7T MRI in focal epilepsy with unrevealing conventional field strength imaging.

Science.gov (United States)

De Ciantis, Alessio; Barba, Carmen; Tassi, Laura; Cosottini, Mirco; Tosetti, Michela; Costagli, Mauro; Bramerio, Manuela; Bartolini, Emanuele; Biagi, Laura; Cossu, Massimo; Pelliccia, Veronica; Symms, Mark R; Guerrini, Renzo

2016-03-01

To assess the diagnostic yield of 7T magnetic resonance imaging (MRI) in detecting and characterizing structural lesions in patients with intractable focal epilepsy and unrevealing conventional (1.5 or 3T) MRI. We conducted an observational clinical imaging study on 21 patients (17 adults and 4 children) with intractable focal epilepsy, exhibiting clinical and electroencephalographic features consistent with a single seizure-onset zone (SOZ) and unrevealing conventional MRI. Patients were enrolled at two tertiary epilepsy surgery centers and imaged at 7T, including whole brain (three-dimensional [3D] T1 -weighted [T1W] fast-spoiled gradient echo (FSPGR), 3D susceptibility-weighted angiography [SWAN], 3D fluid-attenuated inversion recovery [FLAIR]) and targeted imaging (2D T2*-weighted dual-echo gradient-recalled echo [GRE] and 2D gray-white matter tissue border enhancement [TBE] fast spin echo inversion recovery [FSE-IR]). MRI studies at 1.5 or 3T deemed unrevealing at the referral center were reviewed by three experts in epilepsy imaging. Reviewers were provided information regarding the suspected localization of the SOZ. The same team subsequently reviewed 7T images. Agreement in imaging interpretation was reached through consensus-based discussions based on visual identification of structural abnormalities and their likely correlation with clinical and electrographic data. 7T MRI revealed structural lesions in 6 (29%) of 21 patients. The diagnostic gain in detection was obtained using GRE and FLAIR images. Four of the six patients with abnormal 7T underwent epilepsy surgery. Histopathology revealed focal cortical dysplasia (FCD) in all. In the remaining 15 patients (71%), 7T MRI remained unrevealing; 4 of the patients underwent epilepsy surgery and histopathologic evaluation revealed gliosis. 7T MRI improves detection of epileptogenic FCD that is not visible at conventional field strengths. A dedicated protocol including whole brain FLAIR and GRE images at 7T

Controlling T-Cell Activation with Synthetic Dendritic Cells Using the Multivalency Effect

NARCIS (Netherlands)

Hammink, R.; Mandal, S.; Eggermont, L.J.; Nooteboom, M.; Willems, P.H.G.M.; Tel, J.; Rowan, A.E.; Figdor, C.G.; Blank, K.G.

2017-01-01

Artificial antigen-presenting cells (aAPCs) have recently gained a lot of attention. They efficiently activate T cells and serve as powerful replacements for dendritic cells in cancer immunotherapy. Focusing on a specific class of polymer-based aAPCs, so-called synthetic dendritic cells (sDCs), we

Systems considerations in mosaic focal planes

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White, K. P., III

1983-08-01

Two key reasons for pursuing the development of mosaic focal planes are reviewed and it is shown that rapid frame repetition rate is the only requirement that can be solved no other way than through mosaic focal planes. With the view that spaceborne mosaic focal plane sensors are necessarily 'smart sensors' requiring a lot of onboard processing just to function, it is pointed out that various artificial intelligence techniques may be the most appropriate to incorporate in the data processing. Finally, a novel mosaic focal plane design is proposed, termed a virtual mosaic focal plane, in response to other system constraints.

TRIM15 is a focal adhesion protein that regulates focal adhesion disassembly

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Uchil, Pradeep D.; Pawliczek, Tobias; Reynolds, Tracy D.; Ding, Siyuan; Hinz, Angelika; Munro, James B.; Huang, Fang; Floyd, Robert W.; Yang, Haitao; Hamilton, William L.; Bewersdorf, Joerg; Xiong, Yong; Calderwood, David A.; Mothes, Walther

2014-01-01

ABSTRACT Focal adhesions are macromolecular complexes that connect the actin cytoskeleton to the extracellular matrix. Dynamic turnover of focal adhesions is crucial for cell migration. Paxillin is a multi-adaptor protein that plays an important role in regulating focal adhesion dynamics. Here, we identify TRIM15, a member of the tripartite motif protein family, as a paxillin-interacting factor and a component of focal adhesions. TRIM15 localizes to focal contacts in a myosin-II-independent manner by an interaction between its coiled-coil domain and the LD2 motif of paxillin. Unlike other focal adhesion proteins, TRIM15 is a stable focal adhesion component with restricted mobility due to its ability to form oligomers. TRIM15-depleted cells display impaired cell migration and reduced focal adhesion disassembly rates, in addition to enlarged focal adhesions. Thus, our studies demonstrate a cellular function for TRIM15 as a regulatory component of focal adhesion turnover and cell migration. PMID:25015296

Epstein-Barr virus-associated peripheral T-Cell lymphoma involving spleen in a renal transplant patient.

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Lee, Hye Kyung; Kim, Hee Jung; Lee, Eun Hee; Kim, Suk Young; Park, Tae In; Kang, Chang Suk; Yang, Woo Ick

2003-01-01

The incidence of posttransplantation lymphoproliferative disorders (PTLDs) has increased in recent years. Although rare, various types of T-cell lymphoma have been reported and their association with Epstein-Barr virus (EBV) has been compared with B-cell PTLDs. We report a case of splenic peripheral T-cell lymphoma occurring in a 47-yr-old male patient 7 yr after renal allograft transplantation. The spleen showed sinusoidal proliferation of focal CD30 positive, large, atypical lymphoid cells. Positivity for CD3 and cytolytic granule-associated proteins was also demonstrated in the tumor cells, while anaplastic large cell lymphoma kinase (ALK) and CD8 were not expressed. Strong nuclear signals for EBV mRNA were noted by EBER1 in situ hybridization. A molecular genetic study demonstrated a rearrangement of the gamma T-cell receptor gene. To our knowledge, this case is unique in terms of a posttransplant T-cell lymphoma that shows focal CD30, cytolytic granule-associated proteins, and EBV positivity. PMID:12692428

Micro–adhesion rings surrounding TCR microclusters are essential for T cell activation

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Sakuma, Machie; Yokosuka, Tadashi

2016-01-01

The immunological synapse (IS) formed at the interface between T cells and antigen-presenting cells represents a hallmark of initiation of acquired immunity. T cell activation is initiated at T cell receptor (TCR) microclusters (MCs), in which TCRs and signaling molecules assemble at the interface before IS formation. We found that each TCR-MC was transiently bordered by a ring structure made of integrin and focal adhesion molecules in the early phase of activation, which is similar in structure to the IS in microscale. The micro–adhesion ring is composed of LFA-1, focal adhesion molecules paxillin and Pyk2, and myosin II (MyoII) and is supported by F-actin core and MyoII activity through LFA-1 outside-in signals. The formation of the micro–adhesion ring was transient but especially sustained upon weak TCR stimulation to recruit linker for activation of T cells (LAT) and SLP76. Perturbation of the micro–adhesion ring induced impairment of TCR-MC development and resulted in impaired cellular signaling and cell functions. Thus, the synapse-like structure composed of the core TCR-MC and surrounding micro–adhesion ring is a critical structure for initial T cell activation through integrin outside-in signals. PMID:27354546

GLYCAN-DIRECTED CAR-T CELLS.

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Steentoft, Catharina; Migliorini, Denis; King, Tiffany R; Mandel, Ulla; June, Carl H; Posey, Avery D

2018-01-23

Cancer immunotherapy is rapidly advancing in the treatment of a variety of hematopoietic cancers, including pediatric acute lymphoblastic leukemia and diffuse large B cell lymphoma, with chimeric antigen receptor (CAR)-T cells. CARs are genetically encoded artificial T cell receptors that combine the antigen specificity of an antibody with the machinery of T cell activation. However, implementation of CAR technology in the treatment of solid tumors has been progressing much slower. Solid tumors are characterized by a number of challenges that need to be overcome, including cellular heterogeneity, immunosuppressive tumor microenvironment (TME), and, in particular, few known cancer-specific targets. Post-translational modifications that differentially occur in malignant cells generate valid cell surface, cancer-specific targets for CAR-T cells. We previously demonstrated that CAR-T cells targeting an aberrant O-glycosylation of MUC1, a common cancer marker associated with changes in cell adhesion, tumor growth, and poor prognosis, could control malignant growth in mouse models. Here, we discuss the field of glycan-directed CAR-T cells and review the different classes of antibodies specific for glycan-targeting, including the generation of high affinity O-glycopeptide antibodies. Finally, we discuss historic and recently investigated glycan targets for CAR-T cells and provide our perspective on how targeting the tumor glycoproteome and/or glycome will improve CAR-T immunotherapy. © The Author(s) 2018. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The Ratio of Blood T Follicular Regulatory Cells to T Follicular Helper Cells Marks Ectopic Lymphoid Structure Formation While Activated Follicular Helper T Cells Indicate Disease Activity in Primary Sjögren's Syndrome.

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Fonseca, Valter R; Romão, Vasco C; Agua-Doce, Ana; Santos, Mara; López-Presa, Dolores; Ferreira, Ana Cristina; Fonseca, João Eurico; Graca, Luis

2018-05-01

To investigate whether the balance of blood follicular helper T (Tfh) cells and T follicular regulatory (Tfr) cells can provide information about ectopic lymphoid neogenesis and disease activity in primary Sjögren's syndrome (SS). We prospectively recruited 56 patients clinically suspected of having SS. Sixteen of these patients subsequently fulfilled the American-European Consensus Group criteria for SS and were compared to 16 patients with non-SS sicca syndrome. Paired blood and minor salivary gland (MSG) biopsy samples were analyzed to study Tfr cells and subsets of Tfh cells in both compartments. Patients with primary SS had normal Tfh cell counts in peripheral blood; however, activated programmed death 1-positive (PD-1+) inducible costimulator-positive (ICOS+) Tfh cells in peripheral blood were strongly associated with disease activity assessed by the European League Against Rheumatism Sjögren's Syndrome Disease Activity Index (r = 0.8547, P = 0.0008). Conversely, the blood Tfr cell:Tfh cell ratio indicated ectopic lymphoid structure formation in MSGs, being strongly associated with B cell, CD4+ T cell, and PD-1+ICOS+ T cell infiltration in MSGs, and was especially increased in patients with focal sialadenitis. Further analysis showed that the blood Tfr cell:Tfh cell ratio allowed discrimination between SS patients and healthy donors with excellent accuracy and was a strong predictor of SS diagnosis (odds ratio [OR] 12.96, P = 0.028) and the presence of focal sialadenitis (OR 10, P = 0.022) in patients investigated for sicca symptoms, thus highlighting the potential clinical value of this marker. The blood Tfr cell:Tfh cell ratio and PD-1+ICOS+ Tfh cells constitute potential novel biomarkers for different features of primary SS. While the blood Tfr cell:Tfh cell ratio is associated with ectopic lymphoid neogenesis, activated Tfh cells indicate disease activity. © 2018, American College of Rheumatology.

Clonación artificial de controladores basados en técnicas de inteligencia artificial

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Javier Antonio Ballesteros

2004-11-01

Full Text Available En el presente articulo se expone un avance de anteproyecto, sobre técnicas de inteligencia Artificial, su aplicación a procesos industriales y herramientas para realizar simulación. Se citan algunos trabajos en los cuales hay resultados, y que prestan un soporte lógico para continuar con el desarrollo del proyecto. Ademas, se analiza, la función que cumple el controlador el cual debe ser preciso, confiable y que a su vez reduzca costos. Por estas razones se tomó como base del proyecto un controlador que posea estas características para que se puedan aplicar técnicas de lnteligencia Artificial y poder realizar Ia colación artificial.

Spatial focalization of pheromone/MAPK signaling triggers commitment to cell–cell fusion

Science.gov (United States)

Merlini, Laura

2016-01-01

Cell fusion is universal in eukaryotes for fertilization and development, but what signals this process is unknown. Here, we show in Schizosaccharomyces pombe that fusion does not require a dedicated signal but is triggered by spatial focalization of the same pheromone–GPCR (G-protein-coupled receptor)–MAPK signaling cascade that drives earlier mating events. Autocrine cells expressing the receptor for their own pheromone trigger fusion attempts independently of cell–cell contact by concentrating pheromone release at the fusion focus, a dynamic actin aster underlying the secretion of cell wall hydrolases. Pheromone receptor and MAPK cascade are similarly enriched at the fusion focus, concomitant with fusion commitment in wild-type mating pairs. This focalization promotes cell fusion by immobilizing the fusion focus, thus driving local cell wall dissolution. We propose that fusion commitment is imposed by a local increase in MAPK concentration at the fusion focus, driven by a positive feedback between fusion focus formation and focalization of pheromone release and perception. PMID:27798845

Nanoscale spin sensing in artificial cell membranes

International Nuclear Information System (INIS)

Simpson David

2014-01-01

The use of the nitrogen-vacancy (NV) centre in diamond as a single spin sensor or magnetometer has attracted considerable interest in recent years because of its unique combination of sensitivity, nanoscale resolution, and optical initialisation and readout at room temperature. Nanodiamonds in particular hold great promise as an optical magnetometer probe for bio applications. In this work we employ nanodiamonds containing single NV spins to detect freely diffusing Mn2+ ions by detecting changes in the transverse relaxation time (T2) of the single spin probe. We also report the detection of gadolinium spin labels present in an artificial cell membrane by measuring changes in the longitudinal relaxation time (T1) of the probe. (author)

Freeze-thaw lysates of Plasmodium falciparum-infected red blood cells induce differentiation of functionally competent regulatory T cells from memory T cells.

Science.gov (United States)

Finney, Olivia C; Lawrence, Emma; Gray, Alice P; Njie, Madi; Riley, Eleanor M; Walther, Michael

2012-07-01

In addition to naturally occurring regulatory T (nTreg) cells derived from the thymus, functionally competent Treg cells can be induced in vitro from peripheral blood lymphocytes in response to TCR stimulation with cytokine costimulation. Using these artificial stimulation conditions, both naïve as well as memory CD4(+) T cells can be converted into induced Treg (iTreg) cells, but the cellular origin of such iTreg cells in vivo or in response to more physiologic stimulation with pathogen-derived antigens is less clear. Here, we demonstrate that a freeze/thaw lysate of Plasmodium falciparum schizont extract (PfSE) can induce functionally competent Treg cells from peripheral lymphocytes in a time- and dose-dependent manner without the addition of exogenous costimulatory factors. The PfSE-mediated induction of Treg cells required the presence of nTreg cells in the starting culture. Further experiments mixing either memory or naïve T cells with antigen presenting cells and CFSE-labeled Treg cells identified CD4(+) CD45RO(+) CD25(-) memory T cells rather than Treg cells as the primary source of PfSE-induced Treg cells. Taken together, these data suggest that in the presence of nTreg cells, PfSE induces memory T cells to convert into iTreg cells that subsequently expand alongside PfSE-induced effector T cells. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Simulated Microgravity Alters Actin Cytoskeleton and Integrin-Mediated Focal Adhesions of Cultured Human Mesenchymal Stromal Cells

Science.gov (United States)

Gershovich, P. M.; Gershovic, J. G.; Buravkova, L. B.

2008-06-01

Cytoskeletal alterations occur in several cell types including lymphocytes, glial cells, and osteoblasts, during spaceflight and under simulated microgravity (SMG) (3, 4). One potential mechanism for cytoskeletal gravisensitivity is disruption of extracellular matrix (ECM) and integrin interactions. Focal adhesions are specialized sites of cell-matrix interaction composed of integrins and the diversity of focal adhesion-associated cytoplasmic proteins including vinculin, talin, α-actinin, and actin filaments (4, 5). Integrins produce signals essential for proper cellular function, survival and differentiation. Therefore, we investigated the effects of SMG on F-actin cytoskeleton structure, vinculin focal adhesions, expression of some integrin subtypes and cellular adhesion molecules (CAMs) in mesenchymal stem cells derived from human bone marrow (hMSCs). Simulated microgravity was produced by 3D-clinostat (Dutch Space, Netherlands). Staining of actin fibers with TRITC-phalloidin showed reorganization even after 30 minutes of simulated microgravity. The increasing of cells number with abnormal F-actin was observed after subsequent terms of 3D-clinorotation (6, 24, 48, 120 hours). Randomization of gravity vector altered dimensional structure of stress fibers and resulted in remodeling of actin fibers inside the cells. In addition, we observed vinculin redistribution inside the cells after 6 hours and prolonged terms of clinorotation. Tubulin fibers in a contrast with F-actin and vinculin didn't show any reorganization even after long 3Dclinorotation (120 hours). The expression of integrin α2 increased 1,5-6-fold in clinorotated hMSCs. Also we observed decrease in number of VCAM-1-positive cells and changes in expression of ICAM-1. Taken together, our findings indicate that SMG leads to microfilament and adhesion alterations of hMSCs most probably associated with involvement of some integrin subtypes.

Angiogenin enhances cell migration by regulating stress fiber assembly and focal adhesion dynamics.

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Saisai Wei

Full Text Available Angiogenin (ANG acts on both vascular endothelial cells and cancer cells, but the underlying mechanism remains elusive. In this study, we carried out a co-immunoprecipitation assay in HeLa cells and identified 14 potential ANG-interacting proteins. Among these proteins, β-actin, α-actinin 4, and non-muscle myosin heavy chain 9 are stress fiber components and involved in cytoskeleton organization and movement, which prompted us to investigate the mechanism of action of ANG in cell migration. Upon confirmation of the interactions between ANG and the three proteins, further studies revealed that ANG co-localized with β-actin and α-actinin 4 at the leading edge of migrating cells. Down-regulation of ANG resulted in fewer but thicker stress fibers with less dynamics, which was associated with the enlargements of focal adhesions. The focal adhesion kinase activity and cell migration capacity were significantly decreased in ANG-deficient cells. Taken together, our data demonstrated that the existence of ANG in the cytoplasm optimizes stress fiber assembly and focal adhesion formation to accommodate cell migration. The finding that ANG promoted cancer cell migration might provide new clues for tumor metastasis research.

Resveratrol and Estradiol Exert Disparate Effects on Cell Migration, Cell Surface Actin Structures, and Focal Adhesion Assembly in MDA-MB-231 Human Breast Cancer Cells

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Nicolas G. Azios

2005-02-01

Full Text Available Resveratrol, a grape polyphenol, is thought to be a cancer preventive, yet its effects on metastatic breast cancer are relatively unknown. Since cancer cell invasion is dependent on cell migration, the chemotactic response of MDA-MB-231 metastatic human breast cancer cells to resveratrol, estradiol (E2, or epidermal growth factor (EGF was investigated. Resveratrol decreased while E2 and EGF increased directed cell migration. Resveratrol may inhibit cell migration by altering the cytoskeleton. Resveratrol induced a rapid global array of filopodia and decreased focal adhesions and focal adhesion kinase (FAK activity. E2 or EGF treatment did not affect filopodia extension but increased lamellipodia and associated focal adhesions that are integral for cell migration. Combined resveratrol and E2 treatment resulted in a filopodia and focal adhesion response similar to resveratrol alone. Combined resveratrol and EGF resulted in a lamellipodia and focal adhesion response similar to EGF alone. E2 and to a lesser extent resveratrol increased EGFR activity. The cytoskeletal changes and EGFR activity in response to E2 were blocked by EGFR1 inhibitor indicating that E2 may increase cell migration via crosstalk with EGFR signaling. These data suggest a promotional role for E2 in breast cancer cell migration but an antiestrogenic, preventative role for resveratrol.

Proliferating cells in HIV and pamidronate-associated collapsing focal segmental glomerulosclerosis are parietal epithelial cells.

NARCIS (Netherlands)

Dijkman, H.B.P.M.; Weening, J.J.; Smeets, B.; Verrijp, K.; Kuppevelt, A.H.M.S.M. van; Assmann, K.K.; Steenbergen, E.; Wetzels, J.F.M.

2006-01-01

Collapsing focal segmental glomerulosclerosis (cFSGS) is characterized by hyperplasia of glomerular epithelial cells. In a mouse model of FSGS and in a patient with recurrent idiopathic FSGS, we identified the proliferating cells as parietal epithelial cells (PECs). In the present study, we have

Proliferating cells in HIV and pamidronate-associated collapsing focal segmental glomerulosclerosis are parietal epithelial cells

NARCIS (Netherlands)

Dijkman, H. B. P. M.; Weening, J. J.; Smeets, B.; Verrijp, K. C. N.; van Kuppevelt, T. H.; Assmann, K. K. J. M.; Steenbergen, E. J.; Wetzels, J. F. M.

2006-01-01

Collapsing focal segmental glomerulosclerosis (cFSGS) is characterized by hyperplasia of glomerular epithelial cells. In a mouse model of FSGS and in a patient with recurrent idiopathic FSGS, we identified the proliferating cells as parietal epithelial cells (PECs). In the present study, we have

Combining PALM and SOFI for quantitative imaging of focal adhesions in living cells

Science.gov (United States)

Deschout, Hendrik; Lukes, Tomas; Sharipov, Azat; Feletti, Lely; Lasser, Theo; Radenovic, Aleksandra

2017-02-01

Focal adhesions are complicated assemblies of hundreds of proteins that allow cells to sense their extracellular matrix and adhere to it. Although most focal adhesion proteins have been identified, their spatial organization in living cells remains challenging to observe. Photo-activated localization microscopy (PALM) is an interesting technique for this purpose, especially since it allows estimation of molecular parameters such as the number of fluorophores. However, focal adhesions are dynamic entities, requiring a temporal resolution below one minute, which is difficult to achieve with PALM. In order to address this problem, we merged PALM with super-resolution optical fluctuation imaging (SOFI) by applying both techniques to the same data. Since SOFI tolerates an overlap of single molecule images, it can improve the temporal resolution compared to PALM. Moreover, an adaptation called balanced SOFI (bSOFI) allows estimation of molecular parameters, such as the fluorophore density. We therefore performed simulations in order to assess PALM and SOFI for quantitative imaging of dynamic structures. We demonstrated the potential of our PALM-SOFI concept as a quantitative imaging framework by investigating moving focal adhesions in living cells.

Focal adhesion kinase-dependent focal adhesion recruitment of SH2 domains directs SRC into focal adhesions to regulate cell adhesion and migration.

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Wu, Jui-Chung; Chen, Yu-Chen; Kuo, Chih-Ting; Wenshin Yu, Helen; Chen, Yin-Quan; Chiou, Arthur; Kuo, Jean-Cheng

2015-12-18

Directed cell migration requires dynamical control of the protein complex within focal adhesions (FAs) and this control is regulated by signaling events involving tyrosine phosphorylation. We screened the SH2 domains present in tyrosine-specific kinases and phosphatases found within FAs, including SRC, SHP1 and SHP2, and examined whether these enzymes transiently target FAs via their SH2 domains. We found that the SRC_SH2 domain and the SHP2_N-SH2 domain are associated with FAs, but only the SRC_SH2 domain is able to be regulated by focal adhesion kinase (FAK). The FAK-dependent association of the SRC_SH2 domain is necessary and sufficient for SRC FA targeting. When the targeting of SRC into FAs is inhibited, there is significant suppression of SRC-mediated phosphorylation of paxillin and FAK; this results in an inhibition of FA formation and maturation and a reduction in cell migration. This study reveals an association between FAs and the SRC_SH2 domain as well as between FAs and the SHP2_N-SH2 domains. This supports the hypothesis that the FAK-regulated SRC_SH2 domain plays an important role in directing SRC into FAs and that this SRC-mediated FA signaling drives cell migration.

Seven tesla MRI improves detection of focal cortical dysplasia in patients with refractory focal epilepsy

NARCIS (Netherlands)

Veersema, Tim J; Ferrier, Cyrille H; van Eijsden, Pieter; Gosselaar, Peter H; Aronica, Eleonora; Visser, Fredy; Zwanenburg, Jaco M; de Kort, Gerard A P; Hendrikse, Jeroen; Luijten, Peter R; Braun, Kees P J

Objective: The aim of this study is to determine whether the use of 7 tesla (T) MRI in clinical practice leads to higher detection rates of focal cortical dysplasias in possible candidates for epilepsy surgery. Methods: In our center patients are referred for 7 T MRI if lesional focal epilepsy is

Destructive impact of t-lymphocytes, NK and mast cells on basal cell layers: implications for tumor invasion

International Nuclear Information System (INIS)

Yuan, Hongyan; Hsiao, Yi-Hsuan; Zhang, Yiyu; Wang, Jinlian; Yin, Chao; Shen, Rong; Su, Yiping

2013-01-01

Our previous studies have suggested that the primary impact of immune cell infiltration into the normal or pre-invasive tissue component is associated with the physical destruction of epithelial capsules, which may promote tumor progression and invasion. Our current study attempted to further verify our previous observations and determine the primary type(s) of infiltrating immune cells and the possible mechanism associated with physical destructions of the epithelial capsules. In total, the study was conducted with 250 primary breast and prostate tumors, the primary immune cell of cytotoxic T-lymphocytes (CTL), Natural killer cells (NK) and Mast cells were analyzed by immunohistochemistry, fluorescent labeling and apoptosis assay. qRT-PCR was used for gene expression analysis. Our current study assessed the physical disruption of these immune cells and potential impact on the epithelial capsule of human breast and prostate tumors. Our study yield several clinically-relevant findings that have not been studied before. (1) A vast majority of these infiltrating immune cells are distributed in the normal-appearing or pre-invasive tissue components rather than in invasive cancer tissues. (2) These cells often form rings or semilunar structures that either surround focally-disrupted basal cell layers or physically attach to the basal cells. (3) Basal cells physically associated with these immune cells generally displayed distinct signs of degeneration, including substantially elevated apoptosis, necrosis, and reduced tumor suppressor p63 expression. In contrast, luminal cells overlying focally disrupted basal cell layers had a substantially increased proliferation rate and elevated expression of stem cell markers compared to their adjacent morphologically similar counterparts that overlie a non-disrupted capsule. Our findings suggest that at the early stage of tumor invasion, CTL, NK and Mast cells are the main types of tumor infiltrating immune cells involved in focal

Biogenesis and function of T cell-derived exosomes

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Miguel Angel Alonso

2016-08-01

Full Text Available Exosomes are a particular type of extracellular vesicle, characterized by their endosomal origin as intraluminal vesicles present in large endosomes with a multivesicular structure. After these endosomes fuse with the plasma membrane, exosomes are secreted into the extracellular space. The ability of exosomes to carry and selectively deliver bioactive molecules (e.g., lipids, proteins and nucleic acids confers on them the capacity to modulate the activity of receptor cells, even if these cells are located in distant tissues or organs. Since exosomal cargo depends on cell type, a detailed understanding of the mechanisms that regulate the biochemical composition of exosomes is fundamental to a comprehensive view of exosome function. Here, we review the latest advances concerning exosome function and biogenesis in T cells, with particular focus on the mechanism of protein sorting at multivesicular endosomes. Exosomes secreted by specific T-cell subsets can modulate the activity of immune cells, including other T-cell subsets. Ceramide, tetraspanins and MAL have been revealed to be important in exosome biogenesis by T cells. These molecules, therefore, constitute potential molecular targets for artificially modulating exosome production and, hence, the immune response for therapeutic purposes.

Signal characteristics of focal bone marrow lesions in patients with multiple myeloma using whole body T1w-TSE, T2w-STIR and diffusion-weighted imaging with background suppression

Energy Technology Data Exchange (ETDEWEB)

Sommer, Gregor; Bongartz, Georg; Winter, Leopold [University of Basel Hospital, Department of Radiology, Basel (Switzerland); Klarhoefer, Markus; Lenz, Claudia; Scheffler, Klaus [University of Basel Hospital, Department of Radiology, Division of Radiological Physics, Basel (Switzerland)

2011-04-15

This study analyses the diagnostic potential of Diffusion-Weighted Imaging with Background Suppression (DWIBS) in the detection of focal bone marrow lesions from multiple myeloma. The signal and contrast properties of DWIBS are evaluated in correlation with the serum concentration of M-component (MC) and compared with established T1- and T2-weighted sequences. Data from 103 consecutive studies in 81 patients are analysed retrospectively. Signal intensities and apparent Diffusion Coefficients (ADC) of 79 focal lesions in the lumbar spine or pelvis of 38 patients are determined and contrast-to-noise-ratio (CNR) is calculated. Data from patients with low (<20 g/L) and high (>20 g/dL) MC are evaluated separately. Signal intensities of focal myeloma lesions on T2w-STIR vary significantly depending on the MC, which leads to a loss in CNR in patients with high MC. No signal variation is observed for T1w-TSE and DWIBS. The CNR values provided by DWIBS in patients with high MC are slightly higher than those of T2w-STIR. ADC values in patients with low MC are significantly higher than in patients with high MC. Whole-body DWIBS has the potential to improve the conspicuity of focal myeloma lesions and provides additional biological information by ADC quantification. (orig.)

PDGFBB promotes PDGFRα-positive cell migration into artificial bone in vivo

International Nuclear Information System (INIS)

Yoshida, Shigeyuki; Iwasaki, Ryotaro; Kawana, Hiromasa; Miyauchi, Yoshiteru; Hoshi, Hiroko; Miyamoto, Hiroya; Mori, Tomoaki; Kanagawa, Hiroya; Katsuyama, Eri; Fujie, Atsuhiro; Hao, Wu

2012-01-01

Highlights: ► We examined effects of PDGFBB in PDGFRα positive cell migration in artificial bones. ► PDGFBB was not expressed in osteoblastic cells but was expressed in peripheral blood cells. ► PDGFBB promoted PDGFRα positive cell migration into artificial bones but not osteoblast proliferation. ► PDGFBB did not inhibit osteoblastogenesis. -- Abstract: Bone defects caused by traumatic bone loss or tumor dissection are now treated with auto- or allo-bone graft, and also occasionally by artificial bone transplantation, particularly in the case of large bone defects. However, artificial bones often exhibit poor affinity to host bones followed by bony union failure. Thus therapies combining artificial bones with growth factors have been sought. Here we report that platelet derived growth factor bb (PDGFBB) promotes a significant increase in migration of PDGF receptor α (PDGFRα)-positive mesenchymal stem cells/pre-osteoblastic cells into artificial bone in vivo. Growth factors such as transforming growth factor beta (TGFβ) and hepatocyte growth factor (HGF) reportedly inhibit osteoblast differentiation; however, PDGFBB did not exhibit such inhibitory effects and in fact stimulated osteoblast differentiation in vitro, suggesting that combining artificial bones with PDGFBB treatment could promote host cell migration into artificial bones without inhibiting osteoblastogenesis.

A Nanodot Array Modulates Cell Adhesion and Induces an Apoptosis-Like Abnormality in NIH-3T3 Cells

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Hung Yao-Ching

2009-01-01

Full Text Available Abstract Micro-structures that mimic the extracellular substratum promote cell growth and differentiation, while the cellular reaction to a nanostructure is poorly defined. To evaluate the cellular response to a nanoscaled surface, NIH 3T3 cells were grown on nanodot arrays with dot diameters ranging from 10 to 200 nm. The nanodot arrays were fabricated by AAO processing on TaN-coated wafers. A thin layer of platinum, 5 nm in thickness, was sputtered onto the structure to improve biocompatibility. The cells grew normally on the 10-nm array and on flat surfaces. However, 50-nm, 100-nm, and 200-nm nanodot arrays induced apoptosis-like events. Abnormality was triggered after as few as 24 h of incubation on a 200-nm dot array. For cells grown on the 50-nm array, the abnormality started after 72 h of incubation. The number of filopodia extended from the cell bodies was lower for the abnormal cells. Immunostaining using antibodies against vinculin and actin filament was performed. Both the number of focal adhesions and the amount of cytoskeleton were decreased in cells grown on the 100-nm and 200-nm arrays. Pre-coatings of fibronectin (FN or type I collagen promoted cellular anchorage and prevented the nanotopography-induced programed cell death. In summary, nanotopography, in the form of nanodot arrays, induced an apoptosis-like abnormality for cultured NIH 3T3 cells. The occurrence of the abnormality was mediated by the formation of focal adhesions.

Cancer Patient T Cells Genetically Targeted to Prostate-Specific Membrane Antigen Specifically Lyse Prostate Cancer Cells and Release Cytokines in Response to Prostate-Specific Membrane Antigen

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Michael C. Gong

1999-06-01

Full Text Available The expression of immunoglobulin-based artificial receptors in normal T lymphocytes provides a means to target lymphocytes to cell surface antigens independently of major histocompatibility complex restriction. Such artificial receptors have been previously shown to confer antigen-specific tumoricidal properties in murine T cells. We constructed a novel ζ chain fusion receptor specific for prostate-specific membrane antigen (PSMA termed Pz-1. PSMA is a cell-surface glycoprotein expressed on prostate cancer cells and the neovascular endothelium of multiple carcinomas. We show that primary T cells harvested from five of five patients with different stages of prostate cancer and transduced with the Pz-1 receptor readily lyse prostate cancer cells. Having established a culture system using fibroblasts that express PSMA, we next show that T cells expressing the Pz-1 receptor release cytokines in response to cell-bound PSMA. Furthermore, we show that the cytokine release is greatly augmented by B7.1-mediated costimulation. Thus, our findings support the feasibility of adoptive cell therapy by using genetically engineered T cells in prostate cancer patients and suggest that both CD4+ and CD8+ T lymphocyte functions can be synergistically targeted against tumor cells.

The role of CD8+ T cells during allograft rejection

Directory of Open Access Journals (Sweden)

V. Bueno

2002-11-01

Full Text Available Organ transplantation can be considered as replacement therapy for patients with end-stage organ failure. The percent of one-year allograft survival has increased due, among other factors, to a better understanding of the rejection process and new immunosuppressive drugs. Immunosuppressive therapy used in transplantation prevents activation and proliferation of alloreactive T lymphocytes, although not fully preventing chronic rejection. Recognition by recipient T cells of alloantigens expressed by donor tissues initiates immune destruction of allogeneic transplants. However, there is controversy concerning the relative contribution of CD4+ and CD8+ T cells to allograft rejection. Some animal models indicate that there is an absolute requirement for CD4+ T cells in allogeneic rejection, whereas in others CD4-depleted mice reject certain types of allografts. Moreover, there is evidence that CD8+ T cells are more resistant to immunotherapy and tolerance induction protocols. An intense focal infiltration of mainly CD8+CTLA4+ T lymphocytes during kidney rejection has been described in patients. This suggests that CD8+ T cells could escape from immunosuppression and participate in the rejection process. Our group is primarily interested in the immune mechanisms involved in allograft rejection. Thus, we believe that a better understanding of the role of CD8+ T cells in allograft rejection could indicate new targets for immunotherapy in transplantation. Therefore, the objective of the present review was to focus on the role of the CD8+ T cell population in the rejection of allogeneic tissue.

Reorganization of the actin cytoskeleton via transcriptional regulation of cytoskeletal/focal adhesion genes by myocardin-related transcription factors (MRTFs/MAL/MKLs)

International Nuclear Information System (INIS)

Morita, Tsuyoshi; Mayanagi, Taira; Sobue, Kenji

2007-01-01

RhoA is a crucial regulator of stress fiber and focal adhesion formation through the activation of actin nucleation and polymerization. It also regulates the nuclear translocation of myocardin-related transcription factor-A and -B (MRTF-A/B, MAL or MKL 1/2), which are co-activators of serum response factor (SRF). In dominant-negative MRTF-A (DN-MRTF-A)-expressing NIH 3T3 cell lines, the expressions of several cytoskeletal/focal adhesion genes were down-regulated, and the formation of stress fiber and focal adhesion was severely diminished. MRTF-A/B-knockdown cells also exhibited such cytoskeletal defects. In reporter assays, both RhoA and MRTF-A enhanced promoter activities of these genes in a CArG-box-dependent manner, and DN-MRTF-A inhibited the RhoA-mediated activation of these promoters. In dominant-negative RhoA (RhoA-N19)-expressing NIH 3T3 cell lines, the nuclear translocation of MRTF-A/B was predominantly prevented, resulting in the reduced expression of cytoskeletal/focal adhesion proteins. Further, constitutive-active MRTF-A/B increased the expression of endogenous cytoskeletal/focal adhesion proteins, and thereby rescued the defective phenotype of stress fibers and focal adhesions in RhoA-N19 expressing cells. These results indicate that MRTF-A/B act as pivotal mediators of stress fiber and focal adhesion formation via the transcriptional regulation of a subset of cytoskeletal/focal adhesion genes

PDGFBB promotes PDGFR{alpha}-positive cell migration into artificial bone in vivo

Energy Technology Data Exchange (ETDEWEB)

Yoshida, Shigeyuki [Department of Dentistry and Oral Surgery, Keio University School of Medicine, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582 (Japan); Center for Human Metabolomic Systems Biology, Keio University School of Medicine, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582 (Japan); Iwasaki, Ryotaro; Kawana, Hiromasa [Department of Dentistry and Oral Surgery, Keio University School of Medicine, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582 (Japan); Miyauchi, Yoshiteru [Center for Human Metabolomic Systems Biology, Keio University School of Medicine, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582 (Japan); Department of Orthopedic Surgery, Keio University School of Medicine, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582 (Japan); Department of Integrated Bone Metabolism and Immunology, Keio University School of Medicine, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582 (Japan); Hoshi, Hiroko; Miyamoto, Hiroya; Mori, Tomoaki [Center for Human Metabolomic Systems Biology, Keio University School of Medicine, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582 (Japan); Department of Orthopedic Surgery, Keio University School of Medicine, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582 (Japan); Kanagawa, Hiroya [Department of Orthopedic Surgery, Keio University School of Medicine, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582 (Japan); Katsuyama, Eri; Fujie, Atsuhiro [Center for Human Metabolomic Systems Biology, Keio University School of Medicine, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582 (Japan); Department of Orthopedic Surgery, Keio University School of Medicine, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582 (Japan); Hao, Wu [Department of Orthopedic Surgery, Keio University School of Medicine, 35 Shinano-machi, Shinjuku-ku, Tokyo 160-8582 (Japan); and others

2012-05-18

Highlights: Black-Right-Pointing-Pointer We examined effects of PDGFBB in PDGFR{alpha} positive cell migration in artificial bones. Black-Right-Pointing-Pointer PDGFBB was not expressed in osteoblastic cells but was expressed in peripheral blood cells. Black-Right-Pointing-Pointer PDGFBB promoted PDGFR{alpha} positive cell migration into artificial bones but not osteoblast proliferation. Black-Right-Pointing-Pointer PDGFBB did not inhibit osteoblastogenesis. -- Abstract: Bone defects caused by traumatic bone loss or tumor dissection are now treated with auto- or allo-bone graft, and also occasionally by artificial bone transplantation, particularly in the case of large bone defects. However, artificial bones often exhibit poor affinity to host bones followed by bony union failure. Thus therapies combining artificial bones with growth factors have been sought. Here we report that platelet derived growth factor bb (PDGFBB) promotes a significant increase in migration of PDGF receptor {alpha} (PDGFR{alpha})-positive mesenchymal stem cells/pre-osteoblastic cells into artificial bone in vivo. Growth factors such as transforming growth factor beta (TGF{beta}) and hepatocyte growth factor (HGF) reportedly inhibit osteoblast differentiation; however, PDGFBB did not exhibit such inhibitory effects and in fact stimulated osteoblast differentiation in vitro, suggesting that combining artificial bones with PDGFBB treatment could promote host cell migration into artificial bones without inhibiting osteoblastogenesis.

Focal adhesion kinase maintains, but not increases the adhesion of dental pulp cells.

Science.gov (United States)

Qian, Yuyan; Shao, Meiying; Zou, Wenlin; Wang, Linyan; Cheng, Ran; Hu, Tao

2017-04-01

Focal adhesion kinase (FAK) functions as a key enzyme in the integrin-mediated adhesion-signalling pathway. Here, we aimed to investigate the effects of FAK on adhesion of human dental pulp (HDP) cells. We transfected lentiviral vectors to silence or overexpress FAK in HDP cells ex vivo. Early cell adhesion, cell survival and focal contacts (FCs)-related proteins (FAK and paxillin) were examined. By using immunofluorescence, the formation of FCs and cytoskeleton was detected, respectively. We found that both adhesion and survival of HDP cells were suppressed by FAK inhibition. However, FAK overexpression slightly inhibited cell adhesion and exhibited no change in cell survival compared with the control. A thick rim of cytoskeleton accumulated and smaller dot-shaped FCs appeared in FAK knockdown cells. Phosphorylation of paxillin (p-paxillin) was inhibited in FAK knockdown cells, verifying that the adhesion was inhibited. Less cytoskeleton and elongated FCs were observed in FAK-overexpressed cells. However, p-paxillin had no significant difference compared with the control. In conclusion, the data suggest that FAK maintains cell adhesion, survival and cytoskeleton formation, but excessive FAK has no positive effects on these aspects.

Artificial engineering of secondary lymphoid organs.

Science.gov (United States)

Tan, Jonathan K H; Watanabe, Takeshi

2010-01-01

Secondary lymphoid organs such as spleen and lymph nodes are highly organized immune structures essential for the initiation of immune responses. They display distinct B cell and T cell compartments associated with specific stromal follicular dendritic cells and fibroblastic reticular cells, respectively. Interweaved through the parenchyma is a conduit system that distributes small antigens and chemokines directly to B and T cell zones. While most structural aspects between lymph nodes and spleen are common, the entry of lymphocytes, antigen-presenting cells, and antigen into lymphoid tissues is regulated differently, reflecting the specialized functions of each organ in filtering either lymph or blood. The overall organization of lymphoid tissue is vital for effective antigen screening and recognition, and is a feature which artificially constructed lymphoid organoids endeavor to replicate. Synthesis of artificial lymphoid tissues is an emerging field that aims to provide therapeutic application for the treatment of severe infection, cancer, and age-related involution of secondary lymphoid tissues. The development of murine artificial lymphoid tissues has benefited greatly from an understanding of organogenesis of lymphoid organs, which has delineated cellular and molecular elements essential for the recruitment and organization of lymphocytes into lymphoid structures. Here, the field of artificial lymphoid tissue engineering is considered including elements of lymphoid structure and development relevant to organoid synthesis. (c) 2010 Elsevier Inc. All rights reserved.

Modelling fuel cell performance using artificial intelligence

Science.gov (United States)

Ogaji, S. O. T.; Singh, R.; Pilidis, P.; Diacakis, M.

Over the last few years, fuel cell technology has been increasing promisingly its share in the generation of stationary power. Numerous pilot projects are operating worldwide, continuously increasing the amount of operating hours either as stand-alone devices or as part of gas turbine combined cycles. An essential tool for the adequate and dynamic analysis of such systems is a software model that enables the user to assess a large number of alternative options in the least possible time. On the other hand, the sphere of application of artificial neural networks has widened covering such endeavours of life such as medicine, finance and unsurprisingly engineering (diagnostics of faults in machines). Artificial neural networks have been described as diagrammatic representation of a mathematical equation that receives values (inputs) and gives out results (outputs). Artificial neural networks systems have the capacity to recognise and associate patterns and because of their inherent design features, they can be applied to linear and non-linear problem domains. In this paper, the performance of the fuel cell is modelled using artificial neural networks. The inputs to the network are variables that are critical to the performance of the fuel cell while the outputs are the result of changes in any one or all of the fuel cell design variables, on its performance. Critical parameters for the cell include the geometrical configuration as well as the operating conditions. For the neural network, various network design parameters such as the network size, training algorithm, activation functions and their causes on the effectiveness of the performance modelling are discussed. Results from the analysis as well as the limitations of the approach are presented and discussed.

