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Sample records for peripheral b-cell compartment

  1. Human herpesvirus-8 infection leads to expansion of the preimmune/natural effector B cell compartment.

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    Silvia Della Bella

    Full Text Available BACKGROUND: Human herpesvirus-8 (HHV-8 is the etiological agent of Kaposi's sarcoma (KS and of some lymphoproliferative disorders of B cells. Most malignancies develop after long-lasting viral dormancy, and a preventing role for both humoral and cellular immune control is suggested by the high frequency of these pathologies in immunosuppressed patients. B cells, macrophages and dendritic cells of peripheral lymphoid organs and blood represent the major reservoir of HHV-8. Due to the dual role of B cells in HHV-8 infection, both as virus reservoir and as agents of humoral immune control, we analyzed the subset distribution and the functional state of peripheral blood B cells in HHV-8-infected individuals with and without cKS. METHODOLOGY/PRINCIPAL FINDINGS: Circulating B cells and their subsets were analyzed by 6-color flow cytometry in the following groups: 1- patients HHV-8 positive with classic KS (cKS (n = 47; 2- subjects HHV-8 positive and cKS negative (HSP (n = 10; 3- healthy controls, HHV-8 negative and cKS negative (HC (n = 43. The number of B cells belonging to the preimmune/natural effector compartment, including transitional, pre-naïve, naïve and MZ-like subsets, was significantly higher among HHV-8 positive subjects, with or without cKS, while was comparable to healthy controls in the antigen-experienced T-cell dependent compartment. The increased number of preimmune/natural effector B cells was associated with increased resistance to spontaneous apoptosis, while it did not correlate with HHV-8 viral load. CONCLUSIONS/SIGNIFICANCE: Our results indicate that long-lasting HHV-8 infection promotes an imbalance in peripheral B cell subsets, perturbing the equilibrium between earlier and later steps of maturation and activation processes. This observation may broaden our understanding of the complex interplay between viral and immune factors leading HHV-8-infected individuals to develop HHV-8-associated malignancies.

  2. Engaging the lysosomal compartment to combat B cell malignancies

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    Gronbaek, K.; Jaattela, M.

    2009-01-01

    The combination of rituximab, a type I anti-CD20 mAb, with conventional chemotherapy has significantly improved the outcome of patients with B cell malignancies. Regardless of this success, many patients still relapse with therapy-resistant disease, highlighting the need for the development of m...

  3. Invasin of Yersinia pseudotuberculosis activates human peripheral B cells.

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    Lundgren, E; Carballeira, N; Vazquez, R; Dubinina, E; Bränden, H; Persson, H; Wolf-Watz, H

    1996-01-01

    The Yersinia pseudotuberculosis cell surface-located protein invasin was found to promote binding between the pathogen and resting peripheral B cells via beta 1 integrin receptors (CD29). B cells responded by expressing several activation markers and by growing, In contrast, T cells did not react, although these cells express CD29. An isogenic invA mutant failed to activate B cells. The mutation could be complemented by providing the invA+ gene in trans. Purified invasin alone did not activat...

  4. Deficiency in memory B cell compartment in a patient with infertility and recurrent pregnancy losses.

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    Sung, N; Byeon, H J; Garcia, M D Salazar; Skariah, A; Wu, L; Dambaeva, S; Beaman, K; Gilman-Sachs, A; Kwak-Kim, J

    2016-11-01

    Alterations in normal balance of B cell subsets have been reported in various rheumatic diseases. In this study, we report a woman with a history of recurrent pregnancy losses (RPL) and infertility who had low levels of memory B cells. A 35-year-old woman with a history of RPL and infertility was demonstrated to have increased peripheral blood CD19+ B cells with persistently low levels of memory B cell subsets. Prior to the frozen donor egg transfer cycle, prednisone and intravenous immunoglobulin G (IVIg) treatment was initiated and patient achieved dichorionic diamniotic twin pregnancies. During pregnancy, proportion (%) of switched memory B cells CD27+IgD- increased, while percent of total CD19+ B cells and CD27-IgD+ naive B cells were gradually decreased with a high dose IVIg treatment. She developed cervical incompetence at 20 weeks of gestation, received a Cesarean section at 32 weeks of gestation due to preterm labor, and delivered twin babies. B cell subset abnormalities may be associated with infertility, RPL and preterm labor, and further investigation is needed. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  5. Altered distribution of peripheral blood memory B cells in humans chronically infected with Trypanosoma cruzi.

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    Fernández, Esteban R; Olivera, Gabriela C; Quebrada Palacio, Luz P; González, Mariela N; Hernandez-Vasquez, Yolanda; Sirena, Natalia María; Morán, María L; Ledesma Patiño, Oscar S; Postan, Miriam

    2014-01-01

    Numerous abnormalities of the peripheral blood T cell compartment have been reported in human chronic Trypanosoma cruzi infection and related to prolonged antigenic stimulation by persisting parasites. Herein, we measured circulating lymphocytes of various phenotypes based on the differential expression of CD19, CD4, CD27, CD10, IgD, IgM, IgG and CD138 in a total of 48 T. cruzi-infected individuals and 24 healthy controls. Infected individuals had decreased frequencies of CD19+CD27+ cells, which positively correlated with the frequencies of CD4+CD27+ cells. The contraction of CD19+CD27+ cells was comprised of IgG+IgD-, IgM+IgD- and isotype switched IgM-IgD- memory B cells, CD19+CD10+CD27+ B cell precursors and terminally differentiated CD19+CD27+CD138+ plasma cells. Conversely, infected individuals had increased proportions of CD19+IgG+CD27-IgD- memory and CD19+IgM+CD27-IgD+ transitional/naïve B cells. These observations prompted us to assess soluble CD27, a molecule generated by the cleavage of membrane-bound CD27 and used to monitor systemic immune activation. Elevated levels of serum soluble CD27 were observed in infected individuals with Chagas cardiomyopathy, indicating its potentiality as an immunological marker for disease progression in endemic areas. In conclusion, our results demonstrate that chronic T. cruzi infection alters the distribution of various peripheral blood B cell subsets, probably related to the CD4+ T cell deregulation process provoked by the parasite in humans.

  6. Altered distribution of peripheral blood memory B cells in humans chronically infected with Trypanosoma cruzi.

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    Esteban R Fernández

    Full Text Available Numerous abnormalities of the peripheral blood T cell compartment have been reported in human chronic Trypanosoma cruzi infection and related to prolonged antigenic stimulation by persisting parasites. Herein, we measured circulating lymphocytes of various phenotypes based on the differential expression of CD19, CD4, CD27, CD10, IgD, IgM, IgG and CD138 in a total of 48 T. cruzi-infected individuals and 24 healthy controls. Infected individuals had decreased frequencies of CD19+CD27+ cells, which positively correlated with the frequencies of CD4+CD27+ cells. The contraction of CD19+CD27+ cells was comprised of IgG+IgD-, IgM+IgD- and isotype switched IgM-IgD- memory B cells, CD19+CD10+CD27+ B cell precursors and terminally differentiated CD19+CD27+CD138+ plasma cells. Conversely, infected individuals had increased proportions of CD19+IgG+CD27-IgD- memory and CD19+IgM+CD27-IgD+ transitional/naïve B cells. These observations prompted us to assess soluble CD27, a molecule generated by the cleavage of membrane-bound CD27 and used to monitor systemic immune activation. Elevated levels of serum soluble CD27 were observed in infected individuals with Chagas cardiomyopathy, indicating its potentiality as an immunological marker for disease progression in endemic areas. In conclusion, our results demonstrate that chronic T. cruzi infection alters the distribution of various peripheral blood B cell subsets, probably related to the CD4+ T cell deregulation process provoked by the parasite in humans.

  7. Pregnancy alters the circulating B cell compartment in atopic asthmatic women, and transitional B cells are positively associated with the development of allergy manifestations in their progeny.

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    Martins, Catarina; Lima, Jorge; Nunes, Glória; Borrego, Luís Miguel

    2016-12-01

    Maternal atopy is a risk factor for allergy. B cells are poorly studied in reproduction and atopy. We aimed to assess how pregnancy affects B cells in atopic women and whether B cells relate to allergic manifestations in offspring. Women with and without atopic asthma, pregnant and non-pregnant were enrolled for the study, and circulating B cells were evaluated by flow cytometry, using CD19, CD27, CD38, IgD, and IgM. Compared to healthy non-pregnant, atopic asthmatic non-pregnant (ANP) women presented increased B cell counts, enlarged memory subsets, less transitional cells, and plasmablasts. Atopic asthmatic pregnant (AP) and healthy pregnant (HP) women showed similarities: reduced B cell counts and percentages, fewer memory cells, especially switched, and higher plasmablast percentages. Transitional B cell percentages were increased in AP women with allergic manifestations in their progeny. Atopic asthmatic non-pregnant women have a distinctive B cell compartment. B cells change in pregnancy, similarly in AP and HP women. The recognition that AP women with allergy in their progeny have a typical immune profile may help, in the future, the adoption of preventive measures to avoid the manifestation of allergic diseases in their newborns. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Alterations on peripheral B cell subsets following an acute uncomplicated clinical malaria infection in children

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    Ng'ang'a Zipporah W

    2008-11-01

    Full Text Available Abstract Background The effects of Plasmodium falciparum on B-cell homeostasis have not been well characterized. This study investigated whether an episode of acute malaria in young children results in changes in the peripheral B cell phenotype. Methods Using flow-cytofluorimetric analysis, the B cell phenotypes found in the peripheral blood of children aged 2–5 years were characterized during an episode of acute uncomplicated clinical malaria and four weeks post-recovery and in healthy age-matched controls. Results There was a significant decrease in CD19+ B lymphocytes during acute malaria. Characterization of the CD19+ B cell subsets in the peripheral blood based on expression of IgD and CD38 revealed a significant decrease in the numbers of naive 1 CD38-IgD+ B cells while there was an increase in CD38+IgD- memory 3 B cells during acute malaria. Further analysis of the peripheral B cell phenotype also identified an expansion of transitional CD10+CD19+ B cells in children following an episode of acute malaria with up to 25% of total CD19+ B cell pool residing in this subset. Conclusion Children experiencing an episode of acute uncomplicated clinical malaria experienced profound disturbances in B cell homeostasis.

