promote human Th1 cell differentiation and how IL-33 polarizes Th1 cells is less understood. We assessed the ability of IL-33 to induce Th1 cell differentiation and IFN-γ production in vitro and in vivo. We report here that IL-33 alone had no ability in Th1 cell polarization. However it potentiated IL-12-mediated Th1 cell differentiation and IFN-γ production in TCR-stimulated murine and human CD4(+) T cells in vitro and in vivo. IL-33 promoted Th1 cell development via MyD88 and synergized with IL-12 to enhance St2 and IL-12R expression in CD4(+) T cells. These data therefore provide a novel mechanism for Th1 cell differentiation and optimal induction of a Type 1 response. Thus, IL-33 is capable of inducing IL-12-dependent Th1 cell differentiation in human and mouse CD4(+) T cells. Copyright © 2015 The Authors. Published by Elsevier GmbH.. All rights reserved.

  17. Direct anti-inflammatory effects of granulocyte colony-stimulating factor (G-CSF) on activation and functional properties of human T cell subpopulations in vitro.

    Science.gov (United States)

    Malashchenko, Vladimir Vladimirovich; Meniailo, Maxsim Evgenievich; Shmarov, Viacheslav Anatolievich; Gazatova, Natalia Dinislamovna; Melashchenko, Olga Borisovna; Goncharov, Andrei Gennadievich; Seledtsova, Galina Victorovna; Seledtsov, Victor Ivanovich

    2018-03-01

    We investigated the direct effects of human granulocyte colony-stimulating factor (G-CSF) on functionality of human T-cell subsets. CD3 + T-lymphocytes were isolated from blood of healthy donors by positive magnetic separation. T cell activation with particles conjugated with antibodies (Abs) to human CD3, CD28 and CD2 molecules increased the proportion of cells expressing G-CSF receptor (G-CSFR, CD114) in all T cell subpopulations studied (CD45RA + /CD197 + naive T cells, CD45RA - /CD197 + central memory T cells, CD45RA - /CD197 - effector memory T cells and CD45RA + /CD197 - terminally differentiated effector T cells). Upon T-cell activation in vitro, G-CSF (10.0 ng/ml) significantly and specifically enhanced the proportion of CD114 + T cells in central memory CD4 + T cell compartment. A dilution series of G-CSF (range, 0.1-10.0 ng/ml) was tested, with no effect on the expression of CD25 (interleukin-2 receptor α-chain) on activated T cells. Meanwhile, G-CSF treatment enhanced the proportion of CD38 + T cells in CD4 + naïve T cell, effector memory T cell and terminally differentiated effector T cell subsets, as well as in CD4 - central memory T cells and terminally differentiated effector T cells. G-CSF did not affect IL-2 production by T cells; relatively low concentrations of G-CSF down-regulated INF-γ production, while high concentrations of this cytokine up-regulated IL-4 production in activated T cells. The data obtained suggests that G-CSF could play a significant role both in preventing the development of excessive and potentially damaging inflammatory reactivity, and in constraining the expansion of potentially cytodestructive T cells. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. AID protein expression in chronic lymphocytic leukemia/small lymphocytic lymphoma is associated with poor prognosis and complex genetic alterations.

    Science.gov (United States)

    Leuenberger, Mona; Frigerio, Simona; Wild, Peter J; Noetzli, Franziska; Korol, Dimitri; Zimmermann, Dieter R; Gengler, Carole; Probst-Hensch, Nicole M; Moch, Holger; Tinguely, Marianne

    2010-02-01

    The biological behavior of chronic lymphocytic leukemia and small lymphocytic lymphoma is unpredictable. Nonetheless, non-mutated IgV(H) gene rearrangement, ATM (11q22-23) and p53 (17p13) deletion are recognized as unfavorable prognosticators in chronic lymphocytic leukemia. The mRNA expression of activation-induced cytidine deaminase (AID), an enzyme indispensable for somatic hypermutation processes, was claimed to be predictive of non-mutated chronic lymphocytic leukemia cells in blood. Here, we evaluated AID protein expression compared with known molecular and immunohistochemical prognostic indicators in 71 chronic lymphocytic leukemia/small lymphocytic lymphoma patients using a tissue microarray approach. We found AID heterogeneously expressed in tumor cells as shown by colocalization analysis for CD5 and CD23. Ki-67 positive paraimmunoblasts of the proliferation centers displayed the highest expression. This observation is reflected by a significant association of AID positivity with a high proliferation rate (P=0.012). ATM deletion was detected in 10% (6/63) of patients and p53 deletion in 19% (13/67) of patients. Moreover, both ATM (P=0.002) and p53 deletion (P=0.004) were significantly associated with AID. IgV(H) gene mutation was seen in 45% (27/60) of patients. Twenty-five percent (17/69) of patients with AID-positive chronic lymphocytic leukemia/small lymphocytic lymphoma displayed a shorter survival than AID-negative chronic lymphocytic leukemia/small lymphocytic lymphoma patients (61 vs 130 months, P=0.001). Although there was a trend, we could not show an association with the IgV(H) gene mutation status. Taken together, our study shows that AID expression is an indicator of an unfavorable prognosis in chronic lymphocytic leukemia/small lymphocytic lymphoma patients, although it is not a surrogate marker for the IgV(H) status. Furthermore, the microenvironment of proliferation centers seems to influence AID regulation and might be an initiating factor

  19. Organ distribution of 111In-oxine labeled lymphocytes in normal subjects and in patients with chronic lymphocytic leukemia and malignant lymphoma

    International Nuclear Information System (INIS)

    Matsuda, Shin; Uchida, Tatsumi; Yui, Tokuo; Kariyone, Shigeo

    1982-01-01

    T and B lymphocyte survival and organ distribution were studied by using 111 In-oxine labeled autologous lymphocytes in 3 normal subjects, 3 patients with chronic lymphocytic leukemia (CLL) and 9 with malignant lymphoma (ML).FDisappearance curves of the labeled lymphocytes showed two exponential components in all cases. The half time of the first component was within 1 hour in all cases. That of the second one was 50.7 +- 6.4 hours for all lymphocytes, 52.0 +- 5.5 hours for T lymphocytes and 31.6 +- 4.9 hours for B lymphocytes in normal subjects, 192.6 hours for T-CLL and 57.7 +- 46.9 hours for B-CLL, and 60.2 +- 30.7 hours for T cell type of malignant lymphoma (T-ML) and 63.7 +- 24.5 hours for B cell type of malignant lymphoma (B-ML). These data might suggest that all lymphocyte disappearance curve reflected T lymphocyte disappearance curve chiefly, and the half time of B lymphocytes was shorter than that of T lymphocytes. In the T-CLL, the half time of the second component prolonged extremely in comparison with that of normal T lymphocytes. The labeled cells were accumulated in the lungs, spleen and liver immediately after the infusion, then in the spleen most remarkably 1 hour after the infusion in all cases. The radioactivity over the bone marrow was observed from 1 hour in all cases and that of lymph nodes were first noticed 18 hours after the infusion in T-CLL and T-ML, 68 hours in B-CLL but were not noticed in normal subjects and B-ML. The recovery of labeled cells in the blood was 28.5 +- 7.9% for all lymphocytes, 19.7 +- 1.9% for T lymphocytes and 11.0 +- 5.1% for B lymphocytes in normal subjects, 25.8 +- 1.6% for CLL, and 17.6 +- 11.0% for T-ML, 7.7 +- 5.2% for B-ML, respectively. (J.P.N.)

  20. Innate B cells: oxymoron or validated concept? [v1; ref status: indexed, http://f1000r.es/T4CAVP

    Directory of Open Access Journals (Sweden)

    Carl F Ware

    2012-08-01

    Full Text Available B lymphocytes promote the initial innate interferon response to viral pathogens without the need for antigen receptor activation. B cell dependent IFN production requires the cytokine, lymphotoxin-β. The LTβ pathway is well known to regulate lymphoid organogenesis and homeostasis by differentiating stromal cells and macrophages. However, in response to viral pathogens these same B cell-regulated populations rapidly produce type 1 interferons. Thus, B cells act as innate effector cells via LTβ homeostatic pathways, which serve as innate host barriers to viral pathogens.

  1. Hypercalcaemia associated with chronic lymphocytic leukaemia in a Giant Schnauzer.

    Science.gov (United States)

    Kleiter, M; Hirt, R; Kirtz, G; Day, M J

    2001-05-01

    A 7-year-old male Giant Schnauzer was referred with a history of severe vomiting, lethargy, weight loss, polydipsia and polyuria. Detailed investigations revealed leucocytosis with a marked lymphocytosis, mild non-regenerative anaemia, thrombocytopenia, hypercalcaemia and azotaemia. Circulating lymphocytes were small and well-differentiated, and the same lymphoid population was present in bone marrow. Chronic lymphocyctic leukaemia with associated paraneoplastic hypercalcaemia was diagnosed. Immunohistochemical staining of a bone marrow biopsy revealed a neoplastic B-cell line expressing CD79. The dog responded to therapy with prednisolone and chlorambucil for a period of 8 months.

  2. Immune Reactions Against Elongation Factor 2 Kinase: Specific Pathogenesis of Gastric Ulcer from Helicobacter pylori Infection

    Directory of Open Access Journals (Sweden)

    Kiyoshi Ayada

    2009-01-01

    Full Text Available Helicobacter pylori (H. pylori infection is a definite causative factor for gastric ulcers (GUs. In the present study we detected a specific antigen of gastric epithelial cells (HGC-27 using cell ELISA, which was recognized by the sera of GU patients (n=20 but not in patients with chronic gastritis (CG; n=20 or in healthy volunteers (HC; n=10. This antigen was over-expressed by a stressful (heat-stressed environment, and was identified as elongation factor 2 kinase (EF-2K by western blotting. The GU patients' lymphocytes stimulated by H. pylori specifically disrupted heat-stressed HGC-27 cells in a cytotoxic assay. In flow cytometry, the effector cells (lymphocytes from GU patients were significantly differentiated to T helper type 1 lymphocyte (Th1 and cytotoxic T lymphocyte (CTL as opposed to those from CG patients. The target cells (HGC-27 expressed EF-2K and MHC-class I together with costimulatory molecules from heat stress. This antigen specific immune mechanism could have a prominent role in the pathogenesis of GU.

  3. Dimethyl Sulfoxide (DMSO) Decreases Cell Proliferation and TNF-α, IFN-γ, and IL-2 Cytokines Production in Cultures of Peripheral Blood Lymphocytes.

    Science.gov (United States)

    de Abreu Costa, Lucas; Henrique Fernandes Ottoni, Marcelo; Dos Santos, Michaelle Geralda; Meireles, Agnes Batista; Gomes de Almeida, Valéria; de Fátima Pereira, Wagner; Alves de Avelar-Freitas, Bethânia; Eustáquio Alvim Brito-Melo, Gustavo

    2017-11-10

    Dimethylsulfoxide (DMSO) is an amphipathic molecule composed of a polar domain characterized by the sulfinyl and two nonpolar methyl groups, for this reason it is able to solubilize polar and nonpolar substances and transpose hydrophobic barriers. DMSO is widely used to solubilize drugs of therapeutic applications and studies indicated that 10% v/v concentration did not modify culture viability when used to treat human peripheral blood mononuclear cells (PBMC). However, some DMSO concentrations could influence lymphocyte activation and present anti-inflammatory effects. Therefore, the objective of this study was to evaluate the effect of DMSO on lymphocyte activation parameters. Cell viability analysis, proliferation, and cytokine production were performed on PBMC from six healthy subjects by flow cytometry. The results indicated that 2.5% v/v DMSO concentrations did not modify lymphocytes viability. DMSO at 1% and 2% v/v concentrations reduced the relative proliferation index of lymphocytes and at 5% and 10% v/v concentrations reduced the percentage of total lymphocytes, cluster of differentiation 4⁺ (CD4⁺) T lymphocytes and CD8⁺ T lymphocytes interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α) and interleukin-2 (IL-2) producers. Thus, it was concluded that DMSO has an in vitro anti-inflammatory effect by reducing lymphocyte activation demonstrated with proliferation reduction and the decrease of cytokine production.

  4. Inhibitory effects of various oxygenated sterols on the differentiation and function of tumor-specific cytotoxic T lymphocytes

    International Nuclear Information System (INIS)

    Spangrude, G.J.; Sherris, D.; Daynes, R.A.

    1982-01-01

    Irradiation of skin with ultraviolet light (UVL) is capable of causing many biological and biochemical changes in this complex organ. One early consequence is the oxidation of epidermal plasma membrane cholesterol, causing the induction of a wide variety of photoproducts. It is well recognized that some oxygenated sterols possess potent biological activity on mammalian cells by their ability to inhibit endogeneous mevalonate and cholesterol biosynthesis. In the few immunological systems that have been studied, there is general agreement that lymphocyte function is lacking, as both afferent and efferent blockades have been suggested. These studies were undertaken to determine the effect of various oxygenated sterols (representing a number of known cholesterol-derived photoproducts) on the generation (afferent) and function (efferent) of cytotoxic T lymphocytes (CTLs). Cell-mediated immune responses which result in the generation of both alloantigen-specific and syngeneic tumor-specific CTLs were evaluated

  5. Pre-malignant lymphoid cells arise from hematopoietic stem/progenitor cells in chronic lymphocytic leukemia.

    Science.gov (United States)

    Kikushige, Yoshikane; Miyamoto, Toshihiro

    2015-11-01

    Human malignancies progress through a multistep process that includes the development of critical somatic mutations over the clinical course. Recent novel findings have indicated that hematopoietic stem cells (HSCs), which have the potential to self-renew and differentiate into multilineage hematopoietic cells, are an important cellular target for the accumulation of critical somatic mutations in hematological malignancies and play a central role in myeloid malignancy development. In contrast to myeloid malignancies, mature lymphoid malignancies, such as chronic lymphocytic leukemia (CLL), are thought to originate directly from differentiated mature lymphocytes; however, recent compelling data have shown that primitive HSCs and hematopoietic progenitor cells contribute to the pathogenesis of mature lymphoid malignancies. Several representative mutations of hematological malignancies have been identified within the HSCs of CLL and lymphoma patients, indicating that the self-renewing long-lived fraction of HSCs can serve as a reservoir for the development of oncogenic events. Novel mice models have been established as human mature lymphoma models, in which specific oncogenic events target the HSCs and immature progenitor cells. These data collectively suggest that HSCs can be the cellular target involved in the accumulation of oncogenic events in the pathogenesis of mature lymphoid and myeloid malignancies.

  6. Radiosensitivity of lymphocytes in vitro

    International Nuclear Information System (INIS)

    Albrecht, S.

    1979-01-01

    The radiation-induced impairment of human T-lymphocytes was studied after in vitro exposure to 25.8 - 825.6 mC/kg (100 - 3200 R) of 60 Co γ-radiation by ascertaining the change in lymphocyte response to phytohaemagglutin stimulation. Following methods were used: (1) measurement of 3 H-thymidine uptake, (2) E-rosette test, and (3) morphological examination of transformed T-cells. The results revealed a dose-dependent decline in T-cell number which was still somewhat more marked with lymphocytes purified over Ficoll-Isopaque prior to irradiation. (author)

  7. Immunoregulatory effects on T lymphocytes by human mesenchymal stromal cells isolated from bone marrow, amniotic fluid, and placenta.

    Science.gov (United States)

    Mareschi, Katia; Castiglia, Sara; Sanavio, Fiorella; Rustichelli, Deborah; Muraro, Michela; Defedele, Davide; Bergallo, Massimiliano; Fagioli, Franca

    2016-02-01

    Mesenchymal stromal cells (MSCs) are a promising tool in cell therapies because of their multipotent, bystander, and immunomodulatory properties. Although bone marrow represents the main source of MSCs, there remains a need to identify a stem cell source that is safe and easily accessible and yields large numbers of cells without provoking debates over ethics. In this study, MSCs isolated from amniotic fluid and placenta were compared with bone marrow MSCs. Their immunomodulatory properties were studied in total activated T cells (peripheral blood mononuclear cells) stimulated with phytohemagglutinin (PHA-PBMCs). In particular, an in vitro co-culture system was established to study: (i) the effect on T-lymphocyte proliferation; (ii) the presence of T regulatory lymphocytes (Treg); (iii) the immunophenotype of various T subsets (Th1 and Th2 naïve, memory, effector lymphocytes); (iv) cytokine release and master gene expression to verify Th1, Th2, and Th17 polarization; and (v) IDO production. Under all co-culture conditions with PHA-PBMCs and MSCs (independently of tissue origin), data revealed: (i) T proliferation inhibition; (ii) increase in naïve T and decrease in memory T cells; (iii) increase in T regulatory lymphocytes; (iv) strong Th2 polarization associated with increased interleukin-10 and interleukin-4 levels, Th1 inhibition (significant decreases in interleukin-2, tumor necrosis factor-α, interferon-γ, and interleukin-12) and Th17 induction (production of high concentrations of interleukins-6 and -17); (v) indoleamine-2,3-dioxygenase mRNA induction in MSCs co-cultured with PHA-PBMCs. AF-MSCs had a more potent immunomodulatory effect on T cells than BM-MSCs, only slightly higher than that of placenta MSCs. This study indicates that MSCs isolated from fetal tissues may be considered a good alternative to BM-MSCs for clinical applications. Copyright © 2016 ISEH - International Society for Experimental Hematology. Published by Elsevier Inc. All rights

  8. Functions and requirements for the INEL light duty utility arm gripper end effector

    International Nuclear Information System (INIS)

    Pace, D.P.; Barnes, G.E.

    1995-02-01

    This gripper end effector system functions and requirements document defines the system functions that the end effector must perform as well as the requirements the design must meet. Safety, quality assurance, operations, environmental conditions, and regulatory requirements have been considered. The main purpose of this document is to provide a basis for the end effector engineering, design, and fabrication activities. The document shall be the living reference document to initiate the development activities and will be updated as system technologies are finalized

  9. Functions and requirements for the INEL light duty utility arm sampler end effector

    International Nuclear Information System (INIS)

    Pace, D.P.; Barnes, G.E.

    1995-02-01

    This sampler end effector system functions and requirements document defines the system functions that the end effector must perform as well as the requirements the design must meet. Safety, quality assurance, operations, environmental conditions, and regulatory requirements have been considered. The main purpose of this document is to provide a basis for the end effector engineering, design, and fabrication activities. The document shall be the living reference document to initiate the development activities and will be updated as system technologies are finalized

  10. Establishment of an inducing medium for type III effector secretion in Xanthomonas campestris pv. campestris

    Directory of Open Access Journals (Sweden)

    Guo-Feng Jiang

    2013-09-01

    Full Text Available It is well known that the type III secretion system (T3SS and type III (T3 effectors are essential for the pathogenicity of most bacterial phytopathogens and that the expression of T3SS and T3 effectors is suppressed in rich media but induced in minimal media and plants. To facilitate in-depth studies on T3SS and T3 effectors, it is crucial to establish a medium for T3 effector expression and secretion. Xanthomonas campestris pv. campestris (Xcc is a model bacterium for studying plant-pathogen interactions. To date no medium for Xcc T3 effector secretion has been defined. Here, we compared four minimal media (MME, MMX, XVM2, and XOM2 which are reported for T3 expression induction in Xanthomonas spp. and found that MME is most efficient for expression and secretion of Xcc T3 effectors. By optimization of carbon and nitrogen sources and pH value based on MME, we established XCM1 medium, which is about 3 times stronger than MME for Xcc T3 effectors secretion. We further optimized the concentration of phosphate, calcium, and magnesium in XCM1 and found that XCM1 with a lower concentration of magnesium (renamed as XCM2 is about 10 times as efficient as XCM1 (meanwhile, about 30 times stronger than MME. Thus, we established an inducing medium XCM2 which is preferred for T3 effector secretion in Xcc.

  11. Differentiation of human umbilical cord mesenchymal stromal cells into low immunogenic hepatocyte-like cells.

    Science.gov (United States)

    Zhao, Qinjun; Ren, Hongying; Li, Xiyuan; Chen, Zhong; Zhang, Xiangyu; Gong, Wei; Liu, Yongjun; Pang, Tianxiang; Han, Zhong Chao

    2009-01-01

    Mesenchymal stromal cells (MSC) isolated from several human tissues have been known to differentiate into the hepatic lineage in vitro, but the immunogenicity of the differentiated hepatocyte-like cells (DHC) has not been reported. Umbilical cord (UC) MSC are thought to be an attractive cell source for cell therapy because of their young age and low infection rate compared with adult tissue MSC. Hepatic differentiation of UC-MSC was induced with a 2-step protocol. The expressions of hepatic markers were detected by RT-PCR and immunofluorescence staining. Albumin production and urea secretion were measured by ELISA and colorimetric assay respectively. The immunosuppressive properties of DHC was detected by mixed lymphocyte culture. After incubation with specific growth factors, including hepatocyte growth factor (HGF) and basic fibroblast growth factor (bFGF), UC MSC exhibited a high hepatic differentiation ability in an adherent culture condition. The differentiated UC MSC showed hepatocyte-like morphology and expressed several liver-specific markers at gene and protein levels. Furthermore, the DHC exhibited hepatocyte-specific functions, including albumin secretion, low-density lipoprotein uptake and urea production. More importantly, DHC did not express major histocompatibility complex (MHC) II antigen and were not able to induce lymphocyte proliferation in mixed lymphocyte culture, as undifferentiated UC MSC did. Our results indicate that UC MSC are able to differentiate into functional hepatocyte-like cells that still retain their low immunogenicity in vitro. More importantly, DHC incorporated into the parenchyma of liver when transplanted into mice with CCl(4)-induced liver injury. Therefore, DHC may be an ideal source for cell therapy of liver diseases.

  12. The Legionella pneumophila IcmSW complex interacts with multiple Dot/Icm effectors to facilitate type IV translocation.

    Directory of Open Access Journals (Sweden)

    Eric D Cambronne

    2007-12-01

    Full Text Available Many gram-negative pathogens use a type IV secretion system (T4SS to deliver effector proteins into eukaryotic host cells. The fidelity of protein translocation depends on the efficient recognition of effector proteins by the T4SS. Legionella pneumophila delivers a large number of effector proteins into eukaryotic cells using the Dot/Icm T4SS. How the Dot/Icm system is able to recognize and control the delivery of effectors is poorly understood. Recent studies suggest that the IcmS and IcmW proteins interact to form a stable complex that facilitates translocation of effector proteins by the Dot/Icm system by an unknown mechanism. Here we demonstrate that the IcmSW complex is necessary for the productive translocation of multiple Dot/Icm effector proteins. Effector proteins that were able to bind IcmSW in vitro required icmS and icmW for efficient translocation into eukaryotic cells during L. pneumophila infection. We identified regions in the effector protein SidG involved in icmSW-dependent translocation. Although the full-length SidG protein was translocated by an icmSW-dependent mechanism, deletion of amino terminal regions in the SidG protein resulted in icmSW-independent translocation, indicating that the IcmSW complex is not contributing directly to recognition of effector proteins by the Dot/Icm system. Biochemical and genetic studies showed that the IcmSW complex interacts with a central region of the SidG protein. The IcmSW interaction resulted in a conformational change in the SidG protein as determined by differences in protease sensitivity in vitro. These data suggest that IcmSW binding to effectors could enhance effector protein delivery by mediating a conformational change that facilitates T4SS recognition of a translocation domain located in the carboxyl region of the effector protein.

  13. Identification and characterisation of a hyper-variable apoplastic effector gene family of the potato cyst nematodes.

    Science.gov (United States)

    Eves-van den Akker, Sebastian; Lilley, Catherine J; Jones, John T; Urwin, Peter E

    2014-09-01

    Sedentary endoparasitic nematodes are obligate biotrophs that modify host root tissues, using a suite of effector proteins to create and maintain a feeding site that is their sole source of nutrition. Using assumptions about the characteristics of genes involved in plant-nematode biotrophic interactions to inform the identification strategy, we provide a description and characterisation of a novel group of hyper-variable extracellular effectors termed HYP, from the potato cyst nematode Globodera pallida. HYP effectors comprise a large gene family, with a modular structure, and have unparalleled diversity between individuals of the same population: no two nematodes tested had the same genetic complement of HYP effectors. Individuals vary in the number, size, and type of effector subfamilies. HYP effectors are expressed throughout the biotrophic stages in large secretory cells associated with the amphids of parasitic stage nematodes as confirmed by in situ hybridisation. The encoded proteins are secreted into the host roots where they are detectable by immunochemistry in the apoplasm, between the anterior end of the nematode and the feeding site. We have identified HYP effectors in three genera of plant parasitic nematodes capable of infecting a broad range of mono- and dicotyledon crop species. In planta RNAi targeted to all members of the effector family causes a reduction in successful parasitism.