Modelling fuel cell performance using artificial intelligence

Energy Technology Data Exchange (ETDEWEB)

Ogaji, S.O.T.; Singh, R.; Pilidis, P.; Diacakis, M. [Power Propulsion and Aerospace Engineering Department, Centre for Diagnostics and Life Cycle Costs, Cranfield University (United Kingdom)

2006-03-09

Over the last few years, fuel cell technology has been increasing promisingly its share in the generation of stationary power. Numerous pilot projects are operating worldwide, continuously increasing the amount of operating hours either as stand-alone devices or as part of gas turbine combined cycles. An essential tool for the adequate and dynamic analysis of such systems is a software model that enables the user to assess a large number of alternative options in the least possible time. On the other hand, the sphere of application of artificial neural networks has widened covering such endeavours of life such as medicine, finance and unsurprisingly engineering (diagnostics of faults in machines). Artificial neural networks have been described as diagrammatic representation of a mathematical equation that receives values (inputs) and gives out results (outputs). Artificial neural networks systems have the capacity to recognise and associate patterns and because of their inherent design features, they can be applied to linear and non-linear problem domains. In this paper, the performance of the fuel cell is modelled using artificial neural networks. The inputs to the network are variables that are critical to the performance of the fuel cell while the outputs are the result of changes in any one or all of the fuel cell design variables, on its performance. Critical parameters for the cell include the geometrical configuration as well as the operating conditions. For the neural network, various network design parameters such as the network size, training algorithm, activation functions and their causes on the effectiveness of the performance modelling are discussed. Results from the analysis as well as the limitations of the approach are presented and discussed. (author)

Merkel Cell Polyomavirus Small T Antigen Induces Cancer and Embryonic Merkel Cell Proliferation in a Transgenic Mouse Model.

Science.gov (United States)

Shuda, Masahiro; Guastafierro, Anna; Geng, Xuehui; Shuda, Yoko; Ostrowski, Stephen M; Lukianov, Stefan; Jenkins, Frank J; Honda, Kord; Maricich, Stephen M; Moore, Patrick S; Chang, Yuan

2015-01-01

Merkel cell polyomavirus (MCV) causes the majority of human Merkel cell carcinomas (MCC) and encodes a small T (sT) antigen that transforms immortalized rodent fibroblasts in vitro. To develop a mouse model for MCV sT-induced carcinogenesis, we generated transgenic mice with a flox-stop-flox MCV sT sequence homologously recombined at the ROSA locus (ROSAsT), allowing Cre-mediated, conditional MCV sT expression. Standard tamoxifen (TMX) administration to adult UbcCreERT2; ROSAsT mice, in which Cre is ubiquitously expressed, resulted in MCV sT expression in multiple organs that was uniformly lethal within 5 days. Conversely, most adult UbcCreERT2; ROSAsT mice survived low-dose tamoxifen administration but developed ear lobe dermal hyperkeratosis and hypergranulosis. Simultaneous MCV sT expression and conditional homozygous p53 deletion generated multi-focal, poorly-differentiated, highly anaplastic tumors in the spleens and livers of mice after 60 days of TMX treatment. Mouse embryonic fibroblasts from these mice induced to express MCV sT exhibited anchorage-independent cell growth. To examine Merkel cell pathology, MCV sT expression was also induced during mid-embryogenesis in Merkel cells of Atoh1CreERT2/+; ROSAsT mice, which lead to significantly increased Merkel cell numbers in touch domes at late embryonic ages that normalized postnatally. Tamoxifen administration to adult Atoh1CreERT2/+; ROSAsT and Atoh1CreERT2/+; ROSAsT; p53flox/flox mice had no effects on Merkel cell numbers and did not induce tumor formation. Taken together, these results show that MCV sT stimulates progenitor Merkel cell proliferation in embryonic mice and is a bona fide viral oncoprotein that induces full cancer cell transformation in the p53-null setting.

T cell receptor-engineered T cells to treat solid tumors: T cell processing toward optimal T cell fitness

NARCIS (Netherlands)

C.H.J. Lamers (Cor); S. van Steenbergen-Langeveld (Sabine); M. van Brakel (Mandy); C.M. Groot-van Ruijven (Corrien); P.M.M.L. van Elzakker (Pascal); B.A. van Krimpen (Brigitte); S. Sleijfer (Stefan); J.E.M.A. Debets (Reno)

2014-01-01

textabstractTherapy with autologous T cells that have been gene-engineered to express chimeric antigen receptors (CAR) or T cell receptors (TCR) provides a feasible and broadly applicable treatment for cancer patients. In a clinical study in advanced renal cell carcinoma (RCC) patients with CAR T

Multicompartment Artificial Organelles Conducting Enzymatic Cascade Reactions inside Cells

DEFF Research Database (Denmark)

Gallardo, Maria Godoy; Labay, Cédric Pierre; Trikalitis, Vasileios

2017-01-01

Cell organelles are subcellular structures entrapping a set of enzymes to achieve a specific functionality. The incorporation of artificial organelles into cells is a novel medical paradigm which might contribute to the treatment of various cell disorders by replacing malfunctioning organelles....... In particular, artificial organelles are expected to be a powerful solution in the context of enzyme replacement therapy since enzymatic malfunction is the primary cause of organelle dysfunction. Although several attempts have been made to encapsulate enzymes within a carrier vehicle, only few intracellularly...

Flotillins Regulate Focal Adhesions by Interacting with α-Actinin and by Influencing the Activation of Focal Adhesion Kinase

Directory of Open Access Journals (Sweden)

Antje Banning

2018-04-01

Full Text Available Cell–matrix adhesion and cell migration are physiologically important processes that also play a major role in cancer spreading. In cultured cells, matrix adhesion depends on integrin-containing contacts such as focal adhesions. Flotillin-1 and flotillin-2 are frequently overexpressed in cancers and are associated with poor survival. Our previous studies have revealed a role for flotillin-2 in cell–matrix adhesion and in the regulation of the actin cytoskeleton. We here show that flotillins are important for cell migration in a wound healing assay and influence the morphology and dynamics of focal adhesions. Furthermore, anchorage-independent growth in soft agar is enhanced by flotillins. In the absence of flotillins, especially flotillin-2, phosphorylation of focal adhesion kinase and extracellularly regulated kinase is diminished. Flotillins interact with α-actinin, a major regulator of focal adhesion dynamics. These findings are important for understanding the molecular mechanisms of how flotillin overexpression in cancers may affect cell migration and, especially, enhance metastasis formation.

Focal degeneration of basal cells and the resultant auto-immunoreactions: a novel mechanism for prostate tumor progression and invasion.

Science.gov (United States)

Man, Yan-Gao; Gardner, William A

2008-01-01

The development of human prostate cancer is believed to be a multistep process, progressing sequentially from normal, to hyperplasia, to prostatic intraepithelial neoplasia (PIN), and to invasive and metastatic lesions. High grade PIN has been generally considered as the direct precursor of invasive lesions, and the progression of PIN is believed to be triggered primarily, if not solely, by the overproduction of proteolytic enzymes predominately by cancer cells, which result in the degradation of the basement membrane. These theories, however, are hard to reconcile with two main facts: (1) only about 30% untreated PIN progress to invasive stage, while none of the current approaches could accurately identify the specific PIN or individuals at greater risk for progression, and (2) results from recent world-wide clinical trials with a wide variety of proteolytic enzyme inhibitors have been very disappointing, casting doubt on the validity of the proteolytic enzyme theory. Since over 90% of prostate cancer-related deaths result from invasion-related illness and the incidence of PIN could be up to 16.5-25% in routine or ultrasound guided prostate biopsy, there is an urgent need to uncover the intrinsic mechanism of prostate tumor invasion. Promoted by the facts that the basal cell population is the source of several tumor suppressors and the absence of the basal cell layer is the most distinct feature of invasive lesions, our recent studies have intended to identify the early alterations of basal cell layers and their impact on tumor invasion using multidisciplinary approaches. Our studies revealed that a subset of pre-invasive tumors contained focal disruptions (the absence of basal cells resulting in a gap greater than the combined size of at least three epithelial cells) in surrounding basal cell layers. Compared to their non-disrupted counterparts, focally disrupted basal cell layers had several unique features: (1) significantly lower proliferation; (2

Common histological patterns in glomerular epithelial cells in secondary focal segmental glomerulosclerosis

NARCIS (Netherlands)

Kuppe, C.; Grone, H.J.; Ostendorf, T.; Kuppevelt, T.H. van; Boor, P.; Floege, J.; Smeets, B.; Moeller, M.J.

2015-01-01

Parietal epithelial cells (PECs) are involved in the development of sclerotic lesions in primary focal and segmental glomerulosclerosis (FSGS). Here, the role of PECs was explored in the more common secondary FSGS lesions in 68 patient biopsies, diagnosed with 11 different frequently or rarely

Antigen-driven focal inflammatory death of malaria liver stages

Directory of Open Access Journals (Sweden)

Ganchimeg eBayarsaikhan

2015-02-01

Full Text Available Multiple immunizations using live irradiated sporozoites, the infectious plasmodial stage delivered into the host skin during a mosquito bite, can elicit sterile immunity to malaria. CD8+ T cells seem to play an essential role in this protective immunity, since their depletion consistently abolishes sterilizing protection in several experimental models. So far, only a few parasite antigens are known to induce CD8+ T cell-dependent protection, but none of them can reach the levels of protection afforded by live attenuated parasites. Systematic attempts to identify novel antigens associated with this efficient cellular protection were so far unsuccessful. In addition, the precise mechanisms involved in the recognition and elimination of parasitized hepatocytes in vivo by CD8+ T cells still remain obscure. Recently, it has been shown that specific effector CD8+ T cells, after recognition of parasitized hepatocytes, recruit specific and non-specific activated CD8+ T cells to the site of infection, resulting in the formation of cellular clusters around and in the further elimination of intracellular parasites. The significance of this finding is discussed in the perspective of a general mechanism of antigen-dependent focalized inflammation and its consequences for the elimination of malaria liver stages.

Changes in microfilament and focal adhesion distribution with loss of androgen responsiveness in cultured mammary tumor cells

DEFF Research Database (Denmark)

Couchman, J R; Yates, J; King, R J

1981-01-01

of the cells to grow in suspension culture. All these parameters were documented for androgen-responsive and -unresponsive cells grown in culture, as well as the transition of androgen-responsive to -unresponsive cells when deprived of androgen. The androgen-unresponsive cells had extensive and prominent...... microfilament bundles together with focal adhesions on the lower cell surface and also showed strict anchorage dependence for growth. In contrast, microfilament bundles and focal adhesions were absent from androgen-responsive cells, which furthermore had the ability to grow in suspension culture. Differences......, characteristics of both cell types were visible in the cell populations. However, at the stage where all androgen-responsive characteristics were lost, the cells were no longer androgen sensitive. The loss of androgen responsiveness in Shionogi 115 mouse mammary tumor cells is correlated with changes at the cell...

DNA cytoskeleton for stabilizing artificial cells.

Science.gov (United States)

Kurokawa, Chikako; Fujiwara, Kei; Morita, Masamune; Kawamata, Ibuki; Kawagishi, Yui; Sakai, Atsushi; Murayama, Yoshihiro; Nomura, Shin-Ichiro M; Murata, Satoshi; Takinoue, Masahiro; Yanagisawa, Miho

2017-07-11

Cell-sized liposomes and droplets coated with lipid layers have been used as platforms for understanding live cells, constructing artificial cells, and implementing functional biomedical tools such as biosensing platforms and drug delivery systems. However, these systems are very fragile, which results from the absence of cytoskeletons in these systems. Here, we construct an artificial cytoskeleton using DNA nanostructures. The designed DNA oligomers form a Y-shaped nanostructure and connect to each other with their complementary sticky ends to form networks. To undercoat lipid membranes with this DNA network, we used cationic lipids that attract negatively charged DNA. By encapsulating the DNA into the droplets, we successfully created a DNA shell underneath the membrane. The DNA shells increased interfacial tension, elastic modulus, and shear modulus of the droplet surface, consequently stabilizing the lipid droplets. Such drastic changes in stability were detected only when the DNA shell was in the gel phase. Furthermore, we demonstrate that liposomes with the DNA gel shell are substantially tolerant against outer osmotic shock. These results clearly show the DNA gel shell is a stabilizer of the lipid membrane akin to the cytoskeleton in live cells.

Umbilical cord blood regulatory T-cell expansion and functional effects of tumor necrosis factor receptor family members OX40 and 4-1BB expressed on artificial antigen-presenting cells

Science.gov (United States)

Harker-Murray, Paul; Porter, Stephen B.; Merkel, Sarah C.; Londer, Aryel; Taylor, Dawn K.; Bina, Megan; Panoskaltsis-Mortari, Angela; Rubinstein, Pablo; Van Rooijen, Nico; Golovina, Tatiana N.; Suhoski, Megan M.; Miller, Jeffrey S.; Wagner, John E.; June, Carl H.; Riley, James L.

2008-01-01

Previously, we showed that human umbilical cord blood (UCB) regulatory T cells (Tregs) could be expanded approximately 100-fold using anti-CD3/28 monoclonal antibody (mAb)–coated beads to provide T-cell receptor and costimulatory signals. Because Treg numbers from a single UCB unit are limited, we explored the use of cell-based artificial antigen-presenting cells (aAPCs) preloaded with anti-CD3/28 mAbs to achieve higher levels of Treg expansion. Compared with beads, aAPCs had similar expansion properties while significantly increasing transforming growth factor β (TGF-β) secretion and the potency of Treg suppressor function. aAPCs modified to coexpress OX40L or 4-1BBL expanded UCB Tregs to a significantly greater extent than bead- or nonmodified aAPC cultures, reaching mean expansion levels exceeding 1250-fold. Despite the high expansion and in contrast to studies using other Treg sources, neither OX40 nor 4-1BB signaling of UCB Tregs reduced in vitro suppression. UCB Tregs expanded with 4-1BBL expressing aAPCs had decreased levels of proapoptotic bim. UCB Tregs expanded with nonmodified or modified aAPCs versus beads resulted in higher survival associated with increased Treg persistence in a xeno-geneic graft-versus-host disease lethality model. These data offer a novel approach for UCB Treg expansion using aAPCs, including those coexpressing OX40L or 4-1BBL. PMID:18645038

Clinical applications of gamma delta T cells with multivalent immunity

Directory of Open Access Journals (Sweden)

Drew C Deniger

2014-12-01

Full Text Available Gamma delta T cells hold promise for adoptive immunotherapy because of their reactivity to bacteria, viruses, and tumors. However, these cells represent a small fraction (1-5% of the peripheral T-cell pool and require activation and propagation to achieve clinical benefit. Aminobisphosphonates specifically expand the Vgamma9Vdelta2 subset of gamma delta T cells and have been used in clinical trials of cancer where objective responses were detected. The Vgamma9Vdelta2 TCR heterodimer binds multiple ligands and results in a multivalent attack by a monoclonal T cell population. Alternatively, populations of gamma delta T cells with oligoclonal or polyclonal TCR repertoire could be infused for broad-range specificity. However, this goal has been restricted by a lack of applicable expansion protocols for non-Vgamma9Vdelta2 cells. Recent advances using immobilized antigens, agonistic monoclonal antibodies (mAbs, tumor-derived artificial antigen presenting cells (aAPC, or combinations of activating mAbs and aAPC have been successful in expanding gamma delta T cells with oligoclonal or polyclonal TCR repertoires. Immobilized MHC Class-I chain-related A was a stimulus for gamma delta T cells expressing TCRdelta1 isotypes, and plate-bound activating antibodies have expanded Vdelta1 and Vdelta2 cells ex vivo. Clinically-sufficient quantities of TCRdelta1, TCRdelta2, and TCRdelta1negTCRdelta2neg have been produced following co-culture on aAPC, and these subsets displayed differences in memory phenotype and reactivity to tumors in vitro and in vivo. Gamma delta T cells are also amenable to genetic modification as evidenced by introduction of alpha beta TCRs, chimeric antigen receptors (CARs, and drug-resistance genes. This represents a promising future for the clinical application of oligoclonal or polyclonal gamma delta T cells in autologous and allogeneic settings that builds on current trials testing the safety and efficacy of Vgamma9Vdelta2 T cells.

Evaluation of turbo spin echo sequences for MRI of focal liver lesions at 0.5 T

International Nuclear Information System (INIS)

Kreft, B.; Layer, G.; Steudel, A.; Spiller, L.; Heuck, A.; Mueller, A.; Gieseke, J.; Reiser, M.F.

1994-01-01

To determine whether turbo spin echo (TSE) sequences can replace conventional T2-weighted spin echo (SE) sequences in MRI of the liver, 40 patients with focal liver lesions were imaged at 0.5 T. A T2-weighted SE sequence (TR/TE 1800/90 ms, number of signals averaged [NEX] = 2, scan time 7:16 min), a TSE sequence (TR/TE 1800/90 ms, NEX = 4, number of echos per excitation = 13, echo spacing = 12.9 ms, scan time = 4:16 min) and a T1-weighted SE sequence (TR/TE 350/15 ms, NEX = 2, scan time = 4:21 min) were obtained and image quality, lesion detectability and lesion differentiation were evaluated qualitatively by subjective assessment using scores and quantitatively by lesion-liver contrast-to-noise (CNR) and tumour/liver signal intensity (SI) ratios. The image quality of the TSE sequence was substantially better compared with the T2-weighted SE sequence due to a reduction in motion artefacts and better delineation of anatomical details. Of a total of 158 visible lesions the T1-weighted SE, TSE and T2-weighted SE sequences showed 91 %, 81 % and 65 % of the lesions, respectively. Thus the TSE sequence depicted 24 % (P < 0.001) more lesions than the T2-weighted SE sequence. In all types of pathology the lesion-liver CNR of the TSE sequence was significantly (P < 0.001) higher compared to the CNR of the T2-weighted SE sequence ( +55-65 %), indicating superior lesion conspicuity. Lesion characterization was equally good on the two T2-weighted sequences with no difference in the tumour/liver SI ratio. Using a criterion of tumour/liver SI ratio equal to or higher than 2, haemangiomas larger than 1 cm in diameter could be differentiated from other lesions with a sensitivity and specificity of 95 % and 96 %, respectively. Our results indicate that the TSE sequence is suitable for replacing the conventional T2-weighted SE sequence in MRI of focal liver lesions. (orig.)

Efficacy of an artificial neural network-based approach to endoscopic ultrasound elastography in diagnosis of focal pancreatic masses.

Science.gov (United States)

Săftoiu, Adrian; Vilmann, Peter; Gorunescu, Florin; Janssen, Jan; Hocke, Michael; Larsen, Michael; Iglesias-Garcia, Julio; Arcidiacono, Paolo; Will, Uwe; Giovannini, Marc; Dietrich, Cristoph F; Havre, Roald; Gheorghe, Cristian; McKay, Colin; Gheonea, Dan Ionuţ; Ciurea, Tudorel

2012-01-01

By using strain assessment, real-time endoscopic ultrasound (EUS) elastography provides additional information about a lesion's characteristics in the pancreas. We assessed the accuracy of real-time EUS elastography in focal pancreatic lesions using computer-aided diagnosis by artificial neural network analysis. We performed a prospective, blinded, multicentric study at of 258 patients (774 recordings from EUS elastography) who were diagnosed with chronic pancreatitis (n = 47) or pancreatic adenocarcinoma (n = 211) from 13 tertiary academic medical centers in Europe (the European EUS Elastography Multicentric Study Group). We used postprocessing software analysis to compute individual frames of elastography movies recorded by retrieving hue histogram data from a dynamic sequence of EUS elastography into a numeric matrix. The data then were analyzed in an extended neural network analysis, to automatically differentiate benign from malignant patterns. The neural computing approach had 91.14% training accuracy (95% confidence interval [CI], 89.87%-92.42%) and 84.27% testing accuracy (95% CI, 83.09%-85.44%). These results were obtained using the 10-fold cross-validation technique. The statistical analysis of the classification process showed a sensitivity of 87.59%, a specificity of 82.94%, a positive predictive value of 96.25%, and a negative predictive value of 57.22%. Moreover, the corresponding area under the receiver operating characteristic curve was 0.94 (95% CI, 0.91%-0.97%), which was significantly higher than the values obtained by simple mean hue histogram analysis, for which the area under the receiver operating characteristic was 0.85. Use of the artificial intelligence methodology via artificial neural networks supports the medical decision process, providing fast and accurate diagnoses. Copyright © 2012 AGA Institute. Published by Elsevier Inc. All rights reserved.

Radiation-induced genetic instability: no association with changes in radiosensitivity or cell cycle checkpoints in C3H 10T1/2 mouse fibroblasts

International Nuclear Information System (INIS)

Crompton, N.E.A.; Emery, G.C.; Shi Yuquan; Sigg, M.; Blattmann, H.

1998-01-01

We investigated various phenotypic characteristics of radiation-induced morphologically transformed C3H 10T1/2 mouse fibroblasts. The cells were treated with 8 Gy x-rays, and type II/III foci were isolated. Cell lines were developed from these foci, and subsequently clones were established from these focal lines. The clones were examined for DNA content, radiosensitivity and inducible cell cycle arrests. Besides the morphological changes associated with the transformed state, the major difference between the isolated focal lines or derived clones and the parental C3H 10T1/2 line was one of ploidy. The transformed cells often displayed aneuploid and multiple polyploid populations. No change in the radiosensitivity of the transformed cells was observed. Furthermore, the two major radiation- and staurosporine-induced G1 and G2 cell cycle arrests observed in the parental cell line were also observed in the morphological transformants, suggesting that checkpoint function was normal. (orig.)

Rac function is crucial for cell migration but is not required for spreading and focal adhesion formation

DEFF Research Database (Denmark)

Steffen, Anika; Ladwein, Markus; Dimchev, Georgi A

2013-01-01

can be potently stimulated by Rho GTPases of the Rac subfamily, but also by RhoG or Cdc42. Here we describe viable fibroblast cell lines genetically deficient for Rac1 that lack detectable levels of Rac2 and Rac3. Rac-deficient cells were devoid of apparent lamellipodia, but these structures were...... filopodia and established focal adhesions. Spreading in these cells was achieved by the extension of filopodia followed by the advancement of cytoplasmic veils between them. The number and size of focal adhesions as well as their intensity were largely unaffected by genetic removal of Rac1. However, Rac...

Artificial cell mimics as simplified models for the study of cell biology.

Science.gov (United States)

Salehi-Reyhani, Ali; Ces, Oscar; Elani, Yuval

2017-07-01

Living cells are hugely complex chemical systems composed of a milieu of distinct chemical species (including DNA, proteins, lipids, and metabolites) interconnected with one another through a vast web of interactions: this complexity renders the study of cell biology in a quantitative and systematic manner a difficult task. There has been an increasing drive towards the utilization of artificial cells as cell mimics to alleviate this, a development that has been aided by recent advances in artificial cell construction. Cell mimics are simplified cell-like structures, composed from the bottom-up with precisely defined and tunable compositions. They allow specific facets of cell biology to be studied in isolation, in a simplified environment where control of variables can be achieved without interference from a living and responsive cell. This mini-review outlines the core principles of this approach and surveys recent key investigations that use cell mimics to address a wide range of biological questions. It will also place the field in the context of emerging trends, discuss the associated limitations, and outline future directions of the field. Impact statement Recent years have seen an increasing drive to construct cell mimics and use them as simplified experimental models to replicate and understand biological phenomena in a well-defined and controlled system. By summarizing the advances in this burgeoning field, and using case studies as a basis for discussion on the limitations and future directions of this approach, it is hoped that this minireview will spur others in the experimental biology community to use artificial cells as simplified models with which to probe biological systems.

Dual-layer electrode-driven liquid crystal lens with electrically tunable focal length and focal plane

Science.gov (United States)

Zhang, Y. A.; Lin, C. F.; Lin, J. P.; Zeng, X. Y.; Yan, Q.; Zhou, X. T.; Guo, T. L.

2018-04-01

Electric-field-driven liquid crystal (ELC) lens with tunable focal length and their depth of field has been extensively applied in 3D display and imaging systems. In this work, a dual-layer electrode-driven liquid crystal (DELC) lens with electrically tunable focal length and controllable focal plane is demonstrated. ITO-SiO2-AZO electrodes with the dual-layer staggered structure on the top substrate are used as driven electrodes within a LC cell, which permits the establishment of an alternative controllability. The focal length of the DELC lens can be adjusted from 1.41 cm to 0.29 cm when the operating voltage changes from 15 V to 40 V. Furthermore, the focal plane of the DELC lens can selectively move by changing the driving method of the applied voltage to the next driven electrodes. This work demonstrates that the DELC lens has potential applications in imaging systems because of electrically tunable focal length and controllable focal plane.

Chimeric Antigen Receptor- and TCR-Modified T Cells Enter Main Street and Wall Street.

Science.gov (United States)

Barrett, David M; Grupp, Stephan A; June, Carl H

2015-08-01

The field of adoptive cell transfer (ACT) is currently comprised of chimeric Ag receptor (CAR)- and TCR-engineered T cells and has emerged from principles of basic immunology to paradigm-shifting clinical immunotherapy. ACT of T cells engineered to express artificial receptors that target cells of choice is an exciting new approach for cancer, and it holds equal promise for chronic infection and autoimmunity. Using principles of synthetic biology, advances in immunology, and genetic engineering have made it possible to generate human T cells that display desired specificities and enhanced functionalities. Clinical trials in patients with advanced B cell leukemias and lymphomas treated with CD19-specific CAR T cells have induced durable remissions in adults and children. The prospects for the widespread availability of engineered T cells have changed dramatically given the recent entry of the pharmaceutical industry to this arena. In this overview, we discuss some of the challenges and opportunities that face the field of ACT. Copyright © 2015 by The American Association of Immunologists, Inc.

Heterogeneity of Focal Adhesions and Focal Contacts in Motile Fibroblasts.

Science.gov (United States)

Gladkikh, Aleena; Kovaleva, Anastasia; Tvorogova, Anna; Vorobjev, Ivan A

2018-01-01

Cell-extracellular matrix (ECM) adhesion is an important property of virtually all cells in multicellular organisms. Cell-ECM adhesion studies, therefore, are very significant both for biology and medicine. Over the last three decades, biomedical studies resulted in a tremendous advance in our understanding of the molecular basis and functions of cell-ECM adhesion. Based on morphological and molecular criteria, several different types of model cell-ECM adhesion structures including focal adhesions, focal complexes, fibrillar adhesions, podosomes, and three-dimensional matrix adhesions have been described. All the subcellular structures that mediate cell-ECM adhesion are quite heterogeneous, often varying in size, shape, distribution, dynamics, and, to a certain extent, molecular constituents. The morphological "plasticity" of cell-ECM adhesion perhaps reflects the needs of cells to sense, adapt, and respond to a variety of extracellular environments. In addition, cell type (e.g., differentiation status, oncogenic transformation, etc.) often exerts marked influence on the structure of cell-ECM adhesions. Although molecular, genetic, biochemical, and structural studies provide important maps or "snapshots" of cell-ECM adhesions, the area of research that is equally valuable is to study the heterogeneity of FA subpopulations within cells. Recently time-lapse observations on the FA dynamics become feasible, and behavior of individual FA gives additional information on cell-ECM interactions. Here we describe a robust method of labeling of FA using plasmids with fluorescent markers for paxillin and vinculin and quantifying the morphological and dynamical parameters of FA.

Bioengineering of Artificial Antigen Presenting Cells and Lymphoid Organs.

Science.gov (United States)

Wang, Chao; Sun, Wujin; Ye, Yanqi; Bomba, Hunter N; Gu, Zhen

2017-01-01

The immune system protects the body against a wide range of infectious diseases and cancer by leveraging the efficiency of immune cells and lymphoid organs. Over the past decade, immune cell/organ therapies based on the manipulation, infusion, and implantation of autologous or allogeneic immune cells/organs into patients have been widely tested and have made great progress in clinical applications. Despite these advances, therapy with natural immune cells or lymphoid organs is relatively expensive and time-consuming. Alternatively, biomimetic materials and strategies have been applied to develop artificial immune cells and lymphoid organs, which have attracted considerable attentions. In this review, we survey the latest studies on engineering biomimetic materials for immunotherapy, focusing on the perspectives of bioengineering artificial antigen presenting cells and lymphoid organs. The opportunities and challenges of this field are also discussed.

Invariant Natural Killer T Cell Agonist Modulates Experimental Focal and Segmental Glomerulosclerosis

Science.gov (United States)

Semedo, Patricia; Buscariollo, Bruna N.; Donizetti-Oliveira, Cassiano; Cenedeze, Marcos A.; Soares, Maria Fernanda; Pacheco-Silva, Alvaro; Savage, Paul B.; Câmara, Niels O. S.; Keller, Alexandre C.

2012-01-01

A growing body of evidence demonstrates a correlation between Th2 cytokines and the development of focal and segmental glomerulosclerosis (FSGS). Therefore, we hypothesized that GSL-1, a monoglycosylceramide from Sphingomonas ssp. with pro-Th1 activity on invariant Natural Killer T (iNKT) lymphocytes, could counterbalance the Th2 profile and modulate glomerulosclerosis. Using an adriamycin(ADM)-based model of FSGS, we found that BALB/c mice presented albuminuria and glomerular degeneration in association with a Th2-like pro-fibrogenic profile; these mice also expressed a combination of inflammatory cytokines, such as IL-4, IL-1α, IL-1β, IL-17, TNF-α, and chemokines, such as RANTES and eotaxin. In addition, we observed a decrease in the mRNA levels of GD3 synthase, the enzyme responsible for GD3 metabolism, a glycolipid associated with podocyte physiology. GSL-1 treatment inhibited ADM-induced renal dysfunction and preserved kidney architecture, a phenomenon associated with the induction of a Th1-like response, increased levels of GD3 synthase transcripts and inhibition of pro-fibrotic transcripts and inflammatory cytokines. TGF-β analysis revealed increased levels of circulating protein and tissue transcripts in both ADM- and GSL-1-treated mice, suggesting that TGF-β could be associated with both FSGS pathology and iNKT-mediated immunosuppression; therefore, we analyzed the kidney expression of phosphorylated SMAD2/3 and SMAD7 proteins, molecules associated with the deleterious and protective effects of TGF-β, respectively. We found high levels of phosphoSMAD2/3 in ADM mice in contrast to the GSL-1 treated group in which SMAD7 expression increased. These data suggest that GSL-1 treatment modulates the downstream signaling of TGF-β through a renoprotective pathway. Finally, GSL-1 treatment at day 4, a period when proteinuria was already established, was still able to improve renal function, preserve renal structure and inhibit fibrogenic transcripts. In

Renal cell carcinoma with t(6,11: A case report and review of literature

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K S Jansi Prema

2017-01-01

Full Text Available Renal cell carcinomas (RCCs with t(6,11 are very rare tumours. Only a few cases have been reported so far. t(6,11 results in fusion of alpha gene and transcription factor EB (TFEB gene resulting in the overexpression of TFEB. The specific light and immunohistochemical features help in the diagnosis of this rare type of tumor. We report a case of t(6,11 RCC in a 38-year-old female who was incidentally found to have a right renal mass. We present this case to emphasize the typical light microscopic picture of this extremely rare tumor. Two population of cells are seen: larger cells with abundant cytoplasm and smaller cells with scant cytoplasm. Smaller cells are arranged around hyaline nodules resulting in the formation of characteristic pseudorosettes. Immunohistochemically, these tumors are diffusely positive for vimentin and focally positive for HMB 45 and CD 117. Knowledge about the typical biphasic light microscopic appearance and the characteristic immunohistochemical features help in the diagnosis of this rare type of translocation associated RCC.

Natural - synthetic - artificial!

DEFF Research Database (Denmark)

Nielsen, Peter E

2010-01-01

The terms "natural," "synthetic" and "artificial" are discussed in relation to synthetic and artificial chromosomes and genomes, synthetic and artificial cells and artificial life.......The terms "natural," "synthetic" and "artificial" are discussed in relation to synthetic and artificial chromosomes and genomes, synthetic and artificial cells and artificial life....

Meningeal mast cell-T cell crosstalk regulates T cell encephalitogenicity.

Science.gov (United States)

Russi, Abigail E; Walker-Caulfield, Margaret E; Guo, Yong; Lucchinetti, Claudia F; Brown, Melissa A

2016-09-01

GM-CSF is a cytokine produced by T helper (Th) cells that plays an essential role in orchestrating neuroinflammation in experimental autoimmune encephalomyelitis, a rodent model of multiple sclerosis. Yet where and how Th cells acquire GM-CSF expression is unknown. In this study we identify mast cells in the meninges, tripartite tissues surrounding the brain and spinal cord, as important contributors to antigen-specific Th cell accumulation and GM-CSF expression. In the absence of mast cells, Th cells do not accumulate in the meninges nor produce GM-CSF. Mast cell-T cell co-culture experiments and selective mast cell reconstitution of the meninges of mast cell-deficient mice reveal that resident meningeal mast cells are an early source of caspase-1-dependent IL-1β that licenses Th cells to produce GM-CSF and become encephalitogenic. We also provide evidence of mast cell-T cell co-localization in the meninges and CNS of recently diagnosed acute MS patients indicating similar interactions may occur in human demyelinating disease. Copyright © 2016 Elsevier Ltd. All rights reserved.

Application of Artificial Bee Colony in Model Parameter Identification of Solar Cells

Directory of Open Access Journals (Sweden)

Rongjie Wang

2015-07-01

Full Text Available The identification of values of solar cell parameters is of great interest for evaluating solar cell performances. The algorithm of an artificial bee colony was used to extract model parameters of solar cells from current-voltage characteristics. Firstly, the best-so-for mechanism was introduced to the original artificial bee colony. Then, a method was proposed to identify parameters for a single diode model and double diode model using this improved artificial bee colony. Experimental results clearly demonstrate the effectiveness of the proposed method and its superior performance compared to other competing methods.

MRI of focal liver lesions using a 1.5T turbo-spinecho technique compared with spinecho technique

International Nuclear Information System (INIS)

Steiner, S.; Vogl, T.J.; Fischer, P.; Steger, W.; Neuhaus, P.; Keck, H.

1995-01-01

In our study 35 patients with suspected focal liver lesions were examined. Standardised imaging protocol included a conventional T 2 -weighted SE sequence (T R /T E = 2000/90/45, acquisition time = 10.20) as well as a T 2 -weighted TSE sequence (T R /T E = 4700/90, acquisition time = 6.33). Calculation of S/N and C/N ratio as a basis of quantitative evaluation was done using standard methods. A diagnostic score was implemented to enable qualitative assessment. In 7% (n=2) the TSE sequence enabled detection of further liver lesions showing a size of less than 1 cm in diameter. Comparing anatomical details the TSE sequence was superior. S/N and C/N ratio of anatomic and pathologic structures of the TSE sequence were higher compared to results of the SE sequence. (orig./MG) [de

Clonación artificial de controladores basados en técnicas de inteligencia artificial

OpenAIRE

Javier Antonio Ballesteros; Alonso Guevara

2004-01-01

En el presente articulo se expone un avance de anteproyecto, sobre técnicas de inteligencia Artificial, su aplicación a procesos industriales y herramientas para realizar simulación. Se citan algunos trabajos en los cuales hay resultados, y que prestan un soporte lógico para continuar con el desarrollo del proyecto. Ademas, se analiza, la función que cumple el controlador el cual debe ser preciso, confiable y que a su vez reduzca costos. Por estas razones se tomó como base del proyecto un con...

Fibronectin-tethered graphene oxide as an artificial matrix for osteogenesis

International Nuclear Information System (INIS)

Subbiah, Ramesh; Du, Ping; Van, Se Young; Suhaeri, Muhammad; Lee, Kangwon; Park, Kwideok; Hwang, Mintai P

2014-01-01

An artificial matrix (Fn-Tigra), consisting of graphene oxide (GO) and fibronectin (Fn), is developed on pure titanium (Ti) substrates via an electrodropping technique assisted with a custom-made coaxial needle. The morphology and topography of the resulting artificial matrix is orderly aligned and composed of porous microcavities. In addition, Fn is homogenously distributed and firmly bound onto GO as determined via immunofluorescence and elemental mapping, respectively. The artificial matrix is moderately hydrophobic (63.7°), and exhibits an average roughness of 546 nm and a Young’s modulus (E) of approximately 4.8 GPa. The biocompatibility, cellular behavior, and osteogenic potential of preosteoblasts on Fn-Tigra are compared to those of cells cultured on Ti and Ti-GO (Tigra). Cell proliferation and viability are significantly higher on Fn-Tigra and Tigra than that of cells grown on Ti. Focal adhesion molecule (vinculin) expression is highly activated at the central and peripheral area of preosteoblasts when cultured on Fn-Tigra. Furthermore, we demonstrate enhanced in vitro osteogenic differentiation of preosteoblasts cultured on Fn-Tigra over those cultured on bare Ti, as determined via Alizarin red and von Kossa staining, and the analysis of osteocalcin, type I collagen, alkaline phosphatase activity, and calcium contents. Finally, we investigate the biophysical and biomechanical properties of the cells using AFM. While the height and roughness of preosteoblasts increased with time, cell surface area decreased during in vitro osteogenesis over 2 weeks. In addition, the E of cells cultured on Tigra and Fn-Tigra increase in a statistically significant and time-dependent manner by 30%, while those cultured on bare Ti retain a relatively consistent E. In summary, we engineer a biocompatible artificial matrix (Fn-Tigra) capable of osteogenic induction and consequently demonstrate its potential in bone tissue engineering applications. (paper)

Fibronectin-tethered graphene oxide as an artificial matrix for osteogenesis.

Science.gov (United States)

Subbiah, Ramesh; Du, Ping; Van, Se Young; Suhaeri, Muhammad; Hwang, Mintai P; Lee, Kangwon; Park, Kwideok

2014-10-20

An artificial matrix (Fn-Tigra), consisting of graphene oxide (GO) and fibronectin (Fn), is developed on pure titanium (Ti) substrates via an electrodropping technique assisted with a custom-made coaxial needle. The morphology and topography of the resulting artificial matrix is orderly aligned and composed of porous microcavities. In addition, Fn is homogenously distributed and firmly bound onto GO as determined via immunofluorescence and elemental mapping, respectively. The artificial matrix is moderately hydrophobic (63.7°), and exhibits an average roughness of 546 nm and a Young's modulus (E) of approximately 4.8 GPa. The biocompatibility, cellular behavior, and osteogenic potential of preosteoblasts on Fn-Tigra are compared to those of cells cultured on Ti and Ti-GO (Tigra). Cell proliferation and viability are significantly higher on Fn-Tigra and Tigra than that of cells grown on Ti. Focal adhesion molecule (vinculin) expression is highly activated at the central and peripheral area of preosteoblasts when cultured on Fn-Tigra. Furthermore, we demonstrate enhanced in vitro osteogenic differentiation of preosteoblasts cultured on Fn-Tigra over those cultured on bare Ti, as determined via Alizarin red and von Kossa staining, and the analysis of osteocalcin, type I collagen, alkaline phosphatase activity, and calcium contents. Finally, we investigate the biophysical and biomechanical properties of the cells using AFM. While the height and roughness of preosteoblasts increased with time, cell surface area decreased during in vitro osteogenesis over 2 weeks. In addition, the E of cells cultured on Tigra and Fn-Tigra increase in a statistically significant and time-dependent manner by 30%, while those cultured on bare Ti retain a relatively consistent E. In summary, we engineer a biocompatible artificial matrix (Fn-Tigra) capable of osteogenic induction and consequently demonstrate its potential in bone tissue engineering applications.

Changing T cell specificity by retroviral T cell receptor display

NARCIS (Netherlands)

Kessels, H. W.; van den Boom, M. D.; Spits, H.; Hooijberg, E.; Schumacher, T. N.

2000-01-01

The diversity of the T cell receptor (TCR) repertoire is limited, because of the processes of positive and negative T cell selection. To obtain T cells with specificities beyond the immune system's capacity, we have developed a strategy for retroviral TCR display. In this approach, a library of T

Resveratrol Regulates Colorectal Cancer Cell Invasion by Modulation of Focal Adhesion Molecules.

Science.gov (United States)

Buhrmann, Constanze; Shayan, Parviz; Goel, Ajay; Shakibaei, Mehdi

2017-09-27

Resveratrol, a safe and multi-targeted agent, has been associated with suppression of survival, proliferation and metastasis of cancer, however, the underlying mechanisms for its anti-cancer activity, particularly on cellular signaling during cancer cell migration still remain poorly understood. We investigated the invasion response of two human colorectal cancer (CRC) cells (HCT116 and SW480) to resveratrol and studied the effect of specific pharmacological inhibitors, cytochalasin D (CytD) and focal adhesion kinase-inhibitor (FAK-I) on FAK, cell viability and migration in CRC. We found that resveratrol altered cell phenotype of both CRC cells, reduced cell viability and the results were comparable to FAK-I and CytD. These effects of resveratrol were associated with marked Sirt1 up-regulation, FAK down-regulation, inhibition of focal adhesion and potentiation of effects by combinatorial treatment of resveratrol and inhibitors. Interestingly, inhibition of FAK with FAK-I or treatment with CytD suppressed resveratrol-induced Sirt1 up-regulation and markedly down-regulated FAK expression. Resveratrol or combination treatment with inhibitors significantly activated caspase-3 and potentiated apoptosis. Moreover, resveratrol suppressed invasion and colony forming capacity, cell proliferation, β1-Integrin expression and activation of FAK of cells in alginate tumor microenvironment, similar to FAK-I or CytD. Finally, we demonstrated that resveratrol, FAK-I or CytD inhibited activation of NF-κB, suppressed NF-κB-dependent gene end-products involved in invasion, metastasis, and apoptosis; and these effects of resveratrol were potentiated by combination treatment with FAK-I or CytD. Our data illustrated that the anti-invasion effect of resveratrol by inhibition of FAK activity has a potential beneficial role in disease prevention and therapeutic management of CRC.

T-cell help permits memory CD8(+) T-cell inflation during cytomegalovirus latency.

Science.gov (United States)

Walton, Senta M; Torti, Nicole; Mandaric, Sanja; Oxenius, Annette

2011-08-01

CD4(+) T cells are implied to sustain CD8(+) T-cell responses during persistent infections. As CD4(+) T cells are often themselves antiviral effectors, they might shape CD8(+) T-cell responses via help or via controlling antigen load. We used persistent murine CMV (MCMV) infection to dissect the impact of CD4(+) T cells on virus-specific CD8(+) T cells, distinguishing between increased viral load in the absence of CD4(+) T cells and CD4(+) T-cell-mediated helper mechanisms. Absence of T-helper cells was associated with sustained lytic MCMV replication and led to a slow and gradual reduction of the size and function of the MCMV-specific CD8(+) T-cell pool. However, when virus replication was controlled in the absence of CD4(+) T cells, CD8(+) T-cell function was comparably impaired, but in addition CD8(+) T-cell inflation, a hallmark of CMV infection, was completely abolished. Thus, CD8(+) T-cell inflation during latent CMV infection is strongly dependent on CD4(+) T-cell helper functions, which can partially be compensated by ongoing lytic viral replication in the absence of CD4(+) T cells. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Focal myositis: A review.

Science.gov (United States)

Devic, P; Gallay, L; Streichenberger, N; Petiot, P

2016-11-01

Amongst the heterogeneous group of inflammatory myopathies, focal myositis stands as a rare and benign dysimmune disease. Although it can be associated with root and/or nerve lesions, traumatic muscle lesions and autoimmune diseases, its triggering factors remain poorly understood. Defined as an isolated inflammatory pseudotumour usually restricted to one skeletal muscle, clinical presentation of focal myositis is that of a rapidly growing solitary mass within a single muscle, usually in the lower limbs. Electromyography shows spontaneous activity associated with a myopathic pattern. MRI reveals a contrast enhanced enlarged muscle appearing hyper-intense on FAT-SAT T2 weighted images. Adjacent structures are spared and there are no calcifications. Serum creatine kinase (CK) levels are usually moderately augmented and biological markers of systemic inflammation are absent in most cases. Pathological histological features include marked variation in fibre size, inflammatory infiltrates mostly composed of T CD4+ lymphocytes and macrophages, degenerating/regenerating fibres and interstitial fibrosis. Differential diagnoses are numerous and include myositis of other origin with focal onset. Steroid treatment should be reserved for patients who present with major pain, nerve lesions, associated autoimmune disease, or elevated C reactive protein or CK. Copyright © 2016 Elsevier B.V. All rights reserved.