  9. Epigenetics of peripheral B cell differentiation and the antibody response

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    Hong eZan

    2015-12-01

    Full Text Available Epigenetic modifications, such as histone post-translational modifications, DNA methylation, and alteration of gene expression by non-coding RNAs, including microRNAs (miRNAs and long non-coding RNAs (lncRNAs, are heritable changes that are independent from the genomic DNA sequence. These regulate gene activities and, therefore, cellular functions. Epigenetic modifications act in concert with transcription factors and play critical roles in B cell development and differentiation, thereby modulating antibody responses to foreign- and self-antigens. Upon antigen encounter by mature B cells in the periphery, alterations of these lymphocytes epigenetic landscape are induced by the same stimuli that drive the antibody response. Such alterations instruct B cells to undergo immunoglobulin class switch DNA recombination (CSR and somatic hypermutation (SHM, as well as differentiation to memory B cells or long-lived plasma cells for the immune memory. Inducible histone modifications, together with DNA methylation and miRNAs modulate the transcriptome, particularly the expression of activation-induced cytidine deaminase (AID, which is essential for CSR and SHM, and factors central to plasma cell differentiation, such as B lymphocyte-induced maturation protein-1 (Blimp-1. These inducible B cell-intrinsic epigenetic marks guide the maturation of antibody responses. Combinatorial histone modifications also function as histone codes to target CSR and, possibly, SHM machinery to the Ig loci by recruiting specific adaptors that can stabilize CSR/SHM factors. In addition, lncRNAs, such as recently reported lncRNA-CSR and an lncRNA generated through transcription of the S region that form G-quadruplex structures, are also important for CSR targeting. Epigenetic dysregulation in B cells, including the aberrant expression of non-coding RNAs and alterations of histone modifications and DNA methylation, can result in aberrant antibody responses to foreign antigens

  10. PTEN and PI-3 kinase inhibitors control LPS signaling and the lymphoproliferative response in the CD19+ B cell compartment

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    Singh, Alok R.; Peirce, Susan K.; Joshi, Shweta; Durden, Donald L.

    2014-01-01

    Pattern recognition receptors (PRRs), e.g. toll receptors (TLRs) that bind ligands within the microbiome have been implicated in the pathogenesis of cancer. LPS is a ligand for two TLR family members, TLR4 and RP105 which mediate LPS signaling in B cell proliferation and migration. Although LPS/TLR/RP105 signaling is well-studied; our understanding of the underlying molecular mechanisms controlling these PRR signaling pathways remains incomplete. Previous studies have demonstrated a role for PTEN/PI-3K signaling in B cell selection and survival, however a role for PTEN/PI-3K in TLR4/RP105/LPS signaling in the B cell compartment has not been reported. Herein, we crossed a CD19cre and PTEN fl/fl mouse to generate a conditional PTEN knockout mouse in the CD19+ B cell compartment. These mice were further crossed with an IL-14α transgenic mouse to study the combined effect of PTEN deletion, PI-3K inhibition and expression of IL-14α (a cytokine originally identified as a B cell growth factor) in CD19+ B cell lymphoproliferation and response to LPS stimulation. Targeted deletion of PTEN and directed expression of IL-14α in the CD19+ B cell compartment (IL-14+PTEN-/-) lead to marked splenomegaly and altered spleen morphology at baseline due to expansion of marginal zone B cells, a phenotype that was exaggerated by treatment with the B cell mitogen and TLR4/RP105 ligand, LPS. Moreover, LPS stimulation of CD19+ cells isolated from these mice display increased proliferation, augmented AKT and NFκB activation as well as increased expression of c-myc and cyclinD1. Interestingly, treatment of LPS treated IL-14+PTEN-/- mice with a pan PI-3K inhibitor, SF1126, reduced splenomegaly, cell proliferation, c-myc and cyclin D1 expression in the CD19+ B cell compartment and normalized the splenic histopathologic architecture. These findings provide the direct evidence that PTEN and PI-3K inhibitors control TLR4/RP105/LPS signaling in the CD19+ B cell compartment and that pan PI-3

  11. PTEN and PI-3 kinase inhibitors control LPS signaling and the lymphoproliferative response in the CD19+ B cell compartment

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    Singh, Alok R. [UCSD Department of Pediatrics, Moores UCSD Cancer Center, University of California School of Medicine, San Diego, CA 92093 (United States); Peirce, Susan K. [Department of Pediatrics, Emory University School of Medicine, Atlanta, GA (United States); Joshi, Shweta [UCSD Department of Pediatrics, Moores UCSD Cancer Center, University of California School of Medicine, San Diego, CA 92093 (United States); Durden, Donald L., E-mail: ddurden@ucsd.edu [UCSD Department of Pediatrics, Moores UCSD Cancer Center, University of California School of Medicine, San Diego, CA 92093 (United States); Division of Pediatric Hematology-Oncology, UCSD Rady Children' s Hospital, La Jolla, CA (United States)

    2014-09-10

    Pattern recognition receptors (PRRs), e.g. toll receptors (TLRs) that bind ligands within the microbiome have been implicated in the pathogenesis of cancer. LPS is a ligand for two TLR family members, TLR4 and RP105 which mediate LPS signaling in B cell proliferation and migration. Although LPS/TLR/RP105 signaling is well-studied; our understanding of the underlying molecular mechanisms controlling these PRR signaling pathways remains incomplete. Previous studies have demonstrated a role for PTEN/PI-3K signaling in B cell selection and survival, however a role for PTEN/PI-3K in TLR4/RP105/LPS signaling in the B cell compartment has not been reported. Herein, we crossed a CD19cre and PTEN{sup fl/fl} mouse to generate a conditional PTEN knockout mouse in the CD19+ B cell compartment. These mice were further crossed with an IL-14α transgenic mouse to study the combined effect of PTEN deletion, PI-3K inhibition and expression of IL-14α (a cytokine originally identified as a B cell growth factor) in CD19+ B cell lymphoproliferation and response to LPS stimulation. Targeted deletion of PTEN and directed expression of IL-14α in the CD19+ B cell compartment (IL-14+PTEN-/-) lead to marked splenomegaly and altered spleen morphology at baseline due to expansion of marginal zone B cells, a phenotype that was exaggerated by treatment with the B cell mitogen and TLR4/RP105 ligand, LPS. Moreover, LPS stimulation of CD19+ cells isolated from these mice display increased proliferation, augmented AKT and NFκB activation as well as increased expression of c-myc and cyclinD1. Interestingly, treatment of LPS treated IL-14+PTEN-/- mice with a pan PI-3K inhibitor, SF1126, reduced splenomegaly, cell proliferation, c-myc and cyclin D1 expression in the CD19+ B cell compartment and normalized the splenic histopathologic architecture. These findings provide the direct evidence that PTEN and PI-3K inhibitors control TLR4/RP105/LPS signaling in the CD19+ B cell compartment and that pan PI

  12. Analysis of Peripheral B Cell Subsets in Patients With Allergic Rhinitis.

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    Luo, Jing; Guo, Huanhuan; Liu, Zhuofu; Peng, Tao; Hu, Xianting; Han, Miaomiao; Yang, Xiangping; Zhou, Xuhong; Li, Huabin

    2018-05-01

    Recent evidence suggests that B cells can both promote and inhibit the development and progression of allergic disease. However, the characteristics of B cell subsets in patients with allergic rhinitis (AR) have not been well documented. This study aimed to analyze the characteristics of B cell subsets in the peripheral blood of AR patients. Forty-seven AR patients and 54 healthy controls were enrolled in this study, and the B cell subsets in peripheral blood of all subjects were analyzed by flow cytometry. Moreover, the serum total immunoglobulin E (IgE) and IgE concentrations secreted into the cultured peripheral blood mononuclear cells (PBMCs) were measured by using enzyme-linked immunosorbent assay. We found the peripheral blood of AR patients contained higher percentages of memory B cells, plasma cells, and CD19⁺CD24(hi)CD27⁺ regulatory B cells (Bregs) than those of age-matched healthy controls (PB cells and CD19⁺CD24(hi)CD38(hi) Bregs were significantly lower in AR patients than in healthy individuals (PB cells or plasma cells and decreases in CD19⁺CD24(hi)CD38(hi) Breg cells in the peripheral blood. Copyright © 2018 The Korean Academy of Asthma, Allergy and Clinical Immunology · The Korean Academy of Pediatric Allergy and Respiratory Disease.

  13. Identification of early B cell precursors (stage 1 and 2 hematogones) in the peripheral blood.

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    Kurzer, Jason H; Weinberg, Olga K

    2018-05-25

    Differentiating malignant B-lymphoblasts from early benign B cell precursors (hematogones) is a vital component of the diagnosis of B-lymphoblastic leukaemia. It has been previously reported that only late-stage B cell precursors circulate in the peripheral blood. Consequently, flow cytometric detection of cells with immunophenotypic findings similar to earlier stage precursors in the peripheral blood justifiably raises concern for involvement by B-lymphoblastic leukaemia. We report here, however, that benign early B cell precursors can indeed be detected in the peripheral blood, thus complicating the interpretation of flow cytometric findings derived from these sample types. A retrospective search of our collective databases identified 13 cases containing circulating early stage B cell precursors. The patients ranged in age from 15 days to 85 years old. All positive cases demonstrated that the earlier B cell precursors were associated with later stage precursors, a finding that could help differentiate these cells from B-lymphoblastic leukaemia. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  14. Long-term safety of rituximab induced peripheral B-cell depletion in autoimmune neurological diseases.

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    Anza B Memon

    Full Text Available B-cells play a pivotal role in several autoimmune diseases, including patients with immune-mediated neurological disorders (PIMND, such as neuromyelitis optica (NMO, multiple sclerosis (MS, and myasthenia gravis (MG. Targeting B-cells has been an effective approach in ameliorating both central and peripheral autoimmune diseases. However, there is a paucity of literature on the safety of continuous B-cell depletion over a long period of time.The aim of this study was to examine the long-term safety, incidence of infections, and malignancies in subjects receiving continuous therapy with a B-cell depleting agent rituximab over at least 3 years or longer.This was a retrospective study involving PIMND who received continuous cycles of rituximab infusions every 6 to 9 months for up to 7 years. The incidence of infection related adverse events (AE, serious adverse events (SAE, and malignancies were observed.There were a total of 32 AE and 4 SAE with rituximab treatment. The 3 SAE were noted after 9 cycles (48 months and 1 SAE was observed after 11 cycles (60 months of rituximab. There were no cases of Progressive multifocal leukoencephalopathy (PML and malignancies observed throughout the treatment period. Rituximab was well tolerated without any serious infusion reactions. Also, rituximab was found to be beneficial in treating PIMND over a 7-year period.This study demonstrates that long-term depletion of peripheral B-cells appears safe and efficacious in treating PIMND. Longer and larger prospective studies with rituximab are needed to carefully ascertain risks associated with chronic B-cell depletion, including malignancies. Recognizing that this is a small, retrospective study, such data nonetheless complement the growing literature documenting the safety and tolerability of B-cell depleting agents in neurological diseases.