  14. UDS and SCE in lymphocytes of persons occupationally exposed to low levels of ionizing radiation

    International Nuclear Information System (INIS)

    Tuschl, H.; Kovac, R.; Altmann, H.

    1983-03-01

    Unscheduled DNA synthesis induced by 'in vitro' UV-irradiation was investigated in lymphocytes of persons occupationally exposed to low doses of ionizing radiation (maximum registered radiation dose: 98 mrad/month). For radiation exposures >14 mrad/month, above background level, increased rates of UDS after in vitro UV-irradiation of lymphocytes were found. The bromodeoxyuridine differential chromatid labeling technique was applied to the examination of spontaneous and mytomycin C induced sister chromatid exchanges in the same population. No statistically significant difference could be determined in spontaneously occurring SCEs, while MMC induced SCEs were significantly reduced in persons exposed to radiation doses >14 mrad/month, thus indicating increased repair capability for DNA lesions inflicted by a second insult after protracted low dose irradiation. (Author) [de

  15. Gamma delta T-cell differentiation and effector function programming, TCR signal strength, when and how much?

    Science.gov (United States)

    Zarin, Payam; Chen, Edward L Y; In, Tracy S H; Anderson, Michele K; Zúñiga-Pflücker, Juan Carlos

    2015-07-01

    γδ T-cells boast an impressive functional repertoire that can paint them as either champions or villains depending on the environmental and immunological cues. Understanding the function of the various effector γδ subsets necessitates tracing the developmental program of these subsets, including the point of lineage bifurcation from αβ T-cells. Here, we review the importance of signals from the T-cell receptor (TCR) in determining αβ versus γδ lineage fate, and further discuss how the molecular components of this pathway may influence the developmental programming of γδ T-cells functional subsets. Additionally, we discuss the role of temporal windows in restricting the development of IL-17 producing γδ T-cell subtypes, and explore whether fetal and adult hematopoietic progenitors maintain the same potential for giving rise to this important subset. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Effector-independent motor sequence representations exist in extrinsic and intrinsic reference frames.

    Science.gov (United States)

    Wiestler, Tobias; Waters-Metenier, Sheena; Diedrichsen, Jörn

    2014-04-02

    Many daily activities rely on the ability to produce meaningful sequences of movements. Motor sequences can be learned in an effector-specific fashion (such that benefits of training are restricted to the trained hand) or an effector-independent manner (meaning that learning also facilitates performance with the untrained hand). Effector-independent knowledge can be represented in extrinsic/world-centered or in intrinsic/body-centered coordinates. Here, we used functional magnetic resonance imaging (fMRI) and multivoxel pattern analysis to determine the distribution of intrinsic and extrinsic finger sequence representations across the human neocortex. Participants practiced four sequences with one hand for 4 d, and then performed these sequences during fMRI with both left and right hand. Between hands, these sequences were equivalent in extrinsic or intrinsic space, or were unrelated. In dorsal premotor cortex (PMd), we found that sequence-specific activity patterns correlated higher for extrinsic than for unrelated pairs, providing evidence for an extrinsic sequence representation. In contrast, primary sensory and motor cortices showed effector-independent representations in intrinsic space, with considerable overlap of the two reference frames in caudal PMd. These results suggest that effector-independent representations exist not only in world-centered, but also in body-centered coordinates, and that PMd may be involved in transforming sequential knowledge between the two. Moreover, although effector-independent sequence representations were found bilaterally, they were stronger in the hemisphere contralateral to the trained hand. This indicates that intermanual transfer relies on motor memories that are laid down during training in both hemispheres, but preferentially draws upon sequential knowledge represented in the trained hemisphere.

  17. Common-Lymphoid-Progenitor-Independent Pathways of Innate and T Lymphocyte Development

    Directory of Open Access Journals (Sweden)

    Maryam Ghaedi

    2016-04-01

    Full Text Available All lymphocytes are thought to develop from common lymphoid progenitors (CLPs. However, lymphoid-primed multipotent progenitors (LMPPs are more efficient than CLPs in differentiating into T cells and group 2 innate lymphoid cells (ILC2s. Here, we have divided LMPPs into CD127− (LMPP−s and CD127+ (LMPP+s subsets and compared them with Ly6D− and Ly6D+ CLPs. Adult LMPP+s differentiated into T cells and ILCs more rapidly and efficiently than other progenitors in transplantation assays. The development of T cells and ILC2s is highly active in the neonatal period. Neonatal CLPs are rare and, unlike prominent neonatal LMPP+s, do not efficiently differentiate into T cells and ILC2s. ILC2s generated in the neonatal period are long lived and persist in adult tissues. These results suggest that some ILCs and T cells may develop from LMPP+s via CLP-independent pathways.

  18. Chemokines, lymphocytes, and HIV

    Directory of Open Access Journals (Sweden)

    Farber J.M.

    1998-01-01

    Full Text Available Chemokines are members of a family of more than 30 human cytokines whose best-described activities are as chemotactic factors for leukocytes and that are presumed to be important in leukocyte recruitment and trafficking. While many chemokines can act on lymphocytes, the roles of chemokines and their receptors in lymphocyte biology are poorly understood. The recent discoveries that chemokines can suppress infection by HIV-1 and that chemokine receptors serve, along with CD4, as obligate co-receptors for HIV-1 entry have lent urgency to studies on the relationships between chemokines and lymphocytes. My laboratory has characterized Mig and Crg-2/IP-10, chemokines that are induced by IFN-g and that specifically target lymphocytes, particularly activated T cells. We have demonstrated that the genes for these chemokines are widely expressed during experimental infections in mice with protozoan and viral pathogens, but that the patterns of mig and crg-2 expression differed, suggesting non-redundant roles in vivo. Our related studies to identify new chemokine receptors from activated lymphocytes resulted in the cloning of STRL22 and STRL33. We and others have shown that STRL22 is a receptor for the CC chemokine MIP-3a, and STRL22 has been re-named CCR6. Although STRL33 remains an orphan receptor, we have shown that it can function as a co-receptor for HIV-1 envelope glycoproteins, and that it is active with a broader range of HIV-1 envelope glycoproteins than the major co-receptors described to date. The ability of STRL33 to function with a wide variety of envelope glycoproteins may become particularly important if therapies are instituted to block other specific co-receptors. We presume that investigations into the roles of chemokines and their receptors in lymphocyte biology will provide information important for understanding the pathogenesis of AIDS and for manipulating immune and inflammatory responses for clinical benefit

  19. Natural killer activity of peripheral blood lymphocytes in patients with brain tumors

    International Nuclear Information System (INIS)

    Otsuka, Shin-ichi; Suda, Kinya; Yamashita, Junkoh; Takeuchi, Juji; Handa, Hajime

    1982-01-01

    Natural killer activity (NK activity) of peripheral blood ymphocytes in patients with brain tumors was examined by the method of 51 Cr release assay in order to study the effects of operation and radiotherapy on the immunological activity of the hosts. NK activity of peripheral blood lymphocytes in normal persons was about 50 to 70% and about 30 to 50% (% specific 51 Cr release) at a ratio of target to effector cells of 1 : 25 and 1 : 12.5 respectively. There were no significant differences in NK activity in regard to the histological types of brain tumors. As for the effects of operation on NK activity, NK activity decreased by the end of the 1st week after operation and then increased gradually and returned to the pre-operative level 2 to 3 weeks after operation. The causes of decrease of NK activity after operation are not clear but there are some factors to be considered, such as bleeding during operation, non-specific inflammation, use of steroid after operation and the decrease of the stimulation of tumor antigen. As regards the effects of radiotherapy on NK activity, NK activity increased within 3 weeks after the beginning of radiotherapy. The increase of NK activity may indicate that the immunological resistance to tumor was enhanced in hosts by local irradiation of the tumor. Some characteristics of the effector cells were examined. E rosette non-forming cells had a stronger cytoxicity against target cells than E rosette forming cells. Nylon wool non-adherent cells had slightly higher cytotoxicity than adherent cells but the cytotoxicity was recognized in both fractions. It is felt important to clarify further the clinical significance of changes of NK activity in relation to various treatments and prognosis in patients with brain tumors. (author)

  20. SHARPIN Regulates Uropod Detachment in Migrating Lymphocytes

    Directory of Open Access Journals (Sweden)

    Jeroen Pouwels

    2013-11-01

    Full Text Available SHARPIN-deficient mice display a multiorgan chronic inflammatory phenotype suggestive of altered leukocyte migration. We therefore studied the role of SHARPIN in lymphocyte adhesion, polarization, and migration. We found that SHARPIN localizes to the trailing edges (uropods of both mouse and human chemokine-activated lymphocytes migrating on intercellular adhesion molecule-1 (ICAM-1, which is one of the major endothelial ligands for migrating leukocytes. SHARPIN-deficient cells adhere better to ICAM-1 and show highly elongated tails when migrating. The increased tail lifetime in SHARPIN-deficient lymphocytes decreases the migration velocity. The adhesion, migration, and uropod defects in SHARPIN-deficient lymphocytes were rescued by reintroducing SHARPIN into the cells. Mechanistically, we show that SHARPIN interacts directly with lymphocyte-function-associated antigen-1 (LFA-1, a leukocyte counterreceptor for ICAM-1, and inhibits the expression of intermediate and high-affinity forms of LFA-1. Thus, SHARPIN controls lymphocyte migration by endogenously maintaining LFA-1 inactive to allow adjustable detachment of the uropods in polarized cells.

  1. Identification of proteins similar to AvrE type III effector proteins from ...

    African Journals Online (AJOL)

    Type III effector proteins are injected into host cells through type III secretion systems. Some effectors are similar to host proteins to promote pathogenicity, while others lead to the activation of disease resistance. We used partial least squares alignment-free bioinformatics methods to identify proteins similar to AvrE proteins ...

  2. Shigella IpaH Family Effectors as a Versatile Model for Studying Pathogenic Bacteria.

    Science.gov (United States)

    Ashida, Hiroshi; Sasakawa, Chihiro

    2015-01-01

    Shigella spp. are highly adapted human pathogens that cause bacillary dysentery (shigellosis). Via the type III secretion system (T3SS), Shigella deliver a subset of virulence proteins (effectors) that are responsible for pathogenesis, with functions including pyroptosis, invasion of the epithelial cells, intracellular survival, and evasion of host immune responses. Intriguingly, T3SS effector activity and strategies are not unique to Shigella, but are shared by many other bacterial pathogens, including Salmonella, Yersinia, and enteropathogenic Escherichia coli (EPEC). Therefore, studying Shigella T3SS effectors will not only improve our understanding of bacterial infection systems, but also provide a molecular basis for developing live bacterial vaccines and antibacterial drugs. One of Shigella T3SS effectors, IpaH family proteins, which have E3 ubiquitin ligase activity and are widely conserved among other bacterial pathogens, are very relevant because they promote bacterial survival by triggering cell death and modulating the host immune responses. Here, we describe selected examples of Shigella pathogenesis, with particular emphasis on the roles of IpaH family effectors, which shed new light on bacterial survival strategies and provide clues about how to overcome bacterial infections.

  3. Shigella IpaH family effectors as a versatile model for studying pathogenic bacteria

    Directory of Open Access Journals (Sweden)

    Hiroshi eAshida

    2016-01-01

    Full Text Available Shigella spp. are highly adapted human pathogens that cause bacillary dysentery (shigellosis. Via the type III secretion system (T3SS, Shigella deliver a subset of virulence proteins (effectors that are responsible for pathogenesis, with functions including pyroptosis, invasion of the epithelial cells, intracellular survival, and evasion of host immune responses. Intriguingly, T3SS effector activity and strategies are not unique to Shigella, but are shared by many other bacterial pathogens, including Salmonella, Yersinia, and enteropathogenic Escherichia coli (EPEC. Therefore, studying Shigella T3SS effectors will not only improve our understanding of bacterial infection systems, but also provide a molecular basis for developing live bacterial vaccines and antibacterial drugs. One of Shigella T3SS effectors, IpaH family proteins, which have E3 ubiquitin ligase activity and are widely conserved among other bacterial pathogens, are very relevant because they promote bacterial survival by triggering cell death and modulating the host immune responses. Here, we describe selected examples of Shigella pathogenesis, with particular emphasis on the roles of IpaH family effectors, which shed new light on bacterial survival strategies and provide clues about how to overcome bacterial infections.

  4. Using hierarchical clustering of secreted protein families to classify and rank candidate effectors of rust fungi.

    Directory of Open Access Journals (Sweden)

    Diane G O Saunders

    Full Text Available Rust fungi are obligate biotrophic pathogens that cause considerable damage on crop plants. Puccinia graminis f. sp. tritici, the causal agent of wheat stem rust, and Melampsora larici-populina, the poplar leaf rust pathogen, have strong deleterious impacts on wheat and poplar wood production, respectively. Filamentous pathogens such as rust fungi secrete molecules called disease effectors that act as modulators of host cell physiology and can suppress or trigger host immunity. Current knowledge on effectors from other filamentous plant pathogens can be exploited for the characterisation of effectors in the genome of recently sequenced rust fungi. We designed a comprehensive in silico analysis pipeline to identify the putative effector repertoire from the genome of two plant pathogenic rust fungi. The pipeline is based on the observation that known effector proteins from filamentous pathogens have at least one of the following properties: (i contain a secretion signal, (ii are encoded by in planta induced genes, (iii have similarity to haustorial proteins, (iv are small and cysteine rich, (v contain a known effector motif or a nuclear localization signal, (vi are encoded by genes with long intergenic regions, (vii contain internal repeats, and (viii do not contain PFAM domains, except those associated with pathogenicity. We used Markov clustering and hierarchical clustering to classify protein families of rust pathogens and rank them according to their likelihood of being effectors. Using this approach, we identified eight families of candidate effectors that we consider of high value for functional characterization. This study revealed a diverse set of candidate effectors, including families of haustorial expressed secreted proteins and small cysteine-rich proteins. This comprehensive classification of candidate effectors from these devastating rust pathogens is an initial step towards probing plant germplasm for novel resistance components.

  5. End-Effector Development for the PIP Puck Handling Robot

    International Nuclear Information System (INIS)

    Fowley, M.D.

    2001-01-01

    It has been decided that excess, weapons-grade plutonium shall be immobilized to prevent nuclear proliferation. The method of immobilization is to encapsulate the plutonium in a ceramic puck, roughly the size of a hockey puck, using a sintering process. This method has been officially identified as the Plutonium Immobilization Process (PIP). A Can-in-Canister storage method will be used to further immobilize the plutonium. The Can-in-Canister method uses the existing design of a Defense Waste Processing Facility (DWPF) canister to house the plutonium pucks. the process begins with several pucks being stacked in a stainless steel can. Several of the stainless steel cans are stacked in a cage-like magazine. Several of the magazines are then placed in a DWPF canister. The DWPF canister is then filled with molten glass containing high-level, radioactive waste from the DWPF vitrification process. The Can-in-Canister method makes reclamation of plutonium from the pucks technically difficult and highly undesirable. The mechanical requirements of the Can-in-Canister process, in conjunction with the amount of time required to immobilize the vast quantities of weapons-grade plutonium, will expose personnel to unnecessarily high levels of radiation if the processes were completed manually, in glove boxes. Therefore, automated equipment is designed into the process to reduce or eliminate personnel exposure. Robots are used whenever the automated handling operations become complicated. There are two such operations in the initial stages of the Can-in-Canister process, which required a six-axis robot. The first operation is a press unloading process. The second operation is a tray transfer process. To successfully accomplish the operational tasks described in the two operations, the end-effector of the robot must be versatile, lightweight, and rugged. As a result of these demands, an extensive development process was undertaken to design the optimum end-effector for these puck

  6. Identification and characterisation of a hyper-variable apoplastic effector gene family of the potato cyst nematodes.

    Directory of Open Access Journals (Sweden)

    Sebastian Eves-van den Akker

    2014-09-01

    Full Text Available Sedentary endoparasitic nematodes are obligate biotrophs that modify host root tissues, using a suite of effector proteins to create and maintain a feeding site that is their sole source of nutrition. Using assumptions about the characteristics of genes involved in plant-nematode biotrophic interactions to inform the identification strategy, we provide a description and characterisation of a novel group of hyper-variable extracellular effectors termed HYP, from the potato cyst nematode Globodera pallida. HYP effectors comprise a large gene family, with a modular structure, and have unparalleled diversity between individuals of the same population: no two nematodes tested had the same genetic complement of HYP effectors. Individuals vary in the number, size, and type of effector subfamilies. HYP effectors are expressed throughout the biotrophic stages in large secretory cells associated with the amphids of parasitic stage nematodes as confirmed by in situ hybridisation. The encoded proteins are secreted into the host roots where they are detectable by immunochemistry in the apoplasm, between the anterior end of the nematode and the feeding site. We have identified HYP effectors in three genera of plant parasitic nematodes capable of infecting a broad range of mono- and dicotyledon crop species. In planta RNAi targeted to all members of the effector family causes a reduction in successful parasitism.

  7. Molecular pathway profiling of T lymphocyte signal transduction pathways; Th1 and Th2 genomic fingerprints are defined by TCR and CD28-mediated signaling

    NARCIS (Netherlands)

    Smeets, Ruben L.; Fleuren, Wilco W. M.; He, Xuehui; Vink, Paul M.; Wijnands, Frank; Gorecka, Monika; Klop, Henri; Bauerschmidt, Sussane; Garritsen, Anja; Koenen, Hans J. P. M.; Joosten, Irma; Boots, Annemieke M. H.; Alkema, Wynand

    2012-01-01

    Background: T lymphocytes are orchestrators of adaptive immunity. Naive T cells may differentiate into Th1, Th2, Th17 or iTreg phenotypes, depending on environmental co-stimulatory signals. To identify genes and pathways involved in differentiation of Jurkat T cells towards Th1 and Th2 subtypes we

  8. Molecular pathway profiling of T lymphocyte signal transduction pathways; Th1 and Th2 genomic fingerprints are defined by TCR and CD28-mediated signaling.

    NARCIS (Netherlands)

    Smeets, R.L.; Fleuren, W.W.M.; He, X.; Vink, P.M.; Wijnands, F.; Gorecka, M.; Klop, H.; Bauerschmidt, S.; Garritsen, A.; Koenen, H.J.P.M.; Joosten, I.; Boots, A.M.H.; Alkema, W.

    2012-01-01

    BACKGROUND: T lymphocytes are orchestrators of adaptive immunity. Naive T cells may differentiate into Th1, Th2, Th17 or iTreg phenotypes, depending on environmental co-stimulatory signals. To identify genes and pathways involved in differentiation of Jurkat T cells towards Th1 and Th2 subtypes we

  9. Acquired transcriptional programming in functional and exhausted virus-specific CD8 T cells.

    Science.gov (United States)

    Youngblood, Ben; Wherry, E John; Ahmed, Rafi

    2012-01-01

    Failure to control viral infections such as HIV results in T-cell receptor (TCR) and inhibitory receptor driven exhaustion of antigen-specific T cells. Persistent signaling by these receptors during chronic viral infection sculpts the transcriptional regulatory programs of virus-specific T cells. The resulting gene expression profile is tailored to temper the potentially damaging effector functions of cytotoxic T cells and adapt them to an antigen-rich and inflammation-rich environment. Here we review recent studies investigating mechanisms of transcriptional regulation of effector, functional memory, and exhausted T-cell functions during acute versus chronic infections. Patterns of gene expression in virus-specific CD8 T cells are a result of a combination of pro and inhibitory signals from antigen presentation (TCR-mediated) and co-inhibitory receptor ligation (PD-1, 2B4). Further, memory-specific transcriptional regulation of 2B4 expression and signaling impose a self-limiting secondary effector response to a prolonged viral infection. Additionally, differentiation of functional memory CD8 T cells is coupled with acquisition of a repressive epigenetic program for PD-1 expression. However, chronic infection provides a signal that blocks the acquisition of these epigenetic modifications reinforcing the suppression of cytotoxic lymphocyte (CTL) functions in exhausted cells. Current findings suggest that the mechanism(s) that delineate functional memory versus exhaustion are coupled with acquisition of transcriptional programs at the effector stage of differentiation, reinforced by cessation or persistence of TCR signaling.

  10. Systems biology of neutrophil differentiation and immune response

    DEFF Research Database (Denmark)

    Theilgaard-Mönch, Kim; Porse, Bo T; Borregaard, Niels

    2005-01-01

    Systems biology has emerged as a new scientific field, which aims at investigating biological processes at the genomic and proteomic levels. Recent studies have unravelled aspects of neutrophil differentiation and immune responses at the systems level using high-throughput technologies. These stu......Systems biology has emerged as a new scientific field, which aims at investigating biological processes at the genomic and proteomic levels. Recent studies have unravelled aspects of neutrophil differentiation and immune responses at the systems level using high-throughput technologies....... These studies have identified a plethora of novel effector proteins stored in the granules of neutrophils. In addition, these studies provide evidence that neutrophil differentiation and immune response are governed by a highly coordinated transcriptional programme that regulates cellular fate and function...

  11. MYR1-Dependent Effectors Are the Major Drivers of a Host Cell's Early Response to Toxoplasma, Including Counteracting MYR1-Independent Effects.

    Science.gov (United States)

    Naor, Adit; Panas, Michael W; Marino, Nicole; Coffey, Michael J; Tonkin, Christopher J; Boothroyd, John C

    2018-04-03

    The obligate intracellular parasite Toxoplasma gondii controls its host cell from within the parasitophorous vacuole (PV) by using a number of diverse effector proteins, a subset of which require the aspartyl protease 5 enzyme (ASP5) and/or the recently discovered MYR1 protein to cross the PV membrane. To examine the impact these effectors have in the context of the entirety of the host response to Toxoplasma , we used RNA-Seq to analyze the transcriptome expression profiles of human foreskin fibroblasts infected with wild-type RH (RH-WT), RHΔ myr1 , and RHΔ asp5 tachyzoites. Interestingly, the majority of the differentially regulated genes responding to Toxoplasma infection are MYR1 dependent. A subset of MYR1 responses were ASP5 independent, and MYR1 function did not require ASP5 cleavage, suggesting the export of some effectors requires only MYR1. Gene set enrichment analysis of MYR1-dependent host responses suggests an upregulation of E2F transcription factors and the cell cycle and a downregulation related to interferon signaling, among numerous others. Most surprisingly, "hidden" responses arising in RHΔ myr1 - but not RH-WT-infected host cells indicate counterbalancing actions of MYR1-dependent and -independent activities. The host genes and gene sets revealed here to be MYR1 dependent provide new insight into the parasite's ability to co-opt host cell functions. IMPORTANCE Toxoplasma gondii is unique in its ability to successfully invade and replicate in a broad range of host species and cells within those hosts. The complex interplay of effector proteins exported by Toxoplasma is key to its success in co-opting the host cell to create a favorable replicative niche. Here we show that a majority of the transcriptomic effects in tachyzoite-infected cells depend on the activity of a novel translocation system involving MYR1 and that the effectors delivered by this system are part of an intricate interplay of activators and suppressors. Removal of all MYR1

  12. X-linked inhibitor of apoptosis regulates T cell effector function

    DEFF Research Database (Denmark)

    Zehntner, Simone P; Bourbonnière, Lyne; Moore, Craig S

    2007-01-01

    To understand how the balance between pro- and anti-apoptotic signals influences effector function in the immune system, we studied the X-linked inhibitor of apoptosis (XIAP), an endogenous regulator of cellular apoptosis. Real-time PCR showed increased XIAP expression in blood of mice with exper......To understand how the balance between pro- and anti-apoptotic signals influences effector function in the immune system, we studied the X-linked inhibitor of apoptosis (XIAP), an endogenous regulator of cellular apoptosis. Real-time PCR showed increased XIAP expression in blood of mice...... dramatically reduced within the CNS. Flow cytometry showed an 88-93% reduction in T cells. The proportion of TUNEL(+) apoptotic CD4(+) T cells in the CNS was increased from Neurons...... and oligodendrocytes were not affected; neither did apoptosis increase in liver, where XIAP knockdown also occurred. ASO-XIAP increased susceptibility of T cells to activation-induced apoptosis in vitro. Our results identify XIAP as a critical controller of apoptotic susceptibility of effector T cell function...