Cell nanomechanics and focal adhesions are regulated by retinol and conjugated linoleic acid in a dose-dependent manner

International Nuclear Information System (INIS)

Silberberg, Yaron R; Horton, Michael A; Pelling, Andrew E; Yakubov, Gleb E

2009-01-01

Retinol and conjugated linoleic acid (CLA) have previously been shown to have an important role in gene expression and various cellular processes, including differentiation, proliferation and cell death. In this study we have investigated the effect of retinol and CLA, both individually and in combination, on the intracellular cytoskeleton, focal adhesions (FAs) and the nanomechanical properties of 3T3 fibroblasts. We observed a dose-dependent decrease in the formation of FAs following treatment with either compound, which was directly correlated to an increase in cell height (>30%) and a decrease in the measured Young's modulus (∼28%). Furthermore, treatments with both compounds demonstrated an increased effect and led to a reduction of>70% in the average number of FAs per cell and a decrease of >50% in average cell stiffness. These data reveal that retinol and CLA disrupt FA formation, leading to an increase in cell height and a significant decrease in stiffness. These results may broaden our understanding of the interplay between cell nanomechanics and cellular contact with the external microenvironment, and help to shed light on the important role of retinoids and CLA in health and disease.

Pharmacologic suppression of target cell recognition by engineered T cells expressing chimeric T-cell receptors.

Science.gov (United States)

Alvarez-Vallina, L; Yañez, R; Blanco, B; Gil, M; Russell, S J

2000-04-01

Adoptive therapy with autologous T cells expressing chimeric T-cell receptors (chTCRs) is of potential interest for the treatment of malignancy. To limit possible T-cell-mediated damage to normal tissues that weakly express the targeted tumor antigen (Ag), we have tested a strategy for the suppression of target cell recognition by engineered T cells. Jurkat T cells were transduced with an anti-hapten chTCR tinder the control of a tetracycline-suppressible promoter and were shown to respond to Ag-positive (hapten-coated) but not to Ag-negative target cells. The engineered T cells were then reacted with hapten-coated target cells at different effector to target cell ratios before and after exposure to tetracycline. When the engineered T cells were treated with tetracycline, expression of the chTCR was greatly decreased and recognition of the hapten-coated target cells was completely suppressed. Tetracycline-mediated suppression of target cell recognition by engineered T cells may be a useful strategy to limit the toxicity of the approach to cancer gene therapy.

Improved k-t PCA Algorithm Using Artificial Sparsity in Dynamic MRI.

Science.gov (United States)

Wang, Yiran; Chen, Zhifeng; Wang, Jing; Yuan, Lixia; Xia, Ling; Liu, Feng

2017-01-01

The k - t principal component analysis ( k - t PCA) is an effective approach for high spatiotemporal resolution dynamic magnetic resonance (MR) imaging. However, it suffers from larger residual aliasing artifacts and noise amplification when the reduction factor goes higher. To further enhance the performance of this technique, we propose a new method called sparse k - t PCA that combines the k - t PCA algorithm with an artificial sparsity constraint. It is a self-calibrated procedure that is based on the traditional k - t PCA method by further eliminating the reconstruction error derived from complex subtraction of the sampled k - t space from the original reconstructed k - t space. The proposed method is tested through both simulations and in vivo datasets with different reduction factors. Compared to the standard k - t PCA algorithm, the sparse k - t PCA can improve the normalized root-mean-square error performance and the accuracy of temporal resolution. It is thus useful for rapid dynamic MR imaging.

Artificial Neural Network Based Model of Photovoltaic Cell

Directory of Open Access Journals (Sweden)

Messaouda Azzouzi

2017-03-01

Full Text Available This work concerns the modeling of a photovoltaic system and the prediction of the sensitivity of electrical parameters (current, power of the six types of photovoltaic cells based on voltage applied between terminals using one of the best known artificial intelligence technique which is the Artificial Neural Networks. The results of the modeling and prediction have been well shown as a function of number of iterations and using different learning algorithms to obtain the best results. 

A Multicentric T-Cell Lymphoma with a Plasmacytoid Morphology in a Dog

Directory of Open Access Journals (Sweden)

Alissa Bally

2018-01-01

Full Text Available An 8-year-old male (neutered Labrador with a history of erythematous skin lesions and exercise intolerance for a prolonged period was suddenly found dead. Necropsy findings revealed an infiltrative, focally extensive mass which occupied 25% of the cardiac interventricular septum. Severe endocardiosis was also found on the bicuspid and tricuspid valves. The submandibular lymph nodes and kidneys were bilaterally enlarged, and the pre-hepatic lymph node and spleen were also enlarged. Multiple dermal pustules were present around the mouth and on the ear, and small ulcers were present on the tongue. Histopathological examination detected the presence of neoplastic lymphocytes with a plasmacytoid morphology in these tissues as well as in the tongue and skin lesions. Immunohistochemical (CD3+/CD18+ evaluation was consistent with a T-cell lymphoma, which could be classified as a peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS.

Imaging TCR-Dependent NFAT-Mediated T-Cell Activation with Positron Emission Tomography In Vivo

Directory of Open Access Journals (Sweden)

Vladimir Ponomarev

2001-01-01

Full Text Available A noninvasive method for molecular imaging of T-cell activity in vivo would be of considerable value. It would aid in understanding the role of specific genes and signal transduction pathways in the course of normal and pathologic immune responses, could elucidate temporal dynamics and immune regulation at different stages of disease and following therapy. We developed and assessed a novel method for monitoring the T-cell receptor (TCR -dependent nuclear factor of activated T cells (NFAT -mediated activation of T cells by optical fluorescence imaging (OFI and positron emission tomography (PET. The herpes simplex virus type 1 thymidine kinase/green fluorescent protein [HSV1-tk/GFP (TKGFP ] dual reporter gene was used to monitor NFAT-mediated transcriptional activation in human Jurkat cells. A recombinant retrovirus bearing the NFAT-TKGFP reporter system was constructed in which the TKGFP reporter gene was placed under control of an artificial cis-acting NFAT-specific enhancer. Transduced Jurkat cells were used to establish subcutaneous infiltrates in nude rats. We demonstrated that noninvasive OR and nuclear imaging of T-cell activation is feasible using the NFAT-TKGFP reporter system. PET imaging with [124]FIAU using the NFAT-TKGFP reporter system is sufficiently sensitive to detect T-cell activation in vivo. PET images were confirmed by independent measurements of T-cell activation (e.g., CD69 and induction of GFP fluorescence. PET imaging of TCR-induced NFAT-dependent transcriptional activity may be useful in the assessment of T cell responses, T-cell-based adoptive therapies, vaccination strategies and immunosuppressive drugs.

Neural network control of focal position during time-lapse microscopy of cells.

Science.gov (United States)

Wei, Ling; Roberts, Elijah

2018-05-09

Live-cell microscopy is quickly becoming an indispensable technique for studying the dynamics of cellular processes. Maintaining the specimen in focus during image acquisition is crucial for high-throughput applications, especially for long experiments or when a large sample is being continuously scanned. Automated focus control methods are often expensive, imperfect, or ill-adapted to a specific application and are a bottleneck for widespread adoption of high-throughput, live-cell imaging. Here, we demonstrate a neural network approach for automatically maintaining focus during bright-field microscopy. Z-stacks of yeast cells growing in a microfluidic device were collected and used to train a convolutional neural network to classify images according to their z-position. We studied the effect on prediction accuracy of the various hyperparameters of the neural network, including downsampling, batch size, and z-bin resolution. The network was able to predict the z-position of an image with ±1 μm accuracy, outperforming human annotators. Finally, we used our neural network to control microscope focus in real-time during a 24 hour growth experiment. The method robustly maintained the correct focal position compensating for 40 μm of focal drift and was insensitive to changes in the field of view. About ~100 annotated z-stacks were required to train the network making our method quite practical for custom autofocus applications.

T-cell receptor transfer into human T cells with ecotropic retroviral vectors.

Science.gov (United States)

Koste, L; Beissert, T; Hoff, H; Pretsch, L; Türeci, Ö; Sahin, U

2014-05-01

Adoptive T-cell transfer for cancer immunotherapy requires genetic modification of T cells with recombinant T-cell receptors (TCRs). Amphotropic retroviral vectors (RVs) used for TCR transduction for this purpose are considered safe in principle. Despite this, TCR-coding and packaging vectors could theoretically recombine to produce replication competent vectors (RCVs), and transduced T-cell preparations must be proven free of RCV. To eliminate the need for RCV testing, we transduced human T cells with ecotropic RVs so potential RCV would be non-infectious for human cells. We show that transfection of synthetic messenger RNA encoding murine cationic amino-acid transporter 1 (mCAT-1), the receptor for murine retroviruses, enables efficient transient ecotropic transduction of human T cells. mCAT-1-dependent transduction was more efficient than amphotropic transduction performed in parallel, and preferentially targeted naive T cells. Moreover, we demonstrate that ecotropic TCR transduction results in antigen-specific restimulation of primary human T cells. Thus, ecotropic RVs represent a versatile, safe and potent tool to prepare T cells for the adoptive transfer.

Selection and characterization of T-cell variants lacking molecules involved in T-cell activation (T3 T-cell receptor, T44, and T11): analysis of the functional relationship among different pathways of activation

International Nuclear Information System (INIS)

Moretta, A.; Poggi, A.; Olive, D.; Bottino, C.; Fortis, C.; Pantaleo, G.; Moretta, L.

1987-01-01

A clone of the interleukin 2-producing Jurkat leukemia cell line termed JA3 (surface phenotype, T3 + , Ti + , T44 + , T11 + , T40 + ) has been used to induce and select cell variants lacking surface molecules involved in T-cell activation. Following 200 rad of γ-radiation (1 rad = 0.01 Gy), cells were treated with monoclonal antibodies (mAbs) directed to T3, Ti, T44, or T11 antigen and complement. After growth of the residual cells in culture, negative cells were cloned under limiting conditions. Depending on the specificity of the mAb used for the immunoselection, three groups of variants were obtained. (i) The use of mAbs directed to T3 or Ti resulted in cell variants that expressed the T3 - Ti - T44 + Leu1 + T11 + T40 + 4F2 + HLA class I + surface phenotype. (ii) Immunoselection with anti-T44 mAb resulted in 2 variants that shared the T3 - Ti - T44 - Leu1 - T11 - T40 - 4F2 - HLA class I + phenotype. (iii) Cell treatment with anti-T11 mAb resulted in 15 variants characterized by the lack of T11 antigen expression and of all the other T-cell-specific surface antigens. Therefore, it appears that the different sets of JA3 cell variants, like T cells at discrete stages of intrathymic differentiation, may follow a coordinated expression of surface differentiation antigens. Analysis of the functional responsiveness of the three distinct groups of JA3 cell variants to different stimuli showed that all produced interleukin 2 in response to A23187 calcium ionophore plus phorbol 12-myristate 13-acetate

FOXO3 regulates CD8 T cell memory by T cell-intrinsic mechanisms.

Directory of Open Access Journals (Sweden)

Jeremy A Sullivan

2012-02-01

Full Text Available CD8 T cell responses have three phases: expansion, contraction, and memory. Dynamic alterations in proliferation and apoptotic rates control CD8 T cell numbers at each phase, which in turn dictate the magnitude of CD8 T cell memory. Identification of signaling pathways that control CD8 T cell memory is incomplete. The PI3K/Akt signaling pathway controls cell growth in many cell types by modulating the activity of FOXO transcription factors. But the role of FOXOs in regulating CD8 T cell memory remains unknown. We show that phosphorylation of Akt, FOXO and mTOR in CD8 T cells occurs in a dynamic fashion in vivo during an acute viral infection. To elucidate the potentially dynamic role for FOXO3 in regulating homeostasis of activated CD8 T cells in lymphoid and non-lymphoid organs, we infected global and T cell-specific FOXO3-deficient mice with Lymphocytic Choriomeningitis Virus (LCMV. We found that FOXO3 deficiency induced a marked increase in the expansion of effector CD8 T cells, preferentially in the spleen, by T cell-intrinsic mechanisms. Mechanistically, the enhanced accumulation of proliferating CD8 T cells in FOXO3-deficient mice was not attributed to an augmented rate of cell division, but instead was linked to a reduction in cellular apoptosis. These data suggested that FOXO3 might inhibit accumulation of growth factor-deprived proliferating CD8 T cells by reducing their viability. By virtue of greater accumulation of memory precursor effector cells during expansion, the numbers of memory CD8 T cells were strikingly increased in the spleens of both global and T cell-specific FOXO3-deficient mice. The augmented CD8 T cell memory was durable, and FOXO3 deficiency did not perturb any of the qualitative attributes of memory T cells. In summary, we have identified FOXO3 as a critical regulator of CD8 T cell memory, and therapeutic modulation of FOXO3 might enhance vaccine-induced protective immunity against intracellular pathogens.

Focal status epilepticus: follow-up by perfusion- and diffusion MRI

International Nuclear Information System (INIS)

El-Koussy, M.; Loevblad, K.O.; Kiefer, C.; Schroth, G.; Mathis, J.; Stepper, F.

2002-01-01

Diffusion-weighted MRI demonstrated bright right temporoparietal cortex, right hippocampus, and left cerebellum in a 63-year-old female suffering a focal convulsive status epilepticus. Hyperperfusion was noted in the right temporoparietal region. Two days later, a tendency to normalization of most of the diffusion and perfusion changes was noted, apart from the right hippocampus which became brighter on diffusion- and T2-weighted images. On the tenth day the apparent diffusion coefficient was slightly elevated, getting brighter on T2-weighted images with suspected mild post-contrast enhancement. We postulate that the discharging right hippocampus suffered cytotoxic edema, which later progressed to cell damage. (orig.)

Focal status epilepticus: follow-up by perfusion- and diffusion MRI

Energy Technology Data Exchange (ETDEWEB)

El-Koussy, M; Loevblad, K O; Kiefer, C; Schroth, G [Department of Neuroradiology, University of Bern, Inselspital (Switzerland); Mathis, J; Stepper, F [Department of Neurology, University of Bern, Inselspital (Switzerland)

2002-03-01

Diffusion-weighted MRI demonstrated bright right temporoparietal cortex, right hippocampus, and left cerebellum in a 63-year-old female suffering a focal convulsive status epilepticus. Hyperperfusion was noted in the right temporoparietal region. Two days later, a tendency to normalization of most of the diffusion and perfusion changes was noted, apart from the right hippocampus which became brighter on diffusion- and T2-weighted images. On the tenth day the apparent diffusion coefficient was slightly elevated, getting brighter on T2-weighted images with suspected mild post-contrast enhancement. We postulate that the discharging right hippocampus suffered cytotoxic edema, which later progressed to cell damage. (orig.)

Protein kinase C involvement in focal adhesion formation

DEFF Research Database (Denmark)

Woods, A; Couchman, J R

1992-01-01

Matrix molecules such as fibronectin can promote cell attachment, spreading and focal adhesion formation. Although some interactions of fibronectin with cell surface receptors have now been identified, the consequent activation of intracellular messenger systems by cell/matrix interactions have...... still to be elucidated. We show here that the kinase inhibitors H7 and HA1004 reduce focal adhesion and stress fiber formation in response to fibronectin in a dose-dependent manner, and that activators of protein kinase C can promote their formation under conditions where they do not normally form....... Fibroblasts spread within 1h on substrata composed of fibronectin and formed focal adhesions by 3h, as monitored by interference reflection microscopy (IRM) and by labeling for talin, vinculin and integrin beta 1 subunits. In addition, stress fibers were visible. When cells were allowed to spread for 1h...

GUCY2C-directed CAR-T cells oppose colorectal cancer metastases without autoimmunity.

Science.gov (United States)

Magee, Michael S; Kraft, Crystal L; Abraham, Tara S; Baybutt, Trevor R; Marszalowicz, Glen P; Li, Peng; Waldman, Scott A; Snook, Adam E

2016-01-01

Adoptive T-cell therapy (ACT) is an emerging paradigm in which T cells are genetically modified to target cancer-associated antigens and eradicate tumors. However, challenges treating epithelial cancers with ACT reflect antigen targets that are not tumor-specific, permitting immune damage to normal tissues, and preclinical testing in artificial xenogeneic models, preventing prediction of toxicities in patients. In that context, mucosa-restricted antigens expressed by cancers exploit anatomical compartmentalization which shields mucosae from systemic antitumor immunity. This shielding may be amplified with ACT platforms employing antibody-based chimeric antigen receptors (CARs), which mediate MHC-independent recog-nition of antigens. GUCY2C is a cancer mucosa antigen expressed on the luminal surfaces of the intestinal mucosa in mice and humans, and universally overexpressed by colorectal tumors, suggesting its unique utility as an ACT target. T cells expressing CARs directed by a GUCY2C-specific antibody fragment recognized GUCY2C, quantified by expression of activation markers and cytokines. Further, GUCY2C CAR-T cells lysed GUCY2C-expressing, but not GUCY2C-deficient, mouse colorectal cancer cells. Moreover, GUCY2C CAR-T cells reduced tumor number and morbidity and improved survival in mice harboring GUCY2C-expressing colorectal cancer metastases. GUCY2C-directed T cell efficacy reflected CAR affinity and surface expression and was achieved without immune-mediated damage to normal tissues in syngeneic mice. These observations highlight the potential for therapeutic translation of GUCY2C-directed CAR-T cells to treat metastatic tumors, without collateral autoimmunity, in patients with metastatic colorectal cancer.

Engineering CAR-T cells.

Science.gov (United States)

Zhang, Cheng; Liu, Jun; Zhong, Jiang F; Zhang, Xi

2017-01-01

Chimeric antigen receptor redirected T cells (CAR-T cells) have achieved inspiring outcomes in patients with B cell malignancies, and are now being investigated in other hematologic malignancies and solid tumors. CAR-T cells are generated by the T cells from patients' or donors' blood. After the T cells are expanded and genetically modified, they are reinfused into the patients. However, many challenges still need to be resolved in order for this technology to gain widespread adoption. In this review, we first discuss the structure and evolution of chimeric antigen receptors. We then report on the tools used for production of CAR-T cells. Finally, we address the challenges posed by CAR-T cells.

Multidimensional Clusters of CD4+T Cell Dysfunction Are Primarily Associated with the CD4/CD8 Ratio in Chronic HIV Infection

DEFF Research Database (Denmark)

Frederiksen, Juliet Wairimu; Buggert, Marcus; Noyan, Kajsa

2015-01-01

was compared to a multidimensional clustering tool, FLOw Clustering with K (FLOCK) in two cohorts of 47 untreated HIV-infected individuals and 21 age and sex matched healthy controls. In order to reduce the subjectivity of FLOCK, we developed an "artificial reference", using 2% of all CD4+ gated T cells from...... each of the HIV-infected individuals. Principle component analyses demonstrated that using an artificial reference lead to a better separation of the HIV-infected individuals from the healthy controls as compared to using a single HIV-infected subject as a reference or analyzing data manually. Multiple...... correlation analyses between laboratory parameters and pathological CD4+ clusters revealed that the CD4/CD8 ratio was the preeminent surrogate marker of CD4+ T cells dysfunction using all three methods. Increased frequencies of an early-differentiated CD4+ T cell cluster with high CD38, HLA-DR and PD-1...

Induction of genomic instability and activation of autophagy in artificial human aneuploid cells

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Ariyoshi, Kentaro [Hirosaki University, Institute of Radiation Emergency Medicine, 66-1 Hon-cho, Hirosaki 036-8564 (Japan); Miura, Tomisato; Kasai, Kosuke; Fujishima, Yohei [Department of Biomedical Sciences, Hirosaki University Graduate School of Health Sciences, 66-1 Hon-cho, Hirosaki 036-8564 (Japan); Oshimura, Mitsuo [Chromosome Engineering Research Center (CERC), Tottori University, Nishicho 86, Yonago, Tottori 683-8503 (Japan); Yoshida, Mitsuaki A., E-mail: ariyoshi@hirosaki-u.ac.jp [Hirosaki University, Institute of Radiation Emergency Medicine, 66-1 Hon-cho, Hirosaki 036-8564 (Japan)

2016-08-15

Highlights: • Clones with artificial aneuploidy of chromosome 8 or chromosome 22 both show inhibited proliferation and genomic instability. • Increased autophagy was observed in the artificially aneuploid clones. • Inhibition of autophagy resulted in increased genomic instability and DNA damage. • Intracellular levels of reactive oxygen species were up-regulated in the artificially aneuploid clones. - Abstract: Chromosome missegregation can lead to a change in chromosome number known as aneuploidy. Although aneuploidy is a known hallmark of cancer cells, the various mechanisms by which altered gene and/or DNA copy number facilitate tumorigenesis remain unclear. To understand the effect of aneuploidy occurring in non-tumorigenic human breast epithelial cells, we generated clones harboring artificial aneuploidy using microcell-mediated chromosome transfer. Our results demonstrate that clones with artificial aneuploidy of chromosome 8 or chromosome 22 both show inhibited proliferation and genomic instability. Also, the increased autophagy was observed in the artificially aneuploidy clones, and inhibition of autophagy resulted in increased genomic instability and DNA damage. In addition, the intracellular levels of reactive oxygen species were up-regulated in the artificially aneuploid clones, and inhibition of autophagy further increased the production of reactive oxygen species. Together, these results suggest that even a single extraneous chromosome can induce genomic instability, and that autophagy triggered by aneuploidy-induced stress is a mechanism to protect cells bearing abnormal chromosome number.

Induction of genomic instability and activation of autophagy in artificial human aneuploid cells

International Nuclear Information System (INIS)

Ariyoshi, Kentaro; Miura, Tomisato; Kasai, Kosuke; Fujishima, Yohei; Oshimura, Mitsuo; Yoshida, Mitsuaki A.

2016-01-01

Highlights: • Clones with artificial aneuploidy of chromosome 8 or chromosome 22 both show inhibited proliferation and genomic instability. • Increased autophagy was observed in the artificially aneuploid clones. • Inhibition of autophagy resulted in increased genomic instability and DNA damage. • Intracellular levels of reactive oxygen species were up-regulated in the artificially aneuploid clones. - Abstract: Chromosome missegregation can lead to a change in chromosome number known as aneuploidy. Although aneuploidy is a known hallmark of cancer cells, the various mechanisms by which altered gene and/or DNA copy number facilitate tumorigenesis remain unclear. To understand the effect of aneuploidy occurring in non-tumorigenic human breast epithelial cells, we generated clones harboring artificial aneuploidy using microcell-mediated chromosome transfer. Our results demonstrate that clones with artificial aneuploidy of chromosome 8 or chromosome 22 both show inhibited proliferation and genomic instability. Also, the increased autophagy was observed in the artificially aneuploidy clones, and inhibition of autophagy resulted in increased genomic instability and DNA damage. In addition, the intracellular levels of reactive oxygen species were up-regulated in the artificially aneuploid clones, and inhibition of autophagy further increased the production of reactive oxygen species. Together, these results suggest that even a single extraneous chromosome can induce genomic instability, and that autophagy triggered by aneuploidy-induced stress is a mechanism to protect cells bearing abnormal chromosome number.

Polymerized-Type I Collagen Induces Upregulation of Foxp3-Expressing CD4 Regulatory T Cells and Downregulation of IL-17-Producing CD4+ T Cells (Th17 Cells in Collagen-Induced Arthritis

Directory of Open Access Journals (Sweden)

Janette Furuzawa-Carballeda

2012-01-01

Full Text Available Previous studies showed that polymerized-type I collagen (polymerized collagen exhibits potent immunoregulatory properties. This work evaluated the effect of intramuscular administration of polymerized collagen in early and established collagen-induced arthritis (CIA in mice and analyzed changes in Th subsets following therapy. Incidence of CIA was of 100% in mice challenged with type II collagen. Clinimorphometric analysis showed a downregulation of inflammation after administration of all treatments (P<0.05. Histological analysis showed that the CIA-mice group had extensive bone erosion, pannus and severe focal inflammatory infiltrates. In contrast, there was a remarkable reduction in the severity of arthritis in mice under polymerized collagen, methotrexate or methotrexate/polymerized collagen treatment. Polymerized Collagen but not methotrexate induced tissue joint regeneration. Polymerized Collagen and methotrexate/polymerized collagen but not methotrexate alone induces downregulation of CD4+/IL17A+ T cells and upregulation of Tregs and CD4+/IFN-γ+ T cells. Thus, Polymerized Collagen could be an effective therapeutic agent in early and established rheumatoid arthritis by exerting downregulation of autoimmune inflammation.

Cell clusters overlying focally disrupted mammary myoepithelial cell layers and adjacent cells within the same duct display different immunohistochemical and genetic features: implications for tumor progression and invasion

International Nuclear Information System (INIS)

Man, Yan-gao; Vinh, Tuyethoa N; Strauss, Brian L; Tai, Lisa; Barner, Ross; Vang, Russell; Saenger, Jeffrey S; Shekitka, Kris M; Bratthauer, Gary L; Wheeler, Darren T; Liang, Chang Y

2003-01-01

Our previous studies detected focal disruptions in myoepithelial cell layers of several ducts with carcinoma in situ. The cell cluster overlying each of the myoepithelial disruptions showed a marked reduction in or a total loss of immunoreactivity for the estrogen receptor (ER). This is in contrast to the adjacent cells within the same duct, which were strongly immunoreactive for the ER. The current study attempts to confirm and expand previous observations on a larger scale. Paraffin sections from 220 patients with ER-positive intraductal breast tumors were double immunostained with the same protocol previously used. Cross-sections of ducts lined by ≥ 40 epithelial cells were examined for myoepithelial cell layer disruptions and for ER expression. In five selected cases, ER-negative cells overlying the disrupted myoepithelial cell layer and adjacent ER-positive cells within the same duct were separately microdissected and assessed for loss of heterozygosity and microsatellite instability. Of the 220 cases with 5698 duct cross-sections examined, 94 showed disrupted myoepithelial cell layers with 405 focal disruptions. Of the 94 cases, 79 (84%) contained only ER-negative cell clusters, nine (9.6%) contained both ER-negative and ER-positive cell clusters, and six (6.4%) contained only ER-positive cell clusters overlying disrupted myoepithelial cell layers. Of the 405 disruptions, 350 (86.4%) were overlain by ER-negative cell clusters and 55 (13.6%) were overlain by ER-positive cell clusters (P < 0.01). Microdissected ER-negative and ER-positive cells within the same duct from all five selected cases displayed a different frequency or pattern of loss of heterozygosity and/or microsatellite instability at 10 of the 15 DNA markers. Cells overlying focally disrupted myoepithelial layers and their adjacent counterparts within the same duct displayed different immunohistochemical and molecular features. These features potentially represent an early sign of the formation

Chimeric Antigen Receptor T Cell (Car T Cell Therapy In Hematology

Directory of Open Access Journals (Sweden)

Pinar Ataca

2015-12-01

Full Text Available It is well demonstrated that immune system can control and eliminate cancer cells. Immune-mediated elimination of tumor cells has been discovered and is the basis of both cancer vaccines and cellular therapies including hematopoietic stem cell transplantation (HSCT. Adoptive T cell transfer has been improved to be more specific and potent and cause less off-target toxicities. Currently, there are two forms of engineered T cells being tested in clinical trials: T cell receptor (TCR and chimeric antigen receptor (CAR modified T cells. On July 1, 2014, the United States Food and Drug Administration granted ‘breakthrough therapy’ designation to anti-CD19 CAR T cell therapy. Many studies were conducted to evaluate the beneficiaries of this exciting and potent new treatment modality. This review summarizes the history of adoptive immunotherapy, adoptive immunotherapy using CARs, the CAR manufacturing process, preclinical-clinical studies, effectiveness and drawbacks of this strategy.

Nonmalignant T cells stimulate growth of T-cell lymphoma cells in the presence of bacterial toxins

DEFF Research Database (Denmark)

Woetmann, Anders; Lovato, Paola; Eriksen, Karsten W

2007-01-01

Bacterial toxins including staphylococcal enterotoxins (SEs) have been implicated in the pathogenesis of cutaneous T-cell lymphomas (CTCLs). Here, we investigate SE-mediated interactions between nonmalignant T cells and malignant T-cell lines established from skin and blood of CTCL patients....... The malignant CTCL cells express MHC class II molecules that are high-affinity receptors for SE. Although treatment with SE has no direct effect on the growth of the malignant CTCL cells, the SE-treated CTCL cells induce vigorous proliferation of the SE-responsive nonmalignant T cells. In turn, the nonmalignant...... T cells enhance proliferation of the malignant cells in an SE- and MHC class II-dependent manner. Furthermore, SE and, in addition, alloantigen presentation by malignant CTCL cells to irradiated nonmalignant CD4(+) T-cell lines also enhance proliferation of the malignant cells. The growth...

Sezary syndrome cells unlike normal circulating T lymphocytes fail to migrate following engagement of NT1 receptor.

Science.gov (United States)

Magazin, Marilyn; Poszepczynska-Guigné, Ewa; Bagot, Martine; Boumsell, Laurence; Pruvost, Christelle; Chalon, Pascale; Culouscou, Jean-Michel; Ferrara, Pascual; Bensussan, Armand

2004-01-01

Circulating malignant Sezary cells are a clonal proliferation of CD4+CD45RO+ T lymphocytes primarily involving the skin. To study the biology of these malignant T lymphocytes, we tested their ability to migrate in chemotaxis assays. Previously, we had shown that the neuropeptide neurotensin (NT) binds to freshly isolated Sezary malignant cells and induces through NT1 receptors the cell migration of the cutaneous T cell lymphoma cell line Cou-L. Here, we report that peripheral blood Sezary cells as well as the Sezary cell line Pno fail to migrate in response to neurotensin although they are capable of migrating to the chemokine stromal-cell-derived factor 1 alpha. This is in contrast with normal circulating CD4+ or CD8+ lymphocytes, which respond to both types of chemoattractants except after ex vivo short-time anti-CD3 monoclonal antibody activation, which abrogates the neurotensin-induced lymphocyte migration. Furthermore, we demonstrate that neurotensin-responsive T lymphocytes express the functional NT1 receptor responsible for chemotaxis. In these cells, but not in Sezary cells, neurotensin induces recruitment of phosphatidylinositol-3 kinase, and redistribution of phosphorylated cytoplasmic tyrosine kinase focal adhesion kinase and filamentous actin. Taken together, these results, which show functional distinctions between normal circulating lymphocytes and Sezary syndrome cells, contribute to further understanding of the physiopathology of these atypical cells.

Focal radiation therapy combined with 4-1BB activation and CTLA-4 blockade yields long-term survival and a protective antigen-specific memory response in a murine glioma model.

Directory of Open Access Journals (Sweden)

Zineb Belcaid

Full Text Available Glioblastoma (GBM is the most common malignant brain tumor in adults and is associated with a poor prognosis. Cytotoxic T lymphocyte antigen -4 (CTLA-4 blocking antibodies have demonstrated an ability to generate robust antitumor immune responses against a variety of solid tumors. 4-1BB (CD137 is expressed by activated T lymphocytes and served as a co-stimulatory signal, which promotes cytotoxic function. Here, we evaluate a combination immunotherapy regimen involving 4-1BB activation, CTLA-4 blockade, and focal radiation therapy in an immune-competent intracranial GBM model.GL261-luciferace cells were stereotactically implanted in the striatum of C57BL/6 mice. Mice were treated with a triple therapy regimen consisted of 4-1BB agonist antibodies, CTLA-4 blocking antibodies, and focal radiation therapy using a small animal radiation research platform and mice were followed for survival. Numbers of brain-infiltrating lymphocytes were analyzed by FACS analysis. CD4 or CD8 depleting antibodies were administered to determine the relative contribution of T helper and cytotoxic T cells in this regimen. To evaluate the ability of this immunotherapy to generate an antigen-specific memory response, long-term survivors were re-challenged with GL261 glioma en B16 melanoma flank tumors.Mice treated with triple therapy had increased survival compared to mice treated with focal radiation therapy and immunotherapy with 4-1BB activation and CTLA-4 blockade. Animals treated with triple therapy exhibited at least 50% long-term tumor free survival. Treatment with triple therapy resulted in a higher density of CD4+ and CD8+ tumor infiltrating lymphocytes. Mechanistically, depletion of CD4+ T cells abrogated the antitumor efficacy of triple therapy, while depletion of CD8+ T cells had no effect on the treatment response.Combination therapy with 4-1BB activation and CTLA-4 blockade in the setting of focal radiation therapy improves survival in an orthotopic mouse

Detection and Characterization of Focal Hepatic lesions using Magnetic resonance Imaging

International Nuclear Information System (INIS)

Pulgarin, Luis G; Delgado, Jorge Andres; Toro Nancy

2008-01-01

A retrospective one year study was performed from June 2006 to June 2007. A total of ten focal liver lesions in 60 patients were examined, describing their magnetic resonance (MR) characteristics, using T1, T2 and dynamic Gd-enhanced T1 weighted sequences with and without fat suppression. Lesions were classified into benign or malignant tumors and a diagnosis was proposed. Specific diagnoses such as simple cyst, abscess, hemangioma, focal nodular hyperplasia, hepatocellular carcinoma, and cholangiocarcinoma were reported.

Molecular biology of mycoplasmas: from the minimum cell concept to the artificial cell.

Science.gov (United States)

Cordova, Caio M M; Hoeltgebaum, Daniela L; Machado, Laís D P N; Santos, Larissa Dos

2016-01-01

Mycoplasmas are a large group of bacteria, sorted into different genera in the Mollicutes class, whose main characteristic in common, besides the small genome, is the absence of cell wall. They are considered cellular and molecular biology study models. We present an updated review of the molecular biology of these model microorganisms and the development of replicative vectors for the transformation of mycoplasmas. Synthetic biology studies inspired by these pioneering works became possible and won the attention of the mainstream media. For the first time, an artificial genome was synthesized (a minimal genome produced from consensus sequences obtained from mycoplasmas). For the first time, a functional artificial cell has been constructed by introducing a genome completely synthesized within a cell envelope of a mycoplasma obtained by transformation techniques. Therefore, this article offers an updated insight to the state of the art of these peculiar organisms' molecular biology.

Annexin A6 contributes to the invasiveness of breast carcinoma cells by influencing the organization and localization of functional focal adhesions

Energy Technology Data Exchange (ETDEWEB)

Sakwe, Amos M., E-mail: asakwe@mmc.edu [Department of Biochemistry and Cancer Biology, Meharry Medical College, Nashville, TN 37208 (United States); Koumangoye, Rainelli; Guillory, Bobby [Department of Biochemistry and Cancer Biology, Meharry Medical College, Nashville, TN 37208 (United States); Ochieng, Josiah [Department of Biochemistry and Cancer Biology, Meharry Medical College, Nashville, TN 37208 (United States); Center for Aids Health Disparity Research, Meharry Medical College, Nashville, TN 37208 (United States); Department of Cancer Biology, Vanderbilt University, Nashville, TN (United States)

2011-04-01

The interaction of annexin A6 (AnxA6) with membrane phospholipids and either specific extracellular matrix (ECM) components or F-actin suggests that it may influence cellular processes associated with rapid plasma membrane reorganization such as cell adhesion and motility. Here, we examined the putative roles of AnxA6 in adhesion-related cellular processes that contribute to breast cancer progression. We show that breast cancer cells secrete annexins via the exosomal pathway and that the secreted annexins are predominantly cell surface-associated. Depletion of AnxA6 in the invasive BT-549 breast cancer cells is accompanied by enhanced anchorage-independent cell growth but cell-cell cohesion, cell adhesion/spreading onto collagen type IV or fetuin-A, cell motility and invasiveness were strongly inhibited. To explain the loss in adhesion/motility, we show that vinculin-based focal adhesions in the AnxA6-depleted BT-549 cells are elongated and randomly distributed. These focal contacts are also functionally defective because the activation of focal adhesion kinase and the phosphoinositide-3 kinase/Akt pathway were strongly inhibited while the MAP kinase pathway remained constitutively active. Compared with normal human breast tissues, reduced AnxA6 expression in breast carcinoma tissues correlates with enhanced cell proliferation. Together this suggests that reduced AnxA6 expression contributes to breast cancer progression by promoting the loss of functional cell-cell and/or cell-ECM contacts and anchorage-independent cell proliferation.

Annexin A6 contributes to the invasiveness of breast carcinoma cells by influencing the organization and localization of functional focal adhesions

International Nuclear Information System (INIS)

Sakwe, Amos M.; Koumangoye, Rainelli; Guillory, Bobby; Ochieng, Josiah

2011-01-01

The interaction of annexin A6 (AnxA6) with membrane phospholipids and either specific extracellular matrix (ECM) components or F-actin suggests that it may influence cellular processes associated with rapid plasma membrane reorganization such as cell adhesion and motility. Here, we examined the putative roles of AnxA6 in adhesion-related cellular processes that contribute to breast cancer progression. We show that breast cancer cells secrete annexins via the exosomal pathway and that the secreted annexins are predominantly cell surface-associated. Depletion of AnxA6 in the invasive BT-549 breast cancer cells is accompanied by enhanced anchorage-independent cell growth but cell-cell cohesion, cell adhesion/spreading onto collagen type IV or fetuin-A, cell motility and invasiveness were strongly inhibited. To explain the loss in adhesion/motility, we show that vinculin-based focal adhesions in the AnxA6-depleted BT-549 cells are elongated and randomly distributed. These focal contacts are also functionally defective because the activation of focal adhesion kinase and the phosphoinositide-3 kinase/Akt pathway were strongly inhibited while the MAP kinase pathway remained constitutively active. Compared with normal human breast tissues, reduced AnxA6 expression in breast carcinoma tissues correlates with enhanced cell proliferation. Together this suggests that reduced AnxA6 expression contributes to breast cancer progression by promoting the loss of functional cell-cell and/or cell-ECM contacts and anchorage-independent cell proliferation.

Neuron-mediated generation of regulatory T cells from encephalitogenic T cells suppresses EAE

DEFF Research Database (Denmark)

Liu, Yawei; Teige, Ingrid; Birnir, Bryndis

2006-01-01

Neurons have been neglected as cells with a major immune-regulatory function because they do not express major histocompatibility complex class II. Our data show that neurons are highly immune regulatory, having a crucial role in governing T-cell response and central nervous system (CNS) inflamma......Neurons have been neglected as cells with a major immune-regulatory function because they do not express major histocompatibility complex class II. Our data show that neurons are highly immune regulatory, having a crucial role in governing T-cell response and central nervous system (CNS......) inflammation. Neurons induce the proliferation of activated CD4+ T cells through B7-CD28 and transforming growth factor (TGF)-beta1-TGF-beta receptor signaling pathways, resulting in amplification of T-cell receptor signaling through phosphorylated ZAP-70, interleukin (IL)-2 and IL-9. The interaction between...... neurons and T cells results in the conversion of encephalitogenic T cells to CD25+ TGF-beta1+ CTLA-4+ FoxP3+ T regulatory (Treg) cells that suppress encephalitogenic T cells and inhibit experimental autoimmune encephalomyelitis. Suppression is dependent on cytotoxic T lymphocyte antigen (CTLA)-4...

Inhibition of cell migration by focal adhesion kinase: Time-dependent difference in integrin-induced signaling between endothelial and hepatoblastoma cells.

Science.gov (United States)

Yu, Hongchi; Gao, Min; Ma, Yunlong; Wang, Lijuan; Shen, Yang; Liu, Xiaoheng

2018-05-01

angiogenesis plays an important role in the development and progression of tumors, and it involves a series of signaling pathways contributing to the migration of endothelial cells for vascularization and to the invasion of cancer cells for secondary tumor formation. Among these pathways, the focal adhesion kinase (FAK) signaling cascade has been implicated in a variety of human cancers in connection with cell adhesion and migration events leading to tumor angiogenesis, metastasis and invasion. Therefore, the inhibition of FAK in endothelial and/or cancer cells is a potential target for anti‑angiogenic therapy. In the present study, a small‑molecule FAK inhibitor, 1,2,4,5-benzenetetramine tetrahydrochloride (Y15), was used to study the effects of FAK inhibition on the adhesion and migration behaviors of vascular endothelial cells (VECs) and human hepatoblastoma cells. Furthermore, the time-dependent differences in proteins associated with the integrin-mediated FAK/Rho GTPases signaling pathway within 2 h were examined. The results indicated that the inhibition of FAK significantly decreased the migration ability of VECs and human hepatoblastoma cells in a dose-dependent manner. Inhibition of FAK promoted cell detachment by decreasing the expression of focal adhesion components, and blocked cell motility by reducing the level of Rho GTPases. However, the expression of crucial proteins involved in integrin-induced signaling in two cell lines exhibited a time-dependent difference with increased duration of FAK inhibitor treatment, suggesting different mechanisms of FAK-mediated cell migration behavior. These results suggest that the mechanism underlying FAK-mediated adhesion and migration behavior differs among various cells, which is expected to provide evidence for future FAK therapy targeted against tumor angiogenesis.

CD4+ T cell effects on CD8+ T cell location defined using bioluminescence.

Directory of Open Access Journals (Sweden)

Mitra Azadniv

2011-01-01

Full Text Available T lymphocytes of the CD8+ class are critical in delivering cytotoxic function and in controlling viral and intracellular infections. These cells are "helped" by T lymphocytes of the CD4+ class, which facilitate their activation, clonal expansion, full differentiation and the persistence of memory. In this study we investigated the impact of CD4+ T cells on the location of CD8+ T cells, using antibody-mediated CD4+ T cell depletion and imaging the antigen-driven redistribution of bioluminescent CD8+ T cells in living mice. We documented that CD4+ T cells influence the biodistribution of CD8+ T cells, favoring their localization to abdominal lymph nodes. Flow cytometric analysis revealed that this was associated with an increase in the expression of specific integrins. The presence of CD4+ T cells at the time of initial CD8+ T cell activation also influences their biodistribution in the memory phase. Based on these results, we propose the model that one of the functions of CD4+ T cell "help" is to program the homing potential of CD8+ T cells.

γδ T Cells Support Pancreatic Oncogenesis by Restraining αβ T Cell Activation.

Science.gov (United States)

Daley, Donnele; Zambirinis, Constantinos Pantelis; Seifert, Lena; Akkad, Neha; Mohan, Navyatha; Werba, Gregor; Barilla, Rocky; Torres-Hernandez, Alejandro; Hundeyin, Mautin; Mani, Vishnu Raj Kumar; Avanzi, Antonina; Tippens, Daniel; Narayanan, Rajkishen; Jang, Jung-Eun; Newman, Elliot; Pillarisetty, Venu Gopal; Dustin, Michael Loran; Bar-Sagi, Dafna; Hajdu, Cristina; Miller, George

2016-09-08

Inflammation is paramount in pancreatic oncogenesis. We identified a uniquely activated γδT cell population, which constituted ∼40% of tumor-infiltrating T cells in human pancreatic ductal adenocarcinoma (PDA). Recruitment and activation of γδT cells was contingent on diverse chemokine signals. Deletion, depletion, or blockade of γδT cell recruitment was protective against PDA and resulted in increased infiltration, activation, and Th1 polarization of αβT cells. Although αβT cells were dispensable to outcome in PDA, they became indispensable mediators of tumor protection upon γδT cell ablation. PDA-infiltrating γδT cells expressed high levels of exhaustion ligands and thereby negated adaptive anti-tumor immunity. Blockade of PD-L1 in γδT cells enhanced CD4(+) and CD8(+) T cell infiltration and immunogenicity and induced tumor protection suggesting that γδT cells are critical sources of immune-suppressive checkpoint ligands in PDA. We describe γδT cells as central regulators of effector T cell activation in cancer via novel cross-talk. Copyright © 2016 Elsevier Inc. All rights reserved.