  15. Altered Distribution of Peripheral Blood Maturation-Associated B-Cell Subsets in Chronic Alcoholism.

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    Almeida, Julia; Polvorosa, Maria Angeles; Gonzalez-Quintela, Arturo; Madruga, Ignacio; Marcos, Miguel; Pérez-Nieto, Maria Angeles; Hernandez-Cerceño, Maria Luisa; Orfao, Alberto; Laso, Francisco Javier

    2015-08-01

    Although decreased counts of peripheral blood (PB) B cells-associated with an apparently contradictory polyclonal hypergammaglobulinemia-have been reported in chronic alcoholism, no information exists about the specific subsets of circulating B cells altered and their relationship with antibody production. Here, we analyzed for the first time the distribution of multiple maturation-associated subpopulations of PB B cells in alcoholism and its potential relationship with the onset of liver disease. PB samples from 35 male patients-20 had alcoholic hepatitis (AH) and 15 chronic alcoholism without liver disease (AWLD)-were studied, in parallel to 19 male healthy donors (controls). The distribution of PB B-cell subsets (immature/regulatory, naïve, CD27(-) and CD27(+) memory B lymphocytes, and circulating plasmablasts of distinct immunoglobulin-Ig-isotypes) was analyzed by flow cytometry. Patients with AH showed significantly decreased numbers of total PB B lymphocytes (vs. controls and AWLD), at the expense of immature, memory, and, to a lesser extent, also naïve B cells. AWLD showed reduced numbers of immature and naïve B cells (vs. controls), but higher PB counts of plasmablasts (vs. the other 2 groups). Although PB memory B cells were reduced among the patients, the percentage of surface (s)IgA(+) cells (particularly CD27(-) /sIgA(+) cells) was increased in AH, whereas both sIgG(+) and sIgA(+) memory B cells were significantly overrepresented in AWLD versus healthy donors. Regarding circulating plasmablasts, patients with AH only showed significantly reduced counts of sIgG(+) cells versus controls. In contrast, the proportion of both sIgA(+) and sIgG(+) plasmablasts-from all plasmablasts-was reduced in AH and increased in AWLD (vs. the other 2 groups). AH and AWLD patients display a significantly reduced PB B-cell count, at the expense of decreased numbers of recently produced immature/regulatory B cells and naïve B cells, together with an increase in Ig

  16. Pediatric Solid-Organ Transplant Recipients Carry Chronic Loads of Epstein-Barr Virus Exclusively in the Immunoglobulin D-Negative B-Cell Compartment

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    Rose, Camille; Green, Michael; Webber, Steven; Ellis, Demetrius; Reyes, Jorges; Rowe, David

    2001-01-01

    Solid-organ transplant recipients are at risk for development of lymphoproliferative diseases. The purpose of this study was to examine the distribution of Epstein-Barr virus (EBV) load in the peripheral blood of pediatric transplant recipients who had become chronic viral load carriers (>8 copies/105 lymphocytes for >2 months). A total of 19 patients with viral loads ranging from 20 to 5,000 viral genome copies/105 lymphocytes were studied. Ten patients had no previous diagnosis of posttransplant lymphoproliferative disease (PT-LPD), while nine had recovered from a diagnosed case of PT-LPD. No portion of the peripheral blood viral load was detected in the cell-free plasma fraction. Viral DNA was found in a population of cells characterized as CD19hi and immunoglobulin D negative, a phenotype that is consistent with the virus being carried exclusively in the memory B-cell compartment of the peripheral blood. There was no difference in the compartmentalization based upon either the level of the viral load or the past diagnosis of an episode of PT-LPD. These results have implications for the design of tests to detect EBV infection and for the interpretation and use of positive EBV PCR assays in the management of transplant recipients. PMID:11283064

  17. Monitoring the systemic human memory B cell compartment of melanoma patients for anti-tumor IgG antibodies.

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    Amy E Gilbert

    Full Text Available Melanoma, a potentially lethal skin cancer, is widely thought to be immunogenic in nature. While there has been much focus on T cell-mediated immune responses, limited knowledge exists on the role of mature B cells. We describe an approach, including a cell-based ELISA, to evaluate mature IgG antibody responses to melanoma from human peripheral blood B cells. We observed a significant increase in antibody responses from melanoma patients (n = 10 to primary and metastatic melanoma cells compared to healthy volunteers (n = 10 (P<0.0001. Interestingly, we detected a significant reduction in antibody responses to melanoma with advancing disease stage in our patient cohort (n = 21 (P<0.0001. Overall, 28% of melanoma patient-derived B cell cultures (n = 1,800 compared to 2% of cultures from healthy controls (n = 600 produced antibodies that recognized melanoma cells. Lastly, a patient-derived melanoma-specific monoclonal antibody was selected for further study. This antibody effectively killed melanoma cells in vitro via antibody-mediated cellular cytotoxicity. These data demonstrate the presence of a mature systemic B cell response in melanoma patients, which is reduced with disease progression, adding to previous reports of tumor-reactive antibodies in patient sera, and suggesting the merit of future work to elucidate the clinical relevance of activating humoral immune responses to cancer.

  18. Monitoring the Systemic Human Memory B Cell Compartment of Melanoma Patients for Anti-Tumor IgG Antibodies

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    Gilbert, Amy E.; Karagiannis, Panagiotis; Dodev, Tihomir; Koers, Alexander; Lacy, Katie; Josephs, Debra H.; Takhar, Pooja; Geh, Jenny L. C.; Healy, Ciaran; Harries, Mark; Acland, Katharine M.; Rudman, Sarah M.; Beavil, Rebecca L.; Blower, Philip J.; Beavil, Andrew J.; Gould, Hannah J.; Spicer, James; Nestle, Frank O.; Karagiannis, Sophia N.

    2011-01-01

    Melanoma, a potentially lethal skin cancer, is widely thought to be immunogenic in nature. While there has been much focus on T cell-mediated immune responses, limited knowledge exists on the role of mature B cells. We describe an approach, including a cell-based ELISA, to evaluate mature IgG antibody responses to melanoma from human peripheral blood B cells. We observed a significant increase in antibody responses from melanoma patients (n = 10) to primary and metastatic melanoma cells compared to healthy volunteers (n = 10) (P<0.0001). Interestingly, we detected a significant reduction in antibody responses to melanoma with advancing disease stage in our patient cohort (n = 21) (P<0.0001). Overall, 28% of melanoma patient-derived B cell cultures (n = 1,800) compared to 2% of cultures from healthy controls (n = 600) produced antibodies that recognized melanoma cells. Lastly, a patient-derived melanoma-specific monoclonal antibody was selected for further study. This antibody effectively killed melanoma cells in vitro via antibody-mediated cellular cytotoxicity. These data demonstrate the presence of a mature systemic B cell response in melanoma patients, which is reduced with disease progression, adding to previous reports of tumor-reactive antibodies in patient sera, and suggesting the merit of future work to elucidate the clinical relevance of activating humoral immune responses to cancer. PMID:21559411

  19. T and B cells and PHA response of peripheral lymphocytes among atomic bomb survivors

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    Yamakido, Michio; Akiyama, Mitoshi; Dock, D.S.; Hamilton, H.B.; Awa, A.A.

    1982-07-01

    Little is known about immune compretence in atomic bomb survivors. The following results were observed from this study. T and B cells showed no change in proportion by age or exposure dose. The percentage of T cells was slightly lower in malignant tumor patients than in the control group. However, it was significantly higher in the group with chromosomal aberrations than in the control group. Phytohemagglutinin (PHA) response of peripheral lymphocytes decreased significantly with age in the 0 rad control group and the 200+ rad exposure group, particularly so in the latter. The malignant tumor group also showed lower PHA response than the control group. The PHA response of the chromosomal aberration group was significantly depressed compared with that of the control group. (author)

  20. Hepatocyte growth factor regulated tyrosine kinase substrate in the peripheral development and function of B-cells

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    Nagata, Takayuki; Murata, Kazuko; Murata, Ryo; Sun, Shu-lan; Saito, Yutaro; Yamaga, Shuhei; Tanaka, Nobuyuki; Tamai, Keiichi; Moriya, Kunihiko; Kasai, Noriyuki; Sugamura, Kazuo; Ishii, Naoto

    2014-01-01

    Highlights: •ESCRT-0 protein regulates the development of peripheral B-cells. •BCR expression on cell surface should be controlled by the endosomal-sorting system. •Hrs plays important roles in responsiveness to Ag stimulation in B lymphocytes. -- Abstract: Hepatocyte growth factor (HGF)-regulated tyrosine kinase substrate (Hrs) is a vesicular sorting protein that functions as one of the endosomal-sorting proteins required for transport (ESCRT). Hrs, which binds to ubiquitinated proteins through its ubiquitin-interacting motif (UIM), contributes to the lysosomal transport and degradation of ubiquitinated membrane proteins. However, little is known about the relationship between B-cell functions and ESCRT proteins in vivo. Here we examined the immunological roles of Hrs in B-cell development and functions using B-cell-specific Hrs-deficient (Hrs flox/flox ;mb1 cre/+ :Hrs-cKO) mice, which were generated using a cre-LoxP recombination system. Hrs deficiency in B-cells significantly reduced T-cell-dependent antibody production in vivo and impaired the proliferation of B-cells treated in vitro with an anti-IgM monoclonal antibody but not with LPS. Although early development of B-cells in the bone marrow was normal in Hrs-cKO mice, there was a significant decrease in the number of the peripheral transitional B-cells and marginal zone B-cells in the spleen of Hrs-cKO mice. These results indicate that Hrs plays important roles during peripheral development and physiological functions of B lymphocytes