  13. Immunomodulatory Activity of Ganoderma atrum Polysaccharide on Purified T Lymphocytes through Ca2+/CaN and Mitogen-Activated Protein Kinase Pathway Based on RNA Sequencing.

    Science.gov (United States)

    Xiang, Quan-Dan; Yu, Qiang; Wang, Hui; Zhao, Ming-Ming; Liu, Shi-Yu; Nie, Shao-Ping; Xie, Ming-Yong

    2017-07-05

    Our previous study has demonstrated that Ganoderma atrum polysaccharide (PSG-1) has immunomodulatory activity on spleen lymphocytes. However, how PSG-1 exerts its effect on purified lymphocytes is still obscure. Thus, this study aimed to investigate the immunomodulatory activity of PSG-1 on purified T lymphocytes and further elucidate the underlying mechanism based on RNA sequencing (RNA-seq). Our results showed that PSG-1 promoted T lymphocytes proliferation and increased the production of IL-2, IFN-γ, and IL-12. Meanwhile, RNA-seq analysis found 394 differentially expressed genes. KEGG pathway analysis identified 20 significant canonical pathways and seven biological functions. Furthermore, PSG-1 elevated intracellular Ca 2+ concentration and calcineurin (CaN) activity and raised the p-ERK, p-JNK, and p-p38 expression levels. T lymphocytes proliferation and the production of IL-2, IFN-γ, and IL-12 were decreased by the inhibitors of calcium channel and mitogen-activated protein kinases (MAPKs). These results indicated that PSG-1 possesses immunomodulatory activity on purified T lymphocytes, in which Ca 2+ /CaN and MAPK pathways play essential roles.

  14. Effect of radiotherapy on lymphocyte cytotoxicity in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Wasserman, J; Melen, B [Central Microbiological Laboratory, Stockholm County Council (Sweden); Blomgren, H; Glas, U; Perlmann, P

    1975-11-01

    The cytotoxic functions of highly purified blood lymphocytes from patients with breast cancer were studied before and after radiotherapy. Addition of PHA or of rabbit antibodies to target cells (chicken erythrocytes) were chosen as two means of inducing lymphocyte cytotoxicity in vitro. The proportion of T and non-T lymphocytes was determined by means of E and EAC rosette tests. The antibody-induced cytotoxicity of lymphocytes decreased following radiotherapy while that mediated by PHA remained unchanged. There was some reduction in the percentage of EAC rosette-forming cells. These results, as well as earlier observations, suggest that the decrease in the peripheral blood of the proportion of lymphocytes with receptors for activated complement is responsible for changes in the antibody-mediated lymphocyte cytotoxicity.

  15. MALT1 Inhibition Is Efficacious in Both Naïve and Ibrutinib-Resistant Chronic Lymphocytic Leukemia.

    Science.gov (United States)

    Saba, Nakhle S; Wong, Deanna H; Tanios, Georges; Iyer, Jessica R; Lobelle-Rich, Patricia; Dadashian, Eman L; Liu, Delong; Fontan, Lorena; Flemington, Erik K; Nichols, Cydney M; Underbayev, Chingiz; Safah, Hana; Melnick, Ari; Wiestner, Adrian; Herman, Sarah E M

    2017-12-15

    The clinical efficacy displayed by ibrutinib in chronic lymphocytic leukemia (CLL) has been challenged by the frequent emergence of resistant clones. The ibrutinib target, Bruton's tyrosine kinase (BTK), is essential for B-cell receptor signaling, and most resistant cases carry mutations in BTK or PLCG2 , a downstream effector target of BTK. Recent findings show that MI-2, a small molecule inhibitor of the para-caspase MALT1, is effective in preclinical models of another type of BCR pathway-dependent lymphoma. We therefore studied the activity of MI-2 against CLL and ibrutinib-resistant CLL. Treatment of CLL cells in vitro with MI-2 inhibited MALT1 proteolytic activity reduced BCR and NF-κB signaling, inhibited nuclear translocation of RelB and p50, and decreased Bcl-xL levels. MI-2 selectively induced dose and time-dependent apoptosis in CLL cells, sparing normal B lymphocytes. Furthermore, MI-2 abrogated survival signals provided by stromal cells and BCR cross-linking and was effective against CLL cells harboring features associated with poor outcomes, including 17p deletion and unmutated IGHV Notably, MI-2 was effective against CLL cells collected from patients harboring mutations conferring resistance to ibrutinib. Overall, our findings provide a preclinical rationale for the clinical development of MALT1 inhibitors in CLL, in particular for ibrutinib-resistant forms of this disease. Cancer Res; 77(24); 7038-48. ©2017 AACR . ©2017 American Association for Cancer Research.

  16. Consequences of exposure to ionizing radiation for effector T cell function in vivo

    International Nuclear Information System (INIS)

    Rouse, B.T.; Hartley, D.; Doherty, P.C.

    1989-01-01

    The adoptive transfer of acutely primed and memory virus-immune CD8+ T cells causes enhanced meningitis in both cyclophosphamide (Cy) suppressed, and unsuppressed, recipients infected with lymphocytic choriomeningitis virus (LCMV). The severity of meningitis is assessed by counting cells in cerebrospinal fluid (CSF) obtained from the cisterna magna, which allows measurement of significant inflammatory process ranging from 3 to more than 300 times the background number of cells found in mice injected with virus alone. Exposure of the donor immune population to ionizing radiation prior to transfer has shown that activated T cells from mice primed 7 or 8 days previously with virus may still promote a low level of meningitis in unsuppressed recipients following as much as 800 rads, while this effect is lost totally in Cy-suppressed mice at 600 rads. Memory T cells are more susceptible and show no evidence of in vivo effector function in either recipient population subsequent to 400 rads, a dose level which also greatly reduces the efficacy of acutely-primed T cells. The results are interpreted as indicating that heavily irradiated cells that are already fully functional show evidence of primary localization to the CNS and a limited capacity to cause pathology. Secondary localization, and events that require further proliferation of the T cells in vivo, are greatly inhibited by irradiation

  17. Consequences of exposure to ionizing radiation for effector T cell function in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Rouse, B.T.; Hartley, D.; Doherty, P.C. (Univ. of Tennessee, Knoxville (USA))

    1989-01-01

    The adoptive transfer of acutely primed and memory virus-immune CD8+ T cells causes enhanced meningitis in both cyclophosphamide (Cy) suppressed, and unsuppressed, recipients infected with lymphocytic choriomeningitis virus (LCMV). The severity of meningitis is assessed by counting cells in cerebrospinal fluid (CSF) obtained from the cisterna magna, which allows measurement of significant inflammatory process ranging from 3 to more than 300 times the background number of cells found in mice injected with virus alone. Exposure of the donor immune population to ionizing radiation prior to transfer has shown that activated T cells from mice primed 7 or 8 days previously with virus may still promote a low level of meningitis in unsuppressed recipients following as much as 800 rads, while this effect is lost totally in Cy-suppressed mice at 600 rads. Memory T cells are more susceptible and show no evidence of in vivo effector function in either recipient population subsequent to 400 rads, a dose level which also greatly reduces the efficacy of acutely-primed T cells. The results are interpreted as indicating that heavily irradiated cells that are already fully functional show evidence of primary localization to the CNS and a limited capacity to cause pathology. Secondary localization, and events that require further proliferation of the T cells in vivo, are greatly inhibited by irradiation.

  18. A Plant Immune Receptor Detects Pathogen Effectors that Target WRKY Transcription Factors.

    Science.gov (United States)

    Sarris, Panagiotis F; Duxbury, Zane; Huh, Sung Un; Ma, Yan; Segonzac, Cécile; Sklenar, Jan; Derbyshire, Paul; Cevik, Volkan; Rallapalli, Ghanasyam; Saucet, Simon B; Wirthmueller, Lennart; Menke, Frank L H; Sohn, Kee Hoon; Jones, Jonathan D G

    2015-05-21

    Defense against pathogens in multicellular eukaryotes depends on intracellular immune receptors, yet surveillance by these receptors is poorly understood. Several plant nucleotide-binding, leucine-rich repeat (NB-LRR) immune receptors carry fusions with other protein domains. The Arabidopsis RRS1-R NB-LRR protein carries a C-terminal WRKY DNA binding domain and forms a receptor complex with RPS4, another NB-LRR protein. This complex detects the bacterial effectors AvrRps4 or PopP2 and then activates defense. Both bacterial proteins interact with the RRS1 WRKY domain, and PopP2 acetylates lysines to block DNA binding. PopP2 and AvrRps4 interact with other WRKY domain-containing proteins, suggesting these effectors interfere with WRKY transcription factor-dependent defense, and RPS4/RRS1 has integrated a "decoy" domain that enables detection of effectors that target WRKY proteins. We propose that NB-LRR receptor pairs, one member of which carries an additional protein domain, enable perception of pathogen effectors whose function is to target that domain. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. An Aphid Effector Targets Trafficking Protein VPS52 in a Host-Specific Manner to Promote Virulence.

    Science.gov (United States)

    Rodriguez, Patricia A; Escudero-Martinez, Carmen; Bos, Jorunn I B

    2017-03-01

    Plant- and animal-feeding insects secrete saliva inside their hosts, containing effectors, which may promote nutrient release and suppress immunity. Although for plant pathogenic microbes it is well established that effectors target host proteins to modulate host cell processes and promote disease, the host cell targets of herbivorous insects remain elusive. Here, we show that the existing plant pathogenic microbe effector paradigm can be extended to herbivorous insects in that effector-target interactions inside host cells modify critical host processes to promote plant susceptibility. We showed that the effector Mp1 from Myzus persicae associates with the host Vacuolar Protein Sorting Associated Protein52 (VPS52). Using natural variants, we provide a strong link between effector virulence activity and association with VPS52, and show that the association is highly specific to M persicae -host interactions. Also, coexpression of Mp1, but not Mp1-like variants, specifically with host VPS52s resulted in effector relocalization to vesicle-like structures that associate with prevacuolar compartments. We show that high VPS52 levels negatively impact virulence, and that aphids are able to reduce VPS52 levels during infestation, indicating that VPS52 is an important virulence target. Our work is an important step forward in understanding, at the molecular level, how a major agricultural pest promotes susceptibility during infestation of crop plants. We give evidence that an herbivorous insect employs effectors that interact with host proteins as part of an effective virulence strategy, and that these effectors likely function in a species-specific manner. © 2017 American Society of Plant Biologists. All Rights Reserved.

  20. Metal ion levels and lymphocyte counts

    DEFF Research Database (Denmark)

    Penny, Jeannette Ø; Varmarken, Jens-Erik; Ovesen, Ole

    2013-01-01

    BACKGROUND AND PURPOSE: Wear particles from metal-on-metal arthroplasties are under suspicion for adverse effects both locally and systemically, and the DePuy ASR Hip Resurfacing System (RHA) has above-average failure rates. We compared lymphocyte counts in RHA and total hip arthroplasty (THA) an....../ppb. INTERPRETATION: Circulating T-lymphocyte levels may decline after surgery, regardless of implant type. Metal ions-particularly cobalt-may have a general depressive effect on T- and B-lymphocyte levels. Registered with ClinicalTrials.gov under # NCT01113762.......BACKGROUND AND PURPOSE: Wear particles from metal-on-metal arthroplasties are under suspicion for adverse effects both locally and systemically, and the DePuy ASR Hip Resurfacing System (RHA) has above-average failure rates. We compared lymphocyte counts in RHA and total hip arthroplasty (THA....... RESULTS: The T-lymphocyte counts for both implant types declined over the 2-year period. This decline was statistically significant for CD3(+)CD8(+) in the THA group, with a regression coefficient of -0.04 × 10(9)cells/year (95% CI: -0.08 to -0.01). Regression analysis indicated a depressive effect...

  1. Chronic lymphocytic leukemia/small lymphocytic lymphoma presenting as septic arthritis of the shoulder

    Energy Technology Data Exchange (ETDEWEB)

    Donovan, Andrea; Schweitzer, Mark E.; Nomikos, George [NYU Hospital for Joint Diseases, New York, NY (United States); Garcia, Roberto A. [Bellevue Hospital Center, New York, NY (United States)

    2008-11-15

    We report a case of a 53-year-old man presenting with shoulder pain mimicking septic arthritis. Laboratory findings were atypical. Biopsy performed to assess for possible osteomyelitis demonstrated chronic lymphocytic leukemia/small lymphocytic lymphoma. Intra-articular lymphoma is a rare but important consideration in patients with atypical clinical presentation. Imaging alone may be insufficient to render diagnosis as lymphoma can mimic infection, synovial hypertrophic processes, and depositional arthropathy. (orig.)

  2. Human memory CD8 T cell effector potential is epigenetically preserved during in vivo homeostasis.

    Science.gov (United States)

    Abdelsamed, Hossam A; Moustaki, Ardiana; Fan, Yiping; Dogra, Pranay; Ghoneim, Hazem E; Zebley, Caitlin C; Triplett, Brandon M; Sekaly, Rafick-Pierre; Youngblood, Ben

    2017-06-05

    Antigen-independent homeostasis of memory CD8 T cells is vital for sustaining long-lived T cell-mediated immunity. In this study, we report that maintenance of human memory CD8 T cell effector potential during in vitro and in vivo homeostatic proliferation is coupled to preservation of acquired DNA methylation programs. Whole-genome bisulfite sequencing of primary human naive, short-lived effector memory (T EM ), and longer-lived central memory (T CM ) and stem cell memory (T SCM ) CD8 T cells identified effector molecules with demethylated promoters and poised for expression. Effector-loci demethylation was heritably preserved during IL-7- and IL-15-mediated in vitro cell proliferation. Conversely, cytokine-driven proliferation of T CM and T SCM memory cells resulted in phenotypic conversion into T EM cells and was coupled to increased methylation of the CCR7 and Tcf7 loci. Furthermore, haploidentical donor memory CD8 T cells undergoing in vivo proliferation in lymphodepleted recipients also maintained their effector-associated demethylated status but acquired T EM -associated programs. These data demonstrate that effector-associated epigenetic programs are preserved during cytokine-driven subset interconversion of human memory CD8 T cells. © 2017 Abdelsamed et al.

  3. Ontogeny of B lymphocyte function. IV. Kinetics of maturation of B lymphocytes from fetal and neonatal mice when transferred into adult irradiated hosts

    International Nuclear Information System (INIS)

    Sherr, D.; Szewczuk, M.R.; Siskind, G.W.

    1977-01-01

    Lethally irradiated mice reconstituted with adult T cells and neonatal or fetal B cells produce an anti-DNP response of restricted heterogeneity of affinity when compared with the response of mice reconstituted with T and B cells from adult donors. The capacity to reconstitute adult mice to give a heterogeneous response matures between 7 and 10 days after birth. The maturation of B cells from day-15 fetal or neonatal donors to produce a heterogeneous response was followed in the adult, cell transfer recipient by immunizing them at different times after cell transfer. It was found that B cells both from day-15 fetal mice and from neonatal mice acquire the capacity to produce a heterogeneous response within 3 days in the adult, cell transfer recipient. Thus, the B cell population matures more rapidly in the cell transfer recipient than in the intact donor. The kinetics of maturation in the adult recipient is the same for B cells from day-15 fetal and neonatal donors. The data imply that all information required to produce a fully heterogeneous response is already present in the day-15 fetus. In addition, the data strongly support the hypothesis that a factor in the adult mouse acts to induce this step in the maturation of the B lymphocyte population. Thus, the data seem to be inconsistent with the view that the timing of the occurrence of this differentiation event is precoded in an internal cell clock in the B lymphocyte line. Clearly, B cells from day-15 fetal mice are already capable of differentiating in response to the inducing factor which is present in the adult animal

  4. Identification, structure, and function of a novel type VI secretion peptidoglycan glycoside hydrolase effector-immunity pair.

    Science.gov (United States)

    Whitney, John C; Chou, Seemay; Russell, Alistair B; Biboy, Jacob; Gardiner, Taylor E; Ferrin, Michael A; Brittnacher, Mitchell; Vollmer, Waldemar; Mougous, Joseph D

    2013-09-13

    Bacteria employ type VI secretion systems (T6SSs) to facilitate interactions with prokaryotic and eukaryotic cells. Despite the widespread identification of T6SSs among Gram-negative bacteria, the number of experimentally validated substrate effector proteins mediating these interactions remains small. Here, employing an informatics approach, we define novel families of T6S peptidoglycan glycoside hydrolase effectors. Consistent with the known intercellular self-intoxication exhibited by the T6S pathway, we observe that each effector gene is located adjacent to a hypothetical open reading frame encoding a putative periplasmically localized immunity determinant. To validate our sequence-based approach, we functionally investigate a representative family member from the soil-dwelling bacterium Pseudomonas protegens. We demonstrate that this protein is secreted in a T6SS-dependent manner and that it confers a fitness advantage in growth competition assays with Pseudomonas putida. In addition, we determined the 1.4 Å x-ray crystal structure of this effector in complex with its cognate immunity protein. The structure reveals the effector shares highest overall structural similarity to a glycoside hydrolase family associated with peptidoglycan N-acetylglucosaminidase activity, suggesting that T6S peptidoglycan glycoside hydrolase effector families may comprise significant enzymatic diversity. Our structural analyses also demonstrate that self-intoxication is prevented by the immunity protein through direct occlusion of the effector active site. This work significantly expands our current understanding of T6S effector diversity.

  5. Identification, Structure, and Function of a Novel Type VI Secretion Peptidoglycan Glycoside Hydrolase Effector-Immunity Pair*

    Science.gov (United States)

    Whitney, John C.; Chou, Seemay; Russell, Alistair B.; Biboy, Jacob; Gardiner, Taylor E.; Ferrin, Michael A.; Brittnacher, Mitchell; Vollmer, Waldemar; Mougous, Joseph D.

    2013-01-01

    Bacteria employ type VI secretion systems (T6SSs) to facilitate interactions with prokaryotic and eukaryotic cells. Despite the widespread identification of T6SSs among Gram-negative bacteria, the number of experimentally validated substrate effector proteins mediating these interactions remains small. Here, employing an informatics approach, we define novel families of T6S peptidoglycan glycoside hydrolase effectors. Consistent with the known intercellular self-intoxication exhibited by the T6S pathway, we observe that each effector gene is located adjacent to a hypothetical open reading frame encoding a putative periplasmically localized immunity determinant. To validate our sequence-based approach, we functionally investigate a representative family member from the soil-dwelling bacterium Pseudomonas protegens. We demonstrate that this protein is secreted in a T6SS-dependent manner and that it confers a fitness advantage in growth competition assays with Pseudomonas putida. In addition, we determined the 1.4 Å x-ray crystal structure of this effector in complex with its cognate immunity protein. The structure reveals the effector shares highest overall structural similarity to a glycoside hydrolase family associated with peptidoglycan N-acetylglucosaminidase activity, suggesting that T6S peptidoglycan glycoside hydrolase effector families may comprise significant enzymatic diversity. Our structural analyses also demonstrate that self-intoxication is prevented by the immunity protein through direct occlusion of the effector active site. This work significantly expands our current understanding of T6S effector diversity. PMID:23878199

  6. Inhibition of human peripheral blood lymphocyte function by protoporphyrin and longwave ultraviolet light

    International Nuclear Information System (INIS)

    Barrett, K.E.; Yen, A.; Montisano, D.; Gigli, I.; Bigby, T.D.

    1994-01-01

    Modulation of immunologic effector cells by exogenous photoactive substances has been advanced as an underlying mechanism for the efficacy of various photochemotherapeutic regimens. It is also possible that endogenous photosensitizers, such as protoporphyrin, could similarly modify the function of immune cell types. The authors examined the effects of protoporphyrin plus longwave UV light on the ability of human PBL to proliferate in response to mitogens. Noncytotoxic dosages of protoporphyrin plus UV light suppressed PHA-stimulated proliferation of both PBMC and enriched T cells. CD8 + cells were more sensitive to this inhibitory effect than CD4 + cells. The inhibitory effect was also observed when proliferation was induced by the combination of a phorbol ester and ionomycin. Inhibition of PBMC proliferation was associated with inhibition of IL-2 secretion but proliferation was not restored with exogenous IL-2. Instead, the effect of protoporphyrin plus UV light may be on IL-2R. Cells treated with protoporphyrin and UV light did not display the increase in CD25 and β-chain of the IL-2R induced by PHA in control cells. In contrast to the effects of protoporphyrin and UV light on IL-2 and IL-2R α-chain protein expression, the accumulation of mRNA for these proteins induced by PHA was unaffected. None of the effects of protoporphyrin plus UV light on lymphocytes were observed in control experiments where cells were treated with either protoporphyrin or UV light alone. They conclude that biologically relevant dosages of protoporphyrin and UV light modify the function of circulating lymphocytes. 26 refs., 8 figs., 1 tab

  7. B-lymphocyte differentiation in lethally irradiated and reconstituted mice. II. Recovery of humoral immune responsiveness

    International Nuclear Information System (INIS)

    Rozing, J.; Brons, N.H.C.; Benner, R.

    1977-01-01

    The recovery of humoral immune responsiveness was studied in lethally irradiated, fetal liver-reconstituted mice. By means of both membrane fluorescence and antibody formation to sheep red blood cells (SRBC) as a functional assay, the rate of recovery of the compartments of B and T lymphocytes was determined in various lymphoid organs. The recovery of the immunoglobulin-positive (B) cell compartment after irradiation and reconstitution started in the spleen. This organ was also found to be the first in which the recovery of the B-cell population was completed. The interval between the recovery of the B-cell population in the spleen and that in the other organs tested was found to increase when the irradiated mice were reconstituted with spleen colony cells instead of fetal liver cells. This proved to be caused by the number and nature of the reconstituting hemopoietic stem cells. The immunoglobulin-positive (B) cells were found to appear before SRBC-reactive B cells could be demonstrated in spleen, lymph nodes, and Peyer's patches. The appearance of T lymphocytes in the various lymphoid organs required even more time. By means of cell transfer experiments, a sequential appearance of the precursors of anti-SRBC IgM-, IgG-, and IgA-plaque-forming cells could be demonstrated in spleen, bone marrow, lymph nodes, and Peyer's patches

  8. Group I Paks Promote Skeletal Myoblast Differentiation In Vivo and In Vitro

    DEFF Research Database (Denmark)

    Joseph, Giselle A; Lu, Min; Radu, Maria

    2017-01-01

    fusion in Drosophila We report that both Pak1 and Pak2 are activated during mammalian myoblast differentiation. One pathway of activation is initiated by N-cadherin ligation and involves the cadherin coreceptor Cdo with its downstream effector, Cdc42. Individual genetic deletion of Pak1 and Pak2 in mice....... Furthermore, primary myoblasts lacking Pak1 and Pak2 display delayed expression of myogenic differentiation markers and myotube formation. These results identify Pak1 and Pak2 as redundant regulators of myoblast differentiation in vitro and in vivo and as components of the promyogenic Ncad/Cdo/Cdc42 signaling...

  9. A microculture technique for rat lymphocyte transformation.

    Science.gov (United States)

    Lindsay, V J; Allardyce, R A

    1979-01-01

    We report the development of an economical microculture technique suitable for measuring rat lymphocyte response to mitogens and in mixed lymphocyte reactions. The effects of varying culture conditions, i.e. source of serum, addition and concentration of 2-mercaptoethanol, mitogen concentrations, culture incubation times, absorption of serum, lymphocyte numbers and microtitre plate well shape are described.

  10. Damage of lymphocytes by ionizing irradiation

    International Nuclear Information System (INIS)

    Rose, H.; Moldenhauer, H.; Kehrberg, G.