Focal splenic masses of the extramedullary hematopoiesis

International Nuclear Information System (INIS)

Incedayi, M.; Sivrioglu, A.

2012-01-01

Full text: Extramedullary hematopoiesis arises from pleuripotential stem cells distributed throughout the body. It is most common in patients with congenital hemolytic anemia, such as thalassemia, sickle cell anemia and hereditary spherocytosis as a response to ineffective red blood cell formation. Although microscopic foci of Extramedullary hematopoiesis are commonly seen in the spleen and liver parenchyma, focal mass-like lesion of extramedullary hematopoiesis in the liver and spleen are rare. We report a case of intrasplenic focal extramedullary hematopoiesis lesions and the imaging features of extramedullary hematopoiesis on computed tomography and magnetic resonance imaging. Extramedullary hematopoiesis should always be considered as a diagnosis in a patient with a known hematological disorder

Supernatural T cells: genetic modification of T cells for cancer therapy.

Science.gov (United States)

Kershaw, Michael H; Teng, Michele W L; Smyth, Mark J; Darcy, Phillip K

2005-12-01

Immunotherapy is receiving much attention as a means of treating cancer, but complete, durable responses remain rare for most malignancies. The natural immune system seems to have limitations and deficiencies that might affect its ability to control malignant disease. An alternative to relying on endogenous components in the immune repertoire is to generate lymphocytes with abilities that are greater than those of natural T cells, through genetic modification to produce 'supernatural' T cells. This Review describes how such T cells can circumvent many of the barriers that are inherent in the tumour microenvironment while optimizing T-cell specificity, activation, homing and antitumour function.

Conformational Dynamics of the Focal Adhesion Targeting Domain Control Specific Functions of Focal Adhesion Kinase in Cells

KAUST Repository

Kadaré, Gress

2015-01-02

Focal adhesion (FA) kinase (FAK) regulates cell survival and motility by transducing signals from membrane receptors. The C-terminal FA targeting (FAT) domain of FAK fulfils multiple functions, including recruitment to FAs through paxillin binding. Phosphorylation of FAT on Tyr925 facilitates FA disassembly and connects to the MAPK pathway through Grb2 association, but requires dissociation of the first helix (H1) of the four-helix bundle of FAT. We investigated the importance of H1 opening in cells by comparing the properties of FAK molecules containing wild-type or mutated FAT with impaired or facilitated H1 openings. These mutations did not alter the activation of FAK, but selectively affected its cellular functions, including self-association, Tyr925 phosphorylation, paxillin binding, and FA targeting and turnover. Phosphorylation of Tyr861, located between the kinase and FAT domains, was also enhanced by the mutation that opened the FAT bundle. Similarly phosphorylation of Ser910 by ERK in response to bombesin was increased by FAT opening. Although FAK molecules with the mutation favoring FAT opening were poorly recruited at FAs, they efficiently restored FA turnover and cell shape in FAK-deficient cells. In contrast, the mutation preventing H1 opening markedly impaired FAK function. Our data support the biological importance of conformational dynamics of the FAT domain and its functional interactions with other parts of the molecule.

Rapid expansion of T cells: Effects of culture and cryopreservation and importance of short-term cell recovery.

Science.gov (United States)

Sadeghi, Arian; Ullenhag, Gustav; Wagenius, Gunnar; Tötterman, Thomas H; Eriksson, Fredrik

2013-06-01

Successful cell therapy relies on the identification and mass expansion of functional cells for infusion. Cryopreservation of cells is an inevitable step in most cell therapies which also entails consequences for the frozen cells. This study assessed the impact of cryopreservation and the widely used protocol for rapid expansion of T lymphocytes. The effects on cell viability, immunocompetence and the impact on apoptotic and immunosuppressive marker expression were analyzed using validated assays. Cryopreservation of lymphocytes during the rapid expansion protocol did not affect cell viability. Lymphocytes that underwent mass expansion or culture in high dose IL-2 were unable to respond to PHA stimulation by intracellular ATP production immediately after thawing (ATP = 16 ± 11 ng/ml). However, their reactivity to PHA was regained within 48 hours of recovery (ATP = 356 ± 61 ng/ml). Analysis of mRNA levels revealed downregulation of TGF-β and IL-10 at all time points. Culture in high dose IL-2 led to upregulation of p73 and BCL-2 mRNA levels while FoxP3 expression was elevated after culture in IL-2 and artificial TCR stimuli. FoxP3 levels decreased after short-term recovery without IL-2 or stimulation. Antigen specificity, as determined by IFNγ secretion, was unaffected by cryopreservation but was completely lost after addition of high dose IL-2 and artificial TCR stimuli. In conclusion, allowing short-time recovery of mass expanded and cryopreserved cells before reinfusion could enhance the outcome of adoptive cell therapy as the cells regain immune competence and specificity.

A novel method to generate T-cell receptor-deficient chimeric antigen receptor T cells.

Science.gov (United States)

Kamiya, Takahiro; Wong, Desmond; Png, Yi Tian; Campana, Dario

2018-03-13

Practical methods are needed to increase the applicability and efficacy of chimeric antigen receptor (CAR) T-cell therapies. Using donor-derived CAR-T cells is attractive, but expression of endogenous T-cell receptors (TCRs) carries the risk for graft-versus-host-disease (GVHD). To remove surface TCRαβ, we combined an antibody-derived single-chain variable fragment specific for CD3ε with 21 different amino acid sequences predicted to retain it intracellularly. After transduction in T cells, several of these protein expression blockers (PEBLs) colocalized intracellularly with CD3ε, blocking surface CD3 and TCRαβ expression. In 25 experiments, median TCRαβ expression in T lymphocytes was reduced from 95.7% to 25.0%; CD3/TCRαβ cell depletion yielded virtually pure TCRαβ-negative T cells. Anti-CD3ε PEBLs abrogated TCRαβ-mediated signaling, without affecting immunophenotype or proliferation. In anti-CD3ε PEBL-T cells, expression of an anti-CD19-41BB-CD3ζ CAR induced cytokine secretion, long-term proliferation, and CD19 + leukemia cell killing, at rates meeting or exceeding those of CAR-T cells with normal CD3/TCRαβ expression. In immunodeficient mice, anti-CD3ε PEBL-T cells had markedly reduced GVHD potential; when transduced with anti-CD19 CAR, these T cells killed engrafted leukemic cells. PEBL blockade of surface CD3/TCRαβ expression is an effective tool to prepare allogeneic CAR-T cells. Combined PEBL and CAR expression can be achieved in a single-step procedure, is easily adaptable to current cell manufacturing protocols, and can be used to target other T-cell molecules to further enhance CAR-T-cell therapies. © 2018 by The American Society of Hematology.

T-cells fighting B-cell lymphoproliferative malignancies: the emerging field of CD19 CAR T-cell therapy

NARCIS (Netherlands)

Heijink, D. M.; Kater, A. P.; Hazenberg, M. D.; Hagenbeek, A.; Kersten, M. J.

2016-01-01

CAR T-cells are autologous T-cells transduced with a chimeric antigen receptor (CAR). The CAR contains an antigen recognition part (originating from an antibody), a T-cell receptor transmembrane and cytoplasmic signalling part, and one or more co-stimulatory domains. While CAR T-cells can be

Recurrent Bilateral Focal Myositis.

Science.gov (United States)

Nagafuchi, Hiroko; Nakano, Hiromasa; Ooka, Seido; Takakuwa, Yukiko; Yamada, Hidehiro; Tadokoro, Mamoru; Shimojo, Sadatomo; Ozaki, Shoichi

This report describes a rare case of recurrent bilateral focal myositis and its successful treatment via methotrexate. A 38-year-old man presented myalgia of the right gastrocnemius in May 2005. Magnetic resonance imaging showed very high signal intensity in the right gastrocnemius on short-tau inversion recovery images. A muscle biopsy revealed inflammatory CD4+ cell-dominant myogenic change. Focal myositis was diagnosed. The first steroid treatment was effective. Tapering of prednisolone, however, repeatedly induced myositis relapse, which progressed to multiple muscle lesions of both lower limbs. Initiation of methotrexate finally allowed successful tapering of prednisolone, with no relapse in the past 4 years.

T cell immunity

OpenAIRE

Emel Bülbül Başkan

2013-01-01

Since birth, our immune system is constantly bombarded with self-antigens and foreign pathogens. To stay healthy, complex immune strategies have evolved in our immune system to maintain self-tolerance and to defend against foreign pathogens. Effector T cells are the key players in steering the immune responses to execute immune functions. While effector T cells were initially identified to be immune promoting, recent studies unraveled negative regulatory functions of effector T cells...

Anti-regulatory T cells

DEFF Research Database (Denmark)

Andersen, Mads Hald

2017-01-01

responses to tumours or inhibiting autoimmunity development. However, recent studies report the discovery of self-reactive pro-inflammatory T cells—termed anti-regulatory T cells (anti-Tregs)—that target immune-suppressive cells. Thus, regulatory cells can now be defined as both cells that suppress immune...... reactions as well as effector cells that counteract the effects of suppressor cells and support immune reactions. Self-reactive anti-Tregs have been described that specifically recognize human leukocyte antigen-restricted epitopes derived from proteins that are normally expressed by regulatory immune cells......Our initial understanding of immune-regulatory cells was based on the discovery of suppressor cells that assure peripheral T-cell tolerance and promote immune homeostasis. Research has particularly focused on the importance of regulatory T cells (Tregs) for immune modulation, e.g. directing host...

Self-reactive T cells

DEFF Research Database (Denmark)

Becker, Jürgen C; thor Straten, Per; Andersen, Mads Hald

2014-01-01

-proteins expressed in regulatory immune cells have been reported, especially in patients with cancer. The seemingly lack of tolerance toward such proteins is interesting, as it suggests a regulatory function of self-reactive T (srT) cells, which may be important for the fine tuning of the immune system......The immune system is a tightly regulated and complex system. An important part of this immune regulation is the assurance of tolerance toward self-antigens to maintain immune homeostasis. However, in recent years, antigen-specific cellular immune responses toward several normal self....... In particular, surprising has been the description of cytotoxic srT cells that are able to eliminate normal regulatory immune cells. Such srT cells may be important as effector cells that suppress regulatory suppressor cells. The current knowledge of the nature and function of srT cells is still limited. Still...

Gap junctions at the dendritic cell-T cell interface are key elements for antigen-dependent T cell activation.

Science.gov (United States)

Elgueta, Raul; Tobar, Jaime A; Shoji, Kenji F; De Calisto, Jaime; Kalergis, Alexis M; Bono, Maria R; Rosemblatt, Mario; Sáez, Juan C

2009-07-01

The acquired immune response begins with Ag presentation by dendritic cells (DCs) to naive T cells in a heterocellular cell-cell contact-dependent process. Although both DCs and T cells are known to express connexin43, a gap junction protein subunit, the role of connexin43 on the initiation of T cell responses remains to be elucidated. In the present work, we report the formation of gap junctions between DCs and T cells and their role on T cell activation during Ag presentation by DCs. In cocultures of DCs and T cells, Lucifer yellow microinjected into DCs is transferred to adjacent transgenic CD4(+) T cells, only if the specific antigenic peptide was present at least during the first 24 h of cocultures. This dye transfer was sensitive to gap junction blockers, such as oleamide, and small peptides containing the extracellular loop sequences of conexin. Furthermore, in this system, gap junction blockers drastically reduced T cell activation as reflected by lower proliferation, CD69 expression, and IL-2 secretion. This lower T cell activation produced by gap junction blockers was not due to a lower expression of CD80, CD86, CD40, and MHC-II on DCs. Furthermore, gap junction blocker did not affect polyclonal activation of T cell induced with anti-CD3 plus anti-CD28 Abs in the absence of DCs. These results strongly suggest that functional gap junctions assemble at the interface between DCs and T cells during Ag presentation and that they play an essential role in T cell activation.

Recent Theoretical Approaches to Minimal Artificial Cells

Directory of Open Access Journals (Sweden)

Fabio Mavelli

2014-05-01

Full Text Available Minimal artificial cells (MACs are self-assembled chemical systems able to mimic the behavior of living cells at a minimal level, i.e. to exhibit self-maintenance, self-reproduction and the capability of evolution. The bottom-up approach to the construction of MACs is mainly based on the encapsulation of chemical reacting systems inside lipid vesicles, i.e. chemical systems enclosed (compartmentalized by a double-layered lipid membrane. Several researchers are currently interested in synthesizing such simple cellular models for biotechnological purposes or for investigating origin of life scenarios. Within this context, the properties of lipid vesicles (e.g., their stability, permeability, growth dynamics, potential to host reactions or undergo division processes… play a central role, in combination with the dynamics of the encapsulated chemical or biochemical networks. Thus, from a theoretical standpoint, it is very important to develop kinetic equations in order to explore first—and specify later—the conditions that allow the robust implementation of these complex chemically reacting systems, as well as their controlled reproduction. Due to being compartmentalized in small volumes, the population of reacting molecules can be very low in terms of the number of molecules and therefore their behavior becomes highly affected by stochastic effects both in the time course of reactions and in occupancy distribution among the vesicle population. In this short review we report our mathematical approaches to model artificial cell systems in this complex scenario by giving a summary of three recent simulations studies on the topic of primitive cell (protocell systems.

γ/δ T cell subsets in human aging using the classical α/β T cell model.

Science.gov (United States)

Vasudev, Anusha; Ying, Crystal Tan Tze; Ayyadhury, Shamini; Puan, Kia Joo; Andiappan, Anand Kumar; Nyunt, Ma Shwe Zin; Shadan, Nurhidaya Binte; Mustafa, Seri; Low, Ivy; Rotzschke, Olaf; Fulop, Tamas; Ng, Tze Pin; Larbi, Anis

2014-10-01

Aging is associated with an increased susceptibility to infections and diseases. It has also been associated with reduced functionality and altered distribution of immune cells, especially T cells. Whereas classical α/β T cells, especially CD8(+) T cells, were shown to be highly susceptible to aging, the effects of viral persistent stimulations on the fate of γ/δ T cells are much less documented. Healthy, elderly individuals of Chinese ethnical background were recruited under the aegis of SLAS-II. In this observational study, γ/δ T cell populations were characterized by flow cytometry and compared with the α/β CD4(+) and CD8(+) T cells in elderly and young controls. In our study, we identified a reduced frequency of γ/δ T cells but not α/β T cells with aging. The classical markers of α/β T cell aging, including CD28, CD27, and CD57, did not prove significant for γ/δ T cells. The extreme range of expression of these markers in γ/δ T cells was responsible for the lack of relationship between γ/δ T cell subsets, CD4/CD8 ratio, and anti-CMV titers that was significant for α/β T cells and, especially, CD8(+) T cells. Although markers of aging for γ/δ T cells are not clearly identified, our data collectively suggest that the presence of CD27 γ/δ T cells is associated with markers of α/β T cell aging. © 2014 Society for Leukocyte Biology.

MRI of experimental focal cerebral ischemia in sheep

International Nuclear Information System (INIS)

Foerschler, A.; Waldmin, D.; Gille, U.; Leipzig Univ.; Zimmer, C.

2007-01-01

Purpose: With respect to the specific characteristic of rete mirabile epidurale rostrale in sheep, the aim of this study was to investigate the use of time of flight (TOF) magnetic resonance angiography (MRA) to observe vascular anatomy and to validate MCA occlusion in a new model of experimental focal cerebral ischemia by permanent middle cerebral artery (MCA) occlusion in sheep (designed to study stroke therapy using autologous stem cells from umbilical cord blood). Furthermore, we wanted to assess the extent and natural time course of ischemic focal brain injury in sheep using functional and morphological magnetic resonance imaging (MRI). Materials and Method: 13 Merino sheep were examined. In 4 of the animals all, in 5 sheep 1 or 2 MCA branches were occluded and in 1 one case touched (sham operation). 4 controls did not undergo a surgical procedure. 23 MRI sessions were performed in 10 sheep. These sessions included T1, T2, T2 * sequences, diffusion-weighted imaging (DWI) and TOF MRA before and 2 - 46 days after the onset of stroke using a 1.5T clinical MR scanner. Corrosion casts of the cerebral arteries of 3 sheep were prepared and compared to MRA. Results: The MRA visualized the vessel anatomy or occlusion distal to the rete mirabile. Anatomical variants concerning the variant origin of the MCA and inconstant arteria choroidea rostralis and communicans rostralis were revealed. Sheep with occluded left MCA showed space occupying lesions with a drop in ADC values. Depending on the number of preserved MCA branches (0; 1; 2), highly significant (p < 0.001) differences in lesion size (21 ± 5.7; 13; 1.7 ± 1.3 ml) could be found. No indication of ischemia but minimal contusion damage was observed in the sham operated animal. (orig.)

Construction of membrane-bound artificial cells using microfluidics: a new frontier in bottom-up synthetic biology.

Science.gov (United States)

Elani, Yuval

2016-06-15

The quest to construct artificial cells from the bottom-up using simple building blocks has received much attention over recent decades and is one of the grand challenges in synthetic biology. Cell mimics that are encapsulated by lipid membranes are a particularly powerful class of artificial cells due to their biocompatibility and the ability to reconstitute biological machinery within them. One of the key obstacles in the field centres on the following: how can membrane-based artificial cells be generated in a controlled way and in high-throughput? In particular, how can they be constructed to have precisely defined parameters including size, biomolecular composition and spatial organization? Microfluidic generation strategies have proved instrumental in addressing these questions. This article will outline some of the major principles underpinning membrane-based artificial cells and their construction using microfluidics, and will detail some recent landmarks that have been achieved. © 2016 The Author(s).

ArtinM Mediates Murine T Cell Activation and Induces Cell Death in Jurkat Human Leukemic T Cells

Science.gov (United States)

Oliveira-Brito, Patrícia Kellen Martins; Gonçalves, Thiago Eleutério; Vendruscolo, Patrícia Edivânia; Roque-Barreira, Maria Cristina

2017-01-01

The recognition of cell surface glycans by lectins may be critical for the innate and adaptive immune responses. ArtinM, a d-mannose-binding lectin from Artocarpus heterophyllus, activates antigen-presenting cells by recognizing TLR2 N-glycans and induces Th1 immunity. We recently demonstrated that ArtinM stimulated CD4+ T cells to produce proinflammatory cytokines. Here, we further studied the effects of ArtinM on adaptive immune cells. We showed that ArtinM activates murine CD4+ and CD8+ T cells, augmenting their positivity for CD25, CD69, and CD95 and showed higher interleukin (IL)-2 and interferon (IFN)-γ production. The CD4+ T cells exhibited increased T-bet expression in response to ArtinM, and IL-2 production by CD4+ and CD8+ T cells depended on the recognition of CD3εγ-chain glycans by ArtinM. The ArtinM effect on aberrantly-glycosylated neoplastic lymphocytes was studied in Jurkat T cells, in which ArtinM induced IL-2, IFN-γ, and IL-1β production, but decreased cell viability and growth. A higher frequency of AnnexinV- and propidium iodide-stained cells demonstrated the induction of Jurkat T cells apoptosis by ArtinM, and this apoptotic response was reduced by caspases and protein tyrosine kinase inhibitors. The ArtinM effects on murine T cells corroborated with the immunomodulatory property of lectin, whereas the promotion of Jurkat T cells apoptosis may reflect a potential applicability of ArtinM in novel strategies for treating lymphocytic leukemia. PMID:28665310

Management of Localized Prostate Cancer by Focal Transurethral Resection of Prostate Cancer: An Application of Radical TUR-PCa to Focal Therapy.

Science.gov (United States)

Morita, Masaru; Matsuura, Takeshi

2012-01-01

Background. We analyzed radical TUR-PCa against localized prostate cancer. Patients and Methods. Seventy-nine out of 209 patients with prostate cancer in one lobe were studied. Patients' age ranged from 58 to 91 years and preoperative PSA, 0.70 to 17.30 ng/mL. In other 16 additional patients we performed focal TUR-PCa. Patients' age ranged from 51 to 87 years and preoperative PSA, 1.51 to 25.74 ng/mL. Results. PSA failure in radical TUR-PCa was 5.1% during the mean follow-up period of 58.9 months. The actuarial biochemical non-recurrence rate was 98.2% for pT2a and 90.5% for pT2b. Bladder neck contracture occurred in 28 patients (35.4%). In 209 patients, pathological study revealed prostate cancer of the peripheral zone near the neurovascular bundle bilaterally in 25%, unilaterally in 39% and no cancer bilaterally in 35%, suggesting the possibility of focal TUR-PCa. Postoperative PSA of 16 patients treated by focal TUR-PCa was stable between 0.007 and 0.406 ng/mL at 24.2 months' follow-up. No patients suffered from urinary incontinence. Bladder neck contracture developed in only 1 patient and all 5 patients underwent nerve-preserving TUR-PCa did not show erectile dysfunction. Conclusion. Focal TUR-PCa was considered to be a promising option among focal therapies against localized prostate cancer.

Management of Localized Prostate Cancer by Focal Transurethral Resection of Prostate Cancer: An Application of Radical TUR-PCa to Focal Therapy

Directory of Open Access Journals (Sweden)

Masaru Morita

2012-01-01

Full Text Available Background. We analyzed radical TUR-PCa against localized prostate cancer. Patients and Methods. Seventy-nine out of 209 patients with prostate cancer in one lobe were studied. Patients’ age ranged from 58 to 91 years and preoperative PSA, 0.70 to 17.30 ng/mL. In other 16 additional patients we performed focal TUR-PCa. Patients’ age ranged from 51 to 87 years and preoperative PSA, 1.51 to 25.74 ng/mL. Results. PSA failure in radical TUR-PCa was 5.1% during the mean follow-up period of 58.9 months. The actuarial biochemical non-recurrence rate was 98.2% for pT2a and 90.5% for pT2b. Bladder neck contracture occurred in 28 patients (35.4%. In 209 patients, pathological study revealed prostate cancer of the peripheral zone near the neurovascular bundle bilaterally in 25%, unilaterally in 39% and no cancer bilaterally in 35%, suggesting the possibility of focal TUR-PCa. Postoperative PSA of 16 patients treated by focal TUR-PCa was stable between 0.007 and 0.406 ng/mL at 24.2 months’ follow-up. No patients suffered from urinary incontinence. Bladder neck contracture developed in only 1 patient and all 5 patients underwent nerve-preserving TUR-PCa did not show erectile dysfunction. Conclusion. Focal TUR-PCa was considered to be a promising option among focal therapies against localized prostate cancer.

An artificial light-harvesting array constructed from multiple Bodipy dyes.

Science.gov (United States)

Ziessel, Raymond; Ulrich, Gilles; Haefele, Alexandre; Harriman, Anthony

2013-07-31

An artificial light-harvesting array, comprising 21 discrete chromophores arranged in a rational manner, has been synthesized and characterized fully. The design strategy follows a convergent approach that leads to a molecular-scale funnel, having an effective chromophore concentration of 0.6 M condensed into ca. 55 nm(3), able to direct the excitation energy to a focal point. A cascade of electronic energy-transfer steps occurs from the rim to the focal point, with the rate slowing down as the exciton moves toward its ultimate target. Situated midway along each branch of the V-shaped array, two chromophoric relays differ only slightly in terms of their excitation energies, and this situation facilitates reverse energy transfer. Thus, the excitation energy becomes spread around the array, a situation reminiscent of a giant holding pattern for the photon that can sample many different chromophores before being trapped by the terminal acceptor. At high photon flux under conditions of relatively slow off-load to a device, such as a solar cell, electronic energy transfer encounters one or more barriers that hinder forward progress of the exciton and thereby delays arrival of the second photon. Preliminary studies have addressed the ability of the array to function as a sensitizer for amorphous silicon solar cells.

The cell biology of T-dependent B cell activation

DEFF Research Database (Denmark)

Owens, T; Zeine, R

1989-01-01

The requirement that CD4+ helper T cells recognize antigen in association with class II Major Histocompatibility Complex (MHC) encoded molecules constrains T cells to activation through intercellular interaction. The cell biology of the interactions between CD4+ T cells and antigen-presenting cells...... includes multipoint intermolecular interactions that probably involve aggregation of both polymorphic and monomorphic T cell surface molecules. Such aggregations have been shown in vitro to markedly enhance and, in some cases, induce T cell activation. The production of T-derived lymphokines that have been...... implicated in B cell activation is dependent on the T cell receptor for antigen and its associated CD3 signalling complex. T-dependent help for B cell activation is therefore similarly MHC-restricted and involves T-B intercellular interaction. Recent reports that describe antigen-independent B cell...

Recruitment of focal adhesion kinase and paxillin to β1 integrin promotes cancer cell migration via mitogen activated protein kinase activation

International Nuclear Information System (INIS)

Crowe, David L; Ohannessian, Arthur

2004-01-01

Integrin-extracellular matrix interactions activate signaling cascades such as mitogen activated protein kinases (MAPK). Integrin binding to extracellular matrix increases tyrosine phosphorylation of focal adhesion kinase (FAK). Inhibition of FAK activity by expression of its carboxyl terminus decreases cell motility, and cells from FAK deficient mice also show reduced migration. Paxillin is a focal adhesion protein which is also phosphorylated on tyrosine. FAK recruitment of paxillin to the cell membrane correlates with Shc phosphorylation and activation of MAPK. Decreased FAK expression inhibits papilloma formation in a mouse skin carcinogenesis model. We previously demonstrated that MAPK activation was required for growth factor induced in vitro migration and invasion by human squamous cell carcinoma (SCC) lines. Adapter protein recruitment to integrin subunits was examined by co-immunoprecipitation in SCC cells attached to type IV collagen or plastic. Stable clones overexpressing FAK or paxillin were created using the lipofection technique. Modified Boyden chambers were used for invasion assays. In the present study, we showed that FAK and paxillin but not Shc are recruited to the β1 integrin cytoplasmic domain following attachment of SCC cells to type IV collagen. Overexpression of either FAK or paxillin stimulated cancer cell migration on type IV collagen and invasion through reconstituted basement membrane which was dependent on MAPK activity. We concluded that recruitment of focal adhesion kinase and paxillin to β1 integrin promoted cancer cell migration via the mitogen activated protein kinase pathway

Recruitment of focal adhesion kinase and paxillin to β1 integrin promotes cancer cell migration via mitogen activated protein kinase activation

Directory of Open Access Journals (Sweden)

Ohannessian Arthur

2004-05-01

Full Text Available Abstract Background Integrin-extracellular matrix interactions activate signaling cascades such as mitogen activated protein kinases (MAPK. Integrin binding to extracellular matrix increases tyrosine phosphorylation of focal adhesion kinase (FAK. Inhibition of FAK activity by expression of its carboxyl terminus decreases cell motility, and cells from FAK deficient mice also show reduced migration. Paxillin is a focal adhesion protein which is also phosphorylated on tyrosine. FAK recruitment of paxillin to the cell membrane correlates with Shc phosphorylation and activation of MAPK. Decreased FAK expression inhibits papilloma formation in a mouse skin carcinogenesis model. We previously demonstrated that MAPK activation was required for growth factor induced in vitro migration and invasion by human squamous cell carcinoma (SCC lines. Methods Adapter protein recruitment to integrin subunits was examined by co-immunoprecipitation in SCC cells attached to type IV collagen or plastic. Stable clones overexpressing FAK or paxillin were created using the lipofection technique. Modified Boyden chambers were used for invasion assays. Results In the present study, we showed that FAK and paxillin but not Shc are recruited to the β1 integrin cytoplasmic domain following attachment of SCC cells to type IV collagen. Overexpression of either FAK or paxillin stimulated cancer cell migration on type IV collagen and invasion through reconstituted basement membrane which was dependent on MAPK activity. Conclusions We concluded that recruitment of focal adhesion kinase and paxillin to β1 integrin promoted cancer cell migration via the mitogen activated protein kinase pathway.

CD4+CD62L+ Central Memory T Cells Can Be Converted to Foxp3+ T Cells

Science.gov (United States)

Zhang, Xiaolong; Chang Li, Xian; Xiao, Xiang; Sun, Rui; Tian, Zhigang; Wei, Haiming

2013-01-01

The peripheral Foxp3+ Treg pool consists of naturally arising Treg (nTreg) and adaptive Treg cells (iTreg). It is well known that naive CD4+ T cells can be readily converted to Foxp3+ iTreg in vitro, and memory CD4+ T cells are resistant to conversion. In this study, we investigated the induction of Foxp3+ T cells from various CD4+ T-cell subsets in human peripheral blood. Though naive CD4+ T cells were readily converted to Foxp3+ T cells with TGF-β and IL-2 treatment in vitro, such Foxp3+ T cells did not express the memory marker CD45RO as do Foxp3+ T cells induced in the peripheral blood of Hepatitis B Virus (HBV) patients. Interestingly, a subset of human memory CD4+ T cells, defined as CD62L+ central memory T cells, could be induced by TGF-β to differentiate into Foxp3+ T cells. It is well known that Foxp3+ T cells derived from human CD4+CD25- T cells in vitro are lack suppressive functions. Our data about the suppressive functions of CD4+CD62L+ central memory T cell-derived Foxp3+ T cells support this conception, and an epigenetic analysis of these cells showed a similar methylation pattern in the FOXP3 Treg-specific demethylated region as the naive CD4+ T cell-derived Foxp3+ T cells. But further research showed that mouse CD4+ central memory T cells also could be induced to differentiate into Foxp3+ T cells, such Foxp3+ T cells could suppress the proliferation of effector T cells. Thus, our study identified CD4+CD62L+ central memory T cells as a novel potential source of iTreg. PMID:24155942

CCL22-specific T Cells

DEFF Research Database (Denmark)

Martinenaite, Evelina; Munir Ahmad, Shamaila; Hansen, Morten

2016-01-01

Tumor cells and tumor-infiltrating macrophages produce the chemokine CCL22, which attracts regulatory T cells (Tregs) into the tumor microenvironment, decreasing anticancer immunity. Here, we investigated the possibility of targeting CCL22-expressing cells by activating specific T cells. We...... analyzed the CCL22 protein signal sequence, identifying a human leukocyte antigen A2- (HLA-A2-) restricted peptide epitope, which we then used to stimulate peripheral blood mononuclear cells (PMBCs) to expand populations of CCL22-specific T cells in vitro. T cells recognizing an epitope derived from...... the signal-peptide of CCL22 will recognize CCL22-expressing cells even though CCL22 is secreted out of the cell. CCL22-specific T cells recognized and killed CCL22-expressing cancer cells. Furthermore, CCL22-specific T cells lysed acute monocytic leukemia cells in a CCL22 expression-dependent manner. Using...

MicroRNA Expression Patterns of CD8+ T Cells in Acute and Chronic Brucellosis

Science.gov (United States)

Budak, Ferah; Bal, S. Haldun; Tezcan, Gulcin; Guvenc, Furkan; Akalin, E. Halis; Goral, Guher; Deniz, Gunnur

2016-01-01

Although our knowledge about Brucella virulence factors and the host response increase rapidly, the mechanisms of immune evasion by the pathogen and causes of chronic disease are still unknown. Here, we aimed to investigate the immunological factors which belong to CD8+ T cells and their roles in the transition of brucellosis from acute to chronic infection. Using miRNA microarray, more than 2000 miRNAs were screened in CD8+ T cells of patients with acute or chronic brucellosis and healthy controls that were sorted from peripheral blood with flow cytometry and validated through qRT-PCR. Findings were evaluated using GeneSpring GX (Agilent) 13.0 software and KEGG pathway analysis. Expression of two miRNAs were determined to display a significant fold change in chronic group when compared with acute or control groups. Both miRNAs (miR-126-5p and miR-4753-3p) were decreased (p 2). These miRNAs have the potential to be the regulators of CD8+ T cell-related marker genes for chronic brucellosis infections. The differentially expressed miRNAs and their predicted target genes are involved in MAPK signaling pathway, cytokine-cytokine receptor interactions, endocytosis, regulation of actin cytoskeleton, and focal adhesion indicating their potential roles in chronic brucellosis and its progression. It is the first study of miRNA expression analysis of human CD8+ T cells to clarify the mechanism of inveteracy in brucellosis. PMID:27824867

Accessory signals in T-T cell interactions between antigen- and alloantigen-specific, human memory T cells generated in vitro

DEFF Research Database (Denmark)

Odum, N; Ryder, L P; Georgsen, J

1990-01-01

The potential of activated HLA class II-positive T cells as antigen-/alloantigen-presenting cells remains controversial. In our model system we use in vitro-primed, HLA class II-specific T cells of the memory T-cell phenotype, CD4+, CD29+ (4B4+), and CD45RO+ (UCHL-1). We have previously shown......), or a calcium ionophore (A23187) enabled Ta to elicit alloantigen-specific memory T-cell responses and to present purified protein derivative (PPD) to PPD-specific T-cell lines. The addition of irradiated, Epstein-Barr virus-transformed B-cell lines (EBV-LCL) (but not their supernatants) had a similar but less...

PROLACTIN-INDUCED TYROSINE PHOSPHORYLATION, ACTIVATION AND RECEPTOR ASSOCIATION OF FOCAL ADHESION KINASE (FAK) IN MAMMARY EPITHELIAL CELLS

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Prolactin-Induced Tyrosine Phosphorylation, Activation and ReceptorAssociation of Focal Adhesion Kinase (FAK) in Mammary Epithelial Cells. Suzanne E. Fenton1 and Lewis G. Sheffield2. 1U.S. Environmental ProtectionAgency, MD-72, Research Triangle Park, NC 27711, and

Mast cells enhance T cell activation: Importance of mast cell-derived TNF

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Nakae, Susumu; Suto, Hajime; Kakurai, Maki; Sedgwick, Jonathon D.; Tsai, Mindy; Galli, Stephen J.

2005-05-01

Mast cells are not only important effector cells in immediate hypersensitivity reactions and immune responses to pathogens but also can contribute to T cell-mediated disorders. However, the mechanisms by which mast cells might influence T cells in such settings are not fully understood. We find that mast cells can enhance proliferation and cytokine production in multiple T cell subsets. Mast cell-dependent enhancement of T cell activation can be promoted by FcRI-dependent mast cell activation, TNF production by both mast cells and T cells, and mast cell-T cell contact. However, at high concentrations of cells, mast cells can promote T cell activation independent of IgE or TNF. Finally, mast cells also can promote T cell activation by means of soluble factors. These findings identify multiple mechanisms by which mast cells can influence T cell proliferation and cytokine production. allergy | asthma | autoimmunity | cytokines | immune response

Introducing micrometer-sized artificial objects into live cells: a method for cell-giant unilamellar vesicle electrofusion.

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Akira C Saito

Full Text Available Here, we report a method for introducing large objects of up to a micrometer in diameter into cultured mammalian cells by electrofusion of giant unilamellar vesicles. We prepared GUVs containing various artificial objects using a water-in-oil (w/o emulsion centrifugation method. GUVs and dispersed HeLa cells were exposed to an alternating current (AC field to induce a linear cell-GUV alignment, and then a direct current (DC pulse was applied to facilitate transient electrofusion. With uniformly sized fluorescent beads as size indexes, we successfully and efficiently introduced beads of 1 µm in diameter into living cells along with a plasmid mammalian expression vector. Our electrofusion did not affect cell viability. After the electrofusion, cells proliferated normally until confluence was reached, and the introduced fluorescent beads were inherited during cell division. Analysis by both confocal microscopy and flow cytometry supported these findings. As an alternative approach, we also introduced a designed nanostructure (DNA origami into live cells. The results we report here represent a milestone for designing artificial symbiosis of functionally active objects (such as micro-machines in living cells. Moreover, our technique can be used for drug delivery, tissue engineering, and cell manipulation.

CXCR5-Dependent Entry of CD8 T Cells into Rhesus Macaque B-Cell Follicles Achieved through T-Cell Engineering.

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Ayala, Victor I; Deleage, Claire; Trivett, Matthew T; Jain, Sumiti; Coren, Lori V; Breed, Matthew W; Kramer, Joshua A; Thomas, James A; Estes, Jacob D; Lifson, Jeffrey D; Ott, David E

2017-06-01

Follicular helper CD4 T cells, T FH , residing in B-cell follicles within secondary lymphoid tissues, are readily infected by AIDS viruses and are a major source of persistent virus despite relative control of viral replication. This persistence is due at least in part to a relative exclusion of effective antiviral CD8 T cells from B-cell follicles. To determine whether CD8 T cells could be engineered to enter B-cell follicles, we genetically modified unselected CD8 T cells to express CXC chemokine receptor 5 (CXCR5), the chemokine receptor implicated in cellular entry into B-cell follicles. Engineered CD8 T cells expressing human CXCR5 (CD8 hCXCR5 ) exhibited ligand-specific signaling and chemotaxis in vitro Six infected rhesus macaques were infused with differentially fluorescent dye-labeled autologous CD8 hCXCR5 and untransduced CD8 T cells and necropsied 48 h later. Flow cytometry of both spleen and lymph node samples revealed higher frequencies of CD8 hCXCR5 than untransduced cells, consistent with preferential trafficking to B-cell follicle-containing tissues. Confocal fluorescence microscopy of thin-sectioned lymphoid tissues demonstrated strong preferential localization of CD8 hCXCR5 T cells within B-cell follicles with only rare cells in extrafollicular locations. CD8 hCXCR5 T cells were present throughout the follicles with some observed near infected T FH In contrast, untransduced CD8 T cells were found in the extrafollicular T-cell zone. Our ability to direct localization of unselected CD8 T cells into B-cell follicles using CXCR5 expression provides a strategy to place highly effective virus-specific CD8 T cells into these AIDS virus sanctuaries and potentially suppress residual viral replication. IMPORTANCE AIDS virus persistence in individuals under effective drug therapy or those who spontaneously control viremia remains an obstacle to definitive treatment. Infected follicular helper CD4 T cells, T FH , present inside B-cell follicles represent a

Tissue engineering and cell-based therapy toward integrated strategy with artificial organs.

Science.gov (United States)

Gojo, Satoshi; Toyoda, Masashi; Umezawa, Akihiro

2011-09-01

Research in order that artificial organs can supplement or completely replace the functions of impaired or damaged tissues and internal organs has been underway for many years. The recent clinical development of implantable left ventricular assist devices has revolutionized the treatment of patients with heart failure. The emerging field of regenerative medicine, which uses human cells and tissues to regenerate internal organs, is now advancing from basic and clinical research to clinical application. In this review, we focus on the novel biomaterials, i.e., fusion protein, and approaches such as three-dimensional and whole-organ tissue engineering. We also compare induced pluripotent stem cells, directly reprogrammed cardiomyocytes, and somatic stem cells for cell source of future cell-based therapy. Integrated strategy of artificial organ and tissue engineering/regenerative medicine should give rise to a new era of medical treatment to organ failure.

T-cell libraries allow simple parallel generation of multiple peptide-specific human T-cell clones.

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Theaker, Sarah M; Rius, Cristina; Greenshields-Watson, Alexander; Lloyd, Angharad; Trimby, Andrew; Fuller, Anna; Miles, John J; Cole, David K; Peakman, Mark; Sewell, Andrew K; Dolton, Garry

2016-03-01

Isolation of peptide-specific T-cell clones is highly desirable for determining the role of T-cells in human disease, as well as for the development of therapies and diagnostics. However, generation of monoclonal T-cells with the required specificity is challenging and time-consuming. Here we describe a library-based strategy for the simple parallel detection and isolation of multiple peptide-specific human T-cell clones from CD8(+) or CD4(+) polyclonal T-cell populations. T-cells were first amplified by CD3/CD28 microbeads in a 96U-well library format, prior to screening for desired peptide recognition. T-cells from peptide-reactive wells were then subjected to cytokine-mediated enrichment followed by single-cell cloning, with the entire process from sample to validated clone taking as little as 6 weeks. Overall, T-cell libraries represent an efficient and relatively rapid tool for the generation of peptide-specific T-cell clones, with applications shown here in infectious disease (Epstein-Barr virus, influenza A, and Ebola virus), autoimmunity (type 1 diabetes) and cancer. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Differentiation, distribution and gammadelta T cell-driven regulation of IL-22-producing T cells in tuberculosis.

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Shuyu Yao

2010-02-01

Full Text Available Differentiation, distribution and immune regulation of human IL-22-producing T cells in infections remain unknown. Here, we demonstrated in a nonhuman primate model that M. tuberculosis infection resulted in apparent increases in numbers of T cells capable of producing IL-22 de novo without in vitro Ag stimulation, and drove distribution of these cells more dramatically in lungs than in blood and lymphoid tissues. Consistently, IL-22-producing T cells were visualized in situ in lung tuberculosis (TB granulomas by confocal microscopy and immunohistochemistry, indicating that mature IL-22-producing T cells were present in TB granuloma. Surprisingly, phosphoantigen HMBPP activation of Vgamma2Vdelta2 T cells down-regulated the capability of T cells to produce IL-22 de novo in lymphocytes from blood, lung/BAL fluid, spleen and lymph node. Up-regulation of IFNgamma-producing Vgamma2Vdelta2 T effector cells after HMBPP stimulation coincided with the down-regulated capacity of these T cells to produce IL-22 de novo. Importantly, anti-IFNgamma neutralizing Ab treatment reversed the HMBPP-mediated down-regulation effect on IL-22-producing T cells, suggesting that Vgamma2Vdelta2 T-cell-driven IFNgamma-networking function was the mechanism underlying the HMBPP-mediated down-regulation of the capability of T cells to produce IL-22. These novel findings raise the possibility to ultimately investigate the function of IL-22 producing T cells and to target Vgamma2Vdelta2 T cells for balancing potentially hyper-activating IL-22-producing T cells in severe TB.

IL-7 and CCL19 expression in CAR-T cells improves immune cell infiltration and CAR-T cell survival in the tumor.

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Adachi, Keishi; Kano, Yosuke; Nagai, Tomohiko; Okuyama, Namiko; Sakoda, Yukimi; Tamada, Koji

2018-04-01

Infiltration, accumulation, and survival of chimeric antigen receptor T (CAR-T) cells in solid tumors is crucial for tumor clearance. We engineered CAR-T cells to express interleukin (IL)-7 and CCL19 (7 × 19 CAR-T cells), as these factors are essential for the maintenance of T-cell zones in lymphoid organs. In mice, 7 × 19 CAR-T cells achieved complete regression of pre-established solid tumors and prolonged mouse survival, with superior anti-tumor activity compared to conventional CAR-T cells. Histopathological analyses showed increased infiltration of dendritic cells (DC) and T cells into tumor tissues following 7 × 19 CAR-T cell therapy. Depletion of recipient T cells before 7 × 19 CAR-T cell administration dampened the therapeutic effects of 7 × 19 CAR-T cell treatment, suggesting that CAR-T cells and recipient immune cells collaborated to exert anti-tumor activity. Following treatment of mice with 7 × 19 CAR-T cells, both recipient conventional T cells and administered CAR-T cells generated memory responses against tumors.

Microglial Cells Prevent Hemorrhage in Neonatal Focal Arterial Stroke.

Science.gov (United States)

Fernández-López, David; Faustino, Joel; Klibanov, Alexander L; Derugin, Nikita; Blanchard, Elodie; Simon, Franziska; Leib, Stephen L; Vexler, Zinaida S

2016-03-09

Perinatal stroke leads to significant morbidity and long-term neurological and cognitive deficits. The pathophysiological mechanisms of brain damage depend on brain maturation at the time of stroke. To understand whether microglial cells limit injury after neonatal stroke by preserving neurovascular integrity, we subjected postnatal day 7 (P7) rats depleted of microglial cells, rats with inhibited microglial TGFbr2/ALK5 signaling, and corresponding controls, to transient middle cerebral artery occlusion (tMCAO). Microglial depletion by intracerebral injection of liposome-encapsulated clodronate at P5 significantly reduced vessel coverage and triggered hemorrhages in injured regions 24 h after tMCAO. Lack of microglia did not alter expression or intracellular redistribution of several tight junction proteins, did not affect degradation of collagen IV induced by the tMCAO, but altered cell types producing TGFβ1 and the phosphorylation and intracellular distribution of SMAD2/3. Selective inhibition of TGFbr2/ALK5 signaling in microglia via intracerebral liposome-encapsulated SB-431542 delivery triggered hemorrhages after tMCAO, demonstrating that TGFβ1/TGFbr2/ALK5 signaling in microglia protects from hemorrhages. Consistent with observations in neonatal rats, depletion of microglia before tMCAO in P9 Cx3cr1(GFP/+)/Ccr2(RFP/+) mice exacerbated injury and induced hemorrhages at 24 h. The effects were independent of infiltration of Ccr2(RFP/+) monocytes into injured regions. Cumulatively, in two species, we show that microglial cells protect neonatal brain from hemorrhage after acute ischemic stroke. Copyright © 2016 the authors 0270-6474/16/362881-13$15.00/0.