  1. Hepatocyte growth factor regulated tyrosine kinase substrate in the peripheral development and function of B-cells

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    Nagata, Takayuki [Department of Pharmacy, Iwaki Meisei University, 5-5-1 Chuodai Iino, Iwaki, Fukushima 970-8551 (Japan); Department of Microbiology and Immunology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575 (Japan); Murata, Kazuko, E-mail: murata-k@iwakimu.ac.jp [Department of Pharmacy, Iwaki Meisei University, 5-5-1 Chuodai Iino, Iwaki, Fukushima 970-8551 (Japan); Murata, Ryo [Department of Pharmacy, Iwaki Meisei University, 5-5-1 Chuodai Iino, Iwaki, Fukushima 970-8551 (Japan); Sun, Shu-lan [Department of Microbiology and Immunology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575 (Japan); Saito, Yutaro; Yamaga, Shuhei [Department of Pharmacy, Iwaki Meisei University, 5-5-1 Chuodai Iino, Iwaki, Fukushima 970-8551 (Japan); Tanaka, Nobuyuki; Tamai, Keiichi [Division of Immunology, Miyagi Cancer Research Institute, 47-1 Nodayama, Medeshima-Shiode, Natori 981-1293 (Japan); Moriya, Kunihiko [Department of Pediatrics, Tohoku University School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai 980-8575 (Japan); Kasai, Noriyuki [Institute for Animal Experimentation, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575 (Japan); Sugamura, Kazuo [Division of Immunology, Miyagi Cancer Research Institute, 47-1 Nodayama, Medeshima-Shiode, Natori 981-1293 (Japan); Ishii, Naoto [Department of Microbiology and Immunology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575 (Japan)

    2014-01-10

    Highlights: •ESCRT-0 protein regulates the development of peripheral B-cells. •BCR expression on cell surface should be controlled by the endosomal-sorting system. •Hrs plays important roles in responsiveness to Ag stimulation in B lymphocytes. -- Abstract: Hepatocyte growth factor (HGF)-regulated tyrosine kinase substrate (Hrs) is a vesicular sorting protein that functions as one of the endosomal-sorting proteins required for transport (ESCRT). Hrs, which binds to ubiquitinated proteins through its ubiquitin-interacting motif (UIM), contributes to the lysosomal transport and degradation of ubiquitinated membrane proteins. However, little is known about the relationship between B-cell functions and ESCRT proteins in vivo. Here we examined the immunological roles of Hrs in B-cell development and functions using B-cell-specific Hrs-deficient (Hrs{sup flox/flox};mb1{sup cre/+}:Hrs-cKO) mice, which were generated using a cre-LoxP recombination system. Hrs deficiency in B-cells significantly reduced T-cell-dependent antibody production in vivo and impaired the proliferation of B-cells treated in vitro with an anti-IgM monoclonal antibody but not with LPS. Although early development of B-cells in the bone marrow was normal in Hrs-cKO mice, there was a significant decrease in the number of the peripheral transitional B-cells and marginal zone B-cells in the spleen of Hrs-cKO mice. These results indicate that Hrs plays important roles during peripheral development and physiological functions of B lymphocytes.

  2. Perioperative dynamic alterations in peripheral regulatory T and B cells in patients with hepatocellular carcinoma

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    Chen Tianxiang

    2012-01-01

    Full Text Available Abstract Background Intratumoral and circulating regulatory T cells (Tregs have been shown to be critical in the pathogenesis of hepatocellular carcinoma (HCC. However there is limited knowledge on the alterations of regulatory B cells (Bregs. We here investigated perioperative dynamic alterations of peripheral circulating Tregs and Bregs in HCC patients to reveal the relationship between regulatory lymphocytes and its clinical implications. Methods 36 patients with HCC, 6 with chronic hepatitis B infection and 10 healthy donors were enrolled for this study. Frequencies of peripheral Tregs and Bregs were measured by flow cytometry with antibodies against CD4, CD25, CD127, CD19 and IL-10 before, and after radical surgery. Then, clinical informatics of HCC patients was achieved through Digital Evaluation Score System (DESS for the assessment of disease severity. Finally, we analysed correlations between digitalized clinical features and kinetics of circulating regulatory lymphocytes. Results Level of circulating CD4+CD25+CD127- Tregs in HCC patients was significantly lower than that in healthy donors and patients with chronic hepatitis B infection before surgery, but was increased after surgery. Preoperative level of CD19+ IL-10+ Bregs in HCC patients was also significantly lower than the other groups. However it dramatically was elevated right after surgery and remained elevated compared to controls (about 7 days after surgery, P = 0.04. Frequency of circulating Tregs was correlated with circulating leukocytes, ferritin, and clinical features suggesting tumor aggressiveness including portal vein thrombosis, hepatic vein involvement and advanced clinical stages. Frequency of circulating Bregs was associated with Hepatitis B e Antigen (HBeAg and Hepatitis B virus (HBV DNA copy number. In addition, DESS was significantly and positively correlated with other staging systems. Conclusion Frequencies of peripheral Tregs and Bregs in HCC patients

  3. From lymphopoiesis to plasma cells differentiation, the age-related modifications of B cell compartment are influenced by "inflamm-ageing".

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    Bulati, Matteo; Caruso, Calogero; Colonna-Romano, Giuseppina

    2017-07-01

    Ageing is a complex process characterized by a general decline in physiological functions with increasing morbidity and mortality. The most important aspect of ageing is the chronic inflammatory status, named "inflamm-ageing", strictly associated with the deterioration of the immune function, termed "immunosenescence". Both are causes of increased susceptibility of elderly to infectious diseases, cancer, dementia, cardiovascular diseases and autoimmunity, and of a decreased response to vaccination. It has been widely demonstrated that ageing has a strong impact on the remodelling of the B cell branch of immune system. The first evident effect is the significant decrease in circulating B cells, primarily due to the reduction of new B cell coming from bone marrow (BM) progenitors, as inflammation directly impacts on B lymphopoiesis. Besides, in aged individuals, there is a shift from naïve to memory immunoglobulins production, accompanied by the impaired ability to produce high affinity protective antibodies against newly encountered antigens. This is accompanied by the increase of expanded clones of B cells, which correlates with poor health status. Age-related modifications also occur in naïve/memory B cells subsets. Indeed, in the elderly, there is a reduction of naïve B cells, accompanied by the expansion of memory B cells that show a senescence-associated phenotype. Finally, elderly show the impaired ability of memory B cells to differentiate into plasma cells. It can be concluded that inflammation is the leading cause of the age-related impairment of B cell compartment, which play certainly a key role in the development of age-related diseases. This makes study of B cells in the aged an important tool for monitoring immunosenescence, chronic inflammatory disorders and the effectiveness of vaccines or pharmacological therapies. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Homeostatic 'bystander' proliferation of human peripheral blood B cells in response to polyclonal T-cell stimulation in vitro.

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    Jasiulewicz, Aleksandra; Lisowska, Katarzyna A; Pietruczuk, Krzysztof; Frąckowiak, Joanna; Fulop, Tamas; Witkowski, Jacek M

    2015-11-01

    The mechanisms of maintenance of adequate numbers of B lymphocytes and of protective levels of immunoglobulins in the absence of antigenic (re)stimulation remain not fully understood. Meanwhile, our results presented here show that both peripheral blood naive and memory B cells can be activated strongly and non-specifically (in a mitogen-like fashion) in 5-day in vitro cultures of anti-CD3- or concanavalin A (Con A)-stimulated peripheral blood mononuclear cells of healthy people. This polyclonal, bystander activation of the B cells includes multiple divisions of most of them (assessed here by the flow cytometric technique of dividing cell tracking) and significant antibody [immunoglobulin M (IgM) and IgG] secretion. Observed proliferation of the CD19(+) B cells depends on contact with stimulated T helper (Th) cells (via CD40-CD40L interaction) and on the response of B cells to secreted interleukins IL-5, IL-10 and IL-4, and is correlated with the levels of these Th-derived molecules, while it does not involve the ligation of the BCR/CD19 complex. We suggest that the effect might reflect the situation occurring in vivo as the homeostatic proliferation of otherwise non-stimulated, peripheral B lymphocytes, providing an always ready pool for efficient antibody production to any new (or cognate) antigen challenge. © The Japanese Society for Immunology. 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. Comparison of immunological characteristics of peripheral, splenic and tonsilar naïve B cells by differential gene expression meta-analyses.

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    Chokeshai-u-saha, Kaj; Lepoivre, Cyrille; Grieco, Luca; Nguyen, Catherine; Ruxrungtham, Kiat

    2012-12-01

    Naïve B cells isolated from peripheral blood, spleen and tonsil are commonly used in human B cell studies. However, little has been written about their possible variations in immunological properties. This study compared differential gene expression in human naive B subsets by meta-analysis using expression data available in Gene Expression Onimbus (GEO). Gene expression files of the Affymetrix Human Genome U133A Array (Affymetrix) were downloaded to collect 21 total array data samples of peripheral naïve B cells (n=10), splenic naïve B cells (n=2), tonsilar naïve B cells (n=3), peripheral memory B cells (n=4) and splenic memory B cells (n=2). Prior to differential gene expression analyses, data were normalized in order to reduce non-biological variation among the datasets. Comparisons of peripheral naive B cells with their splenic and tonsilar counterparts showed remarkable differences in terms of gene expression (29 and 202 genes, respectively). However, only minor differences were detected between splenic and tonsilar naive B cells (10 genes), consistent with the clustering results classifying both of them as lymphoid naive B cells. Differential gene expression results also implied higher stimulating states of lymphoid naive B cells when compared with peripheral blood naive B cells. These included enhanced expressions of CD27, CR2, EGR1, GADD45B, ICAM1, ICOSLG, IGHA, IL6, MMP9, SAMSN1, SMAD7, TNFAIP3, but reduced HLA-DOB expression. Our findings suggest that results generated from peripheral naive B cells may not always be applicable to the biological activities of other lymphoid naïve B cells. Nonetheless, further biological study is warranted.

  6. COMPARTMENTS

    DEFF Research Database (Denmark)

    Binder, Janos X; Pletscher-Frankild, Sune; Tsafou, Kalliopi

    2014-01-01

    of the localization of a protein, it is thus necessary to consult multiple databases and prediction tools. To address this, we present the COMPARTMENTS resource, which integrates all sources listed above as well as the results of automatic text mining. The resource is automatically kept up to date with source...