    1985-01-01

    After a short review, how lymphocytes of the peripheral blood are influenced by radiotherapy, the damage of lymphocytes by whole-body irradiation is pointed out in animal experiments and after in vitro irradiation. The special sensibility of B-cells and their homogeneity in fields of radiobiology are opposed to the heterogeneity of T-cells. The radiosensibility of cytotoxic lymphocytes, suppressor cells, and helper cells are discussed. It appears, that within these functional criteria, there is a different radiosensibility, too. (author)

  11. Intrinsic disorder in pathogen effectors: protein flexibility as an evolutionary hallmark in a molecular arms race.

    Science.gov (United States)

    Marín, Macarena; Uversky, Vladimir N; Ott, Thomas

    2013-09-01

    Effector proteins represent a refined mechanism of bacterial pathogens to overcome plants' innate immune systems. These modular proteins often manipulate host physiology by directly interfering with immune signaling of plant cells. Even if host cells have developed efficient strategies to perceive the presence of pathogenic microbes and to recognize intracellular effector activity, it remains an open question why only few effectors are recognized directly by plant resistance proteins. Based on in-silico genome-wide surveys and a reevaluation of published structural data, we estimated that bacterial effectors of phytopathogens are highly enriched in long-disordered regions (>50 residues). These structurally flexible segments have no secondary structure under physiological conditions but can fold in a stimulus-dependent manner (e.g., during protein-protein interactions). The high abundance of intrinsic disorder in effectors strongly suggests positive evolutionary selection of this structural feature and highlights the dynamic nature of these proteins. We postulate that such structural flexibility may be essential for (1) effector translocation, (2) evasion of the innate immune system, and (3) host function mimicry. The study of these dynamical regions will greatly complement current structural approaches to understand the molecular mechanisms of these proteins and may help in the prediction of new effectors.

  12. Autoimmune hepatitis in association with lymphocytic colitis.

    LENUS (Irish Health Repository)

    Cronin, Edmond M

    2012-02-03

    Autoimmune hepatitis is a rare, chronic inflammatory disorder which has been associated with a number of other auto-immune conditions. However, there are no reports in the medical literature of an association with microscopic (lymphocytic) colitis. We report the case of a 53-year-old woman with several autoimmune conditions, including lymphocytic colitis, who presented with an acute hepatitis. On the basis of the clinical features, serology, and histopathology, we diagnosed autoimmune hepatitis. To our knowledge, this is the first report of autoimmune hepatitis in association with lymphocytic colitis, and lends support to the theory of an autoimmune etiology for lymphocytic colitis.

  13. Perfusion and spectroscopy magnetic resonance imaging in a case of lymphocytic vasculitis mimicking brain tumor

    International Nuclear Information System (INIS)

    Muccio, Carmine Franco; Di Blasi, Arturo; Esposito, Gennaro; Brunese, Luca; D’Arco, Felice; Caranci, Ferdinando

    2013-01-01

    Lymphocytic vasculitis of the central nervous system is an uncommon subtype of primary angiitis of the central nervous system (PACNS) – a rare inflammatory disorder affecting parenchymal and leptomeningeal arteries and veins. Establishing diagnosis on the basis of neuroimaging only is difficult, as it can mimic a brain tumor. Thus, histological diagnosis is essential for appropriate management. We present a case of biopsy-proven lymphocytic vasculitis mimicking a brain tumor on neuroimaging that was subsequently successfully treated with steroid therapy. We also discuss the findings in perfusion MR (PWI) and MR spectroscopy (MRS). Regional hypoperfusion on PWI and elevation of glutamate and glutamine levels on MRS (without associated typical tumor spectra) are common findings in inflammatory disorders, including PACNS, and can be useful in differential diagnosis with tumors

  14. Exact positioning of the robotic arm end effector

    Science.gov (United States)

    Korepanov, Valery; Dudkin, Fedir

    2016-07-01

    Orbital service becomes a new challenge of space exploration. The necessity to introduce it is connected first of all with an attractive opportunity to prolong the exploitation terms of expensive commercial satellites by, e.g., refilling of fuel or changing batteries. Other application area is a fight with permanently increasing amount of space litter - defunct satellites, burnt-out rocket stages, discarded trash and other debris. Now more than few tens of thousands orbiting objects larger than 5-10 cm (or about 1 million junks larger than 1 cm) are a huge problem for crucial and costly satellites and manned vehicles. For example, in 2014 the International Space Station had to change three times its orbit to avoid collision with space debris. So the development of the concepts and actions related to removal of space debris or non-operational satellites with use of robotic arm of a servicing satellite is very actual. Such a technology is also applicable for unmanned exploratory missions in solar system, for example for collecting a variety of samples from a celestial body surface. Naturally, the robotic arm movements should be controlled with great accuracy at influence of its non-rigidity, thermal and other factors. In these circumstances often the position of the arm end effector has to be controlled with high accuracy. The possibility of coordinate determination for the robotic arm end effector with use of a low frequency active electromagnetic system has been considered in the presented report. The proposed design of such a system consists of a small magnetic dipole source, which is mounted inside of the arm end effector and two or three 3-component magnetic field sensors mounted on a servicing satellite body. The data from this set of 3-component magnetic field sensors, which are fixed relatively to the satellite body, allows use of the mathematical approach for determination of position and orientation of the magnetic dipole source. The theoretical

  15. Mitochondrial DNA copy number and chronic lymphocytic leukemia/small lymphocytic lymphoma risk in two prospective studies

    NARCIS (Netherlands)

    Kim, Christopher; Bassig, Bryan A; Seow, Wei Jie; Hu, Wei; Purdue, Mark P; Huang, Wen-Yi; Liu, Chin-San; Cheng, Wen-Ling; Männistö, Satu; Vermeulen, Roel; Weinstein, Stephanie J; Lim, Unhee; Hosgood, H Dean; Bonner, Matthew R; Caporaso, Neil E; Albanes, Demetrius; Lan, Qing; Rothman, Nathaniel

    BACKGROUND: Mitochondrial DNA copy number (mtDNA CN) may be modified by mitochondria in response to oxidative stress. Previously, mtDNA CN was associated with non-Hodgkin lymphoma (NHL) risk, particularly chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). We conducted a replication

  16. Chloroplastic protein NRIP1 mediates innate immune receptor recognition of a viral effector

    Science.gov (United States)

    Caplan, Jeffrey L.; Mamillapalli, Padmavathi; Burch-Smith, Tessa M.; Czymmek, Kirk; Dinesh-Kumar, S.P.

    2008-01-01

    Summary Plant innate immunity relies on the recognition of pathogen effector molecules by nucleotide-binding-leucine-rich repeat (NB-LRR) immune receptor families. Previously we have shown the N immune receptor, a member of TIR-NB-LRR family, indirectly recognizes the 50-kDa helicase (p50) domain of Tobacco mosaic virus (TMV) through its TIR domain. We have identified an N receptor-interacting protein, NRIP1, that directly interacts with both N's TIR domain and p50. NRIP1 is a functional rhodanese sulfurtransferase and is required for N to provide complete resistance to TMV. Interestingly, NRIP1 that normally localizes to the chloroplasts is recruited to the cytoplasm and nucleus by the p50 effector. As a consequence, NRIP1 interacts with N only in the presence of the p50 effector. Our findings show that a chloroplastic protein is intimately involved in pathogen recognition. We propose that N's activation requires a pre-recognition complex containing the p50 effector and NRIP1. PMID:18267075

  17. Hematopoietic Stem and Progenitor Cells as Effectors in Innate Immunity

    Directory of Open Access Journals (Sweden)

    Jennifer L. Granick

    2012-01-01

    Full Text Available Recent research has shed light on novel functions of hematopoietic stem and progenitor cells (HSPC. While they are critical for maintenance and replenishment of blood cells in the bone marrow, these cells are not limited to the bone marrow compartment and function beyond their role in hematopoiesis. HSPC can leave bone marrow and circulate in peripheral blood and lymph, a process often manipulated therapeutically for the purpose of transplantation. Additionally, these cells preferentially home to extramedullary sites of inflammation where they can differentiate to more mature effector cells. HSPC are susceptible to various pathogens, though they may participate in the innate immune response without being directly infected. They express pattern recognition receptors for detection of endogenous and exogenous danger-associated molecular patterns and respond not only by the formation of daughter cells but can themselves secrete powerful cytokines. This paper summarizes the functional and phenotypic characterization of HSPC, their niche within and outside of the bone marrow, and what is known regarding their role in the innate immune response.

  18. [The lymphocyte transformation test in dermatology].

    Science.gov (United States)

    Zinn, K; Braun-Falco, O

    1976-03-01

    At first, immunologie and methodic basies of the lymphocyte transformation test are discussed. Then the results gained by this test in several dermatologic diseases are summarized. Finally, practice of the lymphocyte transformation test is critically reviewed.

  19. IMPACT OF HIV INFECTION AND TUBERCULOSIS ON THE PERIPHERAL BLOOD T-CELL DIFFERENTIATION

    Directory of Open Access Journals (Sweden)

    E. V. Vasileva

    2017-01-01

    Full Text Available Tuberculosis is the leading cause of death among HIV infected individuals. In this regard, an important task is the timely detection of tuberculosis in HIV infected patients. Previously, we have shown that the diagnostic value of in vitro test, QuantiFERON-TB Gold In-Tube is not decreased in patients with HIV infection against the background of tuberculosis. However, it remains unclear what kind of cell populations produce IFNγ in response to specific Mycobacterium tuberculosis antigens stimulation in vitro, because the immunodeficiency, caused by HIV, makes primarily for a decrease the abundance and attenuation functions of CD4 T-lymphocytes. The aim of thшы work was to compare the degree of differentiation of T-lymphocytes CD4 (Th and CD8 (Tcyt in patients with pulmonary tuberculosis and healthy donors against the background of HIV infection. The study data were obtained during the examination of 28 patients with pulmonary tuberculosis without HIV infection (HIV–TB+, 23 patients with HIV infection (TB–HIV+ and 30 patients coinfected with HIV and tuberculosis (TB+HIV+. The comparison group consisted of 37 healthy individuals (TB–HIV–. Аbsolute and abundance (relative content of major subpopulations of T-lymphocytes (based on the expression of CD27 marker, CD28, CD45RA and CD62L in the peripheral blood for all patients included in the study (n = 118 were evaluated by flow cytometry approach. For patients with pulmonary tuberculosis (n = 58 QuantiFERON-TB Gold In Tube (Qiagen, QFT test was performed. Th/Tcyt ratio was not significantly different among the groups of TB–HIV– and TB+HIV– (1.76 [1.51; 2.30] against 1.86 [1.22; 2.79], p = 0.960. At that time, the size of both subpopulations “terminally differentiated” Tcyt (Tcyt Eff, CD27–CD28– CD62L–CD45RA– Th lymphocytes and effector memory lymphocytes (Th EM, CD27–CD28+CD62L–CD45RA–, was significantly different in all four study groups. Multidirectional changes

  20. Antibody-Mediated Targeting of Tau In Vivo Does Not Require Effector Function and Microglial Engagement

    Directory of Open Access Journals (Sweden)

    Seung-Hye Lee

    2016-08-01

    Full Text Available The spread of tau pathology correlates with cognitive decline in Alzheimer’s disease. In vitro, tau antibodies can block cell-to-cell tau spreading. Although mechanisms of anti-tau function in vivo are unknown, effector function might promote microglia-mediated clearance. In this study, we investigated whether antibody effector function is required for targeting tau. We compared efficacy in vivo and in vitro of two versions of the same tau antibody, with and without effector function, measuring tau pathology, neuron health, and microglial function. Both antibodies reduced accumulation of tau pathology in Tau-P301L transgenic mice and protected cultured neurons against extracellular tau-induced toxicity. Only the full-effector antibody enhanced tau uptake in cultured microglia, which promoted release of proinflammatory cytokines. In neuron-microglia co-cultures, only effectorless anti-tau protected neurons, suggesting full-effector tau antibodies can induce indirect toxicity via microglia. We conclude that effector function is not required for efficacy, and effectorless tau antibodies may represent a safer approach to targeting tau.

  1. Radiosensitivity of lymphocytes among Filipinos: final report

    International Nuclear Information System (INIS)

    Medina, F.I.S.; Gregorio, J.S.; Aguilar, C.P.; Poblete, E.E.

    1996-01-01

    This report is about the studies on the radiosensitivity of Filipino lymphocytes to radiation that can elucidate on the potential of blood chromosomes as biological dosimeters. The objective of this study is to determine the radiosensitivity of lymphocytes among Filipinos and to establish the radiation-induced chromosome anomaly standard curve in lymphocytes for radiological dosimetry. 47 refs., 9 figs., 1 tab

  2. Differential gene expression by integrin β7+ and β7- memory T helper cells

    Directory of Open Access Journals (Sweden)

    Yang Yee

    2004-07-01

    Full Text Available Abstract Background The cell adhesion molecule integrin α4β7 helps direct the migration of blood lymphocytes to the intestine and associated lymphoid tissues. We hypothesized that β7+ and β7- blood memory T helper cells differ in their expression of genes that play a role in the adhesion or migration of T cells. Results RNA was prepared from β7+ and β7- CD4+ CD45RA- blood T cells from nine normal human subjects and analyzed using oligonucleotide microarrays. Of 21357 genes represented on the arrays, 16 were more highly expressed in β7+ cells and 18 were more highly expressed in β7- cells (≥1.5 fold difference and adjusted P + memory/effector T cells than on β7- cells. Conclusions Memory/effector T cells that express integrin β7 have a distinct pattern of expression of a set of gene transcripts. Several of these molecules can affect cell adhesion or chemotaxis and are therefore likely to modulate the complex multistep process that regulates trafficking of CD4+ memory T cell subsets with different homing behaviors.

  3. Combination of two anti-CD5 monoclonal antibodies synergistically induces complement-dependent cytotoxicity of chronic lymphocytic leukaemia cells.

    Science.gov (United States)

    Klitgaard, Josephine L; Koefoed, Klaus; Geisler, Christian; Gadeberg, Ole V; Frank, David A; Petersen, Jørgen; Jurlander, Jesper; Pedersen, Mikkel W

    2013-10-01

    The treatment of chronic lymphocytic leukaemia (CLL) has been improved by introduction of monoclonal antibodies (mAbs) that exert their effect through secondary effector mechanisms. CLL cells are characterized by expression of CD5 and CD23 along with CD19 and CD20, hence anti-CD5 Abs that engage secondary effector functions represent an attractive opportunity for CLL treatment. Here, a repertoire of mAbs against human CD5 was generated and tested for ability to induce complement-dependent cytotoxicity (CDC) and antibody-dependent cell-mediated cytotoxicity (ADCC) both as single mAbs and combinations of two mAbs against non-overlapping epitopes on human CD5. The results demonstrated that combinations of two mAbs significantly increased the level of CDC compared to the single mAbs, while no enhancement of ADCC was seen with anti-CD5 mAb combinations. High levels of CDC and ADCC correlated with low levels of Ab-induced CD5 internalization and degradation. Importantly, an anti-CD5 mAb combination enhanced CDC of CLL cells when combined with the anti-CD20 mAbs rituximab and ofatumumab as well as with the anti-CD52 mAb alemtuzumab. These results suggest that an anti-CD5 mAb combination inducing CDC and ADCC may be effective alone, in combination with mAbs against other targets or combined with chemotherapy for CLL and other CD5-expressing haematological or lymphoid malignancies. © 2013 John Wiley & Sons Ltd.

  4. Allograft immunity in vitro. I. Cultivation conditions and mixed lymphocyte interaction of mouse peripheral lymphocytes

    Science.gov (United States)

    Häyry, P.; Defendi, V.

    1970-01-01

    We have adapted mouse peripheral lymphocytes to culture as a preliminary step in designing a model for the study of allograft immunity in vitro. The isolation of peripheral leucocytes is facilitated by using Plasmagel® as an erythrocyte-agglutinating agent. The yield of leucocytes can be considerably increased by intravenous injection of the donor animals with supernatant fluid from Bordetella pertussis cultures and the lymphocytes thus mobilized react both to phytohaemagglutinin (PHA) and allogeneic stimulus, as do lymphocytes from untreated animals. Preparations which contain more than 25–50 RBC/WBC are refractory in the mixed lymphocyte interaction (MLI). The optimum cell density for the proliferative response is approximately 1–3 × 106 lymphocytes/ml. Various nutritive milieu were tested and found to have little influence on the MLI; both normal and suspension media behaved in a similar manner. PHA causes a vigorous proliferative response in mouse peripheral lymphocytes, the 3H–TdR incorporation values in PHA-containing cultures at peak point of stimulation (3rd day) being up to 1000 times those observed for control cultures. The allogeneic response in the MLI takes place later (6th to 7th day) and is weaker, about one-tenth the PHA response, when strains differing at the H-2 locus are used as cell donors. Because the specific proliferative response to allogeneic stimulus in mixed culture, regardless of the way it is measured, is indistinguishable from the response produced by other non-specific factors, these other factors must be critically excluded. It appears that supplementing the culture medium with low concentrations of certain lots of foetal calf or agamma-newborn-calf serum permits the study of the specific response at an optimum sensitivity. PMID:4315207

  5. Epigenetic control of CD8+ T cell differentiation.

    Science.gov (United States)

    Henning, Amanda N; Roychoudhuri, Rahul; Restifo, Nicholas P

    2018-05-01

    Upon stimulation, small numbers of naive CD8 + T cells proliferate and differentiate into a variety of memory and effector cell types. CD8 + T cells can persist for years and kill tumour cells and virally infected cells. The functional and phenotypic changes that occur during CD8 + T cell differentiation are well characterized, but the epigenetic states that underlie these changes are incompletely understood. Here, we review the epigenetic processes that direct CD8 + T cell differentiation and function. We focus on epigenetic modification of DNA and associated histones at genes and their regulatory elements. We also describe structural changes in chromatin organization that affect gene expression. Finally, we examine the translational potential of epigenetic interventions to improve CD8 + T cell function in individuals with chronic infections and cancer.

  6. Effector gene birth in plant parasitic nematodes: Neofunctionalization of a housekeeping glutathione synthetase gene

    Science.gov (United States)

    Lilley, Catherine J.; Maqbool, Abbas; Wu, Duqing; Yusup, Hazijah B.; Jones, Laura M.; Birch, Paul R. J.; Urwin, Peter E.

    2018-01-01

    Plant pathogens and parasites are a major threat to global food security. Plant parasitism has arisen four times independently within the phylum Nematoda, resulting in at least one parasite of every major food crop in the world. Some species within the most economically important order (Tylenchida) secrete proteins termed effectors into their host during infection to re-programme host development and immunity. The precise detail of how nematodes evolve new effectors is not clear. Here we reconstruct the evolutionary history of a novel effector gene family. We show that during the evolution of plant parasitism in the Tylenchida, the housekeeping glutathione synthetase (GS) gene was extensively replicated. New GS paralogues acquired multiple dorsal gland promoter elements, altered spatial expression to the secretory dorsal gland, altered temporal expression to primarily parasitic stages, and gained a signal peptide for secretion. The gene products are delivered into the host plant cell during infection, giving rise to “GS-like effectors”. Remarkably, by solving the structure of GS-like effectors we show that during this process they have also diversified in biochemical activity, and likely represent the founding members of a novel class of GS-like enzyme. Our results demonstrate the re-purposing of an endogenous housekeeping gene to form a family of effectors with modified functions. We anticipate that our discovery will be a blueprint to understand the evolution of other plant-parasitic nematode effectors, and the foundation to uncover a novel enzymatic function. PMID:29641602

  7. A comparative immunohistochemical and immunophenotypical study on lymphocytes expression in patients affected by oral lichen planus.

    Science.gov (United States)

    Lorenzini, Guido; Viviano, Massimo; Chisci, Elettra; Chisci, Glauco; Picciotti, Maria

    2013-09-01

    Oral lichen planus (OLP) is an immune-mediated mucocutaneous disease of uncertain aetiology. OLP has many manifestations: reticular, erosive, atrophic, plaque like, papular, bullous, with unique etiopathogenetic working. The purpose of this study is to find a link between different clinical types of lichen and the alterations of lymphocytes on peripheral blood and oral mucosa. A total of 21 patients were enrolled in this study. The mean age of patients was 53.82 years, between 31 and 78 years. OLP Diagnosis was afterwards confirmed by histopathology. Selected patients underwent to clinical evaluation, lesion characterization, incisional biopsy, samples histological analysis, peripheral blood collection. Blood specimens were submitted to cell count determination with differential, characterization of populations and circulating lymphocyte subpopulations using monoclonal antibodies in flow cytometry. Referring to the clinical presentation of lesions, patients were divided in two groups: red lesions (RL) and white lesions (WL) and compared with an age-matched control group. The results of the immunophenotypic study showed correlation between WL and the expression of CD19 lymphocytes (r = 0.693, P = 0.0005). The results of immunohistochemical study performed on histological specimens showed a significant correlation between RL group and expression of all lymphocyte tested (CD3 r = 0.722 P = 0.0002, CD4 r = 0.579 P = 0.0060, CD56 r = 0.513 P = 0.0173, CD8 r = 0.548 P = 0.0102). We assume there is the responsibility of the expression of lymphocytes, not only type but also as quantity, in determining RL or WL manifestation of OLP. Circulating lymphocytes may have a role, too. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Opioid and GABAB receptors differentially couple to an adenylyl cyclase/protein kinase A downstream effector after chronic morphine treatment.

    Directory of Open Access Journals (Sweden)

    Elena Elizabeth Bagley

    2014-06-01

    Full Text Available Opioids are intensely addictive, and cessation of their chronic use is associated with a highly aversive withdrawal syndrome. A cellular hallmark of withdrawal is an opioid sensitive protein kinase A-dependent increase in GABA transporter-1 (GAT-1 currents in periaqueductal gray (PAG neurons. Elevated GAT-1 activity directly increases GABAergic neuronal excitability and synaptic GABA release, which will enhance GABAergic inhibition of PAG output neurons. This reduced activity of PAG output neurons to several brain regions, including the hypothalamus and medulla, contributes to many of the PAG-mediated signs of opioid withdrawal. The GABAB receptor agonist baclofen reduces some of the PAG mediated signs of opioid withdrawal. Like the opioid receptors the GABAB receptor is a Gi/Go coupled G-protein coupled receptor. This suggests it could be modulating GAT-1 activity in PAG neurons through its inhibition of the adenylyl cyclase/protein kinase A pathway. Opioid modulation of the GAT-1 activity can be detected by changes in the reversal potential of opioid membrane currents. We found that when opioids are reducing the GAT-1 cation conductance and increasing the GIRK conductance the opioid agonist reversal potential is much more negative than Ek. Using this approach for GABAB receptors we show that the GABAB receptor agonist, baclofen, does not couple to inhibition of GAT-1 currents during opioid withdrawal. It is possible this differential signaling of the two Gi/Go coupled G-protein coupled receptors is due to the strong compartmentalization of the GABAB receptor that does not favor signaling to the adenylyl cyclase/protein kinase A/GAT-1 pathway. This highlights the importance of studying the effects of G-protein coupled receptors in native tissue with endogenous G-protein coupled receptors and the full complement of relevant proteins and signaling molecules. This study suggests that baclofen reduces opioid withdrawal symptoms through a non-GAT-1

  9. Subversion of the Endocytic and Secretory Pathways by Bacterial Effector Proteins

    Directory of Open Access Journals (Sweden)

    Mary M. Weber

    2018-01-01

    Full Text Available Intracellular bacteria have developed numerous strategies to hijack host vesicular trafficking pathways to form their unique replicative niches. To promote intracellular replication, the bacteria must interact with host organelles and modulate host signaling pathways to acquire nutrients and membrane for the growing parasitophorous vacuole all while suppressing activation of the immune response. To facilitate host cell subversion, bacterial pathogens use specialized secretion systems to deliver bacterial virulence factors, termed effectors, into the host cell that mimic, agonize, and/or antagonize the function of host proteins. In this review we will discuss how bacterial effector proteins from Coxiella burnetii, Brucella abortus, Salmonella enterica serovar Typhimurium, Legionella pneumophila, Chlamydia trachomatis, and Orientia tsutsugamushi manipulate the endocytic and secretory pathways. Understanding how bacterial effector proteins manipulate host processes not only gives us keen insight into bacterial pathogenesis, but also enhances our understanding of how eukaryotic membrane trafficking is regulated.