T Cell Phenotype and T Cell Receptor Repertoire in Patients with Major Depressive Disorder

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Kostas Patas

2018-02-01

Full Text Available While a link between inflammation and the development of neuropsychiatric disorders, including major depressive disorder (MDD is supported by a growing body of evidence, little is known about the contribution of aberrant adaptive immunity in this context. Here, we conducted in-depth characterization of T cell phenotype and T cell receptor (TCR repertoire in MDD. For this cross-sectional case–control study, we recruited antidepressant-free patients with MDD without any somatic or psychiatric comorbidities (n = 20, who were individually matched for sex, age, body mass index, and smoking status to a non-depressed control subject (n = 20. T cell phenotype and repertoire were interrogated using a combination of flow cytometry, gene expression analysis, and next generation sequencing. T cells from MDD patients showed significantly lower surface expression of the chemokine receptors CXCR3 and CCR6, which are known to be central to T cell differentiation and trafficking. In addition, we observed a shift within the CD4+ T cell compartment characterized by a higher frequency of CD4+CD25highCD127low/− cells and higher FOXP3 mRNA expression in purified CD4+ T cells obtained from patients with MDD. Finally, flow cytometry-based TCR Vβ repertoire analysis indicated a less diverse CD4+ T cell repertoire in MDD, which was corroborated by next generation sequencing of the TCR β chain CDR3 region. Overall, these results suggest that T cell phenotype and TCR utilization are skewed on several levels in patients with MDD. Our study identifies putative cellular and molecular signatures of dysregulated adaptive immunity and reinforces the notion that T cells are a pathophysiologically relevant cell population in this disorder.

Parietal Epithelial Cells Participate in the Formation of Sclerotic Lesions in Focal Segmental Glomerulosclerosis

Science.gov (United States)

Smeets, Bart; Kuppe, Christoph; Sicking, Eva-Maria; Fuss, Astrid; Jirak, Peggy; van Kuppevelt, Toin H.; Endlich, Karlhans; Wetzels, Jack F.M.; Gröne, Hermann-Josef; Floege, Jürgen

2011-01-01

The pathogenesis of the development of sclerotic lesions in focal segmental glomerulosclerosis (FSGS) remains unknown. Here, we selectively tagged podocytes or parietal epithelial cells (PECs) to determine whether PECs contribute to sclerosis. In three distinct models of FSGS (5/6-nephrectomy + DOCA-salt; the murine transgenic chronic Thy1.1 model; or the MWF rat) and in human biopsies, the primary injury to induce FSGS associated with focal activation of PECs and the formation of cellular adhesions to the capillary tuft. From this entry site, activated PECs invaded the affected segment of the glomerular tuft and deposited extracellular matrix. Within the affected segment, podocytes were lost and mesangial sclerosis developed within the endocapillary compartment. In conclusion, these results demonstrate that PECs contribute to the development and progression of the sclerotic lesions that define FSGS, but this pathogenesis may be relevant to all etiologies of glomerulosclerosis. PMID:21719782

ZFAT plays critical roles in peripheral T cell homeostasis and its T cell receptor-mediated response

International Nuclear Information System (INIS)

Doi, Keiko; Fujimoto, Takahiro; Okamura, Tadashi; Ogawa, Masahiro; Tanaka, Yoko; Mototani, Yasumasa; Goto, Motohito; Ota, Takeharu; Matsuzaki, Hiroshi; Kuroki, Masahide; Tsunoda, Toshiyuki; Sasazuki, Takehiko; Shirasawa, Senji

2012-01-01

Highlights: ► We generated Cd4-Cre-mediated T cell-specific Zfat-deficient mice. ► Zfat-deficiency leads to reduction in the number of the peripheral T cells. ► Impaired T cell receptor-mediated response in Zfat-deficient peripheral T cells. ► Decreased expression of IL-7Rα, IL-2Rα and IL-2 in Zfat-deficient peripheral T cells. ► Zfat plays critical roles in peripheral T cell homeostasis. -- Abstract: ZFAT, originally identified as a candidate susceptibility gene for autoimmune thyroid disease, has been reported to be involved in apoptosis, development and primitive hematopoiesis. Zfat is highly expressed in T- and B-cells in the lymphoid tissues, however, its physiological function in the immune system remains totally unknown. Here, we generated the T cell-specific Zfat-deficient mice and demonstrated that Zfat-deficiency leads to a remarkable reduction in the number of the peripheral T cells. Intriguingly, a reduced expression of IL-7Rα and the impaired responsiveness to IL-7 for the survival were observed in the Zfat-deficient T cells. Furthermore, a severe defect in proliferation and increased apoptosis in the Zfat-deficient T cells following T cell receptor (TCR) stimulation was observed with a reduced IL-2Rα expression as well as a reduced IL-2 production. Thus, our findings reveal that Zfat is a critical regulator in peripheral T cell homeostasis and its TCR-mediated response.

Memory T follicular helper CD4 T cells

Directory of Open Access Journals (Sweden)

J. Scott eHale

2015-02-01

Full Text Available T follicular helper (Tfh cells are the subset of CD4 T helper cells that are required for generation and maintenance of germinal center reactions and the generation of long-lived humoral immunity. This specialized T helper subset provides help to cognate B cells via their expression of CD40 ligand, IL-21, IL-4, and other molecules. Tfh cells are characterized by their expression of the chemokine receptor CXCR5, expression of the transcriptional repressor Bcl6, and their capacity to migrate to the follicle and promote germinal center B cell responses. Until recently, it remained unclear whether Tfh cells differentiated into memory cells and whether they maintain their Tfh commitment at the memory phase. This review will highlight several recent studies that support the idea of Tfh-committed CD4 T cells at the memory stage of the immune response. The implication of these findings is that memory Tfh cells retain their capacity to recall their Tfh-specific effector functions upon reactivation to provide help for B cell responses and play an important role in prime and boost vaccination or during recall responses to infection. The markers that are useful for distinguishing Tfh effector and memory cells, as well as the limitations of using these markers will be discussed. Tfh effector and memory generation, lineage maintenance, and plasticity relative to other T helper lineages (Th1, Th2, Th17, etc will also be discussed. Ongoing discoveries regarding the maintenance and lineage stability versus plasticity of memory Tfh cells will improve strategies that utilize CD4 T cell memory to modulate antibody responses during prime and boost vaccination.

Toward angiogenesis of implanted bio-artificial liver using scaffolds with type I collagen and adipose tissue-derived stem cells.

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Lee, Jae Geun; Bak, Seon Young; Nahm, Ji Hae; Lee, Sang Woo; Min, Seon Ok; Kim, Kyung Sik

2015-05-01

Stem cell therapies for liver disease are being studied by many researchers worldwide, but scientific evidence to demonstrate the endocrinologic effects of implanted cells is insufficient, and it is unknown whether implanted cells can function as liver cells. Achieving angiogenesis, arguably the most important characteristic of the liver, is known to be quite difficult, and no practical attempts have been made to achieve this outcome. We carried out this study to observe the possibility of angiogenesis of implanted bio-artificial liver using scaffolds. This study used adipose tissue-derived stem cells that were collected from adult patients with liver diseases with conditions similar to the liver parenchyma. Specifically, microfilaments were used to create an artificial membrane and maintain the structure of an artificial organ. After scratching the stomach surface of severe combined immunocompromised (SCID) mice (n=4), artificial scaffolds with adipose tissue-derived stem cells and type I collagen were implanted. Expression levels of angiogenesis markers including vascular endothelial growth factor (VEGF), CD34, and CD105 were immunohistochemically assessed after 30 days. Grossly, the artificial scaffolds showed adhesion to the stomach and surrounding organs; however, there was no evidence of angiogenesis within the scaffolds; and VEGF, CD34, and CD105 expressions were not detected after 30 days. Although implantation of cells into artificial scaffolds did not facilitate angiogenesis, the artificial scaffolds made with type I collagen helped maintain implanted cells, and surrounding tissue reactions were rare. Our findings indicate that type I collagen artificial scaffolds can be considered as a possible implantable biomaterial.

Focal hypermobility observed in cervical arthroplasty with Mobi-C.

Science.gov (United States)

Kerferd, Jack William; Abi-Hanna, David; Phan, Kevin; Rao, Prashanth; Mobbs, Ralph J

2017-12-01

In recent decades cervical arthroplasty, or cervical disc replacement, has been steadily increasing in popularity as a procedure for the treatment of degenerative pathologies of the cervical spine. This is based on an evolving body of literature that documents superior outcomes in cervical disc replacement over fusion, for both single and double level pathologies, in well selected patients. One of the more recent and popular implants currently on the market is the Mobi-C cervical artificial disc (LDR Medical; Troyes, France). In this paper we report on two cases where focal hypermobility was observed following total disc replacement using the Mobi-C cervical artificial disc. This is followed by a discussion as to potential contributing factors to this hypermobility in relation to both implant design, and operative technique, suggesting potential changes that might prevent this in future patients.

A stromal cell free culture system generates mouse pro-T cells that can reconstitute T-cell compartments in vivo.

Science.gov (United States)

Gehre, Nadine; Nusser, Anja; von Muenchow, Lilly; Tussiwand, Roxane; Engdahl, Corinne; Capoferri, Giuseppina; Bosco, Nabil; Ceredig, Rhodri; Rolink, Antonius G

2015-03-01

T-cell lymphopenia following BM transplantation or diseases such as AIDS result in immunodeficiency. Novel approaches to ameliorate this situation are urgently required. Herein, we describe a novel stromal cell free culture system in which Lineage(-) Sca1(+)c-kit(+) BM hematopoietic progenitors very efficiently differentiate into pro-T cells. This culture system consists of plate-bound Delta-like 4 Notch ligand and the cytokines SCF and IL-7. The pro-T cells developing in these cultures express CD25, CD117, and partially CD44; express cytoplasmic CD3ε; and have their TCRβ locus partially D-J rearranged. They could be expanded for over 3 months and used to reconstitute the T-cell compartments of sublethally irradiated T-cell-deficient CD3ε(-/-) mice or lethally irradiated WT mice. Pro-T cells generated in this system could partially correct the T-cell lymphopenia of pre-Tα(-/-) mice. However, reconstituted CD3ε(-/-) mice suffered from a wasting disease that was prevented by co-injection of purified CD4(+) CD25(high) WT Treg cells. In a T-cell-sufficient or T-lymphopenic setting, the development of disease was not observed. Thus, this in vitro culture system represents a powerful tool to generate large numbers of pro-T cells for transplantation and possibly with clinical applications. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Functional properties of T cells in patients with chronic T gamma lymphocytosis and chronic T cell neoplasia

NARCIS (Netherlands)

Rümke, H. C.; Miedema, F.; ten Berge, I. J.; Terpstra, F.; van der Reijden, H. J.; van de Griend, R. J.; de Bruin, H. G.; von dem Borne, A. E.; Smit, J. W.; Zeijlemaker, W. P.; Melief, C. J.

1982-01-01

The expanded T cell populations of 10 patients with either T gamma lymphocytosis (five patients) or proven chronic T cell malignancy (five patients) were analyzed with respect to functional activity in vitro, including proliferative responses to mitogens, cytotoxic activity (killer [K] and natural

Memory CD8 T cell inflation vs tissue-resident memory T cells: Same patrollers, same controllers?

Science.gov (United States)

Welten, Suzanne P M; Sandu, Ioana; Baumann, Nicolas S; Oxenius, Annette

2018-05-01

The induction of long-lived populations of memory T cells residing in peripheral tissues is of considerable interest for T cell-based vaccines, as they can execute immediate effector functions and thus provide protection in case of pathogen encounter at mucosal and barrier sites. Cytomegalovirus (CMV)-based vaccines support the induction and accumulation of a large population of effector memory CD8 T cells in peripheral tissues, in a process called memory inflation. Tissue-resident memory (T RM ) T cells, induced by various infections and vaccination regimens, constitute another subset of memory cells that take long-term residence in peripheral tissues. Both memory T cell subsets have evoked substantial interest in exploitation for vaccine purposes. However, a direct comparison between these two peripheral tissue-localizing memory T cell subsets with respect to their short- and long-term ability to provide protection against heterologous challenge is pending. Here, we discuss communalities and differences between T RM and inflationary CD8 T cells with respect to their development, maintenance, function, and protective capacity. In addition, we discuss differences and similarities between the transcriptional profiles of T RM and inflationary T cells, supporting the notion that they are distinct memory T cell populations. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

ZFAT plays critical roles in peripheral T cell homeostasis and its T cell receptor-mediated response

Energy Technology Data Exchange (ETDEWEB)

Doi, Keiko [Department of Cell Biology, Faculty of Medicine, Fukuoka University, Fukuoka (Japan); Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka (Japan); Central Research Institute of Life Sciences for the Next Generation of Women Scientists, Fukuoka University, Fukuoka (Japan); Fujimoto, Takahiro [Department of Cell Biology, Faculty of Medicine, Fukuoka University, Fukuoka (Japan); Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka (Japan); Okamura, Tadashi [Division of Animal Models, Department of Infectious Diseases, Research Institute, National Center for Global Health and Medicine, Tokyo (Japan); Ogawa, Masahiro [Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka (Japan); Tanaka, Yoko [Department of Cell Biology, Faculty of Medicine, Fukuoka University, Fukuoka (Japan); Mototani, Yasumasa; Goto, Motohito [Division of Animal Models, Department of Infectious Diseases, Research Institute, National Center for Global Health and Medicine, Tokyo (Japan); Ota, Takeharu; Matsuzaki, Hiroshi [Department of Cell Biology, Faculty of Medicine, Fukuoka University, Fukuoka (Japan); Kuroki, Masahide [Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka (Japan); Tsunoda, Toshiyuki [Department of Cell Biology, Faculty of Medicine, Fukuoka University, Fukuoka (Japan); Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka (Japan); Sasazuki, Takehiko [Institute for Advanced Study, Kyushu University, Fukuoka (Japan); Shirasawa, Senji, E-mail: sshirasa@fukuoka-u.ac.jp [Department of Cell Biology, Faculty of Medicine, Fukuoka University, Fukuoka (Japan); Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka (Japan)

2012-08-17

Highlights: Black-Right-Pointing-Pointer We generated Cd4-Cre-mediated T cell-specific Zfat-deficient mice. Black-Right-Pointing-Pointer Zfat-deficiency leads to reduction in the number of the peripheral T cells. Black-Right-Pointing-Pointer Impaired T cell receptor-mediated response in Zfat-deficient peripheral T cells. Black-Right-Pointing-Pointer Decreased expression of IL-7R{alpha}, IL-2R{alpha} and IL-2 in Zfat-deficient peripheral T cells. Black-Right-Pointing-Pointer Zfat plays critical roles in peripheral T cell homeostasis. -- Abstract: ZFAT, originally identified as a candidate susceptibility gene for autoimmune thyroid disease, has been reported to be involved in apoptosis, development and primitive hematopoiesis. Zfat is highly expressed in T- and B-cells in the lymphoid tissues, however, its physiological function in the immune system remains totally unknown. Here, we generated the T cell-specific Zfat-deficient mice and demonstrated that Zfat-deficiency leads to a remarkable reduction in the number of the peripheral T cells. Intriguingly, a reduced expression of IL-7R{alpha} and the impaired responsiveness to IL-7 for the survival were observed in the Zfat-deficient T cells. Furthermore, a severe defect in proliferation and increased apoptosis in the Zfat-deficient T cells following T cell receptor (TCR) stimulation was observed with a reduced IL-2R{alpha} expression as well as a reduced IL-2 production. Thus, our findings reveal that Zfat is a critical regulator in peripheral T cell homeostasis and its TCR-mediated response.

Effects of topical cyclosporine a plus artificial tears versus artificial tears treatment on conjunctival goblet cell density in dysfunctional tear syndrome.

Science.gov (United States)

Demiryay, Elvan; Yaylali, Volkan; Cetin, Ebru Nevin; Yildirim, Cem

2011-09-01

The aim was to compare the effects of topical cyclosporine A and artificial tears combination with artificial tears alone in patients with dysfunctional tear syndrome (DTS). Forty-two eyes of 42 patients with DTS were enrolled in the study. The inclusion criteria for the study were Schirmer I (without anesthesia) scores below 10 mm/5 min and tear film break-up time (BUT) below 10 sec. The patients were randomly divided into two groups. The study group (22 patients) underwent 0.05% cyclosporine A treatment twice a day and preservative-free artificial tears for four times a day for 4 months. The control group (20 patients) was administered only preservative-free artificial tears four times a day for 4 months. The BUT, Schirmer test scores, corneal fluorescein staining, conjunctival lissamine green staining, and goblet cell density derived by impression cytology were recorded before and after treatment in each group. In the study group, all parameters improved statistically significantly after treatment at the 4-month follow-up compared with the pretreatment values (Ptears treatment significantly increases goblet cell density, decreases the signs of DTS, and improves ocular surface health.

Effects of X-irradiation on artificial blood vessel wall degradation by invasive tumor cells

International Nuclear Information System (INIS)

Heisel, M.A.; Laug, W.E.; Stowe, S.M.; Jones, P.A.

1984-01-01

Artificial vessel wall cultures, constructed by growing arterial endothelial cells on preformed layers of rat smooth muscle cells, were used to evaluate the effects of X-irradiation on tumor cell-induced tissue degradation. Bovine endothelial cells had radiation sensitivities similar to those of rat smooth muscle cells. Preirradiation of smooth muscle cells, before the addition of human fibrosarcoma (HT 1080) cells, did not increase the rate of degradation and destruction by the invasive cells. However, the degradation rate was decreased if the cultures were irradiated after the addition of HT 1080 cells. The presence of bovine endothelial cells markedly inhibited the destructive abilities of fibrosarcoma cells, but preirradiation of artificial vessel walls substantially decreased their capabilities to resist HT 1080-induced lysis. These findings suggest that the abilities of blood vessels to limit extravasation may be compromised by ionizing radiation

MRI of focal cortical dysplasia

International Nuclear Information System (INIS)

Lee, B.C.P.; Hatfield, G.A.; Bourgeois, B.; Park, T.S.

1998-01-01

We studied nine cases of focal cortical dysplasia (FCD) by MRI, with surface-rendered 3D reconstructions. One case was also examined using single-voxel proton MR spectroscopy (MRS). The histological features were reviewed and correlated with the MRI findings. The gyri affected by FCD were enlarged and the signal of the cortex was slightly increased on T1-weighted images. The gray-white junction was indistinct. Signal from the subcortical white matter was decreased on T1- and increased on T2-weighted images in most cases. Contrast enhancement was seen in two cases. Proton MRS showed a spectrum identical to that of normal brain. (orig.) (orig.)

Butterfly Wings Are Three-Dimensional: Pupal Cuticle Focal Spots and Their Associated Structures in Junonia Butterflies.

Science.gov (United States)

Taira, Wataru; Otaki, Joji M

2016-01-01

Butterfly wing color patterns often contain eyespots, which are developmentally determined at the late larval and early pupal stages by organizing activities of focal cells that can later form eyespot foci. In the pupal stage, the focal position of a future eyespot is often marked by a focal spot, one of the pupal cuticle spots, on the pupal surface. Here, we examined the possible relationships of the pupal focal spots with the underneath pupal wing tissues and with the adult wing eyespots using Junonia butterflies. Large pupal focal spots were found in two species with large adult eyespots, J. orithya and J. almana, whereas only small pupal focal spots were found in a species with small adult eyespots, J. hedonia. The size of five pupal focal spots on a single wing was correlated with the size of the corresponding adult eyespots in J. orithya. A pupal focal spot was a three-dimensional bulge of cuticle surface, and the underside of the major pupal focal spot exhibited a hollowed cuticle in a pupal case. Cross sections of a pupal wing revealed that the cuticle layer shows a curvature at a focal spot, and a positional correlation was observed between the cuticle layer thickness and its corresponding cell layer thickness. Adult major eyespots of J. orithya and J. almana exhibited surface elevations and depressions that approximately correspond to the coloration within an eyespot. Our results suggest that a pupal focal spot is produced by the organizing activity of focal cells underneath the focal spot. Probably because the focal cell layer immediately underneath a focal spot is thicker than that of its surrounding areas, eyespots of adult butterfly wings are three-dimensionally constructed. The color-height relationship in adult eyespots might have an implication in the developmental signaling for determining the eyespot color patterns.

Butterfly Wings Are Three-Dimensional: Pupal Cuticle Focal Spots and Their Associated Structures in Junonia Butterflies.

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Wataru Taira

Full Text Available Butterfly wing color patterns often contain eyespots, which are developmentally determined at the late larval and early pupal stages by organizing activities of focal cells that can later form eyespot foci. In the pupal stage, the focal position of a future eyespot is often marked by a focal spot, one of the pupal cuticle spots, on the pupal surface. Here, we examined the possible relationships of the pupal focal spots with the underneath pupal wing tissues and with the adult wing eyespots using Junonia butterflies. Large pupal focal spots were found in two species with large adult eyespots, J. orithya and J. almana, whereas only small pupal focal spots were found in a species with small adult eyespots, J. hedonia. The size of five pupal focal spots on a single wing was correlated with the size of the corresponding adult eyespots in J. orithya. A pupal focal spot was a three-dimensional bulge of cuticle surface, and the underside of the major pupal focal spot exhibited a hollowed cuticle in a pupal case. Cross sections of a pupal wing revealed that the cuticle layer shows a curvature at a focal spot, and a positional correlation was observed between the cuticle layer thickness and its corresponding cell layer thickness. Adult major eyespots of J. orithya and J. almana exhibited surface elevations and depressions that approximately correspond to the coloration within an eyespot. Our results suggest that a pupal focal spot is produced by the organizing activity of focal cells underneath the focal spot. Probably because the focal cell layer immediately underneath a focal spot is thicker than that of its surrounding areas, eyespots of adult butterfly wings are three-dimensionally constructed. The color-height relationship in adult eyespots might have an implication in the developmental signaling for determining the eyespot color patterns.

Ability of γδ T cells to modulate the Foxp3 T cell response is dependent on adenosine.

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Dongchun Liang

Full Text Available Whether γδ T cells inhibit or enhance the Foxp3 T cell response depends upon their activation status. The critical enhancing effector in the supernatant is adenosine. Activated γδ T cells express adenosine receptors at high levels, which enables them to deprive Foxp3+ T cells of adenosine, and to inhibit their expansion. Meanwhile, cell-free supernatants of γδ T cell cultures enhance Foxp3 T cell expansion. Thus, inhibition and enhancement by γδ T cells of Foxp3 T cell response are a reflection of the balance between adenosine production and absorption by γδ T cells. Non-activated γδ T cells produce adenosine but bind little, and thus enhance the Foxp3 T cell response. Activated γδ T cells express high density of adenosine receptors and have a greatly increased ability to bind adenosine. Extracellular adenosine metabolism and expression of adenosine receptor A2ARs by γδ T cells played a major role in the outcome of γδ and Foxp3 T cell interactions. A better understanding of the functional conversion of γδ T cells could lead to γδ T cell-targeted immunotherapies for related diseases.

Tunable swelling of polyelectrolyte multilayers in cell culture media for modulating NIH-3T3 cells adhesion.

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Qi, Wei; Cai, Peng; Yuan, Wenjing; Wang, Hua

2014-11-01

For polyelectrolyte multilayers (PEMs) assembled by the layer-by-layer (LbL) assembly technique, their nanostructure and properties can be governed by many parameters during the building process. Here, it was demonstrated that the swelling of the PEMs containing poly(diallyldimethylammonium chloride) (PDDA) and poly(sodium 4-styrenesulfonate) (PSS) in cell culture media could be tuned with changing supporting salt solutions during the assembly process. Importantly, the influence of the PEMs assembled in different salt solutions on NIH-3T3 cell adhesion was observable. Specifically, the cells could possess a higher affinity for the films assembled in low salt concentration (i.e. 0.15M NaCl) or no salt, the poorly swelling films in cell culture media, which was manifested by the large cell spreading area and focal adhesions. In contrast, those were assembled in higher salt concentration, highly swelling films in cell culture media, were less attractive for the fibroblasts. As a result, the cell adhesion behaviors may be manipulated by tailoring the physicochemical properties of the films, which could be performed by changing the assembly conditions such as supporting salt concentration. Such a finding might promise a great potential in designing desired biomaterials for tissue engineering and regenerative medicine. © 2014 Wiley Periodicals, Inc.

Contrubución de la técnica del grupo focal al acercamiento a la percepción estudiantil sobre accesibilidad en el entorno universitario

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Gross Martínez, Martha

2015-01-01

Full Text Available Este artículo describe la técnica de grupo focal utilizada en la investigación: “Accesibilidad en la permanencia de estudiantes con necesidades educativas asociadas o no a discapacidad: Sede Rodrigo Facio” de la Universidad de Costa Rica; cuyo objetivo general consistió en la elaboración de una guía de comprobación y buenas prácticas en el tema de accesibilidad, como un recurso que le permita a la comunidad universitaria dar respuesta a esta población y constituirse en insumo para la construcción de una universidad inclusiva. A partir de los grupos focales, se exploró la percepción estudiantil con necesidades educativas asociadas o no a discapacidad, sobre la accesibilidad en la vida universitaria; para ello esta se caracterizó y categorizó en tres dimensiones: accesibilidad al espacio físico, a la información y al proceso educativo. Esta técnica permitió que cada participante expresara sus percepciones, comentara su vivencia e interacción con el entorno universitario. Finalmente, se concluye que los grupos focales constituyen una técnica relevante de recolección de información en los procesos de investigación cualitativa, porque establecen un acercamiento personal, lo que la convierte en un recurso útil para conocer a esta población

Selective T-cell depletion targeting CD45RA reduces viremia and enhances early T-cell recovery compared with CD3-targeted T-cell depletion.

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Triplett, Brandon M; Muller, Brad; Kang, Guolian; Li, Ying; Cross, Shane J; Moen, Joseph; Cunningham, Lea; Janssen, William; Mamcarz, Ewelina; Shook, David R; Srinivasan, Ashok; Choi, John; Hayden, Randall T; Leung, Wing

2018-02-01

T-cell depletion (TCD) effectively reduces severe graft-versus-host disease in recipients of HLA-mismatched allografts. However, TCD is associated with delayed immune recovery and increased infections. We hypothesized that specific depletion of CD45RA+ naive T cells, rather than broad depletion of CD3+ T cells, can preserve memory-immunity in the allografts and confer protection against important viral infections in the early post-transplant period. Sixty-seven patients who received TCD haploidentical donor transplantation for hematologic malignancy on 3 consecutive trials were analyzed. Patients receiving CD45RA-depleted donor grafts had 2000-fold more donor T cells infused, significantly higher T-cell counts at Day +30 post transplant (550/μL vs 10/μL; P depleted grafts were more likely to experience adenovirus viremia (27% vs 4%, P = .02). CD45RA-depletion provided a large number of donor memory T cells to the recipients and was associated with enhanced early T-cell recovery and protection against viremia. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

T cell clones which share T cell receptor epitopes differ in phenotype, function and specificity

NARCIS (Netherlands)

Yssel, H.; Blanchard, D.; Boylston, A.; de Vries, J. E.; Spits, H.

1986-01-01

Recently, we described a monoclonal antibody (3D6) that reacts with the T cell receptor (Ti) of the T leukemic cell line HPB-ALL and that cross-reacts with 2-10% of the T cells of normal healthy individuals. In this study we report the establishment of T cell clones that are 3D6+ but that differ in

Can resting B cells present antigen to T cells

International Nuclear Information System (INIS)

Ashwell, J.D.; DeFranco, A.L.; Paul, W.E.; Schwartz, R.H.

1985-01-01

Antigen stimulation of T lymphocytes can occur only in the presence of an antigen-presenting cell (APC). An ever-increasing number of cell types have been found to act as APCs; these include macrophages, splenic and lymph node dendritic cells, and Langerhans cells of the skin. Although activated B lymphocytes and B cell lymphomas are known to serve as APCs, it has been generally believed that resting B cells cannot perform this function. However, in recent studies the authors have found that resting B cells can indeed present soluble antigen to T cell clones as well as to antigen-primed T cells. The previous difficulty in demonstrating this activity can be explained by the finding that, in contrast to macrophages and dendritic cells, the antigen-presenting ability of resting B cells is very radiosensitive. Macrophages are usually irradiated with 2000-3300 rads to prevent them from incorporating [ 3 H]thymidine in the T cell proliferation assay. Resting B cells, however, begin to lose presenting function at 1500 rads and have completely lost this activity at 3300 rads. It was also possible to distinguish two distinct T cell clonal phenotypes when resting B cells were used as APCs on the basis of two different assays (T cell proliferation, and B cell proliferation resulting from T cell activation). The majority of T cell clones tested were capable of both proliferating themselves and inducing the proliferation of B cells. Some T cells clones, however, could not proliferate in the presence of antigen and B cell APCs, although they were very good at inducing the proliferation of B cells

MS4a4B, a CD20 homologue in T cells, inhibits T cell propagation by modulation of cell cycle.

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Hui Xu

2010-11-01

Full Text Available MS4a4B, a CD20 homologue in T cells, is a novel member of the MS4A gene family in mice. The MS4A family includes CD20, FcεRIβ, HTm4 and at least 26 novel members that are characterized by their structural features: with four membrane-spanning domains, two extracellular domains and two cytoplasmic regions. CD20, FcεRIβ and HTm4 have been found to function in B cells, mast cells and hematopoietic cells respectively. However, little is known about the function of MS4a4B in T cell regulation. We demonstrate here that MS4a4B negatively regulates mouse T cell proliferation. MS4a4B is highly expressed in primary T cells, natural killer cells (NK and some T cell lines. But its expression in all malignant T cells, including thymoma and T hybridoma tested, was silenced. Interestingly, its expression was regulated during T cell activation. Viral vector-driven overexpression of MS4a4B in primary T cells and EL4 thymoma cells reduced cell proliferation. In contrast, knockdown of MS4a4B accelerated T cell proliferation. Cell cycle analysis showed that MS4a4B regulated T cell proliferation by inhibiting entry of the cells into S-G2/M phase. MS4a4B-mediated inhibition of cell cycle was correlated with upregulation of Cdk inhibitory proteins and decreased levels of Cdk2 activity, subsequently leading to inhibition of cell cycle progression. Our data indicate that MS4a4B negatively regulates T cell proliferation. MS4a4B, therefore, may serve as a modulator in the negative-feedback regulatory loop of activated T cells.

MS4a4B, a CD20 homologue in T cells, inhibits T cell propagation by modulation of cell cycle.

Science.gov (United States)

Xu, Hui; Yan, Yaping; Williams, Mark S; Carey, Gregory B; Yang, Jingxian; Li, Hongmei; Zhang, Guang-Xian; Rostami, Abdolmohamad

2010-11-01

MS4a4B, a CD20 homologue in T cells, is a novel member of the MS4A gene family in mice. The MS4A family includes CD20, FcεRIβ, HTm4 and at least 26 novel members that are characterized by their structural features: with four membrane-spanning domains, two extracellular domains and two cytoplasmic regions. CD20, FcεRIβ and HTm4 have been found to function in B cells, mast cells and hematopoietic cells respectively. However, little is known about the function of MS4a4B in T cell regulation. We demonstrate here that MS4a4B negatively regulates mouse T cell proliferation. MS4a4B is highly expressed in primary T cells, natural killer cells (NK) and some T cell lines. But its expression in all malignant T cells, including thymoma and T hybridoma tested, was silenced. Interestingly, its expression was regulated during T cell activation. Viral vector-driven overexpression of MS4a4B in primary T cells and EL4 thymoma cells reduced cell proliferation. In contrast, knockdown of MS4a4B accelerated T cell proliferation. Cell cycle analysis showed that MS4a4B regulated T cell proliferation by inhibiting entry of the cells into S-G2/M phase. MS4a4B-mediated inhibition of cell cycle was correlated with upregulation of Cdk inhibitory proteins and decreased levels of Cdk2 activity, subsequently leading to inhibition of cell cycle progression. Our data indicate that MS4a4B negatively regulates T cell proliferation. MS4a4B, therefore, may serve as a modulator in the negative-feedback regulatory loop of activated T cells.

CD4+ T cell-derived novel peptide Thp5 induces interleukin-4 production in CD4+ T cells to direct T helper 2 cell differentiation.

Science.gov (United States)

Khan, Mohd Moin; Chatterjee, Samit; Dwivedi, Ved Prakash; Pandey, Nishant Kumar; Singh, Yogesh; Tousif, Sultan; Bhavesh, Neel Sarovar; Van Kaer, Luc; Das, Jyoti; Das, Gobardhan

2012-01-20

The differentiation of naïve CD4(+) T cells into T helper 2 (Th2) cells requires production of the cytokine IL-4 in the local microenvironment. It is evident that naïve/quiescently activated CD4(+) T cells produce the IL-4 that drives Th2 cell differentiation. Because early production of IL-4 in naïve T cells leads to preferential Th2 cell differentiation, this process needs to be tightly regulated so as to avoid catastrophic and misdirected Th2 cell differentiation. Here, we show that Thp5, a novel peptide with structural similarity to vasoactive intestinal peptide, regulates production of early IL-4 in newly activated CD4(+) T cells. Induction of IL-4 in CD4(+) T cells by Thp5 is independent of the transcription factor STAT6 but dependent on ERK1/2 signaling. Furthermore, cytokines (IL-12 and TGF-β) that promote the differentiation of Th1 or Th17 cells inhibit Thp5 induction, thus suppressing Th2 cell differentiation. We further showed that Thp5 enhances Th2 responses and exacerbates allergic airway inflammation in mice. Taken together, our findings reveal that early activated CD4(+) T cells produce Thp5, which plays a critical role as a molecular switch in the differentiation of Th cells, biasing the response toward the Th2 cell phenotype.

[gammadelta T cells stimulated by zoledronate kill osteosarcoma cells].

Science.gov (United States)

Jiang, Hui; Xu, Qiang; Yang, Chao; Cao, Zhen-Guo; Li, Zhao-Xu; Ye, Zhao-Ming

2010-12-01

To investigate the cytotoxicity of human γδT cells from PBMCs stimulated by zoledronate against osteosarcoma cell line HOS in vitro and in vivo and evaluate the relavent pathways. The peripheral blood mononuclear cells (PBMCs)of healthy donors were stimulated by single dose zoledronate and cultured in the present of IL-2 for two weeks, analysising the percentage of γδT cells on a FACSCalibur cytometer.Study the cytotoxicity of γδT cells against the osteosarcoma line HOS using LDH release assay kit. Pre-treatment of γδT cells with anti-human γδTCR antibody, anti-human NKG2D antibody and concanamycin A to bolck the relavent pathways for evaluating the mechenisms of its cytotoxicity. In vivo, BALB/c mice were inoculated subcutaneously osteosarcoma cell HOS for developing hypodermal tumors. And they were randomized into two groups: unteated group, γδT cell therapy group. Tumor volume and weight of the two groups were compared. After two weeks of culture, γδT cells from zoledronate-stimulated PBMCs could reach (95±3)%. When the E:T as 6:1, 12:1, 25:1, 50:1, the percentage of osteosarcoma cell HOS killed by γδT cells was 26.8%, 31.5%, 37.8%, 40.9%, respectively.When anti-huma γδTCR antibody, anti-human NKG2D antibody and concanamycin A blocked the relavent pathways, the percentage was 32.3%, 4.7%, 16.7% ( E:T as 25:1), respectively. In vivo, the tumor inhibition rate of the group of γδT cell therapy was 42.78%. γδT cells derived from PBMCs stimulated by zoledronate can acquired pure γδT cells. And they show strong cytoxicity against osteosarcoma cell line HOS in vitro and in vivo.

Primary focal T-cell lymphoma of the liver: a case report and review of the literature.

Science.gov (United States)

Cerban, Razvan; Gheorghe, Liana; Becheanu, Gabriel; Serban, Valentin; Gheorghe, Cristian

2012-06-01

We present the case of a previously healthy 62 year old man who developed primary non-Hodgkin lymphoma of the liver. Biopsy confirmed that it was a diffuse large anaplastic T-cell lymphoma of an extremely rare type. The diagnosis of this type of lesions is suggested by the presence of a hepatic mass without lymphadenopathy, splenomegaly or bone marrow involvement associated with normal tumor markers (carcinoembryonic antigen, alpha-fetoprotein and CA 19-9 levels). Histological examination of tissue is essential to confirm the diagnosis. Treatment options are surgical resection and/or chemotherapy but the rate of response to treatment varies widely. Some patients can achieve prolonged remission.

Special regulatory T-cell review: T-cell dependent suppression revisited.

Science.gov (United States)

Basten, Antony; Fazekas de St Groth, Barbara

2008-01-01

The concept of T-cell dependent regulation of immune responses has been a central tenet of immunological thinking since the delineation of the two cell system in the 1960s. Indeed T-cell dependent suppression was discovered before MHC restriction. When reviewing the data from the original wave of suppression, it is intriguing to reflect not just on the decline and fall of suppressor T cells in the 1980s, but on their equally dramatic return to respectability over the past decade. Hopefully their resurgence will be supported by solid mechanistic data that will underpin their central place in our current and future understanding of the immune system. Cannon to right of them, Cannon to left of them, Cannon in front of them Volley'd and thunder'd Storm'd at with shot and shell, Boldly they rode and well, Into the jaws of Death, Into the mouth of Hell, Rode the six hundred (suppressionists). (Adapted from The Charge of the Light Brigade, Alfred, Lord Tennyson)

Membrane-bound Dickkopf-1 in Foxp3+ regulatory T cells suppresses T-cell-mediated autoimmune colitis.

Science.gov (United States)

Chae, Wook-Jin; Park, Jong-Hyun; Henegariu, Octavian; Yilmaz, Saliha; Hao, Liming; Bothwell, Alfred L M

2017-10-01

Induction of tolerance is a key mechanism to maintain or to restore immunological homeostasis. Here we show that Foxp3 + regulatory T (Treg) cells use Dickkopf-1 (DKK-1) to regulate T-cell-mediated tolerance in the T-cell-mediated autoimmune colitis model. Treg cells from DKK-1 hypomorphic doubleridge mice failed to control CD4 + T-cell proliferation, resulting in CD4 T-cell-mediated autoimmune colitis. Thymus-derived Treg cells showed a robust expression of DKK-1 but not in naive or effector CD4 T cells. DKK-1 expression in Foxp3 + Treg cells was further increased upon T-cell receptor stimulation in vitro and in vivo. Interestingly, Foxp3 + Treg cells expressed DKK-1 in the cell membrane and the functional inhibition of DKK-1 using DKK-1 monoclonal antibody abrogated the suppressor function of Foxp3 + Treg cells. DKK-1 expression was dependent on de novo protein synthesis and regulated by the mitogen-activated protein kinase pathway but not by the canonical Wnt pathway. Taken together, our results highlight membrane-bound DKK-1 as a novel Treg-derived mediator to maintain immunological tolerance in T-cell-mediated autoimmune colitis. © 2017 The Authors. Immunology Published by John Wiley & Sons Ltd.

Expansion of mycobacterium-reactive gamma delta T cells by a subset of memory helper T cells.

Science.gov (United States)

Vila, L M; Haftel, H M; Park, H S; Lin, M S; Romzek, N C; Hanash, S M; Holoshitz, J

1995-04-01

Human gamma delta T cells expressing the V gamma 9/V delta 2 T-cell receptor have been previously found to proliferate in response to certain microorganisms and to expand throughout life, presumably because of extrathymic activation by foreign antigens. In vitro expansion of V gamma 9/V delta 2 cells by mycobacteria has been previously shown to be dependent on accessory cells. In order to gain an insight into the mechanisms involved in the expansion of these cells, we have undertaken to identify the peripheral blood subset of cells on which proliferation of V gamma 9/V delta 2 cells in response to mycobacteria is dependent. Contrary to their role in antigen presentation to alpha beta T cells, professional antigen-presenting cells, such as monocytes, B cells, and dendritic cells, were unable to provide the cellular support for the expansion of V gamma 9/V delta 2 cells. Selective depletion of T-cell subsets, as well as the use of highly purified T-cell populations, indicated that the only subset of peripheral blood cells that could expand V gamma 9/V delta 2 cells were CD4+ CD45RO+ CD7- alpha beta T cells. These cells underwent distinct intracellular signaling events after stimulation with the mycobacterial antigen. Expansion of V gamma 9/V delta 2 cells by alpha beta T cells was dependent on cell-cell contact. This is the first evidence that a small subset of the memory helper T-cell population is exclusively responsible for the peripheral expansion of V gamma 9/V delta 2 cells. These data illustrate a unique aspect of antigen recognition by gamma delta T cells and provide new means to study their immune defense role.

Evaluation of accessory cell heterogeneity. I. Differential accessory cell requirement for T helper cell activation and for T-B cooperation.

Science.gov (United States)

Ramila, G; Studer, S; Kennedy, M; Sklenar, I; Erb, P

1985-01-01

Several Ia+ tumor cell lines and peritoneal exudate macrophages were tested as accessory cells (AC) for the activation of antigen-specific T cells and for T-B cooperation. The macrophages and all the Ia+ tumor lines tested induced the release of lymphokines from T cells in a major histocompatibility complex (MHC)-restricted fashion and reconstituted the antibody responses of AC-depleted spleen cells or of purified T and B cells. However, only the normal macrophages but none of the tumor lines induced carrier-specific T helper (Th) cells which help B cells for specific antihapten antibody responses by linked recognition. For T-B cooperation accessory cells were also required, but in contrast to Th cell activation any type of Ia+ AC (e.g. macrophage or tumor line) was effective. Strong MHC-restriction between the lymphocytes and the AC was seen if antigen-pulsed AC were added into the AC-depleted T-B cooperation cultures. If the AC and antigen were concomitantly added to the AC-depleted T-B cultures, MHC-restriction was less obvious. Concanavalin A supernatant reconstituted the response of AC-depleted T-B cultures provided antigen-specific Th cells and the hapten-carrier conjugate were present. If, however, tumor line-activated T cells were added instead of macrophage-induced Th cells, no cooperation with B cells took place even in the presence of Con A supernatant. The results obtained demonstrate a differential AC requirement for the induction of Th cells depending on the differentiation stage of the Th cells.

Focal adhesions, stress fibers and mechanical tension

Energy Technology Data Exchange (ETDEWEB)

Burridge, Keith, E-mail: Keith_Burridge@med.unc.edu [Department of Cell Biology and Physiology, and Lineberger Comprehensive Cancer Center, 12-016 Lineberger, CB#7295, University of North Carolina, Chapel Hill, NC (United States); Guilluy, Christophe, E-mail: christophe.guilluy@univ-nantes.fr [Inserm UMR-S1087, CNRS UMR-C6291, L' institut du Thorax, and Université de Nantes, Nantes (France)

2016-04-10

Stress fibers and focal adhesions are complex protein arrays that produce, transmit and sense mechanical tension. Evidence accumulated over many years led to the conclusion that mechanical tension generated within stress fibers contributes to the assembly of both stress fibers themselves and their associated focal adhesions. However, several lines of evidence have recently been presented against this model. Here we discuss the evidence for and against the role of mechanical tension in driving the assembly of these structures. We also consider how their assembly is influenced by the rigidity of the substratum to which cells are adhering. Finally, we discuss the recently identified connections between stress fibers and the nucleus, and the roles that these may play, both in cell migration and regulating nuclear function. - Highlights: • The different types of stress fiber and focal adhesion are described. • We discuss the controversy about tension and assembly of these structures. • We describe the different models used to investigate assembly of these structures. • The influence of substratum rigidity is discussed. • Stress fiber connections to the nucleus are reviewed.