  7. Maintenance of the marginal-zone B cell compartment specifically requires the RNA-binding protein ZFP36L1.

    Science.gov (United States)

    Newman, Rebecca; Ahlfors, Helena; Saveliev, Alexander; Galloway, Alison; Hodson, Daniel J; Williams, Robert; Besra, Gurdyal S; Cook, Charlotte N; Cunningham, Adam F; Bell, Sarah E; Turner, Martin

    2017-06-01

    RNA-binding proteins of the ZFP36 family are best known for inhibiting the expression of cytokines through binding to AU-rich elements in the 3' untranslated region and promoting mRNA decay. Here we identified an indispensable role for ZFP36L1 as the regulator of a post-transcriptional hub that determined the identity of marginal-zone B cells by promoting their proper localization and survival. ZFP36L1 controlled a gene-expression program related to signaling, cell adhesion and locomotion; it achieved this in part by limiting expression of the transcription factors KLF2 and IRF8, which are known to enforce the follicular B cell phenotype. These mechanisms emphasize the importance of integrating transcriptional and post-transcriptional processes by RNA-binding proteins for maintaining cellular identity among closely related cell types.

  8. Maintenance of the marginal zone B cell compartment specifically requires the RNA-binding protein ZFP36L1

    Science.gov (United States)

    Newman, Rebecca; Ahlfors, Helena; Saveliev, Alexander; Galloway, Alison; Hodson, Daniel J; Williams, Robert; Besra, Gurdyal S.; Cook, Charlotte N; Cunningham, Adam F; Bell, Sarah E; Turner, Martin

    2017-01-01

    RNA binding proteins (RBP) of the ZFP36 family are best known for inhibiting the expression of cytokines through binding to AU rich elements in the 3’UTR and promoting mRNA decay. Here we show an indispensible role for ZFP36L1 as the regulator of a post-transcriptional hub that determined the identity of marginal zone (MZ) B cells by promoting their proper localization and survival. ZFP36L1 controlled a gene expression program related to signaling, cell-adhesion and locomotion, in part by limiting the expression of the transcription factors KLF2 and IRF8, which are known to enforce the follicular B cell phenotype. These mechanisms emphasize the importance of integrating transcriptional and post-transcriptional processes by RBP for maintaining cellular identity between closely related cell types. PMID:28394372

  9. Variations of B cell subpopulations in peripheral blood of healthy Mexican population according to age: Relevance for diagnosis of primary immunodeficiencies.

    Science.gov (United States)

    Berrón-Ruíz, L; López-Herrera, G; Ávalos-Martínez, C E; Valenzuela-Ponce, C; Ramírez-SanJuan, E; Santoyo-Sánchez, G; Mújica Guzmán, F; Espinosa-Rosales, F J; Santos-Argumedo, L

    Peripheral blood B cells include lymphocytes at various stages of differentiation, each with a specific function in the immune response. All these stages show variations in percentage and absolute number throughout human life. The numbers and proportions of B subpopulation are influenced by factors such as gender, age, ethnicity, and lifestyle. This study establishes reference values according to age of peripheral blood B cell subtypes in healthy Mexican population. Peripheral blood from healthy new-borns and adults were analysed for total B cell subpopulations, using surface markers such as CD19, IgM, IgD, CD21, CD24, CD27, and CD38, to identify naïve, memory with and without isotype switch, double-negative, transitional, and plasmablast cells. We observed a significant variation in terms of frequency and absolute counts between all groups analysed. Values from each B cell subpopulation show variations according to age. In order to attempt to elucidate reference values for B cell subpopulation, the present study evaluated a population sample of healthy blood donors from this region. Values reported here can also be used as a tool for diagnosis of diseases in which B cell maturation is affected. Copyright © 2016 SEICAP. Published by Elsevier España, S.L.U. All rights reserved.

  10. Recipient dendritic cells, but not B cells, are required antigen-presenting cells for peripheral alloreactive CD8+ T-cell tolerance.

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    Mollov, J L; Lucas, C L; Haspot, F; Gaspar, J Kurtz C; Guzman, A; Sykes, M

    2010-03-01

    Induction of mixed allogeneic chimerism is a promising approach for achieving donor-specific tolerance, thereby obviating the need for life-long immunosuppression for solid organ allograft acceptance. In mice receiving a low dose (3Gy) of total body irradiation, allogeneic bone marrow transplantation combined with anti-CD154 tolerizes peripheral CD4 and CD8 T cells, allowing achievement of mixed chimerism with specific tolerance to donor. With this approach, peripheral CD8 T-cell tolerance requires recipient MHC class II, CD4 T cells, B cells and DCs. Recipient-type B cells from chimeras that were tolerant to donor still promoted CD8 T-cell tolerance, but their role could not be replaced by donor-type B cells. Using recipients whose B cells or DCs specifically lack MHC class I and/or class II or lack CD80 and CD86, we demonstrate that dendritic cells (DCs) must express CD80/86 and either MHC class I or class II to promote CD8 tolerance. In contrast, B cells, though required, did not need to express MHC class I or class II or CD80/86 to promote CD8 tolerance. Moreover, recipient IDO and IL-10 were not required. Thus, antigen presentation by recipient DCs and not by B cells is critical for peripheral alloreactive CD8 T cell tolerance.

  11. Distinct kinetics of memory B-cell and plasma-cell responses in peripheral blood following a blood-stage Plasmodium chabaudi infection in mice.

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    Eunice W Nduati

    2010-11-01

    Full Text Available B cell and plasma cell responses take place in lymphoid organs, but because of the inaccessibility of these organs, analyses of human responses are largely performed using peripheral blood mononuclear cells (PBMC. To determine whether PBMC are a useful source of memory B cells and plasma cells in malaria, and whether they reflect Plasmodium-specific B cell responses in spleen or bone marrow, we have investigated these components of the humoral response in PBMC using a model of Plasmodium chabaudi blood-stage infections in C57BL/6 mice. We detected memory B cells, defined as isotype-switched IgD(- IgM(- CD19(+ B cells, and low numbers of Plasmodium chabaudi Merozoite Surface Protein-1 (MSP1-specific memory B cells, in PBMC at all time points sampled for up to 90 days following primary or secondary infection. By contrast, we only detected CD138(+ plasma cells and MSP1-specific antibody-secreting cells within a narrow time frame following primary (days 10 to 25 or secondary (day 10 infection. CD138(+ plasma cells in PBMC at these times expressed CD19, B220 and MHC class II, suggesting that they were not dislodged bone-marrow long-lived plasma cells, but newly differentiated migratory plasmablasts migrating to the bone marrow; thus reflective of an ongoing or developing immune response. Our data indicates that PBMC can be a useful source for malaria-specific memory B cells and plasma cells, but extrapolation of the results to human malaria infections suggests that timing of sampling, particularly for plasma cells, may be critical. Studies should therefore include multiple sampling points, and at times of infection/immunisation when the B-cell phenotypes of interest are likely to be found in peripheral blood.

  12. Complement-dependent transport of antigen into B cell follicles

    DEFF Research Database (Denmark)

    Gonzalez, Santiago F.; Lukacs-Kornek, Veronika; Kuligowski, Michael P.

    2010-01-01

    an additional novel pathway in which complement C3 and its receptors enhance humoral immunity through delivery of Ag to the B cell compartment. In this review, we discuss this pathway and highlight several novel exceptions recently found with a model influenza vaccine, such as mannose-binding lectin...... opsonization of influenza and uptake by macrophages, and the capture of virus by dendritic cells residing in the medullary compartment of peripheral lymph nodes....

  13. Study on serum TNF-α level, B-cell count and T-cell subsets distribution in peripheral blood in patients with rheumatoid arthritis

    International Nuclear Information System (INIS)

    Shi Buqing

    2006-01-01

    Objective: To study the changes of serum TNF-α levels, B-cell count and T-cell subsets distribution in peripheral blood in patients with rheumatoid arthritis. Methods: Serum TNF-α levels (with RIA), B cell as well as T cell subsets distribution type (with monoclonal antibody technique) were examined in 37 patients with rheumatoid arthritis and 30 controls. Results Serum TNF-α levels and B lymphocytes count were significantly higher in the patients than those in controls (P 3 , CD 4 and CD 4 /CD 8 were obviously lower (P<0.01). Conclusion: Rheumatoid arthritis is an autoimmune disease with abnormal immunoregulation. (authors)

  14. Deficient CD4+ T cell priming and regression of CD8+ T cell functionality in virus-infected mice lacking a normal B cell compartment

    DEFF Research Database (Denmark)

    Christensen, Jan Pravsgaard; Kauffmann, Susanne Ørding; Thomsen, Allan Randrup

    2003-01-01

    of virus-specific CD4(+) T cells was markedly impaired in B(-/-) mice infected with either virus strain. Thus, our results indicate that B cells play an important role in antiviral immunity not only as Ab producers, but also in promoting an optimal and sustained T cell response. The T cell defects......In this study, we investigate the state of T cell-mediated immunity in B cell-deficient (B(-/-)) mice infected with two strains of lymphocytic choriomeningitis virus known to differ markedly in their capacity to persist. In B(-/-) C57BL mice infected with the more persisting virus, virus......-specific CD8(+) T cells are initially generated that are qualitatively similar to those in wild-type mice. However, although cell numbers are well sustained over time, the capacity to produce cytokines is rapidly impaired. In similarly infected B(-/-) BALB/c mice, virus-specific CD8(+) T cells are completely...

  15. Phenotypic characterization of autoreactive B cells--checkpoints of B cell tolerance in patients with systemic lupus erythematosus.

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    Annett M Jacobi

    Full Text Available DNA-reactive B cells play a central role in systemic lupus erythematosus (SLE; DNA antibodies precede clinical disease and in established disease correlate with renal inflammation and contribute to dendritic cell activation and high levels of type 1 interferon. A number of central and peripheral B cell tolerance mechanisms designed to control the survival, differentiation and activation of autoreactive B cells are thought to be disturbed in patients with SLE. The characterization of DNA-reactive B cells has, however, been limited by their low frequency in peripheral blood. Using a tetrameric configuration of a peptide mimetope of DNA bound by pathogenic anti-DNA antibodies, we can identify B cells producing potentially pathogenic DNA-reactive antibodies. We, therefore, characterized the maturation and differentiation states of peptide, (ds double stranded DNA cross-reactive B cells in the peripheral blood of lupus patients and correlated these with clinical disease activity. Flow cytometric analysis demonstrated a significantly higher frequency of tetramer-binding B cells in SLE patients compared to healthy controls. We demonstrated the existence of a novel tolerance checkpoint at the transition of antigen-naïve to antigen-experienced. We further demonstrate that patients with moderately active disease have more autoreactive B cells in both the antigen-naïve and antigen-experienced compartments consistent with greater impairment in B cell tolerance in both early and late checkpoints in these patients than in patients with quiescent disease. This methodology enables us to gain insight into the development and fate of DNA-reactive B cells in individual patients with SLE and paves the way ultimately to permit better and more customized therapies.