  10. Structural basis for sequence-specific recognition of DNA by TAL effectors

    KAUST Repository

    Deng, Dong

    2012-01-05

    TAL (transcription activator-like) effectors, secreted by phytopathogenic bacteria, recognize host DNA sequences through a central domain of tandem repeats. Each repeat comprises 33 to 35 conserved amino acids and targets a specific base pair by using two hypervariable residues [known as repeat variable diresidues (RVDs)] at positions 12 and 13. Here, we report the crystal structures of an 11.5-repeat TAL effector in both DNA-free and DNA-bound states. Each TAL repeat comprises two helices connected by a short RVD-containing loop. The 11.5 repeats form a right-handed, superhelical structure that tracks along the sense strand of DNA duplex, with RVDs contacting the major groove. The 12th residue stabilizes the RVD loop, whereas the 13th residue makes a base-specific contact. Understanding DNA recognition by TAL effectors may facilitate rational design of DNA-binding proteins with biotechnological applications.

  11. Brucella Modulates Secretory Trafficking via Multiple Type IV Secretion Effector Proteins

    Science.gov (United States)

    Myeni, Sebenzile; Child, Robert; Ng, Tony W.; Kupko, John J.; Wehrly, Tara D.; Porcella, Stephen F.; Knodler, Leigh A.; Celli, Jean

    2013-01-01

    The intracellular pathogenic bacterium Brucella generates a replicative vacuole (rBCV) derived from the endoplasmic reticulum via subversion of the host cell secretory pathway. rBCV biogenesis requires the expression of the Type IV secretion system (T4SS) VirB, which is thought to translocate effector proteins that modulate membrane trafficking along the endocytic and secretory pathways. To date, only a few T4SS substrates have been identified, whose molecular functions remain unknown. Here, we used an in silico screen to identify putative T4SS effector candidate proteins using criteria such as limited homology in other bacterial genera, the presence of features similar to known VirB T4SS effectors, GC content and presence of eukaryotic-like motifs. Using β-lactamase and CyaA adenylate cyclase reporter assays, we identified eleven proteins translocated into host cells by Brucella, five in a VirB T4SS-dependent manner, namely BAB1_0678 (BspA), BAB1_0712 (BspB), BAB1_0847 (BspC), BAB1_1671 (BspE) and BAB1_1948 (BspF). A subset of the translocated proteins targeted secretory pathway compartments when ectopically expressed in HeLa cells, and the VirB effectors BspA, BspB and BspF inhibited protein secretion. Brucella infection also impaired host protein secretion in a process requiring BspA, BspB and BspF. Single or combined deletions of bspA, bspB and bspF affected Brucella ability to replicate in macrophages and persist in the liver of infected mice. Taken together, these findings demonstrate that Brucella modulates secretory trafficking via multiple T4SS effector proteins that likely act coordinately to promote Brucella pathogenesis. PMID:23950720

  12. Alteration of lymphocyte functions by 8-methoxypsoralen and longwave ultraviolet radiation. I. Suppressive effects of PUVA on T-lymphocyte migration in vitro

    International Nuclear Information System (INIS)

    Okamoto, H.; Takigawa, M.; Horio, T.

    1985-01-01

    We investigated the influence of 8-methoxypsoralen (8-MOP) plus long-wave ultraviolet radiation (PUVA) on lymphocyte migration in vitro. Nylon wool-purified, mouse splenic T lymphocytes showed locomotive responses to casein, normal mouse serum (NMS), and zymosan-activated mouse serum (ZAS). Migratory responses to casein and NMS, and to ZAS were remarkably suppressed in lymphocytes exposed to 0.5 J/cm2 UVA plus 0.1 micrograms/ml 8-MOP and to 0.8 J/cm2 UVA plus 8-MOP, respectively. The PUVA treatment used in the present study had no effect on random movement and lymphocyte viability. T lymphocytes cultured in the absence of mitogenic agent for 24 h demonstrated a greater increase in their migration activity than noncultured cells, while lymphocytes cultured after 1.0 J/cm2 PUVA pretreatment remained low. These findings suggest that the therapeutic effect of PUVA on inflammatory skin disorders may be due in part to the suppression of lymphocyte migration

  13. The pattern recognition molecule ficolin-1 exhibits differential binding to lymphocyte subsets, providing a novel link between innate and adaptive immunity

    DEFF Research Database (Denmark)

    Genster, Ninette; Ma, Ying Jie; Munthe-Fog, Lea

    2014-01-01

    is unknown. Recognition of healthy host cells by a pattern recognition molecule constitutes a potential hazard to self cells and tissues, emphasizing the importance of further elucidating the reported self-recognition. In the current study we investigated the potential recognition of lymphocytes by ficolin-1...... and demonstrated that CD56(dim) NK-cells and both CD4(+) and CD8(+) subsets of activated T-cells were recognized by ficolin-1. In contrast we did not detect binding of ficolin-1 to CD56(bright) NK-cells, NKT-cells, resting T-cells or B-cells. Furthermore, we showed that the protein-lymphocyte interaction occurred...

  14. Identification of antibody glycosylation structures that predict monoclonal antibody Fc-effector function.

    Science.gov (United States)

    Chung, Amy W; Crispin, Max; Pritchard, Laura; Robinson, Hannah; Gorny, Miroslaw K; Yu, Xiaojie; Bailey-Kellogg, Chris; Ackerman, Margaret E; Scanlan, Chris; Zolla-Pazner, Susan; Alter, Galit

    2014-11-13

    To determine monoclonal antibody (mAb) features that predict fragment crystalizable (Fc)-mediated effector functions against HIV. Monoclonal antibodies, derived from Chinese hamster ovary cells or Epstein-Barr virus-immortalized mouse heteromyelomas, with specificity to key regions of the HIV envelope including gp120-V2, gp120-V3 loop, gp120-CD4(+) binding site, and gp41-specific antibodies, were functionally profiled to determine the relative contribution of the variable and constant domain features of the antibodies in driving robust Fc-effector functions. Each mAb was assayed for antibody-binding affinity to gp140(SR162), antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP) and for the ability to bind to FcγRIIa, FcγRIIb and FcγRIIIa receptors. Antibody glycan profiles were determined by HPLC. Neither the specificity nor the affinity of the mAbs determined the potency of Fc-effector function. FcγRIIIa binding strongly predicted ADCC and decreased galactose content inversely correlated with ADCP, whereas N-glycolylneuraminic acid-containing structures exhibited enhanced ADCP. Additionally, the bi-antenary glycan arm onto which galactose was added predicted enhanced binding to FcγRIIIa and ADCC activity, independent of the specificity of the mAb. Our studies point to the specific Fc-glycan structures that can selectively promote Fc-effector functions independently of the antibody specificity. Furthermore, we demonstrated antibody glycan structures associated with enhanced ADCP activity, an emerging Fc-effector function that may aid in the control and clearance of HIV infection.

  15. Effect of postirradiation anoxia on radiosensitivity of lymphocytes

    International Nuclear Information System (INIS)

    Schrek, R.

    1976-01-01

    Radiosensitivity was measured by viable-lymphocyte counts and by uridine uptake. The viability of the lymphocytes was based on morphologic characteristics visualized by phase contrast microscopy of the cells in a special slide chamber. Low doses of x rays (10 to 1000 R) and incubation at 37 0 C killed lymphocytes in interphase with the production of pyknotic nuclei (nuclear death), and large doses (6000 R) produced nuclei with clear nucleoplasm (cytoplasmic death). Nuclear, but not cytoplasmic, death was inhibited by incubation of the irradiated cells at 27 0 C. Postirradiation anoxia had no effect on development of the nuclear and cytoplasmic death of lymphocytes irradiated with 100 to 6000 R. Anoxia had no effect on the early response of lymphocytes to phytohemagglutinin (PHA) [increase in ribonucleic acid (RNA) and protein synthesis] but inhibited completely the late effects [increase in deoxyribonucleic acid (DNA) synthesis and transformation into lymphoblastoid cells]. The PHA caused relative radioresistance of lymphocytes under aerobic conditions and, to a lesser extent, under anaerobic conditions. The slight radioresistance induced by PHA in anoxic lymphocytes apparently did not depend on an increase in DNA synthesis or on the transformation to lymphoblastoid cells

  16. Differential Micronuclei Induction in Human Lymphocyte Cultures by Imidacloprid in the Presence of Potassium Nitrate

    Directory of Open Access Journals (Sweden)

    Polychronis Stivaktakis

    2010-01-01

    Full Text Available Humans are exposed to pesticides as a consequence of their application in farming or their persistence in a variety of media, including food, water, air, soil, plants, animals, and smoke. The interaction of pesticides with environmental factors may result in the alteration of their physicochemical properties. Square wave cathodic stripping voltammetry (SW-CSV, a technique that simulates electrodynamically the cellular membrane, is used to investigate whether the presence of potassium nitrate (KNO3 in the culture medium interferes with the genotoxic behavior of imidacloprid. The cytokinesis block micronuclei (CBMN method is used to evaluate imidacloprid's genotoxicity in the absence or presence of KNO3 in the culture medium and, as a consequence, its adsorption by lymphocytes. Comparing micronuclei (MN frequencies in control and imidacloprid-treated blood cell cultures, statistically significant differences were not detected. KNO3 did not induce MN frequencies compared to control. Statistically significant differences in MN frequencies were observed when blood cell cultures were treated with imidacloprid in the presence of increasing concentrations of KNO3. SW-CSV revealed that by increasing KNO3 molarity, imidacloprid's concentration in the culture medium decreased in parallel. This finding indicates that imidacloprid is adsorbed by cellular membranes. The present study suggests a novel role of a harmless environmental factor, such as KNO3, on the genotoxic behavior of a pesticide, such as imidacloprid. KNO3 rendered imidacloprid permeable to lymphocytes, resulting in elevated MN frequencies.

  17. The IL23R R381Q gene variant protects against immune-mediated diseases by impairing IL-23-induced Th17 effector response in humans.

    Directory of Open Access Journals (Sweden)

    Paola Di Meglio

    2011-02-01

    Full Text Available IL-23 and Th17 cells are key players in tissue immunosurveillance and are implicated in human immune-mediated diseases. Genome-wide association studies have shown that the IL23R R381Q gene variant protects against psoriasis, Crohn's disease and ankylosing spondylitis. We investigated the immunological consequences of the protective IL23R R381Q gene variant in healthy donors. The IL23R R381Q gene variant had no major effect on Th17 cell differentiation as the frequency of circulating Th17 cells was similar in carriers of the IL23R protective (A and common (G allele. Accordingly, Th17 cells generated from A and G donors produced similar amounts of Th17 cytokines. However, IL-23-mediated Th17 cell effector function was impaired, as Th17 cells from A allele carriers had significantly reduced IL-23-induced IL-17A production and STAT3 phosphorylation compared to G allele carriers. Our functional analysis of a human disease-associated gene variant demonstrates that IL23R R381Q exerts its protective effects through selective attenuation of IL-23-induced Th17 cell effector function without interfering with Th17 differentiation, and highlights its importance in the protection against IL-23-induced tissue pathologies.

  18. The IL23R R381Q gene variant protects against immune-mediated diseases by impairing IL-23-induced Th17 effector response in humans.

    Science.gov (United States)

    Di Meglio, Paola; Di Cesare, Antonella; Laggner, Ute; Chu, Chung-Ching; Napolitano, Luca; Villanova, Federica; Tosi, Isabella; Capon, Francesca; Trembath, Richard C; Peris, Ketty; Nestle, Frank O

    2011-02-22

    IL-23 and Th17 cells are key players in tissue immunosurveillance and are implicated in human immune-mediated diseases. Genome-wide association studies have shown that the IL23R R381Q gene variant protects against psoriasis, Crohn's disease and ankylosing spondylitis. We investigated the immunological consequences of the protective IL23R R381Q gene variant in healthy donors. The IL23R R381Q gene variant had no major effect on Th17 cell differentiation as the frequency of circulating Th17 cells was similar in carriers of the IL23R protective (A) and common (G) allele. Accordingly, Th17 cells generated from A and G donors produced similar amounts of Th17 cytokines. However, IL-23-mediated Th17 cell effector function was impaired, as Th17 cells from A allele carriers had significantly reduced IL-23-induced IL-17A production and STAT3 phosphorylation compared to G allele carriers. Our functional analysis of a human disease-associated gene variant demonstrates that IL23R R381Q exerts its protective effects through selective attenuation of IL-23-induced Th17 cell effector function without interfering with Th17 differentiation, and highlights its importance in the protection against IL-23-induced tissue pathologies.

  19. Strong antitumor activities of IgG3 antibodies to a human melanoma-associated ganglioside

    International Nuclear Information System (INIS)

    Hellstroem, I.; Brankovan, V.; Hellstroem, K.E.

    1985-01-01

    Three mouse monoclonal IgG3 antibodies, 2B2, IF4, and MG-21, recognize a G/sub D3/ ganglioside antigen that is expressed at the cell surface of most human melanomas. All three antibodies mediate antibody-dependent cellular cytotoxicity (ADCC) in vitro when tested with human lymphocytes or effector cells in a 2-hr or 4-hr 51 Cr-release test, and one antibody, MG-21, also gives strong complement-dependent cytotoxicity with human serum. Antibody 2B2, which gives ADDC also in the presence of mouse lymphocytes, inhibited the outgrowth of a human melanoma in nude mice, but antibody IF4, which showed no ADCC with mouse lymphocyte effectors, did not

  20. High immunosuppressive burden in advanced hepatocellular carcinoma patients: Can effector functions be restored?

    Science.gov (United States)

    Lugade, Amit A; Kalathil, Suresh; Miller, Austin; Iyer, Renuka; Thanavala, Yasmin

    2013-07-01

    The accumulation of immunosuppressive cells and exhausted effector T cells highlight an important immune dysfunction in advanced stage hepatocellular carcinoma (HCC) patients. These cells significantly hamper the efficacy immunotherapies and facilitate HCC progression. We have recently demonstrated that the multipronged depletion of immunosuppressive cells potentially restores effector T-cell function in HCC.

  1. Phase I-II study of lenalidomide and alemtuzumab in refractory chronic lymphocytic leukemia (CLL): effects on T cells and immune checkpoints.

    Science.gov (United States)

    Winqvist, Maria; Mozaffari, Fariba; Palma, Marzia; Eketorp Sylvan, Sandra; Hansson, Lotta; Mellstedt, Håkan; Österborg, Anders; Lundin, Jeanette

    2017-01-01

    This phase I-II study explored safety, immunomodulatory and clinical effects of lenalidomide (weeks 1-16) and alemtuzumab (weeks 5-16) in 23 patients with refractory chronic lymphocytic leukemia. Most patients had Rai stage III/IV disease and were heavily pretreated (median 4 prior therapies), and 61% had del(17p)/del(11q). Eleven of 19 evaluable patients (58%) responded, with a median response duration of 12 months (1-29+); time to progression was short in non-responders. Lenalidomide had a narrow therapeutic dose range, 2.5 mg/day was not efficient, and maximum tolerated dose was 5 mg/day. Grade 3-4 neutropenia and thrombocytopenia occurred in 84 and 55%, 30% had febrile neutropenia, and CMV-reactivation requiring valganciclovir occurred in 30% of patients. The frequency of proliferating (Ki67 + ) CD8 + T cells was increased at week 4, with further increase in both the CD4 + and CD8 + subsets (p cells increased at week 4 as the frequency of effector memory cells increased in the CD8 + subset (p cells decreased in both the CD8 + and CD4 + subsets (p regulatory T cells was reduced (p T cells decreased, and effector memory T cells increased (p T cells increased at 30-week follow-up (p T cells, including increased proliferative activity and cytotoxic potential.

  2. The pore-forming bacterial effector, VopQ, halts autophagic turnover.

    Science.gov (United States)

    Sreelatha, Anju; Orth, Kim; Starai, Vincent J

    2013-12-01

    Vibrio parahemolyticus Type III effector VopQ is both necessary and sufficient to induce autophagy within one hour of infection. We demonstrated that VopQ interacts with the Vo domain of the conserved vacuolar H(+)-ATPase. Membrane-associated VopQ subsequently forms pores in the membranes of acidic compartments, resulting in immediate release of protons without concomitant release of lumenal protein contents. These studies show how a bacterial pathogen can compromise host ion potentials using a gated pore-forming effector to equilibrate levels of small molecules found in endolysosomal compartments and disrupt cellular processes such as autophagy.

  3. Nanotopographical Control of Stem Cell Differentiation

    Directory of Open Access Journals (Sweden)

    Laura E. McNamara

    2010-01-01

    Full Text Available Stem cells have the capacity to differentiate into various lineages, and the ability to reliably direct stem cell fate determination would have tremendous potential for basic research and clinical therapy. Nanotopography provides a useful tool for guiding differentiation, as the features are more durable than surface chemistry and can be modified in size and shape to suit the desired application. In this paper, nanotopography is examined as a means to guide differentiation, and its application is described in the context of different subsets of stem cells, with a particular focus on skeletal (mesenchymal stem cells. To address the mechanistic basis underlying the topographical effects on stem cells, the likely contributions of indirect (biochemical signal-mediated and direct (force-mediated mechanotransduction are discussed. Data from proteomic research is also outlined in relation to topography-mediated fate determination, as this approach provides insight into the global molecular changes at the level of the functional effectors.

  4. Rho GTPases in ameloblast differentiation

    Directory of Open Access Journals (Sweden)

    Keishi Otsu

    2016-05-01

    Full Text Available During tooth development, ameloblasts differentiate from inner enamel epithelial cells to enamel-forming cells by modulating the signal pathways mediating epithelial–mesenchymal interaction and a cell-autonomous gene network. The differentiation process of epithelial cells is characterized by marked changes in their morphology and polarity, accompanied by dynamic cytoskeletal reorganization and changes in cell–cell and cell–matrix adhesion over time. Functional ameloblasts are tall, columnar, polarized cells that synthesize and secrete enamel-specific proteins. After deposition of the full thickness of enamel matrix, ameloblasts become smaller and regulate enamel maturation. Recent significant advances in the fields of molecular biology and genetics have improved our understanding of the regulatory mechanism of the ameloblast cell life cycle, mediated by the Rho family of small GTPases. They act as intracellular molecular switch that transduce signals from extracellular stimuli to the actin cytoskeleton and the nucleus. In our review, we summarize studies that provide current evidence for Rho GTPases and their involvement in ameloblast differentiation. In addition to the Rho GTPases themselves, their downstream effectors and upstream regulators have also been implicated in ameloblast differentiation.

  5. Modulating Cytotoxic Effector Functions by Fc Engineering to Improve Cancer Therapy.

    Science.gov (United States)

    Kellner, Christian; Otte, Anna; Cappuzzello, Elisa; Klausz, Katja; Peipp, Matthias

    2017-09-01

    In the last two decades, monoclonal antibodies have revolutionized the therapy of cancer patients. Although antibody therapy has continuously been improved, still a significant number of patients do not benefit from antibody therapy. Therefore, rational optimization of the antibody molecule by Fc engineering represents a major area of translational research to further improve this potent therapeutic option. Monoclonal antibodies are able to trigger a variety of effector mechanisms. Especially Fc-mediated effector functions such as antibody-dependent cell-mediated cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP), and complement- dependent cytotoxicity (CDC) are considered important in antibody therapy of cancer. Novel mechanistic insights into the action of monoclonal antibodies allowed the development of various Fc engineering approaches to modulate antibodies' effector functions. Strategies in modifying the Fc glycosylation profile (Fc glyco-engineering) or approaches in engineering the protein backbone (Fc protein engineering) have been intensively evaluated. In the current review, Fc engineering strategies resulting in improved ADCC, ADCP and CDC activity are summarized and discussed.

  6. Role of Rab family GTPases and their effectors in melanosomal logistics.

    Science.gov (United States)

    Ohbayashi, Norihiko; Fukuda, Mitsunori

    2012-04-01

    Rab GTPases constitute a family of small GTPases that regulate a variety of membrane trafficking events in all eukaryotic cells by recruiting their specific effector molecules. Recent accumulating evidence indicates that members of the mammalian Rab small GTPase family are involved in certain physiological and pathological processes. In particular, functional impairments of specific Rab proteins, e.g. Rab38 and Rab27A, their regulators or their effectors cause pigmentation disorders in humans and coat colour variations in mice because such impairments cause defects in melanosomal logistics, i.e. defects in melanosome biogenesis and transport. Genetic and biochemical analyses of the gene products responsible for mammalian pigmentation disorders in the past decade have revealed that Rab-mediated endosomal transport systems and melanosome transport systems play crucial roles in the efficient darkening of mammalian hair and skin. In this article, we review current knowledge regarding melanosomal logistics, with particular focus on the roles of Rab small GTPases and their effectors.

  7. The behavior of pig lymphocyte populations in vivo

    International Nuclear Information System (INIS)

    Binns, R.M.; Licence, S.T.; Pabst, R.

    1986-01-01

    Lymphocyte migration provides the means of rapidly recognizing and responding to antigen and widely disseminating the resulting immune response. The porcine lymphoid system differs from that of man in structural inversion of lymph nodes and route of lymphocyte recirculation and the existence of two Peyer's patch types, one of which differs from the conventional pattern in structure, cell content and lack of lymphocyte traffic and in its regression in old age. Recirculating T and B lymphocytes enter and leave spleen and lymph nodes by the blood but Null cells do not; lymphocytes also migrate through nonlymphoid tissues. The lung is one such important site, with a small migration in and out of alveolar space and a large traffic associated with the blood vessel wall, predominantly involving T cells. Blood lymphocytes hardly traffic into the peritoneal cavity, yet major traffic of particulate material or cells is possible in this important site of abdominal defense, so often used for immunization, and follows a distinct, well defined route. Cells migrate out of subcutaneous tissue via the draining node. Lymphocytes are produced and emigrate into blood from labelled thymus. They differ in size and surface phenotype from both thymocytes and peripheral T cells. Lymphocytes also migrate from blood into most tissues. In most nonlymphoid tissues, entry relates to blood flow but in many lymphoid tissues it is an active process which differs in tempo and extent, eg, between different nodes and between the two Peyer's patch types

  8. Cell volume homeostatic mechanisms: effectors and signalling pathways

    DEFF Research Database (Denmark)

    Hoffmann, E K; Pedersen, Stine Helene Falsig

    2011-01-01

    . Later work addressed the mechanisms through which cellular signalling pathways regulate the volume regulatory effectors or flux pathways. These studies were facilitated by the molecular identification of most of the relevant channels and transporters, and more recently also by the increased...

  9. Alkylglycerols modulate the proliferation and differentiation of non-specific agonist and specific antigen-stimulated splenic lymphocytes.

    Directory of Open Access Journals (Sweden)

    Linxi Qian

    Full Text Available Alkylglycerols (AKGs are ether-linked glycerols derived from shark liver oil and found in small amounts in human milk. Previous studies showed that oral AKGs administration significantly increased the immune response in mice. The aim of the present study was to investigate the in vitro immunomodulatory effect of AKGs on stimulating splenic lymphocyte responses. C57BL/6 mice were immunized with hepatitis B surface antigen (HBsAg. Splenic B cells were purified and stimulated with anti-BCR and anti-CD38. Meanwhile, splenic CD4+ T cells were purified and stimulated with anti-CD3 and anti-CD28. For antigen specific stimulation, the purified CD4+ T cells were cocultured with HBsAg -pulsed dendritic cells. The stimulated lymphocytes were treated with different concentrations of AKGs. The cell proliferation was assessed by [3H]-thymidine incorporation assay. The maturation of B cells was assessed by examining the germline (GL transcription of IgG (γ1 mRNA expression, and the surface expressions of CD80/CD86 markers were examined by flow cytometry analysis. Th1/Th2 polarity was assessed by T-BET (Th1/GATA-3 (Th2 flow cytometry assay and by characteristic cytokines ELISA assay (TNF-α and IFN-γ for Th1; IL-4 and IL-10 for Th2. It was found that AKGs significantly increased the BCR/CD38 -stimulated B cell proliferation. The T cell proliferation in response to CD3/CD28 or specific antigen stimulation was also increased by AKGs. The transcriptional level of IgG (γ1 and the expressions of CD80/CD86 molecules were markedly increased by AKGs in BCR/CD38 -stimulated B cells. Meanwhile, the results showed that AKGs increased the expression of T-BET transcriptional factor and the production of Th1 cytokines (TNF-α and IFN-γ upon CD3/CD28 stimulation; whereas, levels of Th2 cytokines (IL-4 and IL-10 were decreased by AKGs. Our study demonstrated that AKGs can modulate immune responses by boosting the proliferation and maturation of murine lymphocytes in vitro.