Redirecting T cells to eradicate B-cell acute lymphoblastic leukemia: bispecific T-cell engagers and chimeric antigen receptors.

Science.gov (United States)

Aldoss, I; Bargou, R C; Nagorsen, D; Friberg, G R; Baeuerle, P A; Forman, S J

2017-04-01

Recent advances in antibody technology to harness T cells for cancer immunotherapy, particularly in the difficult-to-treat setting of relapsed/refractory acute lymphoblastic leukemia (r/r ALL), have led to innovative methods for directing cytotoxic T cells to specific surface antigens on cancer cells. One approach involves administration of soluble bispecific (or dual-affinity) antibody-based constructs that temporarily bridge T cells and cancer cells. Another approach infuses ex vivo-engineered T cells that express a surface plasma membrane-inserted antibody construct called a chimeric antigen receptor (CAR). Both bispecific antibodies and CARs circumvent natural target cell recognition by creating a physical connection between cytotoxic T cells and target cancer cells to activate a cytolysis signaling pathway; this connection allows essentially all cytotoxic T cells in a patient to be engaged because typical tumor cell resistance mechanisms (such as T-cell receptor specificity, antigen processing and presentation, and major histocompatibility complex context) are bypassed. Both the bispecific T-cell engager (BiTE) antibody construct blinatumomab and CD19-CARs are immunotherapies that have yielded encouraging remission rates in CD19-positive r/r ALL, suggesting that they might serve as definitive treatments or bridging therapies to allogeneic hematopoietic cell transplantation. With the introduction of these immunotherapies, new challenges arise related to unique toxicities and distinctive pathways of resistance. An increasing body of knowledge is being accumulated on how to predict, prevent, and manage such toxicities, which will help to better stratify patient risk and tailor treatments to minimize severe adverse events. A deeper understanding of the precise mechanisms of action and immune resistance, interaction with other novel agents in potential combinations, and optimization in the manufacturing process will help to advance immunotherapy outcomes in the r

γδ T cells producing interleukin-17A regulate adipose regulatory T cell homeostasis and thermogenesis.

Science.gov (United States)

Kohlgruber, Ayano C; Gal-Oz, Shani T; LaMarche, Nelson M; Shimazaki, Moto; Duquette, Danielle; Nguyen, Hung N; Mina, Amir I; Paras, Tyler; Tavakkoli, Ali; von Andrian, Ulrich; Banks, Alexander S; Shay, Tal; Brenner, Michael B; Lynch, Lydia

2018-05-01

γδ T cells are situated at barrier sites and guard the body from infection and damage. However, little is known about their roles outside of host defense in nonbarrier tissues. Here, we characterize a highly enriched tissue-resident population of γδ T cells in adipose tissue that regulate age-dependent regulatory T cell (T reg ) expansion and control core body temperature in response to environmental fluctuations. Mechanistically, innate PLZF + γδ T cells produced tumor necrosis factor and interleukin (IL) 17 A and determined PDGFRα + and Pdpn + stromal-cell production of IL-33 in adipose tissue. Mice lacking γδ T cells or IL-17A exhibited decreases in both ST2 + T reg cells and IL-33 abundance in visceral adipose tissue. Remarkably, these mice also lacked the ability to regulate core body temperature at thermoneutrality and after cold challenge. Together, these findings uncover important physiological roles for resident γδ T cells in adipose tissue immune homeostasis and body-temperature control.

Antigen-specific T cell activation independently of the MHC: chimeric antigen receptor (CAR-redirected T cells.

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Hinrich eAbken

2013-11-01

Full Text Available Adoptive T cell therapy has recently shown powerful in initiating a lasting anti-tumor response with spectacular therapeutic success in some cases. Specific T cell therapy, however, is limited since a number of cancer cells are not recognized by T cells due to various mechanisms including the limited availability of tumor-specific T cells and deficiencies in antigen processing or major histocompatibility complex (MHC expression of cancer cells. To make adoptive cell therapy applicable for the broad variety of cancer entities, patient's T cells are engineered ex vivo with pre-defined specificity by a recombinant chimeric antigen receptor (CAR which consists in the extracellular part of an antibody-derived domain for binding with a tumor-associated antigen and in the intracellular part of a TCR-derived signaling moiety for T cell activation. The specificity of CAR mediated T cell recognition is defined by the antibody domain, is independent of MHC presentation and can be extended to any target for which an antibody is available. We discuss the advantages and limitations of MHC-independent T cell targeting by an engineered CAR and review most significant progress recently made in early stage clinical trials to treat cancer.

Driving CAR T-cells forward

Science.gov (United States)

Jackson, Hollie J.; Rafiq, Sarwish; Brentjens, Renier J.

2017-01-01

The engineered expression of chimeric antigen receptors (CARs) on the surface of T cells enables the redirection of T-cell specificity. Early clinical trials using CAR T cells for the treatment of patients with cancer showed modest results, but the impressive outcomes of several trials of CD19-targeted CAR T cells in the treatment of patients with B-cell malignancies have generated an increased enthusiasm for this approach. Important lessons have been derived from clinical trials of CD19-specific CAR T cells, and ongoing clinical trials are testing CAR designs directed at novel targets involved in haematological and solid malignancies. In this Review, we discuss these trials and present strategies that can increase the antitumour efficacy and safety of CAR T-cell therapy. Given the fast-moving nature of this field, we only discuss studies with direct translational application currently or soon-to-be tested in the clinical setting. PMID:27000958

Live-cell imaging of invasion and intravasation in an artificial microvessel platform.

Science.gov (United States)

Wong, Andrew D; Searson, Peter C

2014-09-01

Methods to visualize metastasis exist, but additional tools to better define the biologic and physical processes underlying invasion and intravasation are still needed. One difficulty in studying metastasis stems from the complexity of the interface between the tumor microenvironment and the vascular system. Here, we report the development of an investigational platform that positions tumor cells next to an artificial vessel embedded in an extracellular matrix. On this platform, we used live-cell fluorescence microscopy to analyze the complex interplay between metastatic cancer cells and a functional artificial microvessel that was lined with endothelial cells. The platform recapitulated known interactions, and its use demonstrated the capabilities for a systematic study of novel physical and biologic parameters involved in invasion and intravasation. In summary, our work offers an important new tool to advance knowledge about metastasis and candidate antimetastatic therapies. ©2014 American Association for Cancer Research.

Use of internal control T-cell populations in the flow cytometric evaluation for T-cell neoplasms.

Science.gov (United States)

Hunt, Alicia M; Shallenberger, Wendy; Ten Eyck, Stephen P; Craig, Fiona E

2016-09-01

Flow cytometry is an important tool for identification of neoplastic T-cells, but immunophenotypic abnormalities are often subtle and must be distinguished from nonneoplastic subsets. Use of internal control (IC) T-cells in the evaluation for T-cell neoplasms was explored, both as a quality measure and as a reference for evaluating abnormal antigen expression. All peripheral blood specimens (3-month period), or those containing abnormal T-cells (29-month period), stained with CD45 V500, CD2 V450, CD3 PE-Cy7, CD7 PE, CD4 Per-CP-Cy5.5, CD8 APC-H7, CD56 APC, CD16&57 FITC, were evaluated. IC T-cells were identified (DIVA, BD Biosciences) and median fluorescence intensity (MFI) recorded. Selected files were merged and reference templates generated (Infinicyt, Cytognos). IC T-cells were present in all specimens, including those with abnormal T-cells, but subsets were less well-represented. IC T-cell CD3 MFI differed between instruments (p = 0.0007) and subsets (p < 0.001), but not specimen categories, and served as a longitudinal process control. Merged files highlighted small unusual IC-T subsets: CD2+(dim) (0.25% total), CD2- (0.03% total). An IC reference template highlighted neoplastic T-cells, but was limited by staining variability (IC CD3 MFI reference samples different from test (p = 0.003)). IC T-cells present in the majority of specimens can serve as positive and longitudinal process controls. Use of IC T-cells as an internal reference is limited by variable representation of subsets. Analysis of merged IC T-cells from previously analyzed patient samples can alert the interpreter to less-well-recognized non-neoplastic subsets. However, application of a merged file IC reference template was limited by staining variability. © 2016 Clinical Cytometry Society. © 2016 International Clinical Cytometry Society.

Peripheral T-Cell Lymphoma

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... Non-Hodgkin Lymphoma Peripheral T-Cell Lymphoma Primary Central Nervous System Lymphoma T-Cell Lymphoma Transformed Mycosis Fungoides Waldenstrom Macroglobulinemia Young Adult Lymphoma Overview Treatment Options Relapsed/Refractory Long-term ...

Angioimmunoblastic T-Cell Lymphoma

Science.gov (United States)

... Non-Hodgkin Lymphoma Peripheral T-Cell Lymphoma Primary Central Nervous System Lymphoma T-Cell Lymphoma Transformed Mycosis Fungoides Waldenstrom Macroglobulinemia Young Adult Lymphoma Overview Treatment Options Relapsed/Refractory Long-term ...

ADAMTS9-Regulated Pericellular Matrix Dynamics Governs Focal Adhesion-Dependent Smooth Muscle Differentiation

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Timothy J. Mead

2018-04-01

Full Text Available Summary: Focal adhesions anchor cells to extracellular matrix (ECM and direct assembly of a pre-stressed actin cytoskeleton. They act as a cellular sensor and regulator, linking ECM to the nucleus. Here, we identify proteolytic turnover of the anti-adhesive proteoglycan versican as a requirement for maintenance of smooth muscle cell (SMC focal adhesions. Using conditional deletion in mice, we show that ADAMTS9, a secreted metalloprotease, is required for myometrial activation during late gestation and for parturition. Through knockdown of ADAMTS9 in uterine SMC, and manipulation of pericellular versican via knockdown or proteolysis, we demonstrate that regulated pericellular matrix dynamics is essential for focal adhesion maintenance. By influencing focal adhesion formation, pericellular versican acts upstream of cytoskeletal assembly and SMC differentiation. Thus, pericellular versican proteolysis by ADAMTS9 balances pro- and anti-adhesive forces to maintain an SMC phenotype, providing a concrete example of the dynamic reciprocity of cells and their ECM. : Mead et al. identify a proteolytic mechanism that actively maintains a pericellular microenvironment conducive to uterine smooth muscle activation prior to parturition. They show that pericellular matrix proteolysis by the secreted metalloprotease ADAMTS9 is crucial for maintenance of focal adhesions in uterine smooth muscle cells, and its absence impairs parturition. Keywords: metalloprotease, extracellular matrix, smooth muscle, proteoglycan, myometrium, parturition, uterus, focal adhesion, proteolysis, interference reflection microscopy

Metabolic Adaptation of Human CD4+ and CD8+ T-Cells to T-Cell Receptor-Mediated Stimulation

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Nicholas Jones

2017-11-01

Full Text Available Linking immunometabolic adaptation to T-cell function provides insight for the development of new therapeutic approaches in multiple disease settings. T-cell activation and downstream effector functions of CD4+ and CD8+ T-cells are controlled by the strength of interaction between the T-cell receptor (TCR and peptides presented by human leukocyte antigens (pHLA. The role of TCR–pHLA interactions in modulating T-cell metabolism is unknown. Here, for the first time, we explore the relative contributions of the main metabolic pathways to functional responses in human CD4+ and CD8+ T-cells. Increased expression of hexokinase II accompanied by higher basal glycolysis is demonstrated in CD4+ T-cells; cytokine production in CD8+ T-cells is more reliant on oxidative phosphorylation. Using antigen-specific CD4+ and CD8+ T-cell clones and altered peptide ligands, we demonstrate that binding affinity tunes the underlying metabolic shift. Overall, this study provides important new insight into how metabolic pathways are controlled during antigen-specific activation of human T-cells.

Leukemia-Initiating Cells in T-Cell Acute Lymphoblastic Leukemia

OpenAIRE

Tan, Shi Hao; Bertulfo, Fatima Carla; Sanda, Takaomi

2017-01-01

T-cell acute lymphoblastic leukemia (T-ALL) is a hematological malignancy characterized by the clonal proliferation of immature T-cell precursors. T-ALL has many similar pathophysiological features to acute myeloid leukemia, which has been extensively studied in the establishment of the cancer stem cell (CSC) theory, but the CSC concept in T-ALL is still debatable. Although leukemia-initiating cells (LICs), which can generate leukemia in a xenograft setting, have been found in both human T-AL...

Murine neonatal spleen contains natural T and non-T suppressor cells capable of inhibiting adult alloreactive and newborn autoreactive T-cell proliferation.

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Hooper, D C; Hoskin, D W; Gronvik, K O; Murgita, R A

1986-05-01

The spleen of neonatal mice is known to be a rich source of cells capable of suppressing a variety of immune functions of adult lymphocytes in vitro. From such observations has emerged the concept that the gradual development in ability to express immune functions after birth is due in part to the parallel normal physiological decay of naturally occurring regulatory suppressor cells. There is, however, some confusion in the literature as to the exact nature of the newborn of the newborn inhibitory cell type(s). In contrast to most previous reports which detect only a single type of neonatal suppressor cell, usually a T cell, we show here that newborn spleen harbors both T and non-T inhibitory cells. Both types of suppressor cells could be shown to suppress the proliferative response of adult spleen to alloantigens as well as newborn T cells reacting against self-Ia antigen in the autologous mixed lymphocyte reaction (AMLR). Newborn suppressor T cells were characterized as being non-adherent to Ig-anti-Ig affinity columns, soybean agglutinin receptor negative (SBA-), and susceptible to lysis by anti-T-cell specific antiserum plus complement. Non-T suppressor cells were identified as non-phagocytic, SBA receptor positive (SBA+), and resistant to cytotoxic treatment with anti-T-cell antibodies and complement. The apparent controversy surrounding previous reports as to the T versus non-T nature of newborn suppressor cells can be reconciled by the present observation that both types of inhibitory cells coexist in the spleen. Furthermore, the demonstration that newborn suppressor cells can effectively regulate T-cell proliferative activity mediated by other newborn cells provides more direct support for the contention that such inhibitory cells play a physiological role in controlling immune responsiveness during early ontogeny.

Loss of ADAM9 expression impairs β1 integrin endocytosis, focal adhesion formation and cancer cell migration

DEFF Research Database (Denmark)

Mygind, Kasper J; Schwarz, Jeanette; Sahgal, Pranshu

2018-01-01

knockdown increases β1 integrin levels through mechanisms that are independent of its protease activity. In ADAM9-silenced cells, adhesion to collagen and fibronectin is reduced, suggesting an altered function of the accumulated integrins. Mechanistically, ADAM9 co-immunoprecipitates with β1 integrin......, and both internalization and subsequent degradation of β1 integrin are significantly decreased in ADAM9-silenced cells, with no effect on β1 integrin recycling. Accordingly, the formation of focal adhesions and actin stress fibres in ADAM9-silenced cells is altered, possibly explaining the reduction...

Accumulation of cytolytic CD8{sup +} T cells in B16-melanoma and proliferation of mature T cells in TIS21-knockout mice after T cell receptor stimulation

Energy Technology Data Exchange (ETDEWEB)

Ryu, Min Sook [Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, 164, World cul-ro, Yeongtong-gu, Suwon, Gyeonggi-do 443-380 (Korea, Republic of); Woo, Min-Yeong [Department of Microbiology, Ajou University School of Medicine, 164, World cul-ro, Yeongtong-gu, Suwon, Gyeonggi-do 443-380 (Korea, Republic of); Department of Biomedical Sciences, The Graduate School, Ajou University (Korea, Republic of); Kwon, Daeho [Department of Microbiology, Kwandong University College of Medicine, Gangneung, Gangwon-do 210-701 (Korea, Republic of); Hong, Allen E. [Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, 164, World cul-ro, Yeongtong-gu, Suwon, Gyeonggi-do 443-380 (Korea, Republic of); Song, Kye Yong [Department of Pathology, Chung-Ang University College of Medicine, Dongjak-gu, Seoul 156-756 (Korea, Republic of); Park, Sun [Department of Microbiology, Ajou University School of Medicine, 164, World cul-ro, Yeongtong-gu, Suwon, Gyeonggi-do 443-380 (Korea, Republic of); Lim, In Kyoung [Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, 164, World cul-ro, Yeongtong-gu, Suwon, Gyeonggi-do 443-380 (Korea, Republic of)

2014-10-01

In vivo and in vitro effects of TIS21 gene on the mature T cell activation and antitumor activities were explored by employing MO5 melanoma orthograft and splenocytes isolated from the TIS21-knockout (KO) mice. Proliferation and survival of mature T cells were significantly increased in the KO than the wild type (WT) cells, indicating that TIS21 inhibits the rate of mature T cell proliferation and its survival. In MO5 melanoma orthograft model, the KO mice recruited much more CD8{sup +} T cells into the tumors at around day 14 after tumor cell injection along with reduced tumor volumes compared with the WT. The increased frequency of granzyme B{sup +} CD8{sup +} T cells in splenocytes of the KO mice compared with the WT may account for antitumor-immunity of TIS21 gene in the melanoma orthograft. In contrast, reduced frequencies of CD107a{sup +} CD8{sup +} T cells in the splenocytes of KO mice may affect the loss of CD8{sup +} T cell infiltration in the orthograft at around day 19. These results indicate that TIS21 exhibits antiproliferative and proapoptotic effects in mature T cells, and differentially affects the frequencies of granzyme B{sup +} CD8{sup +} T-cells and CD107a{sup +} CD8{sup +} T-cells, thus transiently regulating in vivo anti-tumor immunity. - Highlights: • Constitutive expression of TIS21 in splenocytes and upregulation by TCR stimulation. • Proliferation of mature T-cells in spleen of TIS21KO mice after TCR stimulation. • Inhibition of cell death in mature T-cells of TIS21KO mice compared with the wild type. • Inhibition of melanoma growth in TIS21KO mice and CD8{sup +} T cell infiltration in tumor. • Reduction of CD 107{sup +}CD8{sup +} T cells, but increased granzyme B{sup +} CD8{sup +} T cells in TIS21KO mice.

Conventional CD4+ T cells present bacterial antigens to induce cytotoxic and memory CD8+ T cell responses.

Science.gov (United States)

Cruz-Adalia, Aránzazu; Ramirez-Santiago, Guillermo; Osuna-Pérez, Jesús; Torres-Torresano, Mónica; Zorita, Virgina; Martínez-Riaño, Ana; Boccasavia, Viola; Borroto, Aldo; Martínez Del Hoyo, Gloria; González-Granado, José María; Alarcón, Balbino; Sánchez-Madrid, Francisco; Veiga, Esteban

2017-11-17

Bacterial phagocytosis and antigen cross-presentation to activate CD8 + T cells are principal functions of professional antigen presenting cells. However, conventional CD4 + T cells also capture and kill bacteria from infected dendritic cells in a process termed transphagocytosis (also known as transinfection). Here, we show that transphagocytic T cells present bacterial antigens to naive CD8 + T cells, which proliferate and become cytotoxic in response. CD4 + T-cell-mediated antigen presentation also occurs in vivo in the course of infection, and induces the generation of central memory CD8 + T cells with low PD-1 expression. Moreover, transphagocytic CD4 + T cells induce protective anti-tumour immune responses by priming CD8 + T cells, highlighting the potential of CD4 + T cells as a tool for cancer immunotherapy.

CD 4 + CD 25 + T cells maintain homeostasis by promoting TER - 119 cell development and inhibiting T cell activation

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Muhaimin Rifa’i

2014-05-01

Full Text Available CD4+ CD25+ regulatory T cells involved in the regulation of self- tolerance and normality of homeostasis. CD122 deficient mice are model animals that have an abnormal immune system characteristically have a high number of activated T cells and TER-119 cell decreased. Here we showed evidence that the transfer of CD4+ CD25+ regulatory T cells derived from normal mice to CD122- defficient neonates prevent the development of activated memory T cells and elicit TER-119 differentiation. Bone marrow reconstitution derived from CD122-/- mice to normal mice resulting tolerance to individual that genetically different. Importantly, CD4+ CD25+ regulatory T cells derived from normal mice can replace CD4+ CD25+ cells derived from CD122-/- mice. The results of this experiment suggest that regulatory T cells from normal mice exert a critical role in maintaining peripheral tolerance and controlling hematopoietic disorder.

T cells in vascular inflammatory diseases

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Lucas L Lintermans

2014-10-01

Full Text Available Inflammation of the human vasculature is a manifestation of many different diseases ranging from systemic autoimmune diseases to chronic inflammatory diseases, in which multiple types of immune cells are involved. For both autoimmune diseases and chronic inflammatory diseases several observations support a key role for T lymphocytes in these disease pathologies, but the underlying mechanisms are poorly understood. Previous studies in several autoimmune diseases have demonstrated a significant role for a specific subset of CD4+ T cells termed effector memory T cells. This expanded population of effector memory T cells may contribute to tissue injury and disease progression. These cells exert multiple pro-inflammatory functions through the release of effector cytokines. Many of these cytokines have been detected in the inflammatory lesions and participate in the vasculitic reaction, contributing to recruitment of macrophages, neutrophils, dendritic cells, NK cells, B cells and T cells. In addition, functional impairment of regulatory T cells paralyzes anti-inflammatory effects in vasculitic disorders. Interestingly, activation of effector memory T cells in uniquely dependent on the voltage-gated Kv1.3 potassium channel providing an anchor for specific drug targeting. In this review, we focus on the CD4+ T cells in the context of vascular inflammation and describe the evidence supporting the role of different T cell subsets in vascular inflammation. Selective targeting of pathogenic effector memory T cells might enable a more tailored therapeutic approach that avoids unwanted adverse side effects of generalized immunosuppression by modulating the effector functions of T cell responses to inhibit the development of vascular inflammation.

Dynamics of human T-cell lymphotropic virus I (HTLV-I) infection of CD4+ T-cells.

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Katri, Patricia; Ruan, Shigui

2004-11-01

Stilianakis and Seydel (Bull. Math. Biol., 1999) proposed an ODE model that describes the T-cell dynamics of human T-cell lymphotropic virus I (HTLV-I) infection and the development of adult T-cell leukemia (ATL). Their model consists of four components: uninfected healthy CD4+ T-cells, latently infected CD4+ T-cells, actively infected CD4+ T-cells, and ATL cells. Mathematical analysis that completely determines the global dynamics of this model has been done by Wang et al. (Math. Biosci., 2002). In this note, we first modify the parameters of the model to distinguish between contact and infectivity rates. Then we introduce a discrete time delay to the model to describe the time between emission of contagious particles by active CD4+ T-cells and infection of pure cells. Using the results in Culshaw and Ruan (Math. Biosci., 2000) in the analysis of time delay with respect to cell-free viral spread of HIV, we study the effect of time delay on the stability of the endemically infected equilibrium. Numerical simulations are presented to illustrate the results.

First step in developing a 3D biodegradable fibrin scaffold for an artificial ovary.

Science.gov (United States)

Luyckx, Valérie; Dolmans, Marie-Madeleine; Vanacker, Julie; Scalercio, Sarah R; Donnez, Jacques; Amorim, Christiani A

2013-11-25

Although transplantation of cryopreserved ovarian tissue is a promising approach to restore fertility in cancer patients, it is not advisable for women at risk of ovarian involvement due to the threat of reintroducing malignant cells. The aim of this study was therefore to find an alternative for these patients by development of an artificial ovary. For construction of the artificial ovary matrix, we used a central composite design to investigate nine combinations of fibrinogen (mg/ml) and thrombin (IU/mL) (F/T): F1/T4, F12.5/T1, F12.5/T20, F25/T0.1, F25/T4, F25/T500, F50/T1, F50/T20 and F100/T4. From the first qualitative analyses (handling and matrix size), five combinations (F12.5/T1, F25/T4, F50/T20, F50/T1 and F100/T4) yielded positive results. They were further evaluated in order to assess fibrin matrix degradation and homogeneous cell encapsulation (density), survival and proliferation (Ki67), and atresia (TUNEL) before and after 7 days of in vitro culture. To determine the best compromise between maximizing the dynamic density (Y1) and minimizing the apoptosis rate (Y2), we used the desirability function approach. Two combinations (F12.5/T1 and F25/T4) showed greater distribution of cells before in vitro culture, reproducible degradation of the fibrin network and adequate support for isolated human ovarian stromal cells, with a high proportion of Ki67-positive cells. SEM analysis revealed a network of fibers with regular pores and healthy stromal cells after in vitro culture with both F/T combinations. This study reports two optimal F/T combinations that allow survival and proliferation of isolated human ovarian cells. Further studies are required to determine if such a scaffold will also be a suitable environment for isolated ovarian follicles.

Antigen-specific T8+ human clone of cells with a nonspecific augmenting function on the T4 cell-B cell helper interaction

International Nuclear Information System (INIS)

Brines, R.D.; Sia, D.Y.; Lehner, T.

1987-01-01

The authors isolated a T8 + T3 + Ia + clone of cells from the peripheral blood mononuclear cells of a healthy subject. The clone was expanded and maintained with autologous feed cells, interleukin 2, and a streptococcal antigen. The T8 + clone of cells responded specifically to the streptococcal antigen, in the absence of accessory cells,and released a soluble factor. Both the cloned cells and the corresponding soluble factor expressed augmenting helper but not suppressor activity. The augmenting helper activity for B cell antibody synthesis was demonstrable only in the presence of autologous T 4 cells. Radioimmunoassay was used to measure antibodies. Although stimulation of the T8 + cloned cells was antigen-specific, the resulting soluble factor elicited nonspecific antibody synthesis in the presence of T4 and B cells. The T8 + cloned cell-derived factor was adsorbed by B cells but not by T4 cells. Preliminary studies suggest that the factor has the properties of a B cell growth factor. They suggest that the T8 + population consists of functionally heterogeneous cell subsets, some that have suppressor function and others that augment the T4 + helper-inducer activity in B cell antibody synthesis

Generation of T cell effectors using tumor cell-loaded dendritic cells for adoptive T cell therapy

Czech Academy of Sciences Publication Activity Database

Vávrová, K.; Vrabcova, P.; Filipp, Dominik; Bartunkova, J.; Horváth, R.

2016-01-01

Roč. 33, č. 12 (2016), č. článku 136. ISSN 1357-0560 R&D Projects: GA ČR(CZ) GBP302/12/G101 Institutional support: RVO:68378050 Keywords : Cancer Immunotherapy * Prostate cancer * Adoptive T cell therapy * Tumor-specific T cell expansion Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.634, year: 2016

Contribution of herpesvirus specific CD8 T cells to anti-viral T cell response in humans.

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Elena Sandalova

Full Text Available Herpesviruses infect most humans. Their infections can be associated with pathological conditions and significant changes in T cell repertoire but evidences of symbiotic effects of herpesvirus latency have never been demonstrated. We tested the hypothesis that HCMV and EBV-specific CD8 T cells contribute to the heterologous anti-viral immune response. Volume of activated/proliferating virus-specific and total CD8 T cells was evaluated in 50 patients with acute viral infections: 20 with HBV, 12 with Dengue, 12 with Influenza, 3 with Adenovirus infection and 3 with fevers of unknown etiology. Virus-specific (EBV, HCMV, Influenza pentamer+ and total CD8 T cells were analyzed for activation (CD38/HLA-DR, proliferation (Ki-67/Bcl-2(low and cytokine production. We observed that all acute viral infections trigger an expansion of activated/proliferating CD8 T cells, which differs in size depending on the infection but is invariably inflated by CD8 T cells specific for persistent herpesviruses (HCMV/EBV. CD8 T cells specific for other non-related non persistent viral infection (i.e. Influenza were not activated. IL-15, which is produced during acute viral infections, is the likely contributing mechanism driving the selective activation of herpesvirus specific CD8 T cells. In addition we were able to show that herpesvirus specific CD8 T cells displayed an increased ability to produce the anti-viral cytokine interferon-gamma during the acute phase of heterologous viral infection. Taken together, these data demonstrated that activated herpesvirus specific CD8 T cells inflate the activated/proliferating CD8 T cells population present during acute viral infections in human and can contribute to the heterologous anti-viral T cell response.

Circumvention of regulatory CD4(+) T cell activity during cross-priming strongly enhances T cell-mediated immunity.

Science.gov (United States)

Heit, Antje; Gebhardt, Friedemann; Lahl, Katharina; Neuenhahn, Michael; Schmitz, Frank; Anderl, Florian; Wagner, Hermann; Sparwasser, Tim; Busch, Dirk H; Kastenmüller, Kathrin

2008-06-01

Immunization with purified antigens is a safe and practical vaccination strategy but is generally unable to induce sustained CD8(+) T cell-mediated protection against intracellular pathogens. Most efforts to improve the CD8(+) T cell immunogenicity of these vaccines have focused on co-administration of adjuvant to support cross-presentation and dendritic cell maturation. In addition, it has been shown that CD4(+) T cell help during the priming phase contributes to the generation of protective CD8(+) memory T cells. In this report we demonstrate that the depletion of CD4(+) T cells paradoxically enhances long-lasting CD8-mediated protective immunity upon protein vaccination. Functional and genetic in vivo inactivation experiments attribute this enhancement primarily to MHC class II-restricted CD4(+) regulatory T cells (Treg), which appear to physiologically suppress the differentiation process towards long-living effector memory T cells. Since, in functional terms, this suppression by Treg largely exceeds the positive effects of conventional CD4(+) T cell help, even the absence of all CD4(+) T cells or lack of MHC class II-mediated interactions on priming dendritic cells result in enhanced CD8(+) T cell immunogenicity. These findings have important implications for the improvement of vaccines against intracellular pathogens or tumors, especially in patients with highly active Treg.

Vitamin D controls T cell antigen receptor signaling and activation of human T cells

DEFF Research Database (Denmark)

von Essen, Marina Rode; Kongsbak-Wismann, Martin; Schjerling, Peter

2010-01-01

Phospholipase C (PLC) isozymes are key signaling proteins downstream of many extracellular stimuli. Here we show that naive human T cells had very low expression of PLC-gamma1 and that this correlated with low T cell antigen receptor (TCR) responsiveness in naive T cells. However, TCR triggering...... led to an upregulation of approximately 75-fold in PLC-gamma1 expression, which correlated with greater TCR responsiveness. Induction of PLC-gamma1 was dependent on vitamin D and expression of the vitamin D receptor (VDR). Naive T cells did not express VDR, but VDR expression was induced by TCR...... signaling via the alternative mitogen-activated protein kinase p38 pathway. Thus, initial TCR signaling via p38 leads to successive induction of VDR and PLC-gamma1, which are required for subsequent classical TCR signaling and T cell activation....

Normal variation of focal T2 Hyperintensities in anterior parietal periventricular white matter: Another 'Terminal Zones of Myelination'

International Nuclear Information System (INIS)

Park, Jong Oag; Woo, Je Ho; Ki, Tae Sung; Lee, Jong Hwa; Chung, Jin Woo; Lee, Don Young

1994-01-01

It has been known that there are several areas of T2 hyperintensity in normal white matter of brain, such as terminal zones of myelination, ependymitis granularis, ones of posterior internal capsule, and perivascular space. The aim of our study is to demonstrate another region of T2 hyperintensities in normal pediatric age group. We have studied brain MR for 10 normal volunteers and 35 patients without having intracranial lesions in pediatric age group(3-19 years). In 5 among 45 cases, focal T2 hyperintensities were seen in the parietal periventricular white matter beneath the postcentral gyri. They were noted as poorly defined, 5-10 mm sized areas of increased signal intensities on T2-weighted axial images. They were also characterized by bilateral, posteromedially oriented, short band-like or oval areas. Interestingly, they were directly continuous with the T2 hyperintensity of posterior internal capsule. In spite of the relatively highly frequency in the pediatric population as in our study, this finding has not been reported in the asymptomatic adults. The results show that the bilateral anterior parietal hyperintense areas may be another terminal zones of delayed myelination affecting the parietopontine tract. They should be differentiated from pathologic T2 hyperintensities by their characteristic findings

PD-L1-specific T cells

DEFF Research Database (Denmark)

Ahmad, Shamaila Munir; Borch, Troels Holz; Hansen, Morten

2016-01-01

-specific T cells that recognize both PD-L1-expressing immune cells and malignant cells. Thus, PD-L1-specific T cells have the ability to modulate adaptive immune reactions by reacting to regulatory cells. Thus, utilization of PD-L1-derived T cell epitopes may represent an attractive vaccination strategy...... for targeting the tumor microenvironment and for boosting the clinical effects of additional anticancer immunotherapy. This review summarizes present information about PD-L1 as a T cell antigen, depicts the initial findings about the function of PD-L1-specific T cells in the adjustment of immune responses...

FAK/src-family dependent activation of the Ste20-like kinase SLK is required for microtubule-dependent focal adhesion turnover and cell migration.

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Simona Wagner

2008-04-01

Full Text Available Cell migration involves a multitude of signals that converge on cytoskeletal reorganization, essential for development, immune responses and tissue repair. Using knockdown and dominant negative approaches, we show that the microtubule-associated Ste20-like kinase SLK is required for focal adhesion turnover and cell migration downstream of the FAK/c-src complex. Our results show that SLK co-localizes with paxillin, Rac1 and the microtubules at the leading edge of migrating cells and is activated by scratch wounding. SLK activation is dependent on FAK/c-src/MAPK signaling, whereas SLK recruitment to the leading edge is src-dependent but FAK independent. Our results show that SLK represents a novel focal adhesion disassembly signal.

Ultrathin Alvarez lens system actuated by artificial muscles.

Science.gov (United States)

Petsch, S; Grewe, A; Köbele, L; Sinzinger, S; Zappe, H

2016-04-01

A key feature of Alvarez lenses is that they may be tuned in focal length using lateral rather than axial translation, thus reducing the overall length of a focus-tunable optical system. Nevertheless the bulk of classical microsystems actuators limits further miniaturization. We present here a new, ultrathin focus-tunable Alvarez lens fabricated using molding techniques and actuated using liquid crystal elastomer (LCE) artificial muscle actuators. The large deformation generated by the LCE actuators permits the integration of the actuators in-plane with the mechanical and optical system and thus reduces the device thickness to only 1.6 mm. Movement of the Alvarez lens pair of 178 μm results in a focal length change of 3.3 mm, based on an initial focal length of 28.4 mm. This design is of considerable interest for realization of ultraflat focus-tunable and zoom systems.

T Cell Subset and Stimulation Strength-Dependent Modulation of T Cell Activation by Kv1.3 Blockers.

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Wai-Ping Fung-Leung

Full Text Available Kv1.3 is a voltage-gated potassium channel expressed on T cells that plays an important role in T cell activation. Previous studies have shown that blocking Kv1.3 channels in human T cells during activation results in reduced calcium entry, cytokine production, and proliferation. The aim of the present study was to further explore the effects of Kv1.3 blockers on the response of different human T cell subsets under various stimulation conditions. Our studies show that, unlike the immune suppressor cyclosporine A, the inhibitory effect of Kv1.3 blockers was partial and stimulation strength dependent, with reduced inhibitory efficacy on T cells under strengthened anti-CD3/CD28 stimulations. T cell responses to allergens including house dust mites and ragweed were partially reduced by Kv1.3 blockers. The effect of Kv1.3 inhibition was dependent on T cell subsets, with stronger effects on CCR7- effector memory compared to CCR7+ central memory CD4 T cells. Calcium entry studies also revealed a population of CD4 T cells resistant to Kv1.3 blockade. Activation of CD4 T cells was accompanied with an increase in Kv1.3 currents but Kv1.3 transcripts were found to be reduced, suggesting a posttranscriptional mechanism in the regulation of Kv1.3 activities. In summary, Kv1.3 blockers inhibit T cell activation in a manner that is highly dependent on the T cell identity and stimulation strength, These findings suggest that Kv1.3 blockers inhibit T cells in a unique, conditional manner, further refining our understanding of the therapeutic potential of Kv1.3 blockers.

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

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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.

Serial neuroradiological studies in focal cerebritis

International Nuclear Information System (INIS)

Hatta, S.; Mochizuki, H.; Kuru, Y.; Miwa, H.; Kondo, T.; Mori, H.; Mizuno, Y.

1994-01-01

We report serial neuroradiological studies in a patient with focal cerebritis in the head of the left caudate nucleus. On the day after the onset of symptoms, CT showed an ill-defined low density lesion. The lack of contrast enhancement appeared to be the most important finding for differentiating focal cerebritis from an encapsulated brain abscess or a tumour. MRI two days later revealed the centre of the lesion to be of slightly low intensity on T1-weighted inversion recovery (IR) images and very low intensity on T2-weighted spin echo images, which appeared to correspond to the early cerebritis stage of experimentally induced cerebritis and brain abscess. Ten days after the onset of symptoms, CT revealed a thin ring of enhancement in the head of the caudate nucleus, and a similar small ring was seen in the hypothalamus 16 days after the onset, corresponding to the late cerebritis stage. MRI nine days later revealed ill-defined high signal lesions within the involved area on the T1-weighted IR images. To our knowledge, this is the first published MRI documentation of the early cerebritis stage developing into an encapsulated brain abscess. The mechanisms underlying of these radiographic changes are discussed. (orig.)

Concentric artificial impedance surface for directional sound beamforming

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Kyungjun Song

2017-03-01

Full Text Available Utilizing acoustic metasurfaces consisting of subwavelength resonant textures, we design an artificial impedance surface by creating a new boundary condition. We demonstrate a circular artificial impedance surface with surface impedance modulation for directional sound beamforming in three-dimensional space. This artificial impedance surface is implemented by revolving two-dimensional Helmholtz resonators with varying internal coiled path. Physically, the textured surface has inductive surface impedance on its inner circular patterns and capacitive surface impedance on its outer circular patterns. Directional receive beamforming can be achieved using an omnidirectional microphone located at the focal point formed by the gradient-impeding surface. In addition, the uniaxial surface impedance patterning inside the circular aperture can be used for steering the direction of the main lobe of the radiation pattern.

Toward a new generation of therapeutics: artificial cell targeted delivery of live cells for therapy.

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Prakash, Satya; Martoni, Christopher

2006-01-01

Scientific evidence in the prevention and treatment of various disorders is accumulating regarding probiotics. The health benefits supported by adequate clinical data include increased resistance to infectious disease, decreased duration of diarrhea, management of inflammatory bowel disease, reduction of serum cholesterol, prevention of allergy, modulation of cytokine gene expression, and suppression of carcinogen production. Recent ventures in metabolic engineering and heterologous protein expression have enhanced the enzymatic and immunomodulatory effects of probiotics and, with time, may allow more active intervention among critical care patients. In addition, a number of approaches are currently being explored, including the physical and chemical protection of cells, to increase probiotic viability and its health benefits. Traditional immobilization of probiotics in gel matrices, most notably calcium alginate and kappa-carrageenan, has frequently been employed, with noted improvements in viability during freezing and storage. Conflicting reports exist, however, on the protection offered by immobilization from harsh physiologic environments. An alternative approach, microencapsulation in "artificial cells," builds on immobilization technologies by combining enhanced mechanical stability of the capsule membrane with improved mass transport, increased cell loading, and greater control of parameters. This review summarizes the current clinical status of probiotics, examines the promises and challenges of current immobilization technologies, and presents the concept of artificial cells for effective delivery of therapeutic bacterial cells.

Regulatory T cells and B cells: implication on autoimmune diseases

OpenAIRE

Wang, Ping; Zheng, Song Guo

2013-01-01

The regulatory T (Treg) cells play an important role in the maintenance of homeostasis and the prevention of autoimmune diseases. Although most studies are focusing on the role of Treg cells in T cells and T cells-mediated diseases, these cells also directly affect B cells and other non-T cells. This manuscript updates the role of Treg cells on the B cells and B cell-mediated diseases. In addition, the mechanisms whereby Treg cells suppress B cell responses have been discussed.

Artificial neural network-aided image analysis system for cell counting.

Science.gov (United States)

Sjöström, P J; Frydel, B R; Wahlberg, L U

1999-05-01

In histological preparations containing debris and synthetic materials, it is difficult to automate cell counting using standard image analysis tools, i.e., systems that rely on boundary contours, histogram thresholding, etc. In an attempt to mimic manual cell recognition, an automated cell counter was constructed using a combination of artificial intelligence and standard image analysis methods. Artificial neural network (ANN) methods were applied on digitized microscopy fields without pre-ANN feature extraction. A three-layer feed-forward network with extensive weight sharing in the first hidden layer was employed and trained on 1,830 examples using the error back-propagation algorithm on a Power Macintosh 7300/180 desktop computer. The optimal number of hidden neurons was determined and the trained system was validated by comparison with blinded human counts. System performance at 50x and lO0x magnification was evaluated. The correlation index at 100x magnification neared person-to-person variability, while 50x magnification was not useful. The system was approximately six times faster than an experienced human. ANN-based automated cell counting in noisy histological preparations is feasible. Consistent histology and computer power are crucial for system performance. The system provides several benefits, such as speed of analysis and consistency, and frees up personnel for other tasks.

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.

TCR tuning of T cell subsets.

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Cho, Jae-Ho; Sprent, Jonathan

2018-05-01

After selection in the thymus, the post-thymic T cell compartments comprise heterogenous subsets of naive and memory T cells that make continuous T cell receptor (TCR) contact with self-ligands bound to major histocompatibility complex (MHC) molecules. T cell recognition of self-MHC ligands elicits covert TCR signaling and is particularly important for controlling survival of naive T cells. Such tonic TCR signaling is tightly controlled and maintains the cells in a quiescent state to avoid autoimmunity. Here, we review how naive and memory T cells are differentially tuned and wired for TCR sensitivity to self and foreign ligands. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Perspectives on Regulatory T Cell Therapies.

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Probst-Kepper, Michael; Kröger, Andrea; Garritsen, Henk S P; Buer, Jan

2009-01-01

Adoptive transfer in animal models clearly indicate an essential role of CD4+ CD25+ FOXP3+ regulatory T (T(reg)) cells in prevention and treatment of autoimmune and graft-versus-host disease. Thus, T(reg) cell therapies and development of drugs that specifically enhance T(reg) cell function and development represent promising tools to establish dominant tolerance. So far, lack of specific markers to differentiate human T(reg) cells from activated CD4+ CD25+ effector T cells, which also express FOXP3 at different levels, hampered such an approach. Recent identification of the orphan receptor glycoprotein-A repetitions predominant (GARP or LRRC32) as T(reg) cell-specific key molecule that dominantly controls FOXP3 via a positive feedback loop opens up new perspectives for molecular and cellular therapies. This brief review focuses on the role of GARP as a safeguard of a complex regulatory network of human T(reg) cells and its implications for regulatory T cell therapies in autoimmunity and graft-versus-host disease.

Comparing the mechanical influence of vinculin, focal adhesion kinase and p53 in mouse embryonic fibroblasts

International Nuclear Information System (INIS)

Klemm, Anna H.; Diez, Gerold; Alonso, Jose-Luis; Goldmann, Wolfgang H.

2009-01-01

Cytoskeletal reorganization is an ongoing process when cells adhere, move or invade extracellular substrates. The cellular force generation and transmission are determined by the intactness of the actomyosin-(focal adhesion complex)-integrin connection. We investigated the intracellular course of action in mouse embryonic fibroblasts deficient in the focal adhesion proteins vinculin and focal adhesion kinase (FAK) and the nuclear matrix protein p53 using magnetic tweezer and nanoparticle tracking techniques. Results show that the lack of these proteins decrease cellular stiffness and affect cell rheological behavior. The decrease in cellular binding strength was higher in FAK- to vinculin-deficient cells, whilst p53-deficient cells showed no effect compared to wildtype cells. The intracellular cytoskeletal activity was lowest in wildtype cells, but increased in the following order when cells lacked FAK+p53 > p53 > vinculin. In summary, cell mechanical processes are differently affected by the focal adhesion proteins vinculin and FAK than by the nuclear matrix protein, p53.