  16. The safe zone for hip arthroscopy: a cadaveric assessment of central, peripheral, and lateral compartment portal placement.

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    Robertson, William J; Kelly, Bryan T

    2008-09-01

    This study evaluated 11 arthroscopic portals (4 central, 4 peripheral, and 3 peritrochanteric) with regard to their proximity to neurovascular structures and the extra-articular path taken before entering their intended compartments. We established 11 standard portals in 10 cadaveric hips, under arthroscopic and fluoroscopic visualization, using 3/16-inch Steinmann pins. Each hip was dissected, and the relation of the pins to the pertinent anatomy was recorded to the nearest 1 mm. Only 2 of the 11 portals, the anterior and midanterior portals, came within 2 cm of a neurovascular structure before entering their respective compartments. The anterior portal placed the lateral femoral cutaneous nerve at risk, lying at a mean of 15.4 mm (range, 1 to 28 mm) away. The midanterior portal lies a mean of 19.2 mm (range, 5 to 42 mm) from the ascending branch of the lateral circumflex femoral artery. In addition, a small terminal branch of this artery courses a mean of 14.7 mm (range, 2 to 33 mm) and 10.1 mm (range, 1 to 23 mm) from the anterior portal and midanterior portal, respectively. This study showed that 11 arthroscopic portals can be safely inserted into the central, peripheral, and peritrochanteric compartments of the hip. The midanterior and anterior portals pass in close proximity to a small terminal branch of the ascending lateral circumflex femoral artery. The greatest risk still comes from the proximity of the anterior portal to the lateral femoral cutaneous nerve. However, a slightly more lateral location seems to provide substantial benefits. This study investigated 11 arthroscopic hip portals inserted in a standardized fashion. This knowledge should help surgeons place the necessary portals both safely and accurately.

  17. Immunoglobulin production induced in vitro by glucocorticoid hormones: T cell-dependent stimulation of immunoglobulin production without B cell proliferation in cultures of human peripheral blood lymphocytes

    International Nuclear Information System (INIS)

    Grayson, J.; Dooley, N.J.; Koski, I.R.; Blaese, R.M.

    1981-01-01

    The direct effects of steroid hormones on the production of immunoglobulins and DNA synthesis by human T and B lymphocytes was evaluated in cultures of peripheral blood mononuclear cells. As detected by a reverse hemolytic plaque assay, the addition of 0.1 mM to 10 nM hydrocortisone to lymphocytes in culture in the absence of other stimulants or mitogens, resulted in the dramatic induction of immunoglobulin production with responses comparable to those seen in similar cultures stimulated with pokeweed mitogen. Steroid-stimulated immunoglobulin production was first seen after 48 h and peaked at 8-10 d of culture. The production of IgG, IgA, and IgM was induced following incubation with steroid. Glucocorticoids, but not estrogens or androgens, were capable of mediating this effect, and only compounds with affinity for the glucocorticoid receptor were active. The induction of immunoglobulin production was dependent on both T cells and monocytes; cultures depleted of either cell type did not produce immunoglobulin when stimulated with glucocorticoid hormones. Proliferation of B cells or T cells could not be detected by [/sup 3/H]thymidine incorporation or total cell recovery from steroid-stimulated cultures, even though such cultures demonstrated marked increases in immunoglobulin production. The mechanism responsible for this functional maturation of B cells to become high rate immunoglobulin producing cells is as yet undefined, although it appears to involve more than merely steroid mediated inactivation of suppressor T cells

  18. Increased activity of cell membrane-associated prothrombinase, fibrinogen-like protein 2, in peripheral blood mononuclear cells of B-cell lymphoma patients.

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    Esther Rabizadeh

    Full Text Available Fibrinogen-like protein 2, FGL-2, was reported to be overexpressed in various cancer tissues, where it acts as a transmembrane prothrombinase. This study aims to determine the prothrombinase activity of FGL-2 in peripheral blood mononuclear cells (PBMC of patients with B-cell lymphoma. FGL-2 activity was determined in patients with B-cell lymphoma (n = 53, and healthy controls (n = 145. FGL-2 activity in patients at diagnosis increased 3 ± 0.3 fold (p < 0.001. Sensitivity and specificity of the test was established at 73.6% and 80.7%, respectively, using a cutoff of 150% activity over control. Moreover, FGL-2 activity in 10 of 11 patients in remission decreased by 76%. In contrast, no significant difference was observed in expression levels of fgl-2 gene in patients and controls. Taken together, our study indicates that FGL-2 prothrombinase activity in PBMC of lymphoma patients is increased in active disease and normalizes during remission, thus being a potential marker for follow up of lymphoma patients.

  19. Maintenance of host leukocytes in peripheral immune compartments following lethal irradiation and bone marrow reconstitution: implications for graft versus host disease.

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    Staley, Elizabeth M; Tanner, Scott M; Daft, Joseph G; Stanus, Andrea L; Martin, Steven M; Lorenz, Robin G

    2013-03-01

    Bone marrow reconstitution is utilized as a tool for disease treatment and as a research technique to elucidate the function of bone marrow derived cells. Clinically successful engraftment is indicated by the development of a functioning immune repertoire. In research, reconstitution is considered successful if >85% of splenic leukocytes are of donor origins. Previous work suggests that splenic reconstitution may not be indicative of reconstitution in the mucosa. We sought to evaluate mucosal reconstitution in animals following a standard bone marrow eradication and reconstitution technique. Bone marrow was harvested from adult B6.SJL donor mice (CD45.1) and injected via either the retro-orbital or intraperitoneal route into lethally irradiated B6 (CD45.2) adult or neonatal recipients respectively. The expression of CD45 by flow cytometry was used to calculate reconstitution with respect to immune compartment and cell type. In reconstituted adult animals 93.2±1.5% of splenic leukocytes expressed the donor CD45.1 antigen thus meeting the standard definition of reconstitution, however only 58.6±13.6% of intestinal lamina propria lymphocytes and 52.4±16.0% of intestinal intraepithelial lymphocytes were of donor origin, confirming splenic reconstitution fails to represent peripheral immune reconstitution. T-cells in the gastrointestinal tract are the most poorly reconstituted, while B-cells appear to be almost universally replaced by donor cells. The inadequate mucosal reconstitution was not corrected by evaluating later time points or by performing the bone marrow transfer during the neonatal period. This demonstration that substantial host T-cells remain in the intestinal mucosa after a "successful" bone marrow transplantation should cause a re-evaluation of data from research bone marrow chimera experiments, as well as the mechanisms for complications after clinical bone marrow transplantation. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. CD3+/CD16+CD56+ cell numbers in peripheral blood are correlated with higher tumor burden in patients with diffuse large B-cell lymphoma

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    Anna Twardosz

    2011-04-01

    Full Text Available Diffuse large B-cell lymphoma is the commonest histological type of malignant lymphoma, andremains incurable in many cases. Developing more efficient immunotherapy strategies will require betterunderstanding of the disorders of immune responses in cancer patients. NKT (natural killer-like T cells wereoriginally described as a unique population of T cells with the co-expression of NK cell markers. Apart fromtheir role in protecting against microbial pathogens and controlling autoimmune diseases, NKT cells havebeen recently revealed as one of the key players in the immune responses against tumors. The objective of thisstudy was to evaluate the frequency of CD3+/CD16+CD56+ cells in the peripheral blood of 28 diffuse largeB-cell lymphoma (DLBCL patients in correlation with clinical and laboratory parameters. Median percentagesof CD3+/CD16+CD56+ were significantly lower in patients with DLBCL compared to healthy donors(7.37% vs. 9.01%, p = 0.01; 4.60% vs. 5.81%, p = 0.03, although there were no differences in absolute counts.The frequency and the absolute numbers of CD3+/CD16+CD56+ cells were lower in advanced clinical stagesthan in earlier ones. The median percentage of CD3+/CD16+CD56+ cells in patients in Ann Arbor stages 1–2 was5.55% vs. 3.15% in stages 3–4 (p = 0.02, with median absolute counts respectively 0.26 G/L vs. 0.41 G/L (p == 0.02. The percentage and absolute numbers of CD3+/CD16+CD56+ cells were significantly higher in DL-BCL patients without B-symptoms compared to the patients with B-symptoms, (5.51% vs. 2.46%, p = 0.04;0.21 G/L vs. 0.44 G/L, p = 0.04. The percentage of CD3+/CD16+CD56+ cells correlated adversely with serumlactate dehydrogenase (R= –445; p < 0.05 which might influence NKT count. These figures suggest a relationshipbetween higher tumor burden and more aggressive disease and decreased NKT numbers. But it remains tobe explained whether low NKT cell counts in the peripheral blood of patients with DLBCL are the result

  1. The Decrease of Peripheral Blood CD4+ T Cells Indicates Abdominal Compartment Syndrome in Severe Acute Pancreatitis.

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    Yao Liu

    Full Text Available Few data are available on the role of T lymphocytes and inflammatory cytokines in abdominal compartment syndrome (ACS in severe acute pancreatitis (SAP. We conducted a retrospective study to assess the risk factors associated with ACS in SAP.A total of 76 SAP patients who were admitted within 24 hours after symptom onset in our study. There were 36 patients suffering from ACS and 40 from intra-abdominal hypertension (IAH. On the 1st, 3rd and 7th days after hospital admission, the following variables were assessed: serum value of C-reactive protein (CRP, and the proportions of peripheral CD4+ and CD8+ T lymphocytes. Acute Physiology and Chronic Health Evaluation II (APACHE II score, and computed tomography severity index (CTSI score were assessed on days 1 and 7 after hospitalization.Compared with the patients with IAH, ACS patients showed statistically higher CRP value on 7th day after hospital admission, proportions of CD4+ T cells on days 1, 3, 7 and CD4+/CD8+ ratio on day 1 were significantly lower (P < 0.05, respectively. A CD4+ T cell proportion of 30.3% on the 1st day indicated ACS with an area under the curve (AUC of 0.774, a sensitivity with 82.5% and specificity with 72.0%, respectively. Sensitivity/specificity for predicting ACS in SAP patients on day 1 was 70.0%/68.0% for CD4+/CD8+ ratio, 72.2%/65.0% for APACHE II score.The reduction of peripheral blood CD4+ T lymphocytes is associated with ACS in SAP, and may act as a potential predictor of ACS in SAP.