  10. The Salmonella effector protein SpvC, a phosphothreonine lyase is functional in plant cells

    Directory of Open Access Journals (Sweden)

    Christina eNeumann

    2014-10-01

    Full Text Available Salmonella is one of the most prominent causes of food poisoning and growing evidence indicates that contaminated fruits and vegetables are an increasing concern for human health. Successful infection demands the suppression of the host immune system, which is often achieved via injection of bacterial effector proteins into host cells. In this report we present the function of Salmonella effector protein in plant cell, supporting the new concept of trans-kingdom competence of this bacterium. We screened a range of Salmonella Typhimurium effector proteins for interference with plant immunity. Among these, the phosphothreonine lyase SpvC attenuated the induction of immunity-related genes when present in plant cells. Using in vitro and in vivo systems we show that this effector protein interacts with and dephosphorylates activated Arabidopsis Mitogen-activated Protein Kinase 6 (MPK6, thereby inhibiting defense signaling. Moreover, the requirement of Salmonella SpvC was shown by the decreased proliferation of the ΔspvC mutant in Arabidopsis plants. These results suggest that some Salmonella effector proteins could have a conserved function during proliferation in different hosts. The fact that Salmonella and other Enterobacteriaceae use plants as hosts strongly suggests that plants represent a much larger reservoir for animal pathogens than so far estimated.

  11. The Salmonella effector protein SpvC, a phosphothreonine lyase is functional in plant cells

    KAUST Repository

    Neumann, Christina

    2014-10-17

    Salmonella is one of the most prominent causes of food poisoning and growing evidence indicates that contaminated fruits and vegetables are an increasing concern for human health. Successful infection demands the suppression of the host immune system, which is often achieved via injection of bacterial effector proteins into host cells. In this report we present the function of Salmonella effector protein in plant cell, supporting the new concept of trans-kingdom competence of this bacterium. We screened a range of Salmonella Typhimurium effector proteins for interference with plant immunity. Among these, the phosphothreonine lyase SpvC attenuated the induction of immunity-related genes when present in plant cells. Using in vitro and in vivo systems we show that this effector protein interacts with and dephosphorylates activated Arabidopsis Mitogen-activated Protein Kinase 6 (MPK6), thereby inhibiting defense signaling. Moreover, the requirement of Salmonella SpvC was shown by the decreased proliferation of the ΔspvC mutant in Arabidopsis plants. These results suggest that some Salmonella effector proteins could have a conserved function during proliferation in different hosts. The fact that Salmonella and other Enterobacteriaceae use plants as hosts strongly suggests that plants represent a much larger reservoir for animal pathogens than so far estimated.

  12. 2SNP heritability and effects of genetic variants for neutrophil-to-lymphocyte and platelet-to-lymphocyte ratio

    NARCIS (Netherlands)

    Lin, Bochao Danae; Carnero-Montoro, Elena; Bell, Jordana T; Boomsma, Dorret I; de Geus, Eco J; Jansen, Rick; Kluft, Cornelis; Mangino, Massimo; Penninx, Brenda; Spector, Tim D; Willemsen, Gonneke; Hottenga, Jouke-Jan

    2017-01-01

    Neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are important biomarkers for disease development and progression. To gain insight into the genetic causes of variance in NLR and PLR in the general population, we conducted genome-wide association (GWA) analyses and

  13. Separation and properties of EA-rosette-forming lymphocytes in humans

    NARCIS (Netherlands)

    van Oers, M. H.; Zeijlemaker, W. P.; Schellekens, P. T.

    1977-01-01

    Human peripheral blood lymphocytes were separated into subpopulations enriched or depleted with respect to B lymphocytes (Ig-bearing cells), T lymphocytes, (cell forming rosettes with sheep erythrocytes: E-RFC) and Fc receptor-bearing lymphocytes (EA-RFC). From the distributions and recoveries of

  14. A three-dimensional approach to in vitro culture of immune-related cells

    DEFF Research Database (Denmark)

    Hartmann, Sofie Bruun

    setups for improved activation/differentiation of immune cells. Conclusively, this work highlights the importance of acknowledging the effect from external factors when analyzing data generated from in vitro cultures. This being even more important when working with immune cells since these cells adopt......T lymphocytes are key players during the initiation of an adaptive immune response. The activation of these cells in vivo requires migration within the lymph nodes until they encounter antigen presenting cells (APCs) that can activate them to secrete IFN-γ which mediates downstream effector...... functions. The in vitro reactivation of antigen-experienced T lymphocytes and detection of IFN-γ from cell cultures can be used in a diagnostic assay to test for disease or vaccine efficacy. Practical procedures of the IFN-γ release assay (IGRA) was investigated using bovine cells and whole blood cultures...

  15. Interleukin 2 secretion by lectin-activated human blood lymphocytes is markedly augmented by vascular endothelial cells

    International Nuclear Information System (INIS)

    Guinan, E.C.; Pober, J.S.

    1986-01-01

    Since the initial interaction (and possible activation) of a blood borne T lymphocyte involves contact with the endothelial lining of the vasculature at the site of an immune response, the authors have examined the effect of cultured human endothelial cells (HEC) upon polyclonal T cell activation. Addition of 10 4 HEC to 10 4 -10 5 peripheral blood lymphocytes (PBL) stimulated with phytohemagglutinin (PHA, 0.3-10 μg/ml) leads to marked augmentation of interleukin 2 (IL-2) production. The relative increase in IL-2 (mean of 3 expts. +/- SEM) is present at 24 h (5.8 fold +/- 1.5) and become more marked at 48 h (12.6 fold +/- 3.5) and 72 h (18.5 fold +/- 3.7). This relative enhancement is greater for HEC added to 10 4 than 10 5 PBL and is also greater when 10 4 rather than 2 x 10 3 HEC are added to a given number of PBL. This increased IL-2 concentration has two biological consequences. First, at suboptimal PHA doses or at low PBL number, PBL proliferation as measured by 3 H-thymidine incorporation is increased up to two fold. Second, the phenotype of the proliferating cells appears altered, including a decrease in mean density of IL-2 receptor. The authors hypothesize that such modulation of the concentration of locally produced IL-2 may play a key role in the nature of an immune response, influencing both its magnitude and the functional profile of the activated and amplified effector cells

  16. A novel adoptive transfer model of chronic lymphocytic leukemia suggests a key role for T lymphocytes in the disease

    OpenAIRE

    Bagnara, Davide; Kaufman, Matthew S.; Calissano, Carlo; Marsilio, Sonia; Patten, Piers E. M.; Simone, Rita; Chum, Philip; Yan, Xiao-Jie; Allen, Steven L.; Kolitz, Jonathan E.; Baskar, Sivasubramanian; Rader, Christoph; Mellstedt, Hakan; Rabbani, Hodjattallah; Lee, Annette

    2011-01-01

    Chronic lymphocytic leukemia (CLL) is an incurable adult disease of unknown etiology. Understanding the biology of CLL cells, particularly cell maturation and growth in vivo, has been impeded by lack of a reproducible adoptive transfer model. We report a simple, reproducible system in which primary CLL cells proliferate in nonobese diabetes/severe combined immunodeficiency/γcnull mice under the influence of activated CLL-derived T lymphocytes. By cotransferring autologous T lymphocytes, activ...

  17. γδ T LYMPHOCYTES AS A FIRST LINE OF IMMUNE DEFENSE: OLD AND NEW WAYS OF ANTIGEN RECOGNITION AND IMPLICATIONS FOR CANCER IMMUNOTHERAPY.

    Directory of Open Access Journals (Sweden)

    Maria Raffaella eZocchi

    2014-11-01

    Full Text Available Among γδT cells, the Vδ1 subset, resident in epithelial tissues, is implied in the defense against viruses, fungi and certain hematological malignancies, while the circulating Vδ2 subpopulation mainly respond to mycobacteria and solid tumors. Both subsets can be activated by stress-induced molecules (MIC-A, MIC-B, ULBPs to produce pro-inflammatory cytokines and lytic enzymes and destroy bacteria or damaged cells. γδT lymphocytes can also recognize lipids, as those associated to M. tuberculosis, presented by the CD1 molecule, or phosphoantigens (P-Ag, either autologous, which accumulates in virus-infected cells, or microbial produced by prokaryotes and parasites. In cancer cells P-Ag accumulate due to alterations in the mevalonate pathway; recently, butyrophilin 3A1 has been shown to be the presenting molecule for P-Ag. Of interest, aminobisphosphonates indirectly activate Vδ2 T cells inducing the accumulation of P-Ag. Based on these data, γδT lymphocytes are attractive effectors for cancer immunotherapy. However, the results obtained in clinical trials so far have been disappointing: this review will focus on the possible reasons of this failure as well as on suggestions for implementation of the therapeutic strategies.

  18. Actin Cytoskeleton Manipulation by Effector Proteins Secreted by Diarrheagenic Escherichia coli Pathotypes

    Directory of Open Access Journals (Sweden)

    Fernando Navarro-Garcia

    2013-01-01

    Full Text Available The actin cytoskeleton is a dynamic structure necessary for cell and tissue organization, including the maintenance of epithelial barriers. Disruption of the epithelial barrier coincides with alterations of the actin cytoskeleton in several disease states. These disruptions primarily affect the paracellular space, which is normally regulated by tight junctions. Thereby, the actin cytoskeleton is a common and recurring target of bacterial virulence factors. In order to manipulate the actin cytoskeleton, bacteria secrete and inject toxins and effectors to hijack the host cell machinery, which interferes with host-cell pathways and with a number of actin binding proteins. An interesting model to study actin manipulation by bacterial effectors is Escherichia coli since due to its genome plasticity it has acquired diverse genetic mobile elements, which allow having different E. coli varieties in one bacterial species. These E. coli pathotypes, including intracellular and extracellular bacteria, interact with epithelial cells, and their interactions depend on a specific combination of virulence factors. In this paper we focus on E. coli effectors that mimic host cell proteins to manipulate the actin cytoskeleton. The study of bacterial effector-cytoskeleton interaction will contribute not only to the comprehension of the molecular causes of infectious diseases but also to increase our knowledge of cell biology.

  19. An Aphid Effector Targets Trafficking Protein VPS52 in a Host-Specific Manner to Promote Virulence1[OPEN

    Science.gov (United States)

    2017-01-01

    Plant- and animal-feeding insects secrete saliva inside their hosts, containing effectors, which may promote nutrient release and suppress immunity. Although for plant pathogenic microbes it is well established that effectors target host proteins to modulate host cell processes and promote disease, the host cell targets of herbivorous insects remain elusive. Here, we show that the existing plant pathogenic microbe effector paradigm can be extended to herbivorous insects in that effector-target interactions inside host cells modify critical host processes to promote plant susceptibility. We showed that the effector Mp1 from Myzus persicae associates with the host Vacuolar Protein Sorting Associated Protein52 (VPS52). Using natural variants, we provide a strong link between effector virulence activity and association with VPS52, and show that the association is highly specific to M. persicae-host interactions. Also, coexpression of Mp1, but not Mp1-like variants, specifically with host VPS52s resulted in effector relocalization to vesicle-like structures that associate with prevacuolar compartments. We show that high VPS52 levels negatively impact virulence, and that aphids are able to reduce VPS52 levels during infestation, indicating that VPS52 is an important virulence target. Our work is an important step forward in understanding, at the molecular level, how a major agricultural pest promotes susceptibility during infestation of crop plants. We give evidence that an herbivorous insect employs effectors that interact with host proteins as part of an effective virulence strategy, and that these effectors likely function in a species-specific manner. PMID:28100451

  20. Combination of neutrophil lymphocyte ratio and platelet lymphocyte ratio is a useful predictor of postoperative survival in patients with esophageal squamous cell carcinoma

    Directory of Open Access Journals (Sweden)

    Feng JF

    2013-11-01

    Full Text Available Ji-Feng Feng,1 Ying Huang,2 Jin-Shi Liu1 1Department of Thoracic Surgery, 2Department of Operating Theatre, Zhejiang Cancer Hospital, Hangzhou, People's Republic of China Background: Recent studies have shown that the presence of systemic inflammation correlates with poor survival in various types of cancers. This study investigated the usefulness of a novel inflammation-based prognostic system, using the combination of neutrophil lymphocyte ratio (NLR and platelet lymphocyte ratio (PLR, collectively named the CNP, for predicting survival in patients with esophageal squamous cell carcinoma (ESCC. Materials and methods: The CNP was calculated on the basis of data obtained on the day of admission: patients with both elevated NLR (>3.45 and PLR (>166.5 were allocated a score of 2, and patients showing one or neither were allocated a score of 1 or 0, respectively. Results: The CNP was associated with tumor length (P<0.001, differentiation (P=0.021, depth of invasion (P<0.001, and nodal metastasis (P<0.001. No significant differences were found between the CNP and morbidity. However, significant differences were found between the CNP and mortality (P<0.001. The overall survival in the CNP 0, CNP 1, and CNP 2 groups were 63.4%, 50.0%, and 20.2%, respectively (CNP 0 versus CNP 1, P=0.014; CNP 1 versus CNP 2, P<0.001. Multivariate analyses showed that CNP was a significant predictor of overall survival. CNP 1–2 had a hazard ratio (HR of 1.964 (95% confidence interval [CI]: 1.371–2.814, P<0.001 for overall survival. CNP (HR =1.964, P<0.001 is superior to NLR (HR =1.310, P=0.053 or PLR (HR =1.751, P<0.001 as a predictive factor. Conclusion: The CNP is considered a useful predictor of postoperative survival in patients with ESCC. The CNP is superior to NLR or PLR as a predictive factor in patients with ESCC. Keywords: esophageal squamous cell carcinoma (ESCC, neutrophil lymphocyte ratio (NLR, platelet lymphocyte ratio (PLR, overall survival

  1. γδ T lymphocytes from cystic fibrosis patients and healthy donors are high TNF-α and IFN-γ-producers in response to Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Martínez Natalia

    2003-09-01

    Full Text Available Abstract Background γδ T cells have an important immunoregulatory and effector function through cytokine release. They are involved in the responses to Gram-negative bacterium and in protection of lung epithelium integrity. On the other hand, they have been implicated in airway inflammation. Methods The aim of the present work was to study intracytoplasmic IL-2, IL-4, IFN-γ and TNF-α production by γδ and αβ T lymphocytes from cystic fibrosis patients and healthy donors in response to Pseudomonas aeruginosa (PA. Flow cytometric detection was performed after peripheral blood mononuclear cells (PBMC culture with a cytosolic extract from PA and restimulation with phorbol ester plus ionomycine. Proliferative responses, activation markers and receptor usage of γδ T cells were also evaluated. Results The highest production of cytokine was of TNF-α and IFN-γ, γδ being better producers than αβ. No differences were found between patients and controls. The Vγ9δ2 subset of γδ T cells was preferentially expanded. CD25 and CD45RO expression by the αβ T subset and PBMC proliferative response to PA were defective in cystic fibrosis lymphocytes. Conclusion Our results support the hypothesis that γδ T lymphocytes play an important role in the immune response to PA and in the chronic inflammatory lung reaction in cystic fibrosis patients. They do not confirm the involvement of a supressed Th1 cytokine response in the pathogenesis of this disease.

  2. Selective toxicity of persian gulf sea cucumber holothuria parva on human chronic lymphocytic leukemia b lymphocytes by direct mitochondrial targeting.

    Science.gov (United States)

    Salimi, Ahmad; Motallebi, Abbasali; Ayatollahi, Maryam; Seydi, Enayatollah; Mohseni, Ali Reza; Nazemi, Melika; Pourahmad, Jalal

    2017-04-01

    Natural products isolated from marine environment are well known for their pharmacodynamic potential in diversity of disease treatments such as cancer or inflammatory conditions. Sea cucumbers are one of the marine animals of the phylum Echinoderm. Many studies have shown that the sea cucumber contains antioxidants and anti-cancer compounds. Chronic lymphocytic leukemia (CLL) is a disease characterized by the relentless accumulation of CD5 + B lymphocytes. CLL is the most common leukemia in adults, about 25-30% of all leukemias. In this study B lymphocytes and their mitochondria (cancerous and non-cancerous) were obtained from peripheral blood of human subjects and B lymphocyte cytotoxicity assay, and caspase 3 activation along with mitochondrial upstream events of apoptosis signaling including reactive oxygen species (ROS) production, collapse of mitochondrial membrane potential (MMP) and mitochondrial swelling were determined following the addition of Holothuria parva extract to both cancerous and non-cancerous B lymphocytes and their mitochondria. Our in vitro finding showed that mitochondrial ROS formation, MMP collapse, and mitochondrial swelling and cytochrome c release were significantly (P < 0.05) increased after addition of different concentrations of H. parva only in cancerous BUT NOT normal non-cancerous mitochondria. Consistently, different concentrations of H. parva significantly (P < 0.05) increased cytotoxicity and caspase 3 activation only in cancerous BUT NOT normal non-cancerous B lymphocytes. These results showed that H. parva methanolic extract has a selective mitochondria mediated apoptotic effect on chronic lymphocytic leukemia B lymphocytes hence may be promising in the future anticancer drug development for treatment of CLL. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1158-1169, 2017. © 2016 Wiley Periodicals, Inc.

  3. Learning-based position control of a closed-kinematic chain robot end-effector

    Science.gov (United States)

    Nguyen, Charles C.; Zhou, Zhen-Lei

    1990-01-01

    A trajectory control scheme whose design is based on learning theory, for a six-degree-of-freedom (DOF) robot end-effector built to study robotic assembly of NASA hardwares in space is presented. The control scheme consists of two control systems: the feedback control system and the learning control system. The feedback control system is designed using the concept of linearization about a selected operating point, and the method of pole placement so that the closed-loop linearized system is stabilized. The learning control scheme consisting of PD-type learning controllers, provides additional inputs to improve the end-effector performance after each trial. Experimental studies performed on a 2 DOF end-effector built at CUA, for three tracking cases show that actual trajectories approach desired trajectories as the number of trials increases. The tracking errors are substantially reduced after only five trials.

  4. Mechanism of IRSp53 inhibition and combinatorial activation by Cdc42 and downstream effectors.

    Science.gov (United States)

    Kast, David J; Yang, Changsong; Disanza, Andrea; Boczkowska, Malgorzata; Madasu, Yadaiah; Scita, Giorgio; Svitkina, Tatyana; Dominguez, Roberto

    2014-04-01

    The Rho family GTPase effector IRSp53 has essential roles in filopodia formation and neuronal development, but its regulatory mechanism is poorly understood. IRSp53 contains a membrane-binding BAR domain followed by an unconventional CRIB motif that overlaps with a proline-rich region (CRIB-PR) and an SH3 domain that recruits actin cytoskeleton effectors. Using a fluorescence reporter assay, we show that human IRSp53 adopts a closed inactive conformation that opens synergistically with the binding of human Cdc42 to the CRIB-PR and effector proteins, such as the tumor-promoting factor Eps8, to the SH3 domain. The crystal structure of Cdc42 bound to the CRIB-PR reveals a new mode of effector binding to Rho family GTPases. Structure-inspired mutations disrupt autoinhibition and Cdc42 binding in vitro and decouple Cdc42- and IRSp53-dependent filopodia formation in cells. The data support a combinatorial mechanism of IRSp53 activation.

  5. Bacterial effector HopF2 interacts with AvrPto and suppresses Arabidopsis innate immunity at the plasma membrane

    Science.gov (United States)

    Plant pathogenic bacteria inject a cocktail of effector proteins into host plant cells to modulate the host immune response, thereby promoting pathogenicity. How or whether these effectors work cooperatively is largely unknown. The Pseudomonas syringae DC3000 effector HopF2 suppresses the host plan...

  6. Absence of CD4+ T lymphocytes, CD8+ T lymphocytes, or B lymphocytes has different effects on the efficacy of posaconazole and benznidazole in treatment of experimental acute Trypanosoma cruzi infection.

    Science.gov (United States)

    Ferraz, Marcela L; Gazzinelli, Ricardo T; Alves, Rosana O; Urbina, Julio A; Romanha, Alvaro J

    2009-01-01

    We investigated the influence of CD4(+) T lymphocytes, CD8(+) T lymphocytes, and B lymphocytes on the efficacy of posaconazole (POS) and the reference drug benznidazole (BZ) during treatment of acute Trypanosoma cruzi infection in a murine model. Wild-type mice infected with T. cruzi and treated with POS or BZ presented no parasitemia, 100% survival, and 86 to 89% cure rates, defined as the percentages of animals with negative hemocultures at the end of the observation period. CD4(+)-T-lymphocyte-knockout (KO) mice infected with T. cruzi and treated with BZ or POS controlled parasitemia during treatment, although circulating parasites reappeared after drug pressure cessation, leading to only a 6% survival rate and no cure. CD8(+)-T-lymphocyte-KO mice infected with T. cruzi and treated with POS or BZ had intermediate results, displaying discrete parasitemia after the treatment was ended, 81 and 86% survival, and cure rates of 31 and 66%, respectively. B-lymphocyte-KO mice infected with T. cruzi and treated with BZ relapsed with parasitemia 1 week after the end of treatment and had a 67% survival rate and only a 22% cure rate. In contrast, the activity of POS was much less affected in these animals, with permanent suppression of parasitemia, 100% survival, and a 71% cure rate. Our results demonstrate that abrogation of different lymphocytes' activities has distinct effects on the efficacy of POS and BZ in this experimental model, probably reflecting different parasite stages preferentially targeted by the two drugs and distinct cooperation patterns with the host immune system.

  7. Lymphocyte subsets in human immunodeficiency virus-unexposed Brazilian individuals from birth to adulthood

    Directory of Open Access Journals (Sweden)

    Maria Isabel de Moraes-Pinto

    2014-12-01

    Full Text Available Ethnic origin, genetics, gender and environmental factors have been shown to influence some immunologic indices, so that development of reference values for populations of different backgrounds may be necessary. We have determined the distribution of lymphocyte subsets in healthy Brazilian individuals from birth to adulthood. Lymphocyte subsets were determined using four-colour cytometry in a cross-sectional study of 463 human immunodeficiency virus-unexposed children and adults from birth through 49 years of age. Lymphocyte subsets varied according to age, as previously observed in other studies. However, total CD4+ T cell numbers were lower than what was described in the Pediatric AIDS Clinical Trials Group P1009 (PACTG P1009, which assessed an American population of predominantly African and Hispanic backgrounds until the 12-18 year age range, when values were comparable. Naïve percentages and absolute values of CD8+ T cells, as assessed by CD45RA expression, were also lower than the PACTG P1009 data for all analysed age ranges. CD38 expression on both CD4+ and CD8+ T cells was lower than the PACTG P1009 values, with a widening gap between the two studies at older age ranges. Different patterns of cell differentiation seem to occur in different settings and may have characteristic expression within each population.

  8. miR-342-5p Regulates Neural Stem Cell Proliferation and Differentiation Downstream to Notch Signaling in Mice

    Directory of Open Access Journals (Sweden)

    Fang Gao

    2017-04-01

    Full Text Available Summary: Notch signaling is critically involved in neural development, but the downstream effectors remain incompletely understood. In this study, we cultured neurospheres from Nestin-Cre-mediated conditional Rbp-j knockout (Rbp-j cKO and control embryos and compared their miRNA expression profiles using microarray. Among differentially expressed miRNAs, miR-342-5p showed upregulated expression as Notch signaling was genetically or pharmaceutically interrupted. Consistently, the promoter of the miR-342-5p host gene, the Ena-vasodilator stimulated phosphoprotein-like (Evl, was negatively regulated by Notch signaling, probably through HES5. Transfection of miR-342-5p promoted the differentiation of neural stem cells (NSCs into intermediate neural progenitors (INPs in vitro and reduced the stemness of NSCs in vivo. Furthermore, miR-342-5p inhibited the differentiation of neural stem/intermediate progenitor cells into astrocytes, likely mediated by targeting GFAP directly. Our results indicated that miR-342-5p could function as a downstream effector of Notch signaling to regulate the differentiation of NSCs into INPs and astrocytes commitment. : In this article, Han and colleagues show that miR-342-5p acts as a downstream effector of Notch signaling in the mouse CNS. Notch signal inhibits miR-342-5p expression by regulating its host gene Evl. And with attenuated Notch signal in NSCs, miR-342-5p is upregulated to promote NSCs transition into INPs, and to inhibit astrocyte commitment by targeting GFAP. Keywords: neural stem cells, intermediate neural progenitors, Notch, RBP-J, neuron, glia, miR-342-5p

  9. Increased periodontal bone loss in temporarily B lymphocyte-deficient rats

    DEFF Research Database (Denmark)

    Klausen, B; Hougen, H P; Fiehn, N E

    1989-01-01

    In order to study the role of T lymphocytes and B lymphocytes in the development of marginal periodontitis, experiments were performed on specific-pathogen-free (SPF) rats with various immunologic profiles. The study comprised nude (congenitally T lymphocyte-deficient), thymus-grafted nude (T-lym......-lymphocyte deficiency did not interfere with the development of periodontal disease in this model, whereas a temporary and moderate reduction in B-lymphocyte numbers seemed to predispose for aggravation of periodontal bone loss.......In order to study the role of T lymphocytes and B lymphocytes in the development of marginal periodontitis, experiments were performed on specific-pathogen-free (SPF) rats with various immunologic profiles. The study comprised nude (congenitally T lymphocyte-deficient), thymus-grafted nude (T...... had significantly less periodontal bone support than controls. Anti-mu treated inoculated rats had significantly less periodontal bone support than nude and normal rats, whereas no difference was found between normal, nude, and thymus-grafted rats. It is concluded that permanent T...