Evaluation of focal cartilage lesions of the knee using MRI T2 mapping and delayed Gadolinium Enhanced MRI of Cartilage (dGEMRIC).

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Årøen, Asbjørn; Brøgger, Helga; Røtterud, Jan Harald; Sivertsen, Einar Andreas; Engebretsen, Lars; Risberg, May Arna

2016-02-11

Assessment of degenerative changes of the cartilage is important in knee cartilage repair surgery. Magnetic Resonance Imaging (MRI) T2 mapping and delayed Gadolinium Enhanced MRI of Cartilage (dGEMRIC) are able to detect early degenerative changes. The hypothesis of the study was that cartilage surrounding a focal cartilage lesion in the knee does not possess degenerative changes. Twenty-eight consecutive patients included in a randomized controlled trial on cartilage repair were evaluated using MRI T2 mapping and dGEMRIC before cartilage treatment was initiated. Inclusion was based on disabling knee problems (Lysholm score of ≤ 75) due to an arthroscopically verified focal femoral condyle cartilage lesion. Furthermore, no major malalignments or knee ligament injuries were accepted. Mean patient age was 33 ± 9.6 years, and the mean duration of knee symptoms was 49 ± 60 months. The MRI T2 mapping and the dGEMRIC measurements were performed at three standardized regions of interest (ROIs) at the medial and lateral femoral condyle, avoiding the cartilage lesion The MRI T2 mapping of the cartilage did not demonstrate significant differences between condyles with or without cartilage lesions. The dGEMRIC results did not show significantly lower values of the affected condyle compared with the opposite condyle and the contra-lateral knee in any of the ROIs. The intraclass correlation coefficient (ICC) of the dGEMRIC readings was 0.882. The MRI T2 mapping and the dGEMRIC confirmed the arthroscopic findings that normal articular cartilage surrounded the cartilage lesion, reflecting normal variation in articular cartilage quality. NCT00885729 , registered April 17 2009.

Human retinal pigment epithelial cell-induced apoptosis in activated T cells

DEFF Research Database (Denmark)

Jørgensen, A; Wiencke, A K; la Cour, M

1998-01-01

human retinal pigment epithelial (RPE) cells can induce apoptosis in activated T cells. METHODS: Fas ligand (FasL) expression was detected by flow cytometry and immunohistochemistry. Cultured RPE cells were cocultured with T-cell lines and peripheral blood lymphocytes for 6 hours to 2 days. Induction...... of apoptosis was detected by 7-amino-actinomycin D and annexin V staining. RESULTS: Retinal pigment epithelial cells expressed FasL and induced apoptosis in activated Fas+ T cells. Blocking of Fas-FasL interaction with antibody strongly inhibited RPE-mediated T-cell apoptosis. Retinal pigment epithelial cells...... induced apoptosis in several activated T-cell populations and T-cell lines, including T-cell antigen receptor (TCR)-CD3-negative T-cell lines. In contrast, RPE cells induced little or no apoptosis in resting peripheral T cells. Major histocompatibility complex (MHC) class II monoclonal antibodies, which...

Expression of activating natural killer-cell receptors is a hallmark of the innate-like T-cell neoplasm in peripheral T-cell lymphomas.

Science.gov (United States)

Uemura, Yu; Isobe, Yasushi; Uchida, Akiko; Asano, Junko; Nishio, Yuji; Sakai, Hirotaka; Hoshikawa, Masahiro; Takagi, Masayuki; Nakamura, Naoya; Miura, Ikuo

2018-04-01

Peripheral T- or natural killer (NK)-cell lymphomas are rare and difficult-to-recognize diseases. It remains arduous to distinguish between NK cell- and cytotoxic T-lymphocyte-derived lymphomas through routine histological evaluation. To clarify the cells of origin, we focused on NK-cell receptors and examined the expression using immunohistochemistry in 22 cases with T- and NK-cell neoplasms comprising angioimmunoblastic T-cell lymphoma, anaplastic lymphoma kinase (ALK)-positive and -negative anaplastic large-cell lymphomas, extranodal NK/T-cell lymphoma, nasal type, monomorphic epitheliotropic intestinal T-cell lymphoma, aggressive NK-cell leukemia, and other peripheral T-cell lymphomas. Inhibitory receptor leukocyte immunoglobulin-like receptor subfamily B member 1 (LILRB1) was detected in 14 (64%) cases, whereas activating receptors DNAM1, NKp46, and NKG2D were expressed in 7 (32%), 9 (41%), and 5 (23%) cases, respectively. Although LILRB1 was detected regardless of the disease entity, the activating NK-cell receptors were expressed predominantly in TIA-1-positive neoplasms (DNAM1, 49%; NKp46, 69%; and NKG2D, 38%). In addition, NKp46 and NKG2D were detected only in NK-cell neoplasms and cytotoxic T-lymphocyte-derived lymphomas including monomorphic epitheliotropic intestinal T-cell lymphoma. One Epstein-Barr virus-harboring cytotoxic T-lymphocyte-derived lymphoma mimicking extranodal NK/T-cell lymphoma, nasal type lacked these NK-cell receptors, indicating different cell origin from NK and innate-like T cells. Furthermore, NKG2D expression showed a negative impact on survival among the 22 examined cases, which mainly received the standard chemotherapy regimen (log-rank test, P = .024). We propose that the presence of activating NK-cell receptors may provide new insights into understanding peripheral T-cell lymphomas and characterizing them as innate-like T-cell neoplasm. © 2018 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on

Clinical significance of T-cell clonality in mycosis fungoides and other cutaneous T-cell lymphomas

NARCIS (Netherlands)

Muche, Joachim Marcus

2010-01-01

The purpose of this thesis was to obtain more insight into T-cell clonality in blood of mycosis fungoides (MF) patients. Investigation of the frequency of blood T-cell clonality clearly indicated early dissemination of neoplastic T-cells into skin and blood as a sign of physiological recirculation.

Focal Amyloidosis of the Orbit Presenting as a Mass: MRI and CT Features

International Nuclear Information System (INIS)

Yerli, Hasan; Aydin, Erdinc; Avci, Suat; Haberal, Nihan; Oto, Sibel

2011-01-01

Focal orbital amyloidosis is a rare entity and little is known about its magnetic resonance imaging (MRI) features. In this case report, imaging features of a case of focal orbital amyloidosis presenting as a mass have been documented together with its histopathological findings. On MRI, a well-defined mass was seen as isointense with rectus muscle on T1-weighted images and heterogeneously hypointense on T2-weighted images. Punctuate calcifications were observed on the computerized tomography (CT) examination

T cell reconstitution in allogeneic haematopoietic stem cell transplantation

DEFF Research Database (Denmark)

Kielsen, K; Jordan, K K; Uhlving, H H

2015-01-01

Infections and acute graft-versus-host disease (aGVHD) are major causes of treatment-related mortality and morbidity following allogeneic haematopoietic stem cell transplantation (HSCT). Both complications depend on reconstitution of the T-lymphocyte population based on donor T cells. Although...... it is well established that Interleukin-7 (IL-7) is a cytokine essential for de novo T cell development in the thymus and homoeostatic peripheral expansion of T cells, associations between circulating levels of IL-7 and T cell reconstitution following HSCT have not been investigated previously. We...... in patients treated with anti-thymocyte globulin (ATG) compared with those not treated with ATG (P = 0.0079). IL-7 levels at day +7 were negatively associated with T cell counts at day +30 to +60 (at day +60: CD3(+) : β = -10.6 × 10(6) cells/l, P = 0.0030; CD8(+) : β = -8.4 × 10(6) cells/l, P = 0.061; CD4...

CD8+ T cells induce thyroid epithelial cell hyperplasia and fibrosis.

Science.gov (United States)

Yu, Shiguang; Fang, Yujiang; Sharav, Tumenjargal; Sharp, Gordon C; Braley-Mullen, Helen

2011-02-15

CD8(+) T cells can be important effector cells in autoimmune inflammation, generally because they can damage target cells by cytotoxicity. This study shows that activated CD8(+) T cells induce thyroid epithelial cell hyperplasia and proliferation and fibrosis in IFN-γ(-/-) NOD.H-2h4 SCID mice in the absence of CD4(+) T cells. Because CD8(+) T cells induce proliferation rather than cytotoxicity of target cells, these results describe a novel function for CD8(+) T cells in autoimmune disease. In contrast to the ability of purified CD8(+) T cells to induce thyrocyte proliferation, CD4(+) T cells or CD8 T cell-depleted splenocytes induced only mild thyroid lesions in SCID recipients. T cells in both spleens and thyroids highly produce TNF-α. TNF-α promotes proliferation of thyrocytes in vitro, and anti-TNF-α inhibits development of thyroid epithelial cell hyperplasia and proliferation in SCID recipients of IFN-γ(-/-) splenocytes. This suggests that targeting CD8(+) T cells and/or TNF-α may be effective for treating epithelial cell hyperplasia and fibrosis.

O uso do grupo focal em pesquisa qualitativa

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Lúcia Beatriz Ressel

2008-01-01

Full Text Available Este estudio tuvo como objetivo presentar el uso del grupo focal como técnica de recolección de datos en una tesis de doctorado, resultado de una investigación cualitativa. El grupo focal utiliza sesiones grupales de discusión, teniendo como foco central un tópico específico a ser debatido por los participantes. La investigación focalizó la temática de la sexualidad en la asistencia de enfermería, bajo una perspectiva cultural, siendo desarrollada con dos grupos de enfermeras: docentes y asistenciales. Comprendió ocho encuentros, y cada uno fue planeado por separado. La evaluación del proceso se realizó por medio de entrevistas con las enfermeras, destacando como puntos positivos la conducción hacia el pensamiento crítico y al proceso de desalineación; y la posibilidad de que esta técnica revele significados singulares y a que ellos se relacionen desde el punto de vista de los sujetos investigados. Esa técnica facilitó el abordaje de la sexualidad, desconstruyendo y reconstruyendo conceptos y buscando respuestas para las inquietudes del tema.

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.

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.

Characterizing T Cells in SCID Patients Presenting with Reactive or Residual T Lymphocytes

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Atar Lev

2012-01-01

Full Text Available Introduction. Patients with severe combined immunodeficiency (SCID may present with residual circulating T cells. While all cells are functionally deficient, resulting in high susceptibility to infections, only some of these cells are causing autoimmune symptoms. Methods. Here we compared T-cell functions including the number of circulating CD3+ T cells, in vitro responses to mitogens, T-cell receptor (TCR repertoire, TCR excision circles (TREC levels, and regulatory T cells (Tregs enumeration in several immunodeficinecy subtypes, clinically presenting with nonreactive residual cells (MHC-II deficiency or reactive cells. The latter includes patients with autoreactive clonal expanded T cell and patients with alloreactive transplacentally maternal T cells. Results. MHC-II deficient patients had slightly reduced T-cell function, normal TRECs, TCR repertoires, and normal Tregs enumeration. In contrast, patients with reactive T cells exhibited poor T-cell differentiation and activity. While the autoreactive cells displayed significantly reduced Tregs numbers, the alloreactive transplacentally acquired maternal lymphocytes had high functional Tregs. Conclusion. SCID patients presenting with circulating T cells show different patterns of T-cell activity and regulatory T cells enumeration that dictates the immunodeficient and autoimmune manifestations. We suggest that a high-tolerance capacity of the alloreactive transplacentally acquired maternal lymphocytes represents a toleration advantage, yet still associated with severe immunodeficiency.

Artificial intelligence may help in predicting the need for additional surgery after endoscopic resection of T1 colorectal cancer.

Science.gov (United States)

Ichimasa, Katsuro; Kudo, Shin-Ei; Mori, Yuichi; Misawa, Masashi; Matsudaira, Shingo; Kouyama, Yuta; Baba, Toshiyuki; Hidaka, Eiji; Wakamura, Kunihiko; Hayashi, Takemasa; Kudo, Toyoki; Ishigaki, Tomoyuki; Yagawa, Yusuke; Nakamura, Hiroki; Takeda, Kenichi; Haji, Amyn; Hamatani, Shigeharu; Mori, Kensaku; Ishida, Fumio; Miyachi, Hideyuki

2018-03-01

 Decisions concerning additional surgery after endoscopic resection of T1 colorectal cancer (CRC) are difficult because preoperative prediction of lymph node metastasis (LNM) is problematic. We investigated whether artificial intelligence can predict LNM presence, thus minimizing the need for additional surgery.  Data on 690 consecutive patients with T1 CRCs that were surgically resected in 2001 - 2016 were retrospectively analyzed. We divided patients into two groups according to date: data from 590 patients were used for machine learning for the artificial intelligence model, and the remaining 100 patients were included for model validation. The artificial intelligence model analyzed 45 clinicopathological factors and then predicted positivity or negativity for LNM. Operative specimens were used as the gold standard for the presence of LNM. The artificial intelligence model was validated by calculating the sensitivity, specificity, and accuracy for predicting LNM, and comparing these data with those of the American, European, and Japanese guidelines.  Sensitivity was 100 % (95 % confidence interval [CI] 72 % to 100 %) in all models. Specificity of the artificial intelligence model and the American, European, and Japanese guidelines was 66 % (95 %CI 56 % to 76 %), 44 % (95 %CI 34 % to 55 %), 0 % (95 %CI 0 % to 3 %), and 0 % (95 %CI 0 % to 3 %), respectively; and accuracy was 69 % (95 %CI 59 % to 78 %), 49 % (95 %CI 39 % to 59 %), 9 % (95 %CI 4 % to 16 %), and 9 % (95 %CI 4 % - 16 %), respectively. The rates of unnecessary additional surgery attributable to misdiagnosing LNM-negative patients as having LNM were: 77 % (95 %CI 62 % to 89 %) for the artificial intelligence model, and 85 % (95 %CI 73 % to 93 %; P  artificial intelligence significantly reduced unnecessary additional surgery after endoscopic resection of T1 CRC without missing LNM positivity. © Georg

Stress relaxing hyaluronic acid-collagen hydrogels promote cell spreading, fiber remodeling, and focal adhesion formation in 3D cell culture.

Science.gov (United States)

Lou, Junzhe; Stowers, Ryan; Nam, Sungmin; Xia, Yan; Chaudhuri, Ovijit

2018-02-01

The physical and architectural cues of the extracellular matrix (ECM) play a critical role in regulating important cellular functions such as spreading, migration, proliferation, and differentiation. Natural ECM is a complex viscoelastic scaffold composed of various distinct components that are often organized into a fibrillar microstructure. Hydrogels are frequently used as synthetic ECMs for 3D cell culture, but are typically elastic, due to covalent crosslinking, and non-fibrillar. Recent work has revealed the importance of stress relaxation in viscoelastic hydrogels in regulating biological processes such as spreading and differentiation, but these studies all utilize synthetic ECM hydrogels that are non-fibrillar. Key mechanotransduction events, such as focal adhesion formation, have only been observed in fibrillar networks in 3D culture to date. Here we present an interpenetrating network (IPN) hydrogel system based on HA crosslinked with dynamic covalent bonds and collagen I that captures the viscoelasticity and fibrillarity of ECM in tissues. The IPN hydrogels exhibit two distinct processes in stress relaxation, one from collagen and the other from HA crosslinking dynamics. Stress relaxation in the IPN hydrogels can be tuned by modulating HA crosslinker affinity, molecular weight of the HA, or HA concentration. Faster relaxation in the IPN hydrogels promotes cell spreading, fiber remodeling, and focal adhesion (FA) formation - behaviors often inhibited in other hydrogel-based materials in 3D culture. This study presents a new, broadly adaptable materials platform for mimicking key ECM features of viscoelasticity and fibrillarity in hydrogels for 3D cell culture and sheds light on how these mechanical and structural cues regulate cell behavior. Copyright © 2017 Elsevier Ltd. All rights reserved.

Human leucocyte antigen class I-redirected anti-tumour CD4+ T cells require a higher T cell receptor binding affinity for optimal activity than CD8+ T cells.

Science.gov (United States)

Tan, M P; Dolton, G M; Gerry, A B; Brewer, J E; Bennett, A D; Pumphrey, N J; Jakobsen, B K; Sewell, A K

2017-01-01

CD4 + T helper cells are a valuable component of the immune response towards cancer. Unfortunately, natural tumour-specific CD4 + T cells occur in low frequency, express relatively low-affinity T cell receptors (TCRs) and show poor reactivity towards cognate antigen. In addition, the lack of human leucocyte antigen (HLA) class II expression on most cancers dictates that these cells are often unable to respond to tumour cells directly. These deficiencies can be overcome by transducing primary CD4 + T cells with tumour-specific HLA class I-restricted TCRs prior to adoptive transfer. The lack of help from the co-receptor CD8 glycoprotein in CD4 + cells might result in these cells requiring a different optimal TCR binding affinity. Here we compared primary CD4 + and CD8 + T cells expressing wild-type and a range of affinity-enhanced TCRs specific for the HLA A*0201-restricted NY-ESO-1- and gp100 tumour antigens. Our major findings are: (i) redirected primary CD4 + T cells expressing TCRs of sufficiently high affinity exhibit a wide range of effector functions, including cytotoxicity, in response to cognate peptide; and (ii) optimal TCR binding affinity is higher in CD4 + T cells than CD8 + T cells. These results indicate that the CD4 + T cell component of current adoptive therapies using TCRs optimized for CD8 + T cells is below par and that there is room for substantial improvement. © 2016 The Authors. Clinical & Experimental Immunology published by John Wiley & Sons Ltd on behalf of British Society for Immunology.

Implementation of focal zooming on the Nike KrF laser

Energy Technology Data Exchange (ETDEWEB)

Kehne, D. M.; Karasik, M.; Weaver, J. L.; Chan, Y.; Obenschain, S. P. [Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375 (United States); Aglitsky, Y. [Science Applications International, McLean, Virginia 22150 (United States); Smyth, Z.; Lehmberg, R. H. [Research Support Instruments, Inc., Lanham, Maryland 20706 (United States); Terrell, S. [Commonwealth Technologies, Inc., Alexandria, Virginia 22315 (United States)

2013-01-15

In direct drive inertial confinement laser fusion, a pellet containing D-T fuel is imploded by ablation arising from absorption of laser energy at its outer surface. For optimal coupling, the focal spot of the laser would continuously decrease to match the reduction in the pellet's diameter, thereby minimizing wasted energy. A krypton-fluoride laser ({lambda}= 248 nm) that incorporates beam smoothing by induced spatial incoherence has the ability to produce a high quality focal profile whose diameter varies with time, a property known as focal zooming. A two-stage focal zoom has been demonstrated on the Nike laser at the Naval Research Laboratory. In the experiment, a 4.4 ns laser pulse was created in which the on-target focal spot diameter was 1.3 mm (full width at half maximum) for the first 2.4 ns and 0.28 mm for the final 2 ns. These two diameters appear in time-integrated focal plane equivalent images taken at several locations in the amplification chain. Eight of the zoomed output beams were overlapped on a 60 {mu}m thick planar polystyrene target. Time resolved images of self-emission from the rear of the target show the separate shocks launched by the two corresponding laser focal diameters.

Implementation of focal zooming on the Nike KrF laser

International Nuclear Information System (INIS)

Kehne, D. M.; Karasik, M.; Weaver, J. L.; Chan, Y.; Obenschain, S. P.; Aglitsky, Y.; Smyth, Z.; Lehmberg, R. H.; Terrell, S.

2013-01-01

In direct drive inertial confinement laser fusion, a pellet containing D-T fuel is imploded by ablation arising from absorption of laser energy at its outer surface. For optimal coupling, the focal spot of the laser would continuously decrease to match the reduction in the pellet's diameter, thereby minimizing wasted energy. A krypton-fluoride laser (λ= 248 nm) that incorporates beam smoothing by induced spatial incoherence has the ability to produce a high quality focal profile whose diameter varies with time, a property known as focal zooming. A two-stage focal zoom has been demonstrated on the Nike laser at the Naval Research Laboratory. In the experiment, a 4.4 ns laser pulse was created in which the on-target focal spot diameter was 1.3 mm (full width at half maximum) for the first 2.4 ns and 0.28 mm for the final 2 ns. These two diameters appear in time-integrated focal plane equivalent images taken at several locations in the amplification chain. Eight of the zoomed output beams were overlapped on a 60 μm thick planar polystyrene target. Time resolved images of self-emission from the rear of the target show the separate shocks launched by the two corresponding laser focal diameters.

Implementation of focal zooming on the Nike KrF laser

Science.gov (United States)

Kehne, D. M.; Karasik, M.; Aglitsky, Y.; Smyth, Z.; Terrell, S.; Weaver, J. L.; Chan, Y.; Lehmberg, R. H.; Obenschain, S. P.

2013-01-01

In direct drive inertial confinement laser fusion, a pellet containing D-T fuel is imploded by ablation arising from absorption of laser energy at its outer surface. For optimal coupling, the focal spot of the laser would continuously decrease to match the reduction in the pellet's diameter, thereby minimizing wasted energy. A krypton-fluoride laser (λ = 248 nm) that incorporates beam smoothing by induced spatial incoherence has the ability to produce a high quality focal profile whose diameter varies with time, a property known as focal zooming. A two-stage focal zoom has been demonstrated on the Nike laser at the Naval Research Laboratory. In the experiment, a 4.4 ns laser pulse was created in which the on-target focal spot diameter was 1.3 mm (full width at half maximum) for the first 2.4 ns and 0.28 mm for the final 2 ns. These two diameters appear in time-integrated focal plane equivalent images taken at several locations in the amplification chain. Eight of the zoomed output beams were overlapped on a 60 μm thick planar polystyrene target. Time resolved images of self-emission from the rear of the target show the separate shocks launched by the two corresponding laser focal diameters.

FoxP3+ regulatory T cells are distinct from leukemia cells in HTLV-1-associated adult T-cell leukemia.

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Toulza, Frederic; Nosaka, Kisato; Takiguchi, Masafumi; Pagliuca, Tony; Mitsuya, Hiroaki; Tanaka, Yuetsu; Taylor, Graham P; Bangham, Charles R M

2009-11-15

Human T-lymphotropic virus type 1 (HTLV-1) is the causative agent of adult T-cell leukemia/lymphoma (ATLL). It has been postulated that ATLL cells might act as regulatory T cells (T(regs)) which, in common with ATLL cells, express both CD25 and FoxP3, and so contribute to the severe immune suppression typical of ATLL. We report here that the frequency of CD25(+) cells varied independently of the frequency of FoxP3(+) cells in both a cross-sectional study and in a longitudinal study of 2 patients with chronic ATLL. Furthermore, the capacity of ATLL cells to suppress proliferation of heterologous CD4(+)CD25(-) cells correlated with the frequency of CD4(+) FoxP3(+) cells but was independent of CD25 expression. Finally, the frequency of CD4(+)FoxP3(+) cells was inversely correlated with the lytic activity of HTLV-1-specific CTLs in patients with ATLL. We conclude that ATLL is not a tumor of FoxP3(+) regulatory T cells, and that a population of FoxP3(+) cells distinct from ATLL cells has regulatory functions and may impair the cell-mediated immune response to HTLV-1 in patients with ATLL.

Co-Expansion of Cytokine-Induced Killer Cells and Vγ9Vδ2 T Cells for CAR T-Cell Therapy.

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Shou-Hui Du

Full Text Available Gamma delta (γδ T cells and cytokine-induced killer (CIK cells, which are a heterogeneous population of T lymphocytes and natural killer T (NKT cells, have been separately expanded ex vivo and shown to be capable of targeting and mediating cytotoxicity against various tumor cells in a major histocompatibility complex-unrestricted manner. However, the co-expansion and co-administration of these immune cells have not been explored. In this study we describe an efficient method to expand simultaneously both CIK and Vγ9Vδ2 T cells, termed as CIKZ cells, from human peripheral blood mononuclear cells (PBMCs using Zometa, interferon-gamma (IFN-γ, interleukin 2 (IL-2, anti-CD3 antibody and engineered K562 feeder cells expressing CD64, CD137L and CD86. A 21-day culture of PBMCs with this method yielded nearly 20,000-fold expansion of CIKZ cells with γδ T cells making up over 20% of the expanded population. The expanded CIKZ cells exhibited antitumor cytotoxicity and could be modified to express anti-CD19 chimeric antigen receptor (CAR, anti-CEA CAR, and anti-HER2 CAR to enhance their specificity and cytotoxicity against CD19-, CEA-, or HER2-positive tumor cells. The tumor inhibitory activity of anti-CD19 CAR-modified CIKZ cells was further demonstrated in vivo in a Raji tumor mouse model. The findings herein substantiate the feasibility of co-expanding CIK and γδ cells for adoptive cellular immunotherapy applications such as CAR T-cell therapy against cancer.

The parietal epithelial cell is crucially involved in human idiopathic focal segmental glomerulosclerosis.

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Dijkman, Henry; Smeets, Bart; van der Laak, Jeroen; Steenbergen, Eric; Wetzels, Jack

2005-10-01

Focal segmental glomerulosclerosis (FSGS) is one of the most common patterns of glomerular injury encountered in human renal biopsies. Epithelial hyperplasia, which can be prominent in FSGS, has been attributed to dedifferentiation and proliferation of podocytes. Based on observations in a mouse model of FSGS, we pointed to the role of parietal epithelial cells (PECs). In the present study we investigated the relative role of PECs and podocytes in human idiopathic FSGS. We performed a detailed study of lesions from a patient with recurrent idiopathic FSGS by serial sectioning, marker analysis and three-dimensional reconstruction of glomeruli. We have studied the expression of markers for podocytes, PECs, mesangial cells, endothelium, and myofibroblasts. We also looked at proliferation and composition of the deposited extracellular matrix (ECM). We found that proliferating epithelial cells in FSGS lesions are negative for podocyte and macrophage markers, but stain for PEC markers. The composition of the matrix deposited by these cells is identical to Bowman's capsule. Our study demonstrates that PECs are crucially involved in the pathogenesis of FSGS lesions.

Triplet–triplet energy transfer in artificial and natural photosynthetic antennas

OpenAIRE

Ho, Junming; Kish, Elizabeth; Méndez-Hernández, Dalvin D.; WongCarter, Katherine; Pillai, Smitha; Kodis, Gerdenis; Niklas, Jens; Poluektov, Oleg G.; Gust, Devens; Moore, Thomas A.; Moore, Ana L.; Batista, Victor S.; Robert, Bruno

2017-01-01

Rapid chlorophyll-to-carotenoid triplet–triplet energy transfer (T-TET) in photosynthetic organisms is crucial to photoprotection from singlet oxygen. Photosynthesis reengineered for increased efficiency will result in increased oxygen levels in the cells, and the need to ensure adequately rapid T-TET will arise. Using a combination of theoretical and experimental studies on artificial and natural carotenoid–chlorophyll complexes, we have identified spectroscopic markers indicative of specifi...

Focal myositis

International Nuclear Information System (INIS)

Kransdorf, M.J.; Temple, H.T.; Sweet, D.E.

1998-01-01

Focal myositis is a pseudotumor of soft tissue that typically occurs in the deep soft tissue of the extremities, and is a relatively rare lesion. There is a wide clinical spectrum, with approximately one-third of patients with focal myositis subsequently developing polymyositis, and clinical symptoms of generalized weakness, fever, myalgia, and weight loss, with elevation of creatine phosphokinase. We report the case of a patient with focal myositis who subsequently developed myositis ossificans-like features. (orig.)

Leukemia-Initiating Cells in T-Cell Acute Lymphoblastic Leukemia.

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Tan, Shi Hao; Bertulfo, Fatima Carla; Sanda, Takaomi

2017-01-01

T-cell acute lymphoblastic leukemia (T-ALL) is a hematological malignancy characterized by the clonal proliferation of immature T-cell precursors. T-ALL has many similar pathophysiological features to acute myeloid leukemia, which has been extensively studied in the establishment of the cancer stem cell (CSC) theory, but the CSC concept in T-ALL is still debatable. Although leukemia-initiating cells (LICs), which can generate leukemia in a xenograft setting, have been found in both human T-ALL patients and animal models, the nature and origin of LICs are largely unknown. In this review, we discuss recent studies on LICs in T-ALL and the potential mechanisms of LIC emergence in this disease. We focus on the oncogenic transcription factors TAL1, LMO2 , and NOTCH1 and highlight the significance of the transcriptional regulatory programs in normal hematopoietic stem cells and T-ALL.

Leukemia-Initiating Cells in T-Cell Acute Lymphoblastic Leukemia

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Shi Hao Tan

2017-09-01

Full Text Available T-cell acute lymphoblastic leukemia (T-ALL is a hematological malignancy characterized by the clonal proliferation of immature T-cell precursors. T-ALL has many similar pathophysiological features to acute myeloid leukemia, which has been extensively studied in the establishment of the cancer stem cell (CSC theory, but the CSC concept in T-ALL is still debatable. Although leukemia-initiating cells (LICs, which can generate leukemia in a xenograft setting, have been found in both human T-ALL patients and animal models, the nature and origin of LICs are largely unknown. In this review, we discuss recent studies on LICs in T-ALL and the potential mechanisms of LIC emergence in this disease. We focus on the oncogenic transcription factors TAL1, LMO2, and NOTCH1 and highlight the significance of the transcriptional regulatory programs in normal hematopoietic stem cells and T-ALL.

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

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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.

T cell ignorance is bliss: T cells are not tolerized by Langerhans cells presenting human papillomavirus antigens in the absence of costimulation

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Andrew W. Woodham

2016-12-01

Full Text Available Human papillomavirus type 16 (HPV16 infections are intra-epithelial, and thus, HPV16 is known to interact with Langerhans cells (LCs, the resident epithelial antigen-presenting cells (APCs. The current paradigm for APC-mediated induction of T cell anergy is through delivery of T cell receptor signals via peptides on MHC molecules (signal 1, but without costimulation (signal 2. We previously demonstrated that LCs exposed to HPV16 in vitro present HPV antigens to T cells without costimulation, but it remained uncertain if such T cells would remain ignorant, become anergic, or in the case of CD4+ T cells, differentiate into Tregs. Here we demonstrate that Tregs were not induced by LCs presenting only signal 1, and through a series of in vitro immunizations show that CD8+ T cells receiving signal 1+2 from LCs weeks after consistently receiving signal 1 are capable of robust effector functions. Importantly, this indicates that T cells are not tolerized but instead remain ignorant to HPV, and are activated given the proper signals. Keywords: T cell anergy, T cell ignorance, Immune tolerance, Human papillomavirus, HPV16, Langerhans cells

Functional and genomic analyses of FOXP3-transduced Jurkat-T cells as regulatory T (Treg)-like cells

International Nuclear Information System (INIS)

Kim, Joon-Young; Kim, Han-Jong; Hurt, Elaine M.; Chen, Xin; Howard, O.M. Zack; Farrar, William L.

2007-01-01

FOXP3, a forkhead transcription factor is essential for the development and function of CD4 + CD25 + regulatory T cells (Tregs). In contrast to conversion of murine naive T cells to Tregs by transduction of Foxp3, it is controversial whether ectopic expression of FOXP3 in human CD4 + T cells is sufficient for acquisition of suppressive activity. Here, we show that retroviral transduction of FOXP3 induces a Treg phenotype in human leukemic CD4 + Jurkat-T cells, evidenced by increased expression of Treg-associated cell surface markers as well as inhibition of cytokine production. Furthermore, FOXP3-transduced Jurkat-T cells suppress the proliferation of human CD4 + CD25 - T cells. Additionally, DNA microarray analysis identifies Treg-related genes regulated by FOXP3. Our study demonstrates that enforced expression of FOXP3 confers Treg-like properties on Jurkat-T cells, which can be a convenient and efficient Treg-like cell model for further study to identify Treg cell surface markers and target genes regulated by FOXP3

Termination of T cell priming relies on a phase of unresponsiveness promoting disengagement from APCs and T cell division.

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Bohineust, Armelle; Garcia, Zacarias; Beuneu, Hélène; Lemaître, Fabrice; Bousso, Philippe

2018-05-07

T cells are primed in secondary lymphoid organs by establishing stable interactions with antigen-presenting cells (APCs). However, the cellular mechanisms underlying the termination of T cell priming and the initiation of clonal expansion remain largely unknown. Using intravital imaging, we observed that T cells typically divide without being associated to APCs. Supporting these findings, we demonstrate that recently activated T cells have an intrinsic defect in establishing stable contacts with APCs, a feature that was reflected by a blunted capacity to stop upon T cell receptor (TCR) engagement. T cell unresponsiveness was caused, in part, by a general block in extracellular calcium entry. Forcing TCR signals in activated T cells antagonized cell division, suggesting that T cell hyporesponsiveness acts as a safeguard mechanism against signals detrimental to mitosis. We propose that transient unresponsiveness represents an essential phase of T cell priming that promotes T cell disengagement from APCs and favors effective clonal expansion. © 2018 Bohineust et al.

c-MPL provides tumor-targeted T-cell receptor-transgenic T cells with costimulation and cytokine signals.

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Nishimura, Christopher D; Brenner, Daniel A; Mukherjee, Malini; Hirsch, Rachel A; Ott, Leah; Wu, Meng-Fen; Liu, Hao; Dakhova, Olga; Orange, Jordan S; Brenner, Malcolm K; Lin, Charles Y; Arber, Caroline

2017-12-21

Adoptively transferred T-cell receptor (TCR)-engineered T cells depend on host-derived costimulation and cytokine signals for their full and sustained activation. However, in patients with cancer, both signals are frequently impaired. Hence, we developed a novel strategy that combines both essential signals in 1 transgene by expressing the nonlymphoid hematopoietic growth factor receptor c-MPL (myeloproliferative leukemia), the receptor for thrombopoietin (TPO), in T cells. c-MPL signaling activates pathways shared with conventional costimulatory and cytokine receptor signaling. Thus, we hypothesized that host-derived TPO, present in the tumor microenvironment, or pharmacological c-MPL agonists approved by the US Food and Drug Administration could deliver both signals to c-MPL-engineered TCR-transgenic T cells. We found that c-MPL + polyclonal T cells expand and proliferate in response to TPO, and persist longer after adoptive transfer in immunodeficient human TPO-transgenic mice. In TCR-transgenic T cells, c-MPL activation enhances antitumor function, T-cell expansion, and cytokine production and preserves a central memory phenotype. c-MPL signaling also enables sequential tumor cell killing, enhances the formation of effective immune synapses, and improves antileukemic activity in vivo in a leukemia xenograft model. We identify the type 1 interferon pathway as a molecular mechanism by which c-MPL mediates immune stimulation in T cells. In conclusion, we present a novel immunotherapeutic strategy using c-MPL-enhanced transgenic T cells responding to either endogenously produced TPO (a microenvironment factor in hematologic malignancies) or c-MPL-targeted pharmacological agents. © 2017 by The American Society of Hematology.

Tumor-specific CD4+ T cells develop cytotoxic activity and eliminate virus-induced tumor cells in the absence of regulatory T cells.

Science.gov (United States)

Akhmetzyanova, Ilseyar; Zelinskyy, Gennadiy; Schimmer, Simone; Brandau, Sven; Altenhoff, Petra; Sparwasser, Tim; Dittmer, Ulf

2013-02-01

The important role of tumor-specific cytotoxic CD8(+) T cells is well defined in the immune control of the tumors, but the role of effector CD4(+) T cells is poorly understood. In the current research, we have used a murine retrovirus-induced tumor cell line of C57BL/6 mouse origin, namely FBL-3 cells, as a model to study basic mechanisms of immunological control and escape during tumor formation. This study shows that tumor-specific CD4(+) T cells are able to protect against virus-induced tumor cells. We show here that there is an expansion of tumor-specific CD4(+) T cells producing cytokines and cytotoxic molecule granzyme B (GzmB) in the early phase of tumor growth. Importantly, we demonstrate that in vivo depletion of regulatory T cells (Tregs) and CD8(+) T cells in FBL-3-bearing DEREG transgenic mice augments IL-2 and GzmB production by CD4(+) T cells and increases FV-specific CD4(+) T-cell effector and cytotoxic responses leading to the complete tumor regression. Therefore, the capacity to reject tumor acquired by tumor-reactive CD4(+) T cells largely depends on the direct suppressive activity of Tregs. We suggest that a cytotoxic CD4(+) T-cell immune response may be induced to enhance resistance against oncovirus-associated tumors.

Immunobiology of T cell responses to Mls-locus-disparate stimulator cells. III. Helper and cytolytic functions of cloned, Mls-reactive T cell lines

International Nuclear Information System (INIS)

Katz, M.E.; Tite, J.P.; Janeway, C.A. Jr.

1986-01-01

Mls-specific T cell clones derived by limiting dilution were tested for cytotoxic activity in a lectin-dependent 51 Cr-release assay. All the T cell clones tested were cytotoxic in such an assay in apparent contrast to previous reports (1, 2). However, only those target cells sensitive to cytolysis by other L3T4a + cytolytic T cells (3) were killed by Mls-specific T cell clones in short term 51 Cr-release assays, possibly explaining this discrepancy. All the T cell clones tested were L3T4a + ,Lyt-2 - and stimulated B cells from Mls strains of mice to proliferate and secrete immunoglobulin. Furthermore, lysis of innocent bystander targets was observed when the T cells were stimulated with Mls-disparate stimulator cells. These results are consistent with those obtained with L3T4a - T cells specific for protein antigen:self Ia and that express cytotoxic potential (3)

Altered development of NKT cells, γδ T cells, CD8 T cells and NK cells in a PLZF deficient patient.

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Maggie Eidson

Full Text Available In mice, the transcription factor, PLZF, controls the development of effector functions in invariant NKT cells and a subset of NKT cell-like, γδ T cells. Here, we show that in human lymphocytes, in addition to invariant NKT cells, PLZF was also expressed in a large percentage of CD8+ and CD4+ T cells. Furthermore, PLZF was also found to be expressed in all γδ T cells and in all NK cells. Importantly, we show that in a donor lacking functional PLZF, all of these various lymphocyte populations were altered. Therefore, in contrast to mice, PLZF appears to control the development and/or function of a wide variety of human lymphocytes that represent more than 10% of the total PBMCs. Interestingly, the PLZF-expressing CD8+ T cell population was found to be expanded in the peripheral blood of patients with metastatic melanoma but was greatly diminished in patients with autoimmune disease.

Bacterial CpG-DNA activates dendritic cells in vivo: T helper cell-independent cytotoxic T cell responses to soluble proteins.

Science.gov (United States)

Sparwasser, T; Vabulas, R M; Villmow, B; Lipford, G B; Wagner, H

2000-12-01

Receptors for conserved molecular patterns associated with microbial pathogens induce synthesis of co-stimulatory molecules and cytokines in immature dendritic cells (DC), as do antigen-reactive CD4 T helper cells via CD40 signaling. Once activated, antigen-presenting DC may activate CD8 T cell responses in a T helper cell-independent fashion. Using immunostimulatory CpG-oligonucleotides (ODN) mimicking bacterial CpG-DNA, we tested whether CpG-DNA bypasses the need for T helper cells in CTL responses towards proteins by directly activating antigen-presenting DC to transit into professional APC. We describe that immature DC in situ constitutively process soluble proteins and generate CD8 T cell determinants yet CD8 T cell responses remain abortive. Induction of primary antigen-specific CD8 cytotoxic T lymphocyte (CTL)-mediated responses becomes initiated in wild-type as well as T helper cell-deficient mice, provided soluble protein and CpG-ODN are draining into the same lymph node. Specifically we show that CpG-ODN trigger antigen-presenting immature DC within the draining lymph node to acutely up-regulate co-stimulatory molecules and produce IL-12. These results provide new insights for generating in vivo efficient CTL responses to soluble proteins which may influence vaccination strategies.

Focal myositis

Energy Technology Data Exchange (ETDEWEB)

Kransdorf, M.J. [Saint Mary`s Hospital, Richmond, VA (United States). Dept. of Radiol.]|[Department of Radiologic Pathology, Armed Forces Institute of Pathology, Washington, DC (United States); Temple, H.T. [Department of Orthopedic Surgery, University of Virginia Health Sciences Center, Charlottesville, Virginia (United States)]|[Department of Orthopedic Pathology, Armed Forces Institute of Pathology, Washington, DC (United States); Sweet, D.E. [Department of Orthopedic Pathology, Armed Forces Institute of Pathology, Washington, DC (United States)

1998-05-01

Focal myositis is a pseudotumor of soft tissue that typically occurs in the deep soft tissue of the extremities, and is a relatively rare lesion. There is a wide clinical spectrum, with approximately one-third of patients with focal myositis subsequently developing polymyositis, and clinical symptoms of generalized weakness, fever, myalgia, and weight loss, with elevation of creatine phosphokinase. We report the case of a patient with focal myositis who subsequently developed myositis ossificans-like features. (orig.) With 3 figs., 25 refs.

Blockade of CD7 expression in T cells for effective chimeric antigen receptor targeting of T-cell malignancies.

Science.gov (United States)

Png, Yi Tian; Vinanica, Natasha; Kamiya, Takahiro; Shimasaki, Noriko; Coustan-Smith, Elaine; Campana, Dario

2017-11-28

Effective immunotherapies for T-cell malignancies are lacking. We devised a novel approach based on chimeric antigen receptor (CAR)-redirected T lymphocytes. We selected CD7 as a target because of its consistent expression in T-cell acute lymphoblastic leukemia (T-ALL), including the most aggressive subtype, early T-cell precursor (ETP)-ALL. In 49 diagnostic T-ALL samples (including 14 ETP-ALL samples), median CD7 expression was >99%; CD7 expression remained high at relapse (n = 14), and during chemotherapy (n = 54). We targeted CD7 with a second-generation CAR (anti-CD7-41BB-CD3ζ), but CAR expression in T lymphocytes caused fratricide due to the presence of CD7 in the T cells themselves. To downregulate CD7 and control fratricide, we applied a new method (protein expression blocker [PEBL]), based on an anti-CD7 single-chain variable fragment coupled with an intracellular retention domain. Transduction of anti-CD7 PEBL resulted in virtually instantaneous abrogation of surface CD7 expression in all transduced T cells; 2.0% ± 1.7% were CD7 + vs 98.1% ± 1.5% of mock-transduced T cells (n = 5; P < .0001). PEBL expression did not impair T-cell proliferation, interferon-γ and tumor necrosis factor-α secretion, or cytotoxicity, and eliminated CAR-mediated fratricide. PEBL-CAR T cells were highly cytotoxic against CD7 + leukemic cells in vitro and were consistently more potent than CD7 + T cells spared by fratricide. They also showed strong anti-leukemic activity in cell line- and patient-derived T-ALL xenografts. The strategy described in this study fits well with existing clinical-grade cell manufacturing processes and can be rapidly implemented for the treatment of patients with high-risk T-cell malignancies.

Immature MEF2C-dysregulated T-cell leukemia patients have an early T-cell precursor acute lymphoblastic leukemia gene signature and typically have non-rearranged T-cell receptors

Science.gov (United States)

Zuurbier, Linda; Gutierrez, Alejandro; Mullighan, Charles G.; Canté-Barrett, Kirsten; Gevaert, A. Olivier; de Rooi, Johan; Li, Yunlei; Smits, Willem K.; Buijs-Gladdines, Jessica G.C.A.M.; Sonneveld, Edwin; Look, A. Thomas; Horstmann, Martin; Pieters, Rob; Meijerink, Jules P.P.