  2. [Proportion and significance of CD1d(hi)CD5⁺CD19⁺ regulatory B cell in peripheral blood of patients with neuromyelitis optica].

    Science.gov (United States)

    Yang, Fen; Huang, Dehui; Cheng, Chen; Wu, Weiping

    2015-03-01

    To detect the proportion of CD1d(hi)CD5⁺CD19⁺ regulatory B cells (Bregs) in peripheral blood of the patients with neuromyelitis optica (NMO), and explore whether CD1d(hi)CD5⁺CD19⁺ Bregs can play a role as a biomarker in the diagnosis of NMO versus multiple sclerosis (MS). Flow cytometry was performed to detect the proportion of CD1d(hi)CD5⁺CD19⁺ Bregs in peripheral blood from 44 cases of NMO, 38 cases of MS, and 30 healthy controls. The serum level of aquaporin-4 antibody (AQP4-Ab) of patients with NMO was detected by indirect immunofluorescence assay. The proportion of CD1d(hi)CD5⁺CD19⁺ Bregs in CD19⁺ B cells and lymphocytes was significantly lower in NMO group than in MS and control groups; however, there was no significant difference between MS group and control group. The proportion of CD1d(hi)CD5⁺CD19⁺ Bregs in CD19⁺ B cells and lymphocytes was lower in AQP4-Ab-positive NMO patients than in AQP4-Ab-negative NMO patients, and the difference was statistically significant. CD1d(hi)CD5⁺CD19⁺ Bregs may be a biomarker in the differential diagnosis of NMO versus MS.

  3. Alisertib in Combination With Vorinostat in Treating Patients With Relapsed or Recurrent Hodgkin Lymphoma, B-Cell Non-Hodgkin Lymphoma, or Peripheral T-Cell Lymphoma

    Science.gov (United States)

    2018-04-10

    Adult B Acute Lymphoblastic Leukemia; Adult T Acute Lymphoblastic Leukemia; Anaplastic Large Cell Lymphoma; Angioimmunoblastic T-Cell Lymphoma; Chronic Lymphocytic Leukemia; Extranodal Marginal Zone Lymphoma of Mucosa-Associated Lymphoid Tissue; Hepatosplenic T-Cell Lymphoma; Intraocular Lymphoma; Lymphomatous Involvement of Non-Cutaneous Extranodal Site; Mature T-Cell and NK-Cell Non-Hodgkin Lymphoma; Nodal Marginal Zone Lymphoma; Primary Cutaneous B-Cell Non-Hodgkin Lymphoma; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Hodgkin Lymphoma; Recurrent Adult Immunoblastic Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Adult T-Cell Leukemia/Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Mycosis Fungoides and Sezary Syndrome; Recurrent Non-Hodgkin Lymphoma; Recurrent Primary Cutaneous T-Cell Non-Hodgkin Lymphoma; Recurrent Small Lymphocytic Lymphoma; Refractory Chronic Lymphocytic Leukemia; Refractory Hairy Cell Leukemia; Small Intestinal Lymphoma; Splenic Marginal Zone Lymphoma; T-Cell Large Granular Lymphocyte Leukemia; Testicular Lymphoma; Waldenstrom Macroglobulinemia

  4. The tremorolytic action of beta-adrenoceptor blockers in essential, physiological and isoprenaline-induced tremor is mediated by beta-adrenoceptors located in a deep peripheral compartment.

    Science.gov (United States)

    Abila, B; Wilson, J F; Marshall, R W; Richens, A

    1985-10-01

    The effects of intravenous propranolol 100 micrograms kg-1, sotalol 500 micrograms kg-1, timolol 7.8 micrograms kg-1, atenolol 125 micrograms kg-1 and placebo on essential, physiological and isoprenaline-induced tremor were studied. These beta-adrenoceptor blocker doses produced equal reduction of standing-induced tachycardia in essential tremor patients. Atenolol produced significantly less reduction of essential and isoprenaline-induced tremor than the non-selective drugs, confirming the importance of beta 2-adrenoceptor blockade in these effects. Propranolol and sotalol produced equal maximal inhibition of isoprenaline-induced tremor but propranolol was significantly more effective in reducing essential tremor. The rate of development of the tremorolytic effect was similar in essential, physiological and isoprenaline-induced tremors but all tremor responses developed significantly more slowly than the heart rate responses. It is proposed that these results indicate that the tremorolytic activity of beta-adrenoceptor blockers in essential, physiological and isoprenaline-induced tremor is exerted via the same beta 2-adrenoceptors located in a deep peripheral compartment which is thought to be in the muscle spindles.

  5. B Cells and B Cell Blasts Withstand Cryopreservation While Retaining Their Functionality for Producing Antibody

    Directory of Open Access Journals (Sweden)

    Philipp Fecher

    2018-05-01

    Full Text Available In individuals who have once developed humoral immunity to an infectious/foreign antigen, the antibodies present in their body can mediate instant protection when the antigen re-enters. Such antigen-specific antibodies can be readily detected in the serum. Long term humoral immunity is, however, also critically dependent on the ability of memory B cells to engage in a secondary antibody response upon re-exposure to the antigen. Antibody molecules in the body are short lived, having a half-life of weeks, while memory B cells have a life span of decades. Therefore, the presence of serum antibodies is not always a reliable indicator of B cell memory and comprehensive monitoring of humoral immunity requires that both serum antibodies and memory B cells be assessed. The prevailing view is that resting memory B cells and B cell blasts in peripheral blood mononuclear cells (PBMC cannot be cryopreserved without losing their antibody secreting function, and regulated high throughput immune monitoring of B cell immunity is therefore confined to—and largely limited by—the need to test freshly isolated PBMC. Using optimized protocols for freezing and thawing of PBMC, and four color ImmunoSpot® analysis for the simultaneous detection of all immunoglobulin classes/subclasses we show here that both resting memory B cells and B cell blasts retain their ability to secrete antibody after thawing, and thus demonstrate the feasibility of B cell immune monitoring using cryopreserved PBMC.

  6. B Cells and B Cell Blasts Withstand Cryopreservation While Retaining Their Functionality for Producing Antibody.

    Science.gov (United States)

    Fecher, Philipp; Caspell, Richard; Naeem, Villian; Karulin, Alexey Y; Kuerten, Stefanie; Lehmann, Paul V

    2018-05-31

    In individuals who have once developed humoral immunity to an infectious/foreign antigen, the antibodies present in their body can mediate instant protection when the antigen re-enters. Such antigen-specific antibodies can be readily detected in the serum. Long term humoral immunity is, however, also critically dependent on the ability of memory B cells to engage in a secondary antibody response upon re-exposure to the antigen. Antibody molecules in the body are short lived, having a half-life of weeks, while memory B cells have a life span of decades. Therefore, the presence of serum antibodies is not always a reliable indicator of B cell memory and comprehensive monitoring of humoral immunity requires that both serum antibodies and memory B cells be assessed. The prevailing view is that resting memory B cells and B cell blasts in peripheral blood mononuclear cells (PBMC) cannot be cryopreserved without losing their antibody secreting function, and regulated high throughput immune monitoring of B cell immunity is therefore confined to-and largely limited by-the need to test freshly isolated PBMC. Using optimized protocols for freezing and thawing of PBMC, and four color ImmunoSpot ® analysis for the simultaneous detection of all immunoglobulin classes/subclasses we show here that both resting memory B cells and B cell blasts retain their ability to secrete antibody after thawing, and thus demonstrate the feasibility of B cell immune monitoring using cryopreserved PBMC.

  7. B cell repertoires in HLA-sensitized kidney transplant candidates undergoing desensitization therapy.

    Science.gov (United States)

    Beausang, John F; Fan, H Christina; Sit, Rene; Hutchins, Maria U; Jirage, Kshama; Curtis, Rachael; Hutchins, Edward; Quake, Stephen R; Yabu, Julie M

    2017-01-13

    Kidney transplantation is the most effective treatment for end-stage renal disease. Sensitization refers to pre-existing antibodies against human leukocyte antigen (HLA) protein and remains a major barrier to successful transplantation. Despite implementation of desensitization strategies, many candidates fail to respond. Our objective was to determine whether measuring B cell repertoires could differentiate candidates that respond to desensitization therapy. We developed an assay based on high-throughput DNA sequencing of the variable domain of the heavy chain of immunoglobulin genes to measure changes in B cell repertoires in 19 highly HLA-sensitized kidney transplant candidates undergoing desensitization and 7 controls with low to moderate HLA sensitization levels. Responders to desensitization had a decrease of 5% points or greater in cumulated calculated panel reactive antibody (cPRA) levels, and non-responders had no decrease in cPRA. Dominant B cell clones were not observed in highly sensitized candidates, suggesting that the B cells responsible for sensitization are either not present in peripheral blood or present at comparable levels to other circulating B cells. Candidates that responded to desensitization therapy had pre-treatment repertoires composed of a larger fraction of class-switched (IgG and IgA) isotypes compared to non-responding candidates. After B cell depleting therapy, the proportion of switched isotypes increased and the mutation frequencies of the remaining non-switched isotypes (IgM and IgD) increased in both responders and non-responders, perhaps representing a shift in the repertoire towards memory B cells or plasmablasts. Conversely, after transplantation, non-switched isotypes with fewer mutations increased, suggesting a shift in the repertoire towards naïve B cells. Relative abundance of different B cell isotypes is strongly perturbed by desensitization therapy and transplantation, potentially reflecting changes in the relative

  8. B cell biology: implications for treatment of systemic lupus erythematosus.

    Science.gov (United States)