  10. The cysteine rich necrotrophic effector SnTox1 produced by Stagonospora nodorum triggers susceptibility of wheat lines harboring Snn1.

    Directory of Open Access Journals (Sweden)

    Zhaohui Liu

    2012-01-01

    Full Text Available The wheat pathogen Stagonospora nodorum produces multiple necrotrophic effectors (also called host-selective toxins that promote disease by interacting with corresponding host sensitivity gene products. SnTox1 was the first necrotrophic effector identified in S. nodorum, and was shown to induce necrosis on wheat lines carrying Snn1. Here, we report the molecular cloning and validation of SnTox1 as well as the preliminary characterization of the mechanism underlying the SnTox1-Snn1 interaction which leads to susceptibility. SnTox1 was identified using bioinformatics tools and verified by heterologous expression in Pichia pastoris. SnTox1 encodes a 117 amino acid protein with the first 17 amino acids predicted as a signal peptide, and strikingly, the mature protein contains 16 cysteine residues, a common feature for some avirulence effectors. The transformation of SnTox1 into an avirulent S. nodorum isolate was sufficient to make the strain pathogenic. Additionally, the deletion of SnTox1 in virulent isolates rendered the SnTox1 mutated strains avirulent on the Snn1 differential wheat line. SnTox1 was present in 85% of a global collection of S. nodorum isolates. We identified a total of 11 protein isoforms and found evidence for strong diversifying selection operating on SnTox1. The SnTox1-Snn1 interaction results in an oxidative burst, DNA laddering, and pathogenesis related (PR gene expression, all hallmarks of a defense response. In the absence of light, the development of SnTox1-induced necrosis and disease symptoms were completely blocked. By comparing the infection processes of a GFP-tagged avirulent isolate and the same isolate transformed with SnTox1, we conclude that SnTox1 may play a critical role during fungal penetration. This research further demonstrates that necrotrophic fungal pathogens utilize small effector proteins to exploit plant resistance pathways for their colonization, which provides important insights into the molecular

  11. Enhanced Effector Function of CD8+ T Cells From Healthy Controls and HIV-Infected Patients Occurs Through Thrombin Activation of Protease-Activated Receptor 1

    Science.gov (United States)

    Hurley, Amanda; Smith, Mindy; Karpova, Tatiana; Hasley, Rebecca B.; Belkina, Natalya; Shaw, Stephen; Balenga, Nariman; Druey, Kirk M.; Nickel, Erin; Packard, Beverly; Imamichi, Hiromi; Hu, Zonghui; Follmann, Dean; McNally, James; Higgins, Jeanette; Sneller, Michael; Lane, H. Clifford; Catalfamo, Marta

    2013-01-01

    Disruption of vascular integrity by trauma and other tissue insults leads to inflammation and activation of the coagulation cascade. The serine protease thrombin links these 2 processes. The proinflammatory function of thrombin is mediated by activation of protease-activated receptor 1 (PAR-1). We found that peripheral blood effector memory CD4+ and CD8+ T lymphocytes expressed PAR-1 and that expression was increased in CD8+ T cells from human immunodeficiency virus (HIV)–infected patients. Thrombin enhanced cytokine secretion in CD8+ T cells from healthy controls and HIV-infected patients. In addition, thrombin induced chemokinesis, but not chemotaxis, of CD8+ T cells, which led to structural changes, including cell polarization and formation of a structure rich in F-actin and phosphorylated ezrin-radexin-moesin proteins. These findings suggest that thrombin mediates cross-talk between the coagulation system and the adaptive immune system at sites of vascular injury through increased T-cell motility and production of proinflammatory cytokines. PMID:23204166

  12. Enhanced effector function of CD8(+) T cells from healthy controls and HIV-infected patients occurs through thrombin activation of protease-activated receptor 1.

    Science.gov (United States)

    Hurley, Amanda; Smith, Mindy; Karpova, Tatiana; Hasley, Rebecca B; Belkina, Natalya; Shaw, Stephen; Balenga, Nariman; Druey, Kirk M; Nickel, Erin; Packard, Beverly; Imamichi, Hiromi; Hu, Zonghui; Follmann, Dean; McNally, James; Higgins, Jeanette; Sneller, Michael; Lane, H Clifford; Catalfamo, Marta

    2013-02-15

    Disruption of vascular integrity by trauma and other tissue insults leads to inflammation and activation of the coagulation cascade. The serine protease thrombin links these 2 processes. The proinflammatory function of thrombin is mediated by activation of protease-activated receptor 1 (PAR-1). We found that peripheral blood effector memory CD4(+) and CD8(+) T lymphocytes expressed PAR-1 and that expression was increased in CD8(+) T cells from human immunodeficiency virus (HIV)-infected patients. Thrombin enhanced cytokine secretion in CD8(+) T cells from healthy controls and HIV-infected patients. In addition, thrombin induced chemokinesis, but not chemotaxis, of CD8(+) T cells, which led to structural changes, including cell polarization and formation of a structure rich in F-actin and phosphorylated ezrin-radexin-moesin proteins. These findings suggest that thrombin mediates cross-talk between the coagulation system and the adaptive immune system at sites of vascular injury through increased T-cell motility and production of proinflammatory cytokines.

  13. [Immunological mechanisms of graft versus tumor effect].

    Science.gov (United States)

    Ine, Shoji; Yamada, Minami; Miyamura, Koichi; Sasaki, Takeshi

    2003-09-01

    Lesson from hematopoietic stem cell transplantation demonstrated that donor immuno-surveillance system can eradicate tumor cells. This is so-call graft versus tumor(GVT) effect. Antigen presenting cells show peptide from minor antigen rather leukemic specific antigen in the context of major histocompatibility complex. The effector cells composed of CD8 T lymphocyte, CD4 T lymphocyte, natural killer cell and natural killer T cell. Death signal was transmitted from effector cells via granzyme/perforin system and FasL/Fas system, and recently TRAIL system seems most important for GVT effect.

  14. Transient exposure to proteins SOX2, Oct-4, and NANOG immortalizes exhausted tumor-infiltrating CTLs

    Energy Technology Data Exchange (ETDEWEB)

    Bhadurihauck, Anjuli; Li, Lei [Department of Animal and Avian Sciences, University of Maryland, College Park, 20742, MD (United States); Li, Qianqian; Wang, Jianjun [Department of Biochemistry and Molecular Biology, Wayne State University, Detroit, 48201 (United States); Xiao, Zhengguo, E-mail: xiao0028@umd.edu [Department of Animal and Avian Sciences, University of Maryland, College Park, 20742, MD (United States)

    2016-05-13

    Adoptive cell transfer therapy (ACT) is one of the most promising immunotherapies against cancer, using tumor-infiltrating lymphocytes (TILs) expanded in vitro. Tumor-infiltrating cytotoxic T lymphocytes (TICTLs) play a prominent role in cancer control. TILs terminally differentiate in response to immunosuppressive environments within tumors, and thus are slow to expand and challenging to maintain both in vitro and in patients. To reverse this exhaustion, we utilize a nuclear protein delivery system that exposes TICTLs to the SOX2, Oct-4, and NANOG (SON) proteins. Unlike activated naïve CTLs (effector CTLs), TICTLs respond favorably to SON treatment, exhibiting steady proliferation and extended survivability independent of cytokine and antigen stimulation. Though TICTLs treated with SON (STICTLs) still express T cell receptors as well as other critical downstream components, they are unresponsive to antigen challenge, suggesting that SON treatment regresses TICTLs into a state similar to that of an early double negative T cell. Our findings indicate the TICTL response to SON proteins is unique when compared to effector CTLs, suggesting TICTLs may be sensitive to regulation by other lineage-specific transcription factors and opening a promising new avenue into cancer immunotherapy. To our knowledge, this is the first report on lineage reprogramming of TILs using protein stem cell transcription factors delivered directly to the nucleus. -- Highlights: •TICTLs are sensitive to reprogramming by proteins of stem cell transcription factors, but effector CTLs were not. •TICTLs are regressed back to an early double negative T cell stage. •TCR signaling is deregulated by these transcription factors.

  15. CXCR3 Directs Antigen-Specific Effector CD4+ T Cell Migration to the Lung During Parainfluenza Virus Infection

    DEFF Research Database (Denmark)

    Kohlmeier, Jacob E; Cookenham, Tres; Miller, Shannon C

    2009-01-01

    effector CD4(+) T cell migration to the lungs. To assess the role of CCR5 and CXCR3 in vivo, we directly compared the migration of Ag-specific wild-type and chemokine receptor-deficient effector T cells in mixed bone marrow chimeric mice during a parainfluenza virus infection. CXCR3-deficient effector CD4......(+) T cells were 5- to 10-fold less efficient at migrating to the lung compared with wild-type cells, whereas CCR5-deficient effector T cells were not impaired in their migration to the lung. In contrast to its role in trafficking, CXCR3 had no impact on effector CD4(+) T cell proliferation, phenotype......, or function in any of the tissues examined. These findings demonstrate that CXCR3 controls virus-specific effector CD4(+) T cell migration in vivo, and suggest that blocking CXCR3-mediated recruitment may limit T cell-induced immunopathology during respiratory virus infections....

  16. Role of interferon in lymphocyte recruitment into the skin

    International Nuclear Information System (INIS)

    Issekutz, T.B.; Stoltz, J.M.; Webster, D.M.

    1986-01-01

    Large numbers of lymphocytes are recruited from the blood into sites of cutaneous DTH reactions. Our goal was to investigate the factors controlling this recruitment. 111 In-labeled peritoneal exudate lymphocytes were injected iv and the accumulation of these cells in skin sites injected with a variety of stimuli, was used to measure lymphocyte recruitment in rats. Large numbers of lymphocytes migrated into vaccinia- and KLH-injected sites in sensitized animals, but only into the viral and not the KLH lesions in non-immune animals. Lymphocytes also migrated efficiently into sites injected with the alpha-interferon (IFN) inducers, uv-inactivated vaccinia virus and poly I:C, as well as into sites injected with IFN. In each case there was a dose-response relationship. Analysis of the kinetics of lymphocyte recruitment demonstrated that the peak rate of migration occurred most rapidly after the injection of IFN, later after poly I:C, and was slowest to be reached after vaccinia virus. Rabbit anti-IFN blocked the recruitment of lymphocytes by uv-inactivated vaccinia and by IFN. Histologically, all of these sites demonstrated a dense mononuclear cell infiltrate in the dermis. It is suggested that IFN may be an important mediator in the recruitment of lymphocytes into inflammatory reactions

  17. T- and NK-cell populations with regulatory phenotype and markers of apoptosis in circulating lymphocytes of patients with CIN3 or microcarcinoma of the cervix: evidence for potential mechanisms of immune suppression.

    Science.gov (United States)

    Kurmyshkina, Olga V; Kovchur, Pavel I; Schegoleva, Ludmila V; Volkova, Tatyana O

    2017-01-01

    Processes and mechanisms responsible for systemic immune suppression in early-stage cervical cancer remain substantially underinvestigated. In this work, we focused on studying the frequencies of circulating regulatory T (CD4 and CD8 Tregs) and NK (NKregs) cells in parallel with assessment of apoptotic markers expression in T cells from patients with preinvasive and microinvasive cervical cancer, with the aim to determine whether up-regulation of apoptosis-associated markers in Т lymphocytes accompanies cervical cancer development and correlates with the change in percentages of regulatory cell populations at systemic level during the initial stages of invasive cervical cancer progression. Fourty two women with histologically confirmed cervical intraepithelial neoplasia grade 3 (CIN3, including carcinoma in situ) or cervical cancer (stage IA) and 30 healthy women (control) were enrolled in the study. Peripheral blood samples were taken immediately before surgery or any treatment and immediately subjected to multicolor flow cytometry. Analysis of a combination of CD4/CD8, CD25, CD127, and FoxP3 markers revealed a statistically significant increase in the frequencies of Tregs within both the CD4 and CD8 subsets of circulating lymphocytes in patients with CIN3 and stage IA cancer. In contrast, lower numbers of NKregs (defined as CD16 dim/neg CD56 bright subpopulation) and increased CD56 dim /CD56 bright NK ratio were found in patients compared to controls, with the percentage of CD16 bright CD56 dim cells (major subtype of circulating NKs) showing no difference. Patients also exhibited an increased expression of CD95 in total peripheral blood T lymphocytes, along with increased level of Annexin V binding to CD95-positive cells, suggesting higher susceptibility of T cells to apoptosis and potential involvement of CD95-dependent pathway in early-stage cervical cancer. Differential analysis of CD4 and CD8 T cells revealed different trends in the change of CD95

  18. Lymphocyte receptors for pertussis toxin

    Energy Technology Data Exchange (ETDEWEB)

    Clark, C.G.; Armstrong, G.D. (Univ. of Alberta, Edmonton (Canada))

    1990-12-01

    We have investigated human T-lymphocyte receptors for pertussis toxin by affinity isolation and photoaffinity labeling procedures. T lymphocytes were obtained from peripheral human blood, surface iodinated, and solubilized in Triton X-100. The iodinated mixture was then passed through pertussis toxin-agarose, and the fractions were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Autoradiography of the fixed, dried gels revealed several bands in the pertussis toxin-bound fraction that were not observed in fractions obtained from histone or fetuin-agarose. Further investigations employed a photoaffinity labeling reagent, sulfosuccinimidyl 2-(p-azido-salicylamido)-1,3'-dithiopropionate, to identify pertussis toxin receptors in freshly isolated peripheral blood monocytic cells, T lymphocytes, and Jurkat cells. In all three cell systems, the pertussis toxin affinity probe specifically labeled a single protein species with an apparent molecular weight of 70,000 that was not observed when the procedure was performed in the presence of excess unmodified pertussis toxin. A protein comparable in molecular weight to the one detected by the photoaffinity labeling technique was also observed among the species that bound to pertussis toxin-agarose. The results suggest that pertussis toxin may bind to a 70,000-Da receptor in human T lymphocytes.

  19. IgG-Fc-mediated effector functions: molecular definition of interaction sites for effector ligands and the role of glycosylation.

    Science.gov (United States)

    Jefferis, R; Lund, J; Pound, J D

    1998-06-01

    The Fc region of human IgG expresses interaction sites for many effector ligands. In this review the topographical distributions of ten of these sites are discussed in relation to functional requirement. It is apparent that interaction sites localised to the inter-CH2-CH3 domain region of the Fc allow for functional divalency, whereas sites localised to the hinge proximal region of the CH2 domain are functionally monovalent, with expression of the latter sites being particularly dependent on glycosylation. All x-ray crystal structures for Fc and Fc-ligand complexes report that the protein structure of the hinge proximal region of the CH2 domain is "disordered", suggesting "internal mobility". We propose a model in which such "internal mobility" results in the generation of a dynamic equilibrium between multiple conformers, certain of which express interaction sites specific to individual ligands. The emerging understanding of the influence of oligosaccharide/protein interactions on protein conformation and biological function of IgG antibodies suggests a potential to generate novel glycoforms of antibody molecules having unique profiles of effector functions.

  20. DMPD: MyDths and un-TOLLed truths: sensor, instructive and effector immunity totuberculosis. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 18191460 MyDths and un-TOLLed truths: sensor, instructive and effector immunity totuberculosis...g) (.svg) (.html) (.csml) Show MyDths and un-TOLLed truths: sensor, instructive and effector immunity totuberculosis...e and effector immunity totuberculosis. Authors Reiling N, Ehlers S, Holscher C. Publication Immunol Lett. 2

  1. Predicting the biodistribution of radiolabeled cMORF effector in MORF-pretargeted mice

    International Nuclear Information System (INIS)

    Liu, Guozheng; Dou, Shuping; He, Jiang; Liu, Xinrong; Rusckowski, Mary; Hnatowich, Donald J.

    2007-01-01

    Pretargeting with phosphorodiamidate morpholino oligomers (MORFs) involves administration of a MORF-conjugated anti-tumor antibody such as MN14 as a pretargeting agent before that of the radiolabeled complementary MORF (cMORF) as the effector. The dosages of the pretargeting agent and effector, the pretargeting interval, and the detection time are the four pretargeting variables. The goal of this study was to develop a semiempirical description capable of predicting the biodistribution of the radiolabeled effector in pretargeted mice and then to compare predictions with experimental results from pretargeting studies in tumored animals in which the pretargeting interval and the detection time were both fixed but the dosages of both the effector and the pretargeting agent were separately varied. Pretargeting studies in LS174T tumored mice were performed using the anti-CEA antibody MN14 conjugated with MORF and the cMORF radiolabeled with 99m Tc. A description was developed based on our previous observations in the same mouse model of the blood and tumor levels of MORF-MN14, accessibility of MORF-MN14 to labeled cMORF, the tumor accumulation of labeled cMORF relative to MORF-MN14 levels therein, and the kidney accumulation of labeled cMORF. The predicted values were then compared with the experimental values. The predicted biodistribution of the radiolabeled effector and the experimental data were in gratifying agreement in normal organs, suggesting that the description of the pretargeting process was reliable. The tumor accumulations occasionally fell outside two standard deviations of that predicted, but after tumor size correction, good agreement between predicted and experimental values was observed here as well. A semiempirical description of the biodistribution of labeled cMORF was capable of predicting the biodistribution of the radiolabeled effector in the pretargeted tumored mouse model, demonstrating that the underlying pretargeting concepts are correct. We

  2. CXCL10 is the key ligand for CXCR3 on CD8+ effector T cells involved in immune surveillance of the lymphocytic choriomeningitis virus-infected central nervous system

    DEFF Research Database (Denmark)

    Christensen, Jeanette Erbo; de Lemos, Carina; Moos, Torben

    2006-01-01

    /ligand pair is thought to play a central role in regulating T cell-mediated inflammation in this organ site. In this report, we investigated the role of CXCL10 in regulating CD8(+) T cell-mediated inflammation in the virus-infected brain. This was done through analysis of CXCL10-deficient mice infected...... indicate a central role for CXCL10 in regulating the accumulation of effector T cells at sites of CNS inflammation, with no apparent compensatory effect of other CXCR3 ligands....

  3. Commensal oral bacteria antigens prime human dendritic cells to induce Th1, Th2 or Treg differentiation.

    Science.gov (United States)

    Kopitar, A N; Ihan Hren, N; Ihan, A

    2006-02-01

    In various immunopathologic conditions, bacterial flora induce an immune response which results in inflammatory manifestations, e.g. periapical granuloma. Dendritic cells provide the main orchestration of specific immune responses. The aim of our study was to test the capacity of distinct oral bacterial antigens (prepared from Streptococcus mitis, Propionibacterium acnes, and Bacteroides spp.) to prime human dendritic cells for stimulation of the T-lymphocyte response. To assess the T-lymphocyte response, the expression of CD25, CD69, intracellular interferon gamma (cIFN-gamma), and intracellular interleukin 4 (cIL-4) was determined. Dendritic cells were prepared from leukocyte buffy coat from healthy blood donors. Monocytes were stimulated with IL-4 and GM-CSF and dendritic cells activated with bacterial lysates. Cell suspensions contained up to 90% dendritic cells, which represented 2-12% of the initial number of mononuclear cells. Lymphocyte subsets that developed in lymphocyte cultures after 1 week of stimulation were analyzed by flow cytometry. Dendritic cells, primed with antigens of Bacteroides fragilis have shown significantly higher activation and expression of intercellular IFN-gamma by T lymphocytes compared to negative controls. The dendritic cells primed with antigens of P. acnes had no effect on T-lymphocyte activation or cytokine production; instead they induced differentiation of T lymphocytes into CD25bright cells (regulatory T cells) with a potentially inhibitory effect on immune response. Dendritic cells primed with antigens of S. mitis induced increased expression of cIL-4. We conclude that commensal oral bacteria antigens prepared from B. fragilis, S. mitis, and P. acnes prime human dendritic cells to induce Th1, Th2, and T(reg) differentiation, respectively. This may advance our understanding of immunopathologic manifestations in the oral cavity and offer new possibilities for redirecting immune responses in mucosal vaccination.

  4. Effector Gene Suites in Some Soil Isolates of Fusarium oxysporum Are Not Sufficient Predictors of Vascular Wilt in Tomato.

    Science.gov (United States)

    Jelinski, Nicolas A; Broz, Karen; Jonkers, Wilfried; Ma, Li-Jun; Kistler, H Corby

    2017-07-01

    Seventy-four Fusarium oxysporum soil isolates were assayed for known effector genes present in an F. oxysporum f. sp. lycopersici race 3 tomato wilt strain (FOL MN-25) obtained from the same fields in Manatee County, Florida. Based on the presence or absence of these genes, four haplotypes were defined, two of which represented 96% of the surveyed isolates. These two most common effector haplotypes contained either all or none of the assayed race 3 effector genes. We hypothesized that soil isolates with all surveyed effector genes, similar to FOL MN-25, would be pathogenic toward tomato, whereas isolates lacking all effectors would be nonpathogenic. However, inoculation experiments revealed that presence of the effector genes alone was not sufficient to ensure pathogenicity on tomato. Interestingly, a nonpathogenic isolate containing the full suite of unmutated effector genes (FOS 4-4) appears to have undergone a chromosomal rearrangement yet remains vegetatively compatible with FOL MN-25. These observations confirm the highly dynamic nature of the F. oxysporum genome and support the conclusion that pathogenesis among free-living populations of F. oxysporum is a complex process. Therefore, the presence of effector genes alone may not be an accurate predictor of pathogenicity among soil isolates of F. oxysporum.

  5. Phenotypic characterization of lymphocytes in HCV/HIV co-infected patients.

    LENUS (Irish Health Repository)

    Roe, Barbara

    2009-02-01

    While hepatitis C virus (HCV)-specific immune responses are attenuated in HCV\\/HIV co-infected patients compared to those infected with HCV alone, the reasons for this remain unclear. In this study, the proportions of regulatory, naïve, and memory T cells, along with chemokine receptor expression, were measured in co-infected and mono-infected patients to determine if there is an alteration in the phenotypic profile of lymphocytes in these patients. HCV\\/HIV co-infected patients had increased proportions of CD4(+) naïve cells and decreased proportions of CD4(+) effector cells when compared to HCV mono-infected patients. The proportions of CD4(+) Tregs and CD4(+) CXCR3(+) T cells were also significantly lower in co-infected patients. A decrease in CD4(+) Tregs and subsequent loss of immunosuppressive function may contribute to the accelerated progression to liver disease in co-infected individuals. Dysregulation of immune responses following reduction in the proportions of CD4(+) CXCR3(+) Th-1 cells may contribute to the reduced functional capacity of HCV-specific immune responses in co-infected patients. The findings of this study provide new information on the T-cell immunophenotype in HCV\\/HIV co-infected patients when compared to those infected with HCV alone, and may provide insight into why cell-mediated immune responses are diminished during HCV infection.

  6. Immature dendritic cells generated from cryopreserved human monocytes show impaired ability to respond to LPS and to induce allogeneic lymphocyte proliferation.