2014-01-01

Three distinct immature T-cell acute lymphoblastic leukemia entities have been described including cases that express an early T-cell precursor immunophenotype or expression profile, immature MEF2C-dysregulated T-cell acute lymphoblastic leukemia cluster cases based on gene expression analysis (immature cluster) and cases that retain non-rearranged TRG@ loci. Early T-cell precursor acute lymphoblastic leukemia cases exclusively overlap with immature cluster samples based on the expression of early T-cell precursor acute lymphoblastic leukemia signature genes, indicating that both are featuring a single disease entity. Patients lacking TRG@ rearrangements represent only 40% of immature cluster cases, but no further evidence was found to suggest that cases with absence of bi-allelic TRG@ deletions reflect a distinct and even more immature disease entity. Immature cluster/early T-cell precursor acute lymphoblastic leukemia cases are strongly enriched for genes expressed in hematopoietic stem cells as well as genes expressed in normal early thymocyte progenitor or double negative-2A T-cell subsets. Identification of early T-cell precursor acute lymphoblastic leukemia cases solely by defined immunophenotypic criteria strongly underestimates the number of cases that have a corresponding gene signature. However, early T-cell precursor acute lymphoblastic leukemia samples correlate best with a CD1 negative, CD4 and CD8 double negative immunophenotype with expression of CD34 and/or myeloid markers CD13 or CD33. Unlike various other studies, immature cluster/early T-cell precursor acute lymphoblastic leukemia patients treated on the COALL-97 protocol did not have an overall inferior outcome, and demonstrated equal sensitivity levels to most conventional therapeutic drugs compared to other pediatric T-cell acute lymphoblastic leukemia patients. PMID:23975177

Immunoregulatory T cells in man. Histamine-induced suppressor T cells are derived from a Leu 2+ (T8+) subpopulation distinct from that which gives rise to cytotoxic T cells

International Nuclear Information System (INIS)

Sansoni, P.; Silverman, E.D.; Khan, M.M.; Melmon, K.L.; Engleman, E.G.

1985-01-01

One mechanism of histamine-mediated inhibition of the immune response in man is to activate T suppressor cells that bear the Leu 2 (OKT8) marker. The current study was undertaken to characterize the histamine-induced suppressor cell using a monoclonal antibody (9.3) shown previously to distinguish cytotoxic T cells from antigen-specific suppressor T cells. Leu 2+ cells isolated from peripheral blood were further separated with antibody 9.3 into Leu 2+, 9.3+, and Leu 2+, 9.3- subsets and each subset was incubated with different concentrations of histamine before determining their ability to suppress immune responses in vitro. The results indicate that the Leu 2+, 9.3- subpopulation includes all histamine-induced suppressor cells, that 10(-4) M histamine is the optimal concentration for suppressor cell induction, and that exposure of Leu 2+, 9.3- cells to histamine for 30 s is sufficient to initiate the induction process. After treatment with histamine these cells inhibit both phytohemagglutinin-induced T cell proliferation and pokeweed mitogen-induced B cell differentiation. The suppression of phytohemagglutinin-induced proliferation was resistant to x-irradiation with 1,200 rad, either before or after histamine exposure, suggesting that Leu 2+, 9.3- cells need not proliferate to become suppressor cells or exert suppression. Moreover, suppression by these cells was not due to altered kinetics of the response. Finally, a histamine type 2 receptor antagonist (cimetidine) but not a type 1 receptor antagonist (mepyramine) blocked the induction of suppressor cells. On the basis of these results and our previous studies of antigen specific suppressor cells, we conclude that Leu 2+ suppressor cells in man are derived from a precursor pool that is phenotypically distinct from cells that can differentiate into cytotoxic T cells

Dual role of miR-21 in CD4+ T-cells: activation-induced miR-21 supports survival of memory T-cells and regulates CCR7 expression in naive T-cells.

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Katarzyna Smigielska-Czepiel

Full Text Available Immune cell-type specific miRNA expression patterns have been described but the detailed role of single miRNAs in the function of T-cells remains largely unknown. We investigated the role of miR-21 in the function of primary human CD4+ T-cells. MiR-21 is substantially expressed in T-cells with a memory phenotype, and is robustly upregulated upon αCD3/CD28 activation of both naive and memory T-cells. By inhibiting the endogenous miR-21 function in activated naive and memory T-cells, we showed that miR-21 regulates fundamentally different aspects of T-cell biology, depending on the differentiation status of the T-cell. Stable inhibition of miR-21 function in activated memory T-cells led to growth disadvantage and apoptosis, indicating that the survival of memory T-cells depends on miR-21 function. In contrast, stable inhibition of miR-21 function in activated naive T-cells did not result in growth disadvantage, but led to a significant induction of CCR7 protein expression. Direct interaction between CCR7 and miR-21 was confirmed in a dual luciferase reporter assay. Our data provide evidence for a dual role of miR-21 in CD4+ T cells; Regulation of T-cell survival is confined to activated memory T-cells, while modulation of potential homing properties, through downregulation of CCR7 protein expression, is observed in activated naive T-cells.

CD4 T cells play important roles in maintaining IL-17-producing γδ T-cell subsets in naive animals.

Science.gov (United States)

Do, Jeong-Su; Visperas, Anabelle; O'Brien, Rebecca L; Min, Booki

2012-04-01

A proportional balance between αβ and γδ T-cell subsets in the periphery is exceedingly well maintained by a homeostatic mechanism. However, a cellular mechanism underlying the regulation remains undefined. We recently reported that a subset of developing γδ T cells spontaneously acquires interleukin (IL)-17-producing capacity even within naive animals through a transforming growth factor (TGF)β1-dependent mechanism, thus considered 'innate' IL-17-producing cells. Here, we report that γδ T cells generated within αβ T cell (or CD4 T cell)-deficient environments displayed altered cytokine profiles; particularly, 'innate' IL-17 expression was significantly impaired compared with those in wild-type mice. Impaired IL-17 production in γδ T cells was directly related to CD4 T-cell deficiency, because depletion of CD4 T cells in wild-type mice diminished and adoptive CD4 T-cell transfer into T-cell receptor β-/- mice restored IL-17 expression in γδ T cells. CD4 T cell-mediated IL-17 expression required TGFβ1. Moreover, Th17 but not Th1 or Th2 effector CD4 T cells were highly efficient in enhancing γδ T-cell IL-17 expression. Taken together, our results highlight a novel CD4 T cell-dependent mechanism that shapes the generation of IL-17+ γδ T cells in naive settings.

Earthquake focal mechanism forecasting in Italy for PSHA purposes

Science.gov (United States)

Roselli, Pamela; Marzocchi, Warner; Mariucci, Maria Teresa; Montone, Paola

2018-01-01

In this paper, we put forward a procedure that aims to forecast focal mechanism of future earthquakes. One of the primary uses of such forecasts is in probabilistic seismic hazard analysis (PSHA); in fact, aiming at reducing the epistemic uncertainty, most of the newer ground motion prediction equations consider, besides the seismicity rates, the forecast of the focal mechanism of the next large earthquakes as input data. The data set used to this purpose is relative to focal mechanisms taken from the latest stress map release for Italy containing 392 well-constrained solutions of events, from 1908 to 2015, with Mw ≥ 4 and depths from 0 down to 40 km. The data set considers polarity focal mechanism solutions until to 1975 (23 events), whereas for 1976-2015, it takes into account only the Centroid Moment Tensor (CMT)-like earthquake focal solutions for data homogeneity. The forecasting model is rooted in the Total Weighted Moment Tensor concept that weighs information of past focal mechanisms evenly distributed in space, according to their distance from the spatial cells and magnitude. Specifically, for each cell of a regular 0.1° × 0.1° spatial grid, the model estimates the probability to observe a normal, reverse, or strike-slip fault plane solution for the next large earthquakes, the expected moment tensor and the related maximum horizontal stress orientation. These results will be available for the new PSHA model for Italy under development. Finally, to evaluate the reliability of the forecasts, we test them with an independent data set that consists of some of the strongest earthquakes with Mw ≥ 3.9 occurred during 2016 in different Italian tectonic provinces.

Phosphoinositide 3–kinase γ participates in T cell receptor–induced T cell activation

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Alcázar, Isabela; Marqués, Miriam; Kumar, Amit; Hirsch, Emilio; Wymann, Matthias; Carrera, Ana C.; Barber, Domingo F.

2007-01-01

Class I phosphoinositide 3–kinases (PI3Ks) constitute a family of enzymes that generates 3-phosphorylated polyphosphoinositides at the cell membrane after stimulation of protein tyrosine (Tyr) kinase–associated receptors or G protein–coupled receptors (GPCRs). The class I PI3Ks are divided into two types: class IA p85/p110 heterodimers, which are activated by Tyr kinases, and the class IB p110γ isoform, which is activated by GPCR. Although the T cell receptor (TCR) is a protein Tyr kinase–associated receptor, p110γ deletion affects TCR-induced T cell stimulation. We examined whether the TCR activates p110γ, as well as the consequences of interfering with p110γ expression or function for T cell activation. We found that after TCR ligation, p110γ interacts with Gαq/11, lymphocyte-specific Tyr kinase, and ζ-associated protein. TCR stimulation activates p110γ, which affects 3-phosphorylated polyphosphoinositide levels at the immunological synapse. We show that TCR-stimulated p110γ controls RAS-related C3 botulinum substrate 1 activity, F-actin polarization, and the interaction between T cells and antigen-presenting cells, illustrating a crucial role for p110γ in TCR-induced T cell activation. PMID:17998387

Constrained Adherable Area of Nanotopographic Surfaces Promotes Cell Migration through the Regulation of Focal Adhesion via Focal Adhesion Kinase/Rac1 Activation.

Science.gov (United States)

Lim, Jiwon; Choi, Andrew; Kim, Hyung Woo; Yoon, Hyungjun; Park, Sang Min; Tsai, Chia-Hung Dylan; Kaneko, Makoto; Kim, Dong Sung

2018-05-02

Cell migration is crucial in physiological and pathological processes such as embryonic development and wound healing; such migration is strongly guided by the surrounding nanostructured extracellular matrix. Previous studies have extensively studied the cell migration on anisotropic nanotopographic surfaces; however, only a few studies have reported cell migration on isotropic nanotopographic surfaces. We herein, for the first time, propose a novel concept of adherable area on cell migration using isotropic nanopore surfaces with sufficient nanopore depth by adopting a high aspect ratio. As the pore size of the nanopore surface was controlled to 200, 300, and 400 nm in a fixed center-to-center distance of 480 nm, it produced 86, 68, and 36% of adherable area, respectively, on the fabricated surface. A meticulous investigation of the cell migration in response to changes in the constrained adherable area of the nanotopographic surface showed 1.4-, 1.5-, and 1.6-fold increase in migration speeds and a 1.4-, 2-, and 2.5-fold decrease in the number of focal adhesions as the adherable area was decreased to 86, 68, and 36%, respectively. Furthermore, a strong activation of FAK/Rac1 signaling was observed to be involved in the promoted cell migration. These results suggest that the reduced adherable area promotes cell migration through decreasing the FA formation, which in turn upregulates FAK/Rac1 activation. The findings in this study can be utilized to control the cell migration behaviors, which is a powerful tool in the research fields involving cell migration such as promoting wound healing and tissue repair.

T-cell epitopes from viral and tumor associated antigens: induction and analysis of antigen-specific T cells

OpenAIRE

Nastke, Maria-Dorothea

2005-01-01

T cells are important effectors in the defense of human pathogens entering the organism. CD8+ T cells recognize peptides which are presented by MHC class I molecules and lyse cells which are infected by virus or intracellular pathogens. Moreover, they are able to destroy cancer cells. CD4+ T cells recognize peptides from exogenous proteins acquired by endocytosis or from internalized plasma membrane proteins which are presented on MHC class II. CD4+ T cells play an important role in the defen...

The interaction of dendritic cells and γδ T cells promotes the activation of γδ T cells in experimental autoimmune uveitis

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Beibei Wang

2017-03-01

Full Text Available Uveitis is a severe inflammatory disease that can cause visual impairment. Recently, activated γδ T cells were proved to play a central role in the development of experimental autoimmune uveitis (EAU. However, the mechanism underlying γδ T-cell activation in EAU is incompletely known. In this study, we determined the percentage changes in and the phenotypes of γδ T cells and dendritic cells (DCs obtained from the spleens of immunized C57BL/6 (B6 mice, an animal model of EAU. We found that the number of γδ T cells and DCs obviously increased during the inflammation phase of EAU (days 16–20 of our experiment, and that during this time, γδ T cells expressed high levels of CD69 and the integrin lymphocyte function–associated antigen-1 (LFA-1 and secreted high levels of interleukin (IL-17A. Moreover, DCs obtained during this phase expressed high levels of CD80, CD83, CD86, and intracellular cell adhesion molecule-1 (ICAM-1. Furthermore, we studied the interaction between DCs and γδ T cells by using flow cytometry and confocal microscopy in order to determine whether DCs affected γδ T-cell activation in vitro. Co-cultures of the two types of cells showed that DCs induced high levels of CD69, LFA-1, and IL-17A in γδ T cells. Imaging studies revealed contact between the DCs and γδ T cells. This interaction was mediated by the accumulation of ICAM-1 and LFA-1 at the interface of DCs-γδ T cells. Thus, the activation of γδ T cells in EAU was promoted by DCs interacting with γδ T cells.

Crosstalk between T lymphocytes and dendritic cells.

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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.

Cooperativity of HIV-Specific Cytolytic CD4 T Cells and CD8 T Cells in Control of HIV Viremia

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Johnson, Susan; Eller, Michael; Teigler, Jeffrey E.; Maloveste, Sebastien M.; Schultz, Bruce T.; Soghoian, Damien Z.; Lu, Richard; Oster, Alexander F.; Chenine, Agnès-Laurence; Alter, Galit; Dittmer, Ulf; Marovich, Mary; Robb, Merlin L.; Michael, Nelson L.; Bolton, Diane

2015-01-01

ABSTRACT CD4+ T cells play a pivotal role in the control of chronic viral infections. Recently, nontraditional CD4+ T cell functions beyond helper effects have been described, and a role for cytolytic CD4+ T cells in the control of HIV infection has been suggested. We define here the transcriptional, phenotypic, and functional profiles of HIV-specific cytolytic CD4+ T cells. Fluidigm BioMark and multiparameter flow cytometric analysis of HIV-specific cytolytic CD4+ T cells revealed a distinct transcriptional signature compared to Th1 CD4+ cells but shared similar features with HIV-specific cytolytic CD8+ T cells. Furthermore, HIV-specific cytolytic CD4+ T cells showed comparable killing activity relative to HIV-specific CD8+ T cells and worked cooperatively in the elimination of virally infected cells. Interestingly, we found that cytolytic CD4+ T cells emerge early during acute HIV infection and tightly follow acute viral load trajectory. This emergence was associated to the early viral set point, suggesting an involvement in early control, in spite of CD4 T cell susceptibility to HIV infection. Our data suggest cytolytic CD4+ T cells as an independent subset distinct from Th1 cells that show combined activity with CD8+ T cells in the long-term control of HIV infection. IMPORTANCE The ability of the immune system to control chronic HIV infection is of critical interest to both vaccine design and therapeutic approaches. Much research has focused on the effect of the ability of CD8+ T cells to control the virus, while CD4+ T cells have been overlooked as effectors in HIV control due to the fact that they are preferentially infected. We show here that a subset of HIV-specific CD4+ T cells cooperate in the cytolytic control of HIV replication. Moreover, these cells represent a distinct subset of CD4+ T cells showing significant transcriptional and phenotypic differences compared to HIV-specific Th1 cells but with similarities to CD8+ T cells. These findings are

Mixed Lichenoid and Follicular T- and B-Cell Lymphoid Reaction to Red Tattoos With Monoclonal T Cells.

Science.gov (United States)

Zaaroura, Hiba; Bergman, Reuven

2017-09-28

Pseudolymphomatous reactions have been described to occur in tattoos. Most cases have exhibited T-cell predominance and polyclonal T-cell receptor gene rearrangements. One case with monoclonal IgH gene rearrangements progressed into B-cell lymphoma. Lichenoid infiltrates are commonly described but lymphoid follicles much less frequently. We report a case with mixed lichenoid and follicular T- and B-cell reaction to red tattoos. The histopathology and the immunohistochemical studies were constant with a mixed T- and B-cell pseudolymphoma, the IgH gene rearrangement study was polyclonal, but the T-cell receptor gene rearrangement study was monoclonal. The patient who responded to intralesional corticosteroid injections remains under close scrutiny.

Targeting regulatory T cells in cancer.

LENUS (Irish Health Repository)

Byrne, William L

2012-01-31

Infiltration of tumors by regulatory T cells confers growth and metastatic advantages by inhibiting antitumor immunity and by production of receptor activator of NF-kappaB (RANK) ligand, which may directly stimulate metastatic propagation of RANK-expressing cancer cells. Modulation of regulatory T cells can enhance the efficacy of cancer immunotherapy. Strategies include depletion, interference with function, inhibition of tumoral migration, and exploitation of T-cell plasticity. Problems with these strategies include a lack of specificity, resulting in depletion of antitumor effector T cells or global interruption of regulatory T cells, which may predispose to autoimmune diseases. Emerging technologies, such as RNA interference and tetramer-based targeting, may have the potential to improve selectivity and efficacy.

Regulation of CD8+ T cell responses to retinal antigen by local FoxP3+ regulatory T cells

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Scott W McPherson

2012-06-01

Full Text Available While pathogenic CD4 T cells are well known mediators of autoimmune uveoretinitis, CD8 T cells can also be uveitogenic. Since preliminary studies indicated that C57BL/6 mice were minimally susceptible to autoimmune uveoretinitis induction by CD8 T cells, the basis of the retinal disease resistance was sought. Mice that express β-galactosidase (βgal on a retina-specific promoter (arrβgal mice were backcrossed to mice expressing green fluorescent protein and diphtheria toxin receptor under control of the Foxp3 promoter (Foxp3-DTR/GFP mice, and to T cell receptor transgenic mice that produce βgal specific CD8 T cells (BG1 mice. These mice were used to explore the role of regulatory T cells in the resistance to retinal autoimmune disease. Experiments with T cells from double transgenic BG1 x Foxp3-DTR/GFP mice transferred into Foxp3-DTR/GFP x arrβgal mice confirmed that the retina was well protected from attempts to induce disease by adoptive transfer of activated BG1 T cells. The successful induction of retinal disease following unilateral intraocular administration of diphtheria toxin to deplete regulatory T cells showed that the protective activity was dependent on local, toxin-sensitive regulatory T cells; the opposite, untreated eye remained disease-free. Although there were very few Foxp3+ regulatory T cells in the parenchyma of quiescent retina, and they did not accumulate in retina, their depletion by local toxin administration led to disease susceptibility. We propose that these regulatory T cells modulate the pathogenic activity of βgal-specific CD8 T cells in the retinas of arrβgal mice on a local basis, allowing immunoregulation to be responsive to local conditions.

T cell motility as modulator of interactions with dendritic cells

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Jens Volker Stein

2015-11-01

Full Text Available It is well established that the balance of costimulatory and inhibitory signals during interactions with dendritic cells (DCs determines T cell transition from a naïve to an activated or tolerant/anergic status. While many of these molecular interactions are well reproduced in reductionist in vitro assays, the highly dynamic motility of naïve T cells in lymphoid tissue acts as an additional lever to fine-tune their activation threshold. T cell detachment from DCs providing suboptimal stimulation allows them to search for DCs with higher levels of stimulatory signals, while storing a transient memory of short encounters. In turn, adhesion of weakly reactive T cells to DCs presenting pMHC with low affinity is prevented by lipid mediators. Finally, controlled recruitment of CD8+ T cells to cognate DC – CD4+ T cell clusters shapes memory T cell formation and the quality of the immune response. Dynamic physiological lymphocyte motility therefore constitutes a mechanism to mitigate low avidity T cell activation and to improve the search for optimal DCs, while contributing to peripheral tolerance induction in the absence of inflammation.

Functional analysis of the CC chemokine receptor 5 (CCR5) on virus-specific CD8+ T cells following coronavirus infection of the central nervous system

International Nuclear Information System (INIS)

Glass, William G.; Lane, Thomas E.

2003-01-01

Intracranial infection of C57BL/6 mice with mouse hepatitis virus (MHV) results in an acute encephalomyelitis followed by a demyelinating disease similar in pathology to the human disease multiple sclerosis (MS). T cells participate in both defense and disease progression following MHV infection. Expression of chemokine receptors on activated T cells is important in allowing these cells to traffic into and accumulate within the central nervous system (CNS) of MHV-infected mice. The present study evaluated the contributions of CCR5 to the activation and trafficking of virus-specific CD8 + T cells into the MHV-infected CNS mice. Comparable numbers of virus-specific CD8 + T cells derived from immunized CCR5 +/+ or CCR5 -/- mice were present within the CNS of MHV-infected RAG1 -/- mice following adoptive transfer, indicating that CCR5 is not required for trafficking of these cells into the CNS. RAG1 -/- recipients of CCR5 -/- -derived CD8 + T cells exhibited a modest, yet significant (P ≤ 0.05), reduction in viral burden within the brain which correlated with increased CTL activity and IFN-γ expression. Histological analysis of RAG1 -/- recipients of either CCR5 +/+ or CCR5 -/- -derived CD8 + T cells revealed only focal areas of demyelination with no significant differences in white matter destruction. These data indicate that CCR5 signaling on CD8 + T cells modulates antiviral activities but is not essential for entry into the CNS

TCR down-regulation controls T cell homeostasis

DEFF Research Database (Denmark)

Boding, Lasse; Bonefeld, Charlotte Menné; Nielsen, Bodil L

2009-01-01

TCR and cytokine receptor signaling play key roles in the complex homeostatic mechanisms that maintain a relative stable number of T cells throughout life. Despite the homeostatic mechanisms, a slow decline in naive T cells is typically observed with age. The CD3gamma di-leucine-based motif...... controls TCR down-regulation and plays a central role in fine-tuning TCR expression and signaling in T cells. In this study, we show that the age-associated decline of naive T cells is strongly accelerated in CD3gammaLLAA knock-in mice homozygous for a double leucine to alanine mutation in the CD3gamma di......-leucine-based motif, whereas the number of memory T cells is unaffected by the mutation. This results in premature T cell population senescence with a severe dominance of memory T cells and very few naive T cells in middle-aged to old CD3gamma mutant mice. The reduced number of naive T cells in CD3gamma mutant mice...

Ultrastructural findings in Hashimoto's thyroiditis and focal lymphocytic thyroiditis with reference to giant cell formation.

Science.gov (United States)

Knecht, H; Hedinger, C E

1982-09-01

Ultrastructural findings in two cases of Hashimoto's disease and two cases of focal lymphocytic thyroiditis are reported. Stimulated thyrocytes, oncocytes and degenerating thyrocytes were observed in all cases. Multinucleated thyrocytes and epithelial pseudogiant cells were identified in Hashimoto's disease only. Infiltrating lymphocytes, plasma cells, monocytes and macrophages were present in all cases. The ultrastructure of germinal centres was similar to that seen in lymphatic organs. Giant cells of both intra- and extrafollicular localization were seen in Hashimoto's disease. Most of the giant cells were macrophage-derived. Two different ways of giant cell formation were identified: besides the familiar dissolution of plasma membranes of adjacent macrophages, another mechanism of fusion was observed. At sites of contact, peculiar membrane structures were developed and disintegration of plasma membranes occurred in parts adjacent to these structures. These are not identical to desmosomes and are different from Langerhans' granules. They probably represent special organelles for the initiation of cellular fusion.

CAR-T cells are serial killers.

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Davenport, Alexander J; Jenkins, Misty R; Ritchie, David S; Prince, H Miles; Trapani, Joseph A; Kershaw, Michael H; Darcy, Phillip K; Neeson, Paul J

2015-12-01

Chimeric antigen receptor (CAR) T cells have enjoyed unprecedented clinical success against haematological malignancies in recent years. However, several aspects of CAR T cell biology remain unknown. We recently compared CAR and T cell receptor (TCR)-based killing in the same effector cell and showed that CAR T cells can not only efficiently kill single tumor targets, they can also kill multiple tumor targets in a sequential manner. Single and serial killing events were not sustained long term due to CAR down-regulation after 20 hours.

Common histological patterns in glomerular epithelial cells in secondary focal segmental glomerulosclerosis.

Science.gov (United States)

Kuppe, Christoph; Gröne, Hermann-Josef; Ostendorf, Tammo; van Kuppevelt, Toin H; Boor, Peter; Floege, Jürgen; Smeets, Bart; Moeller, Marcus J

2015-11-01

Parietal epithelial cells (PECs) are involved in the development of sclerotic lesions in primary focal and segmental glomerulosclerosis (FSGS). Here, the role of PECs was explored in the more common secondary FSGS lesions in 68 patient biopsies, diagnosed with 11 different frequently or rarely encountered glomerular pathologies and additional secondary FSGS lesions. For each biopsy, one section was quadruple stained for PECs (ANXA3), podocytes (synaptopodin), PEC matrix (LKIV69), and Hoechst (nuclei), and a second was quadruple stained for activated PECs (CD44 and cytokeratin-19), PEC matrix, and nuclei. In all lesions, cellular adhesions (synechiae) between Bowman's capsule and the tuft were formed by cells expressing podocyte and/or PEC markers. Cells expressing PEC markers were detected in all FSGS lesions independent of the underlying glomerular disease and often stained positive for markers of activation. Small FSGS lesions, which were hardly identified on PAS sections previously, were detectable by immunofluorescent staining using PEC markers, potentially improving the diagnostic sensitivity to identify these lesions. Thus, similar patterns of cells expressing podocyte and/or PEC markers were found in the formation of secondary FSGS lesions independent of the underlying glomerular disease. Hence, our findings support the hypothesis that FSGS lesions follow a final cellular pathway to nephron loss that includes involvement of cells expressing PEC markers.

Spinal focal lesion detection in multiple myeloma using multimodal image features

Science.gov (United States)

Fränzle, Andrea; Hillengass, Jens; Bendl, Rolf

2015-03-01

Multiple myeloma is a tumor disease in the bone marrow that affects the skeleton systemically, i.e. multiple lesions can occur in different sites in the skeleton. To quantify overall tumor mass for determining degree of disease and for analysis of therapy response, volumetry of all lesions is needed. Since the large amount of lesions in one patient impedes manual segmentation of all lesions, quantification of overall tumor volume is not possible until now. Therefore development of automatic lesion detection and segmentation methods is necessary. Since focal tumors in multiple myeloma show different characteristics in different modalities (changes in bone structure in CT images, hypointensity in T1 weighted MR images and hyperintensity in T2 weighted MR images), multimodal image analysis is necessary for the detection of focal tumors. In this paper a pattern recognition approach is presented that identifies focal lesions in lumbar vertebrae based on features from T1 and T2 weighted MR images. Image voxels within bone are classified using random forests based on plain intensities and intensity value derived features (maximum, minimum, mean, median) in a 5 x 5 neighborhood around a voxel from both T1 and T2 weighted MR images. A test data sample of lesions in 8 lumbar vertebrae from 4 multiple myeloma patients can be classified at an accuracy of 95% (using a leave-one-patient-out test). The approach provides a reasonable delineation of the example lesions. This is an important step towards automatic tumor volume quantification in multiple myeloma.

The effect of conditional EFNB1 deletion in the T cell compartment on T cell development and function

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Jin Wei

2011-12-01

Full Text Available Abstract Background Eph kinases are the largest family of cell surface receptor tyrosine kinases. The ligands of Ephs, ephrins (EFNs, are also cell surface molecules. Ephs interact with EFNs transmitting signals in both directions, i.e., from Ephs to EFNs and from EFNs to Ephs. EFNB1 is known to be able to co-stimulate T cells in vitro and to modulate thymocyte development in a model of foetal thymus organ culture. To further understand the role of EFNB1 in T cell immunity, we generated T-cell-specific EFNB1 gene knockout mice to assess T cell development and function in these mice. Results The mice were of normal size and cellularity in the thymus and spleen and had normal T cell subpopulations in these organs. The bone marrow progenitors from KO mice and WT control mice repopulated host spleen T cell pool to similar extents. The activation and proliferation of KO T cells was comparable to that of control mice. Naïve KO CD4 cells showed an ability to differentiate into Th1, Th2, Th17 and Treg cells similar to control CD4 cells. Conclusions Our results suggest that the function of EFNB1 in the T cell compartment could be compensated by other members of the EFN family, and that such redundancy safeguards the pivotal roles of EFNB1 in T cell development and function.

Changes in T-cell subsets after radiation therapy

International Nuclear Information System (INIS)

Yang, S.J.; Rafla, S.; Youssef, E.; Selim, H.; Salloum, N.; Chuang, J.Y.

1988-01-01

The T-cell subsets of 129 patients with cancer were counted before and after radiation therapy. The cells were labeled with monoclonal antibodies that were specific for each type of T cell. Significant changes after therapy were decreases in the proportion of T-helper/inducer cells, pan-T cells, and in the ratio of T-helper/inducer to T-suppressor/cytotoxic cells. There was an increase in the percentage of T-suppressor/cytotoxic cells. When the site of the primary cancer was considered, genitourinary cancer and cancer of the head and neck both showed a decreased percentage of T-helper/inducer cells and a reduced ratio of T-helper/inducer to T-suppressor/cytotoxic cells. The percentage of pan-T cells in head and neck cancer and the ratio of T-helper/inducer to T-suppressor/cytotoxic cells in breast cancer were decreased. The percentage of T-helper cells was particularly decreased by radiation therapy in advanced stages of cancer, in higher grade tumors, and in larger tumors. The absolute numbers of various T-cell subsets were decreased in all groups

Transfer of mRNA Encoding Invariant NKT Cell Receptors Imparts Glycolipid Specific Responses to T Cells and γδT Cells.

Science.gov (United States)

Shimizu, Kanako; Shinga, Jun; Yamasaki, Satoru; Kawamura, Masami; Dörrie, Jan; Schaft, Niels; Sato, Yusuke; Iyoda, Tomonori; Fujii, Shin-Ichiro

2015-01-01

Cell-based therapies using genetically engineered lymphocytes expressing antigen-specific T cell receptors (TCRs) hold promise for the treatment of several types of cancers. Almost all studies using this modality have focused on transfer of TCR from CD8 cytotoxic T lymphocytes (CTLs). The transfer of TCR from innate lymphocytes to other lymphocytes has not been studied. In the current study, innate and adaptive lymphocytes were transfected with the human NKT cell-derived TCRα and β chain mRNA (the Vα24 and Vβ11 TCR chains). When primary T cells transfected with NKT cell-derived TCR were subsequently stimulated with the NKT ligand, α-galactosylceramide (α-GalCer), they secreted IFN-γ in a ligand-specific manner. Furthermore when γδT cells were transfected with NKT cell-derived TCR mRNA, they demonstrated enhanced proliferation, IFN-γ production and antitumor effects after α-GalCer stimulation as compared to parental γδT cells. Importantly, NKT cell TCR-transfected γδT cells responded to both NKT cell and γδT cell ligands, rendering them bi-potential innate lymphocytes. Because NKT cell receptors are unique and universal invariant receptors in humans, the TCR chains do not yield mispaired receptors with endogenous TCR α and β chains after the transfection. The transfection of NKT cell TCR has the potential to be a new approach to tumor immunotherapy in patients with various types of cancer.

CAR T cell therapy for breast cancer: harnessing the tumor milieu to drive T cell activation.

Science.gov (United States)

Bajgain, Pradip; Tawinwung, Supannikar; D'Elia, Lindsey; Sukumaran, Sujita; Watanabe, Norihiro; Hoyos, Valentina; Lulla, Premal; Brenner, Malcolm K; Leen, Ann M; Vera, Juan F

2018-05-10

The adoptive transfer of T cells redirected to tumor via chimeric antigen receptors (CARs) has produced clinical benefits for the treatment of hematologic diseases. To extend this approach to breast cancer, we generated CAR T cells directed against mucin1 (MUC1), an aberrantly glycosylated neoantigen that is overexpressed by malignant cells and whose expression has been correlated with poor prognosis. Furthermore, to protect our tumor-targeted cells from the elevated levels of immune-inhibitory cytokines present in the tumor milieu, we co-expressed an inverted cytokine receptor linking the IL4 receptor exodomain with the IL7 receptor endodomain (4/7ICR) in order to transform the suppressive IL4 signal into one that would enhance the anti-tumor effects of our CAR T cells at the tumor site. First (1G - CD3ζ) and second generation (2G - 41BB.CD3ζ) MUC1-specific CARs were constructed using the HMFG2 scFv. Following retroviral transduction transgenic expression of the CAR±ICR was assessed by flow cytometry. In vitro CAR/ICR T cell function was measured by assessing cell proliferation and short- and long-term cytotoxic activity using MUC1+ MDA MB 468 cells as targets. In vivo anti-tumor activity was assessed using IL4-producing MDA MB 468 tumor-bearing mice using calipers to assess tumor volume and bioluminescence imaging to track T cells. In the IL4-rich tumor milieu, 1G CAR.MUC1 T cells failed to expand or kill MUC1+ tumors and while co-expression of the 4/7ICR promoted T cell expansion, in the absence of co-stimulatory signals the outgrowing cells exhibited an exhausted phenotype characterized by PD-1 and TIM3 upregulation and failed to control tumor growth. However, by co-expressing 2G CAR.MUC1 (signal 1 - activation + signal 2 - co-stimulation) and 4/7ICR (signal 3 - cytokine), transgenic T cells selectively expanded at the tumor site and produced potent and durable tumor control in vitro and in vivo. Our findings demonstrate the feasibility of targeting breast

T cell dysfunction in the diabetes-prone BB rat. A role for thymic migrants that are not T cell precursors

International Nuclear Information System (INIS)

Georgiou, H.M.; Lagarde, A.C.; Bellgrau, D.

1988-01-01

Diabetes-prone BB (BB-DP) rats express several T cell dysfunctions which include poor proliferative and cytotoxic responses to alloantigen. The goal of this study was to determine the origin of these T cell dysfunctions. When BB-DP rats were thymectomized, T cell depleted, and transplanted with neonatal thymus tissue from diabetes-resistant and otherwise normal DA/BB F1 rats, the early restoration of T cell function proceeded normally on a cell-for-cell basis; i.e., peripheral T cells functioned like those from the thymus donor. Because the thymus in these experiments was subjected to gamma irradiation before transplantation and there was no evidence of F1 chimerism in the transplanted BB-DP rats, it appeared that the BB-DP T cell precursors could mature into normally functioning T cells if the maturation process occurred in a normal thymus. If the F1 thymus tissue was treated with dGua before transplantation, the T cells of these animals functioned poorly like those from untreated BB-DP rats. dGua poisons bone marrow-derived cells, including gamma radiation-resistant cells of the macrophage/dendritic cell lineages, while sparing the thymic epithelium. Therefore, the reversal of the T cell dysfunction depends on the presence in the F1 thymus of gamma radiation-resistant, dGua-sensitive F1 cells. Conversely, thymectomized and T cell-depleted F1 rats expressed T cell dysfunction when transplanted with gamma-irradiated BB thymus grafts. T cell responses were normal in animals transplanted with dGua-treated BB thymus grafts. With increasing time after thymus transplantation, T cells from all animals gradually expressed the functional phenotype of the bone marrow donor. Taken together these results suggest that BB-DP bone marrow-derived cells that are not T cell precursors influence the maturation environment in the thymus of otherwise normal BB-DP T cell precursors

The Effect of Artificial Aging on the Tensile Properties of Alclad 24S-T and 24S-T Aluminum Alloy

Science.gov (United States)

Kotanchik, Joseph N.; Woods, Walter; Zender, George W.

1943-01-01

An experimental study was made to determine the effect of artificial aging on the tensile properties of alclad 24S-T and 24S-T aluminum-alloy sheet material. The results of the tests show that certain combinations of aging time and temperature cause a marked increase in the yield strength and a small increase in the ultimate strength; these increases are accompanied by a very large decrease in elongation. A curve is presented that shows the maximum yield strengths that can be obtained by aging this material at various combinations of time and temperature. The higher values of yield stress are obtained in material aged at relatively longer times and lower temperatures.

The role of natural killer T cells in dendritic cell licensing, cross-priming and memory CD8+ T cell generation

Directory of Open Access Journals (Sweden)

Catherine eGottschalk

2015-07-01

Full Text Available New vaccination strategies focus on achieving CD8+ T cell (CTL immunity rather than on induction of protective antibody responses. While the requirement of CD4+ T (Th cell help in dendritic cell (DC activation and licensing, and in CTL memory induction has been described in several disease models, CTL responses may occur in a Th cell help independent manner. Natural Killer T cells (NKT cells can substitute for Th cell help and license DC as well. NKT cells produce a broad spectrum of Th1 and Th2 cytokines, thereby inducing a similar set of costimulatory molecules and cytokines in DC. This form of licensing differs from Th cell help by inducing other chemokines: while Th cell licensed DC produce CCR5 ligands, NKT cell-licensed DC produce CCL17 which attracts CCR4+ CD8+ T cells for subsequent activation. It has recently been shown that iNKT cells do not only enhance immune responses against bacterial pathogens or parasites, but also play a role in viral infections. The inclusion of NKT cell ligands in Influenza virus vaccines enhanced memory CTL generation and protective immunity in a mouse model. This review will focus on the role of iNKT cells in the cross-talk with cross-priming DC and memory CD8+ T cell formation.

How to train your T cell: genetically engineered chimeric antigen receptor T cells versus bispecific T-cell engagers to target CD19 in B acute lymphoblastic leukemia.

Science.gov (United States)

Ruella, Marco; Gill, Saar

2015-06-01

Antigen-specific T cell-based immunotherapy is getting its day in the sun. The contemporaneous development of two potent CD19-specific immunotherapeutic modalities for the treatment of B-cell malignancies provides exciting opportunities for patients, physicians and scientists alike. Patients with relapsed, refractory or poor-risk B-cell acute lymphoblastic leukemia (ALL) previously had few therapeutic options and now have two potential new lifelines. Physicians will have the choice between two powerful modalities and indeed could potentially enroll some patients on trials exploring both modalities if needed. For scientists interested in tumor immunology, the advent of chimeric antigen receptor T-cell therapy and of bispecific T-cell engagers (BiTEs) provides unprecedented opportunities to explore the promise and limitations of antigen-specific T-cell therapy in the context of human leukemia. In this article, we compare chimeric antigen receptor T cells and BiTEs targeting CD19 in B-cell ALL in the setting of the available clinical literature.

Immunological aspects of adult T-cell leukemia/lymphoma (ATLL), a possible neoplasm of regulatory T-cells

OpenAIRE

Yamada, Yasuaki; Kamihira, Shimeru

2008-01-01

Adult T-cell leukemia/lymphoma (ATLL) is a distinct disease caused by the first discovered human oncogenic retrovirus, human T-cell leukemia virus type-1 (HTLV-1). The peculiarity of this disease is not only in its causative agent HTLV-1 but also in the character of leukemia cells. ATLL cells express the mature helper/inducer T-cell antigens, CD2, CD3, CD4 and CD5 but usually lacking CD8. Despite CD4 expression, it has long been known that ATLL cells exhibit strong immunosuppressive activity ...

Regulatory T Cells Contribute to the Inhibition of Radiation-Induced Acute Lung Inflammation via Bee Venom Phospholipase A₂ in Mice.

Science.gov (United States)

Shin, Dasom; Lee, Gihyun; Sohn, Sung-Hwa; Park, Soojin; Jung, Kyung-Hwa; Lee, Ji Min; Yang, Jieun; Cho, Jaeho; Bae, Hyunsu

2016-04-30

Bee venom has long been used to treat various inflammatory diseases, such as rheumatoid arthritis and multiple sclerosis. Previously, we reported that bee venom phospholipase A₂ (bvPLA₂) has an anti-inflammatory effect through the induction of regulatory T cells. Radiotherapy is a common anti-cancer method, but often causes adverse effects, such as inflammation. This study was conducted to evaluate the protective effects of bvPLA₂ in radiation-induced acute lung inflammation. Mice were focally irradiated with 75 Gy of X-rays in the lung and administered bvPLA₂ six times after radiation. To evaluate the level of inflammation, the number of immune cells, mRNA level of inflammatory cytokine, and histological changes in the lung were measured. BvPLA₂ treatment reduced the accumulation of immune cells, such as macrophages, neutrophils, lymphocytes, and eosinophils. In addition, bvPLA₂ treatment decreased inflammasome-, chemokine-, cytokine- and fibrosis-related genes' mRNA expression. The histological results also demonstrated the attenuating effect of bvPLA₂ on radiation-induced lung inflammation. Furthermore, regulatory T cell depletion abolished the therapeutic effects of bvPLA₂ in radiation-induced pneumonitis, implicating the anti-inflammatory effects of bvPLA₂ are dependent upon regulatory T cells. These results support the therapeutic potential of bvPLA₂ in radiation pneumonitis and fibrosis treatments.

Suppression of pro-inflammatory T-cell responses by human mesothelial cells.

Science.gov (United States)

Lin, Chan-Yu; Kift-Morgan, Ann; Moser, Bernhard; Topley, Nicholas; Eberl, Matthias

2013-07-01

Human γδ T cells reactive to the microbial metabolite (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMB-PP) contribute to acute inflammatory responses. We have previously shown that peritoneal dialysis (PD)-associated infections with HMB-PP producing bacteria are characterized by locally elevated γδ T-cell frequencies and poorer clinical outcome compared with HMB-PP negative infections, implying that γδ T cells may be of diagnostic, prognostic and therapeutic value in acute disease. The regulation by local tissue cells of these potentially detrimental γδ T-cell responses remains to be investigated. Freshly isolated γδ or αβ T cells were cultured with primary mesothelial cells derived from omental tissue, or with mesothelial cell-conditioned medium. Stimulation of cytokine production and proliferation by peripheral T cells in response to HMB-PP or CD3/CD28 beads was assessed by flow cytometry. Resting mesothelial cells were potent suppressors of pro-inflammatory γδ T cells as well as CD4+ and CD8+ αβ T cells. The suppression of γδ T-cell responses was mediated through soluble factors released by primary mesothelial cells and could be counteracted by SB-431542, a selective inhibitor of TGF-β and activin signalling. Recombinant TGF-β1 but not activin-A mimicked the mesothelial cell-mediated suppression of γδ T-cell responses to HMB-PP. The present findings indicate an important regulatory function of mesothelial cells in the peritoneal cavity by dampening pro-inflammatory T-cell responses, which may help preserve the tissue integrity of the peritoneal membrane in the steady state and possibly during the resolution of acute inflammation.

Role of T-bet, the master regulator of Th1 cells, in the cytotoxicity of murine CD4+ T cells.

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Eshima, Koji; Misawa, Kana; Ohashi, Chihiro; Iwabuchi, Kazuya

2018-05-01

Although CD4 + T cells are generally regarded as helper T cells, some activated CD4 + T cells have cytotoxic properties. Given that CD4 + cytotoxic T lymphocytes (CTLs) often secrete IFN-γ, CTL activity among CD4 + T cells may be attributable to Th1 cells, where a T-box family molecule, T-bet serves as the "master regulator". However, although the essential contribution of T-bet to expression of IFN-γ has been well-documented, it remains unclear whether T-bet is involved in CD4 + T cell-mediated cytotoxicity. In this study, to investigate the ability of T-bet to confer cytolytic activity on CD4 + T cells, the T-bet gene (Tbx21) was introduced into non-cytocidal CD4 + T cell lines and their cytolytic function analyzed. Up-regulation of FasL (CD178), which provided the transfectant with cytotoxicity, was observed in Tbx21transfected CD4 + T cells but not in untransfected parental cells. In one cell line, T-bet transduction also induced perforin gene (Prf1) expression and Tbx21 transfectants efficiently killed Fas - target cells. Although T-bet was found to repress up-regulation of CD40L (CD154), which controls FasL-mediated cytolysis, the extent of CD40L up-regulation on in vitro-differentiated Th1 cells was similar to that on Th2 cells, suggesting the existence of a compensatory mechanism. These results collectively indicate that T-bet may be involved in the expression of genes, such as FasL and Prf1, which confer cytotoxicity on Th1 cells. © 2018 The Societies and John Wiley & Sons Australia, Ltd.

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.