    Directory of Open Access Journals (Sweden)

    Guilherme Ferreira Silveira

    Full Text Available Dendritic cells play a key role in the immune system, in the sensing of foreign antigens and triggering of an adaptive immune response. Cryopreservation of human monocytes was investigated to understand its effect on differentiation into immature monocyte-derived dendritic cells (imdDCs, the response to inflammatory stimuli and the ability to induce allogeneic lymphocyte proliferation. Cryopreserved (crp-monocytes were able to differentiate into imdDCs, albeit to a lesser extent than freshly (frh-obtained monocytes. Furthermore, crp-imdDCs had lower rates of maturation and cytokine/chemokine secretion in response to LPS than frh-imdDCs. Lower expression of Toll-like receptor 4 (at 24 and 48 h and higher susceptibility to apoptosis in crp-imdDCs than in fresh cells would account for the impaired maturation and cytokine/chemokine secretion observed. A mixed leukocyte reaction showed that lymphocyte proliferation was lower with crp-imdDCs than with frh-imdDCs. These findings suggested that the source of monocytes used to generate human imdDCs could influence the accuracy of results observed in studies of the immune response to pathogens, lymphocyte activation, vaccination and antigen sensing. It is not always possible to work with freshly isolated monocytes but the possible effects of freezing/thawing on the biology and responsiveness of imdDCs should be taken into account.

  7. Lymphocytic, cytokine and transcriptomic profiles in peripheral blood of dogs with atopic dermatitis.

    Science.gov (United States)

    Majewska, Alicja; Gajewska, Małgorzata; Dembele, Kourou; Maciejewski, Henryk; Prostek, Adam; Jank, Michał

    2016-08-23

    Canine atopic dermatitis (cAD) is a common chronic and pruritic skin disease in dogs. The development of cAD involves complex interactions between environmental antigens, genetic predisposition and a number of disparate cell types. The aim of the present study was to perform comprehensive analyses of peripheral blood of AD dogs in relation to healthy subjects in order to determine the changes which would be characteristic for cAD. The number of cells in specific subpopulations of lymphocytes was analyzed by flow cytometry, concentration of chosen pro- and anti-inflammatory cytokines (IL-4, IL-10, IL-13, TNF-α, TGF-β1) was determined by ELISA; and microarray analysis was performed on RNA samples isolated from peripheral blood nuclear cells of AD and healthy dogs. The number of Th cells (CD3(+)CD4(+)) in AD and healthy dogs was similar, whereas the percentage of Tc (CD3(+)CD8(+)) and Treg (CD4(+)CD25(+) Foxp3(+)) cells increased significantly in AD dogs. Increased concentrations of IL-13 and TNF-α, and decreased levels of IL-10 and TGF-β1 was observed in AD dogs. The level of IL-4 was similar in both groups of animals. Results of the microarray experiment revealed differentially expressed genes involved in transcriptional regulation (e.g., transcription factors: SMAD2, RORA) or signal transduction pathways (e.g., VEGF, SHB21, PROC) taking part in T lymphocytes lineages differentiation and cytokines synthesis. Results obtained indicate that CD8(+) T cells, beside CD4(+) T lymphocytes, contribute to the development of the allergic response. Increased IL-13 concentration in AD dogs suggests that this cytokine may play more important role than IL-4 in mediating changes induced by allergic inflammation. Furthermore, observed increase in Treg cells in parallel with high concentrations of TNF-α and low levels of IL-10 and TGF-β1 in the peripheral blood of AD dogs point at the functional insufficiency of Treg cells in patients with AD.

  8. Mechanism of chlorphentermine-induced lymphocyte toxicity: initial investigations

    International Nuclear Information System (INIS)

    Sauers, L.J.; Wierda, D.; Reasor, M.J.

    1986-01-01

    Chlorphentermine (CP) inhibits the blastogenic response of mouse splenic and human peripheral blood lymphocytes to the T-cell mitogens, phytohemagglutinin (PHA) and concanavalin A (Con A). The purpose of these studies was to examine in vitro the mechanism mediating this immunosuppression. If mouse or human lymphocytes are pretreated with CP for 30 minutes, then stimulated with PHA, their blastogenic response is inhibited 80% and 45%, respectively. However, if CP is not added until 10 minutes or later following PHA stimulation, the inhibitory effect of the drug is essentially eliminated. The authors also determined that CP can potentiate Con A-induced agglutination of human lymphocytes. Enhanced agglutination can result from changes in the integrity of membrane phospholipids. Because changes in membrane phospholipid biochemistry characteristically occur within 10 minutes after mitogen-induced lymphocyte activation, the authors examined whether CP altered the incorporation of choline into cellular phospholipids. They found that CP decreases overall incorporation of 14 C-choline into cellular phospholipids of mouse lymphocytes by 45% during the first 4 hours of activation. These data suggest that the immunotoxicity associated with CP may be mediated by drug-induced changes at the membrane level that appear to occur early during lymphocyte activation

  9. Eosinophilia of dystrophin-deficient muscle is promoted by perforin-mediated cytotoxicity by T cell effectors

    Science.gov (United States)

    Cai, B.; Spencer, M. J.; Nakamura, G.; Tseng-Ong, L.; Tidball, J. G.

    2000-01-01

    Previous investigations have shown that cytotoxic T lymphocytes (CTLs) contribute to muscle pathology in the dystrophin-null mutant mouse (mdx) model of Duchenne muscular dystrophy through perforin-dependent and perforin-independent mechanisms. We have assessed whether the CTL-mediated pathology includes the promotion of eosinophilia in dystrophic muscle, and thereby provides a secondary mechanism through which CTLs contribute to muscular dystrophy. Quantitative immunohistochemistry confirmed that eosinophilia is a component of the mdx dystrophy. In addition, electron microscopic observations show that eosinophils traverse the basement membrane of mdx muscle fibers and display sites of close apposition of eosinophil and muscle membranes. The close membrane apposition is characterized by impingement of eosinophilic rods of major basic protein into the muscle cell membrane. Transfer of mdx splenocytes and mdx muscle extracts to irradiated C57 mice by intraperitoneal injection resulted in muscle eosinophilia in the recipient mice. Double-mutant mice lacking dystrophin and perforin showed less eosinophilia than was displayed by mdx mice that expressed perforin. Finally, administration of prednisolone, which has been shown previously to reduce the concentration of CTLs in dystrophic muscle, produced a significant reduction in eosinophilia. These findings indicate that eosinophilia is a component of the mdx pathology that is promoted by perforin-dependent cytotoxicity of effector T cells. However, some eosinophilia of mdx muscle is independent of perforin-mediated processes.

  10. Mechanism of host substrate acetylation by a YopJ family effector.

    Science.gov (United States)

    Zhang, Zhi-Min; Ma, Ka-Wai; Gao, Linfeng; Hu, Zhenquan; Schwizer, Simon; Ma, Wenbo; Song, Jikui

    2017-07-24

    The Yersinia outer protein J (YopJ) family of bacterial effectors depends on a novel acetyltransferase domain to acetylate signalling proteins from plant and animal hosts. However, the underlying mechanism is unclear. Here, we report the crystal structures of PopP2, a YopJ effector produced by the plant pathogen Ralstonia solanacearum, in complex with inositol hexaphosphate (InsP 6 ), acetyl-coenzyme A (AcCoA) and/or substrate Resistance to Ralstonia solanacearum 1 (RRS1-R) WRKY . PopP2 recognizes the WRKYGQK motif of RRS1-R WRKY to position a targeted lysine in the active site for acetylation. Importantly, the PopP2-RRS1-R WRKY association is allosterically regulated by InsP 6 binding, suggesting a previously unidentified role of the eukaryote-specific cofactor in substrate interaction. Furthermore, we provide evidence for the reaction intermediate of PopP2-mediated acetylation, an acetyl-cysteine covalent adduct, lending direct support to the 'ping-pong'-like catalytic mechanism proposed for YopJ effectors. Our study provides critical mechanistic insights into the virulence activity of YopJ class of acetyltransferases.

  11. Antibody-mediated suppression of grafted lymphoma. III. Evaluation of the role of thymic function, non-thymus-derived lymphocytes, macrophages, platelets, and polymorphonuclear leukocytes in syngeneic and allogeneic hosts

    International Nuclear Information System (INIS)

    Shin, H.S.; Hayden, M.; Langley, S.; Kaliss, N.; Smith, M.R.

    1975-01-01

    Syngeneic or allogeneic mice pretreated with sublethal whole-body irradiation were rendered incapable of suppressing the growth of grafted tumor cells sensitized with alloantibody. The growth of sensitized tumor cells was suppressed when they were mixed with donor effector cells from mice syngeneic or allogeneic to the recipients and then were inoculated in irradiated recipients. Three donor-host combinations were used to study the suppression of the murine lymphoma 6C3HED indigenous to C3H mice. These were C3H donor cells in C3H recipients, C57BL/6 donor cells in C3H recipients, or C57BL/6 donor cells in C57BL/6 recipients. In all three combinations, macrophages obtained from an inflammatory exudate, exudate lymphocytes not bearing theta antigen, and platelets were, in descending order of effectiveness, consistently active in restoring antibody-mediated suppression of tumor growth in irradiated hosts. Prior irradiation of the transferred lymphocytes somewhat diminished their effectiveness. Freeze-thawed or heat-killed macrophages (but not freeze-thawed platelets or lymphocytes) were effective in restoration. Peripheral blood mononuclear leukocytes and splenic lymphoid cells were not active in the recipients syngeneic to the donor cells but were active in recipients allogeneic to the donor cells. Polymorphonuclear leukocytes isolated from peripheral blood or an inflammatory exudate were not active. Intact thymic function seems unimportant since antibody-mediated suppression took place as effectively in thymectomized mice as in normal controls. (U.S.)

  12. Bio-effectors from waste materials as growth promoters for tomato plants, an agronomic and metabolomic study

    Science.gov (United States)

    Abou Chehade, Lara; Chami, Ziad Al; De Pascali, Sandra; Cavoski, Ivana; Fanizzi, Francesco Paolo

    2015-04-01

    In organic farming, where nutrient management is constrained and sustainability is claimed, bio-effectors pave their way. Considering selected bio-effectors, this study integrates metabolomics to agronomy in depicting induced relevant phenomena. Extracts of three agro-industrial wastes (Lemon processing residues, Fennel processing residues and Brewer's spent grain) are being investigated as sources of bio-effectors for the third trial consequently. Corresponding individual and mixture aqueous extracts are assessed for their synergistic and/or single agronomic and qualitative performances on soil-grown tomato, compared to both a control and humic acid treatments. A metabolomic profiling of tomato fruits via the Proton Nuclear Magnetic Resonance (NMR) spectroscopy, as holistic indicator of fruit quality and extract-induced responses, complements crop productivity and organoleptic/nutritional qualitative analyses. Results are expected to show mainly an enhancement of the fruit qualitative traits, and to confirm partly the previous results of better crop productivity and metabolism enhancement. Waste-derived bio-effectors could be, accordingly, demonstrated as potential candidates of plant-enhancing substances. Keywords: bio-effectors, organic farming, agro-industrial wastes, nuclear magnetic resonance (NMR), tomato.

  13. Chronic lymphocytic leukemia: concepts and observations

    Energy Technology Data Exchange (ETDEWEB)

    Chandra, P.; Chanana, A.D.; Chikkappa, G.; Cronkite, E.P.

    1977-01-01

    Thirty-five patients with chronic lymphocytic leukemia (CLL) were studied for assessment of total body leukemic mass and abnormality in T-lymphocyte function associated with clinical stages of CLL. Total body potassium (TBK), an indicator of lean body mass, was found to correlate well with increase in the clinical stage of the disease. Use of TBK for monitoring the regression and relapse of leukemic load is suggested. No correlation was found between whole cell and nuclear volumes of lymphocytes in CLL patients and clinical stages of the disease. Blast transformation and proliferation under phytohemagglutinin (PHA) stimulation appeared to be normal in purified T cells of early stages and abnormal in the late stages of disease.

  14. [Occurrence of associated tumours in chronic lymphocytic leukemia].

    Science.gov (United States)

    Szerafin, László; Jakó, János; Varju, Lóránt

    2016-10-01

    Chronic lymphocytic leukemia is one of the most common hematologic malignancy. The aim of the authors was to investigate the characteristics of malignancies associated with chronic lymphocytic leukemia in patients diagnozed between 2000 and 2015. Data of patients with chronic lymphocytic leukemia who had other associated tumours were analysed using the Leukemia/Lymphoma Registry of the Szabolcs-Szatmár-Bereg County, Hungary and patient records. Between January 1, 2000 and December 31, 2015, 526 patients with chronic lymphocytic leukemia were diagnosed. 95 patients of the 526 patients (18.06%) were diagnosed as having associated other tumours. In 48/95 patients (50.5%) the first diagnosed tumour was chronic lymphocytic leukemia, in 23/95 patients (24.2%) the first recognized malignancy was the associated tumour, whereas in 24/95 patients (25.3%) synchron tumours were diagnosed. The number of patients with more than one associated tumour was 10/95 (10.5%). The total number of tumours was 107. The incidence of chronic lymphoid leukemia increased in the period between 2000 and 2015 as compared to the period between 1983 and 1999 (3.19 vs 5.65/100 000 person/year). The occurrence of associated malignancies increased as well (8.06% vs 18.06%). In addition to the most common tumours (colorectal, breast, lung, prostate), skin squamous cell carcinoma (17/95 patients; 17.9%) and melanoma (6/95 patients; 6.3%) also frequently occurred. The second malignancies were most frequently discovered after the diagnosis of chronic lymphocytic leukemia and synchron tumours accounting for 78.5% (84/107) of all associated tumours. The incidence of second malignancies decreased 10 years after the diagnosis of chronic lymphocytic leukemia. The possible reasons for the high frequency of other tumours associated with chronic lymphocytic leukemia are elderly age of patients, immunsuppressed state and, presumably, chemotherapy of patients with chronic lymphocytic leukemia. During the follow up

  15. Lymphocyte-Related Inflammation and Immune-Based Scores Predict Prognosis of Chordoma Patients After Radical Resection

    Directory of Open Access Journals (Sweden)

    Wenhao Hu

    2018-04-01

    Full Text Available The inflammatory microenvironment plays a critical role in the development and progression of malignancies. In the present study, we aimed to evaluate the prognostic value of lymphocyte-related inflammation and immune-based prognostic scores in patients with chordoma after radical resection, including the neutrophil-lymphocyte ratio (NLR, platelet-lymphocyte ratio (PLR, monocyte-lymphocyte ratio (MLR, and systemic immune-inflammation index (SII. A total of 172 consecutive patients with chordoma who underwent radical resection were reviewed. R software was used to randomly select 86 chordoma patients as a training set and 86 chordoma patients as a validation set. Potential prognostic factors were also identified, including age, sex, tumor localization, KPS, Enneking stage, tumor size, and tumor metastasis. Overall survival (OS was calculated using the Kaplan–Meier method and multivariate Cox regression analyses. NLR, PLR, SII, Enneking stage, tumor differentiation and tumor metastasis were identified as significant factors from the univariate analysis in both the training and validation sets and were subjected to multivariate Cox proportional hazards analysis. The univariate analysis showed that NLR ≥1.65, PLR ≥121, and SII ≥370×109/L were significantly associated with poor OS. In the multivariate Cox proportional hazard analysis, SII, Enneking stage and tumor metastasis were significantly associated with OS. As noninvasive, low-cost, reproducible prognostic biomarkers, NLR, PLR and SII could help predict poor prognosis in patients with chordoma after radical resection. This finding may contribute to the development of more effective tailored therapy according to the characteristics of individual tumors.

  16. Imbalanced expression of functional surface molecules in regulatory and effector T cells in systemic lupus erythematosus

    International Nuclear Information System (INIS)

    Mesquita Júnior, D.; Cruvinel, W.M.; Araujo, J.A.P.; Salmazi, K.C.; Kallas, E.G.; Andrade, L.E.C.

    2014-01-01

    Regulatory T (TREG) cells play an important role in maintaining immune tolerance and avoiding autoimmunity. We analyzed the expression of membrane molecules in TREG and effector T cells in systemic lupus erythematosus (SLE). TREG and effector T cells were analyzed for the expression of CTLA-4, PD1, CD28, CD95, GITR, HLA-DR, OX40, CD40L, and CD45RO in 26 patients with active disease, 31 with inactive disease, and 26 healthy controls. TREG cells were defined as CD25 +/high CD127 Ø/low FoxP3 + , and effector T cells were defined as CD25 + CD127 + FoxP3 Ø . The ratio of TREG to effector T cells expressing GITR, PD1, HLA-DR, OX40, CD40L, and CD45RO was determined in the three groups. The frequency of TREG cells was similar in patients with SLE and controls. However, SLE patients had a decreased frequency of CTLA-4 + TREG and CD28 + TREG cells and an increased frequency of CD40L + TREG cells. There was a decrease in the TREG/effector-T ratio for GITR + , HLA-DR + , OX40 + , and CD45RO + cells, and an increased ratio of TREG/effector-T CD40L + cells in patients with SLE. In addition, CD40L + TREG cell frequency correlated with the SLE disease activity index (P=0.0163). In conclusion, our findings showed several abnormalities in the expression of functionally critical surface molecules in TREG and effector T cells in SLE that may be relevant to the pathogenesis of this disease

  17. Imbalanced expression of functional surface molecules in regulatory and effector T cells in systemic lupus erythematosus

    Energy Technology Data Exchange (ETDEWEB)

    Mesquita Júnior, D. [Disciplina de Reumatologia, Departamento de Medicina, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil); Cruvinel, W.M. [Disciplina de Reumatologia, Departamento de Medicina, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil); Departamento de Biomedicina, Universidade Católica de Goiás, Goiânia, GO (Brazil); Araujo, J.A.P. [Disciplina de Reumatologia, Departamento de Medicina, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil); Salmazi, K.C.; Kallas, E.G. [Disciplina de Imunologia Clínica e Alergia, Departamento de Clínica Médica, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Andrade, L.E.C. [Disciplina de Reumatologia, Departamento de Medicina, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil)

    2014-08-22

    Regulatory T (TREG) cells play an important role in maintaining immune tolerance and avoiding autoimmunity. We analyzed the expression of membrane molecules in TREG and effector T cells in systemic lupus erythematosus (SLE). TREG and effector T cells were analyzed for the expression of CTLA-4, PD1, CD28, CD95, GITR, HLA-DR, OX40, CD40L, and CD45RO in 26 patients with active disease, 31 with inactive disease, and 26 healthy controls. TREG cells were defined as CD25{sup +/high}CD127{sup Ø/low}FoxP3{sup +}, and effector T cells were defined as CD25{sup +}CD127{sup +}FoxP3{sup Ø}. The ratio of TREG to effector T cells expressing GITR, PD1, HLA-DR, OX40, CD40L, and CD45RO was determined in the three groups. The frequency of TREG cells was similar in patients with SLE and controls. However, SLE patients had a decreased frequency of CTLA-4{sup +}TREG and CD28{sup +}TREG cells and an increased frequency of CD40L{sup +}TREG cells. There was a decrease in the TREG/effector-T ratio for GITR{sup +}, HLA-DR{sup +}, OX40{sup +}, and CD45RO{sup +} cells, and an increased ratio of TREG/effector-T CD40L{sup +} cells in patients with SLE. In addition, CD40L{sup +}TREG cell frequency correlated with the SLE disease activity index (P=0.0163). In conclusion, our findings showed several abnormalities in the expression of functionally critical surface molecules in TREG and effector T cells in SLE that may be relevant to the pathogenesis of this disease.

  18. A generalized quantitative antibody homeostasis model: maintenance of global antibody equilibrium by effector functions.

    Science.gov (United States)

    Prechl, József

    2017-11-01

    The homeostasis of antibodies can be characterized as a balanced production, target-binding and receptor-mediated elimination regulated by an interaction network, which controls B-cell development and selection. Recently, we proposed a quantitative model to describe how the concentration and affinity of interacting partners generates a network. Here we argue that this physical, quantitative approach can be extended for the interpretation of effector functions of antibodies. We define global antibody equilibrium as the zone of molar equivalence of free antibody, free antigen and immune complex concentrations and of dissociation constant of apparent affinity: [Ab]=[Ag]=[AbAg]= K D . This zone corresponds to the biologically relevant K D range of reversible interactions. We show that thermodynamic and kinetic properties of antibody-antigen interactions correlate with immunological functions. The formation of stable, long-lived immune complexes correspond to a decrease of entropy and is a prerequisite for the generation of higher-order complexes. As the energy of formation of complexes increases, we observe a gradual shift from silent clearance to inflammatory reactions. These rules can also be applied to complement activation-related immune effector processes, linking the physicochemical principles of innate and adaptive humoral responses. Affinity of the receptors mediating effector functions shows a wide range of affinities, allowing the continuous sampling of antibody-bound antigen over the complete range of concentrations. The generation of multivalent, multicomponent complexes triggers effector functions by crosslinking these receptors on effector cells with increasing enzymatic degradation potential. Thus, antibody homeostasis is a thermodynamic system with complex network properties, nested into the host organism by proper immunoregulatory and effector pathways. Maintenance of global antibody equilibrium is achieved by innate qualitative signals modulating a

  19. Fructose 1-phosphate is the preferred effector of the metabolic regulator Cra of Pseudomonas putida.

    Science.gov (United States)

    Chavarría, Max; Santiago, César; Platero, Raúl; Krell, Tino; Casasnovas, José M; de Lorenzo, Víctor

    2011-03-18

    The catabolite repressor/activator (Cra) protein is a global sensor and regulator of carbon fluxes through the central metabolic pathways of gram-negative bacteria. To examine the nature of the effector (or effectors) that signal such fluxes to the protein of Pseudomonas putida, the Cra factor of this soil microorganism has been purified and characterized and its three-dimensional structure determined. Analytical ultracentrifugation, gel filtration, and mobility shift assays showed that the effector-free Cra is a dimer that binds an operator DNA sequence in the promoter region of the fruBKA cluster. Furthermore, fructose 1-phosphate (F1P) was found to most efficiently dissociate the Cra-DNA complex. Thermodynamic parameters of the F1P-Cra-DNA interaction calculated by isothermal titration calorimetry revealed that the factor associates tightly to the DNA sequence 5'-TTAAACGTTTCA-3' (K(D) = 26.3 ± 3.1 nM) and that F1P binds the protein with an apparent stoichiometry of 1.06 ± 0.06 molecules per Cra monomer and a K(D) of 209 ± 20 nM. Other possible effectors, like fructose 1,6-bisphosphate, did not display a significant affinity for the regulator under the assay conditions. Moreover, the structure of Cra and its co-crystal with F1P at a 2-Å resolution revealed that F1P fits optimally the geometry of the effector pocket. Our results thus single out F1P as the preferred metabolic effector of the Cra protein of P. putida.

  20. Fructose 1-Phosphate Is the Preferred Effector of the Metabolic Regulator Cra of Pseudomonas putida*

    Science.gov (United States)

    Chavarría, Max; Santiago, César; Platero, Raúl; Krell, Tino; Casasnovas, José M.; de Lorenzo, Víctor

    2011-01-01

    The catabolite repressor/activator (Cra) protein is a global sensor and regulator of carbon fluxes through the central metabolic pathways of Gram-negative bacteria. To examine the nature of the effector (or effectors) that signal such fluxes to the protein of Pseudomonas putida, the Cra factor of this soil microorganism has been purified and characterized and its three-dimensional structure determined. Analytical ultracentrifugation, gel filtration, and mobility shift assays showed that the effector-free Cra is a dimer that binds an operator DNA sequence in the promoter region of the fruBKA cluster. Furthermore, fructose 1-phosphate (F1P) was found to most efficiently dissociate the Cra-DNA complex. Thermodynamic parameters of the F1P-Cra-DNA interaction calculated by isothermal titration calorimetry revealed that the factor associates tightly to the DNA sequence 5′-TTAAACGTTTCA-3′ (KD = 26.3 ± 3.1 nm) and that F1P binds the protein with an apparent stoichiometry of 1.06 ± 0.06 molecules per Cra monomer and a KD of 209 ± 20 nm. Other possible effectors, like fructose 1,6-bisphosphate, did not display a significant affinity for the regulator under the assay conditions. Moreover, the structure of Cra and its co-crystal with F1P at a 2-Å resolution revealed that F1P fits optimally the geometry of the effector pocket. Our results thus single out F1P as the preferred metabolic effector of the Cra protein of P. putida. PMID:21239488