    Anolik, J H

    2013-04-01

    B cells are critical players in the orchestration of properly regulated immune responses, normally providing protective immunity without autoimmunity. Balance in the B cell compartment is achieved through the finely regulated participation of multiple B cell populations with different antibody-dependent and independent functions. Both types of functions allow B cells to modulate other components of the innate and adaptive immune system. Autoantibody-independent B cell functions include antigen presentation, T cell activation and polarization, and dendritic cell modulation. Several of these functions are mediated by the ability of B cells to produce immunoregulatory cytokines and chemokines and by their critical contribution to lymphoid tissue development and organization including the development of ectopic tertiary lymphoid tissue. Additionally, the functional versatility of B cells enables them to play either protective or pathogenic roles in autoimmunity. In turn, B cell dysfunction has been critically implicated in the pathophysiology of systemic lupus erythematosus (SLE), a complex disease characterized by the production of autoantibodies and heterogeneous clinical involvement. Thus, the breakdown of B cell tolerance is a defining and early event in the disease process and may occur by multiple pathways, including alterations in factors that affect B cell activation thresholds, B cell longevity, and apoptotic cell processing. Once tolerance is broken, autoantibodies contribute to autoimmunity by multiple mechanisms including immune-complex mediated Type III hypersensitivity reactions, type II antibody-dependent cytotoxicity, and by instructing innate immune cells to produce pathogenic cytokines including IFNα, TNF and IL-1. The complexity of B cell functions has been highlighted by the variable success of B cell-targeted therapies in multiple autoimmune diseases, including those conventionally viewed as T cell-mediated conditions. Given the widespread

  9. Patellofemoral compartment

    International Nuclear Information System (INIS)

    Brown, T.; Quinn, S.F.; Erickson, S.J.; Cox, I.

    1990-01-01

    This paper evaluates the normal and abnormal patellofemoral compartment with axial MR imaging. Anatomic cryotome sections of the patellofemoral compartment were correlated with the corresponding MR images for identification of ligamentous structures and cartilaginous surfaces. Two hundred fifty-four patients who underwent both arthroscopy and axial MR imaging of the patellofemoral compartment underwent axial MR examinations, which included gradient-echo (TR 23, TE 14, flip angle 30 degrees), T1- weighted (TR 400, TE 20), and proton and T2-weighted (2,500/20/80) sequences. The results from the cryotome-MR correlation show that axial MR images of the patellofemoral compartment accurately depict the major ligamentous and cartilaginous components. The MR arthroscopic correlation showed that all pulse sequences were unreliable in depicting the more superficial changes of chondromalacia and the evaluation on synovial plica

  10. Compartment syndromes

    Science.gov (United States)

    Mubarak, S. J.; Pedowitz, R. A.; Hargens, A. R.

    1989-01-01

    The compartment syndrome is defined as a condition in which high pressure within a closed fascial space (muscle compartment) reduces capillary blood perfusion below the level necessary for tissue viability'. This condition occurs in acute and chronic (exertional) forms, and may be secondary to a variety of causes. The end-result of an extended period of elevated intramuscular pressure may be the development of irreversible tissue injury and Volkmann's contracture. The goal of treatment of the compartment syndrome is the reduction of intracompartmental pressure thus facilitating reperfusion of ischaemic tissue and this goal may be achieved by decompressive fasciotomy. Controversy exists regarding the critical pressure-time thresholds for surgical decompression and the optimal diagnostic methods of measuring intracompartmental pressures. This paper will update and review some current knowledge regarding the pathophysiology, aetiology, diagnosis, and treatment of the acute compartment syndrome.

  11. Cell of origin associated classification of B-cell malignancies by gene signatures of the normal B-cell hierarchy.

    Science.gov (United States)

    Johnsen, Hans Erik; Bergkvist, Kim Steve; Schmitz, Alexander; Kjeldsen, Malene Krag; Hansen, Steen Møller; Gaihede, Michael; Nørgaard, Martin Agge; Bæch, John; Grønholdt, Marie-Louise; Jensen, Frank Svendsen; Johansen, Preben; Bødker, Julie Støve; Bøgsted, Martin; Dybkær, Karen

    2014-06-01

    Recent findings have suggested biological classification of B-cell malignancies as exemplified by the "activated B-cell-like" (ABC), the "germinal-center B-cell-like" (GCB) and primary mediastinal B-cell lymphoma (PMBL) subtypes of diffuse large B-cell lymphoma and "recurrent translocation and cyclin D" (TC) classification of multiple myeloma. Biological classification of B-cell derived cancers may be refined by a direct and systematic strategy where identification and characterization of normal B-cell differentiation subsets are used to define the cancer cell of origin phenotype. Here we propose a strategy combining multiparametric flow cytometry, global gene expression profiling and biostatistical modeling to generate B-cell subset specific gene signatures from sorted normal human immature, naive, germinal centrocytes and centroblasts, post-germinal memory B-cells, plasmablasts and plasma cells from available lymphoid tissues including lymph nodes, tonsils, thymus, peripheral blood and bone marrow. This strategy will provide an accurate image of the stage of differentiation, which prospectively can be used to classify any B-cell malignancy and eventually purify tumor cells. This report briefly describes the current models of the normal B-cell subset differentiation in multiple tissues and the pathogenesis of malignancies originating from the normal germinal B-cell hierarchy.

  12. Foxp1 controls mature B cell survival and the development of follicular and B-1 B cells

    Science.gov (United States)

    Patzelt, Thomas; Keppler, Selina J.; Gorka, Oliver; Thoene, Silvia; Wartewig, Tim; Reth, Michael; Förster, Irmgard; Lang, Roland; Buchner, Maike; Ruland, Jürgen

    2018-01-01

    The transcription factor Foxp1 is critical for early B cell development. Despite frequent deregulation of Foxp1 in B cell lymphoma, the physiological functions of Foxp1 in mature B cells remain unknown. Here, we used conditional gene targeting in the B cell lineage and report that Foxp1 disruption in developing and mature B cells results in reduced numbers and frequencies of follicular and B-1 B cells and in impaired antibody production upon T cell-independent immunization in vivo. Moreover, Foxp1-deficient B cells are impaired in survival even though they exhibit an increased capacity to proliferate. Transcriptional analysis identified defective expression of the prosurvival Bcl-2 family gene Bcl2l1 encoding Bcl-xl in Foxp1-deficient B cells, and we identified Foxp1 binding in the regulatory region of Bcl2l1. Transgenic overexpression of Bcl2 rescued the survival defect in Foxp1-deficient mature B cells in vivo and restored peripheral B cell numbers. Thus, our results identify Foxp1 as a physiological regulator of mature B cell survival mediated in part via the control of Bcl-xl expression and imply that this pathway might contribute to the pathogenic function of aberrant Foxp1 expression in lymphoma. PMID:29507226

  13. Restoring balance to B cells in ADA deficiency.

    Science.gov (United States)

    Luning Prak, Eline T

    2012-06-01

    It is paradoxical that immunodeficiency disorders are associated with autoimmunity. Adenosine deaminase (ADA) deficiency, a cause of X-linked severe combined immunodeficiency (SCID), is a case in point. In this issue of the JCI, Sauer and colleagues investigate the B cell defects in ADA-deficient patients. They demonstrate that ADA patients receiving enzyme replacement therapy had B cell tolerance checkpoint defects. Remarkably, gene therapy with a retrovirus that expresses ADA resulted in the apparent correction of these defects, with normalization of peripheral B cell autoantibody frequencies. In vitro, agents that either block ADA or overexpress adenosine resulted in altered B cell receptor and TLR signaling. Collectively, these data implicate a B cell-intrinsic mechanism for alterations in B cell tolerance in the setting of partial ADA deficiency that is corrected by gene therapy.

  14. Circulating CXCR5+CD4+ T cells assist in the survival and growth of primary diffuse large B cell lymphoma cells through interleukin 10 pathway

    International Nuclear Information System (INIS)

    Cha, Zhanshan; Qian, Guangfang; Zang, Yan; Gu, Haihui; Huang, Yanyan; Zhu, Lishuang; Li, Jinqi; Liu, Yang; Tu, Xiaohua; Song, Haihan; Qian, Baohua

    2017-01-01

    Diffuse large B cell lymphoma (DLBCL) is a common and aggressive cancer caused by the malignant transformation of B cells. Although it has been established that the follicular helper T (Tfh) cells play a central role in B cell development, little information is available on their involvement in DLBCL pathogenesis. We studied the role of the peripheral Tfh equivalent, the CXCR5"+ CD4"+ T cells, in DLBCL. Data showed that compared to CXCR5"- CD4"+ T cells, CXCR5"+ CD4"+ T cells were significantly more effective at promoting the proliferation as well as inhibiting the apoptosis of primary autologous DLBCL tumor cells. Surprisingly, we found that at equal cell numbers, CXCR5"+ CD4"+ T cells in DLBCL patients secreted significantly less interleukin (IL)-21 than CXCR5"- CD4"+ T cells, while the level of IL-10 secretion was significant elevated in the CXCR5"+ compartment compared to the CXCR5"- compartment. Neutralization of IL-10 in the primary DLBCL-CXCR5"+ CD4"+ T cell coculture compromised the CXCR5"+ CD4"+ T cell-mediated pro-tumor effects, in a manner that was dependent on the concentration of anti-IL-10 antibodies. The CXCR5"+ compartment also contained significantly lower frequencies of cytotoxic CD4"+ T cells than the CXCR5"- compartment. In conclusion, our investigations discovered a previously unknown pro-tumor role of CXCR5-expressing circulating CD4"+ T cells, which assisted the survival and proliferation of primary DLBCL cells through IL-10. - Highlights: • We studied the role of the peripheral Tfh in DLBCL. • Tfh were effective at promoting the proliferation of primary DLBCL tumor cells. • Tfh were effective at inhibiting the apoptosis of primary DLBCL tumor cells. • IL-10 secretion in Tfh was significant elevated in DLBCL. • Neutralization of IL-10 compromised Tfh-mediated pro-tumor effects.

  15. Study of biological compartments

    International Nuclear Information System (INIS)

    Rocha, A.F.G. da

    1976-01-01

    The several types of biological compartments are studied such as monocompartmental system, one-compartment balanced system irreversible fluxes, two closed compartment system, three compartment systems, catenary systems and mammilary systems [pt

  16. Smudge cells in peripheral blood smears did not differentiate chronic lymphocytic leukemia from other B-cell chronic lymphoprolipherative diseases Sombras nucleares no esfregaço do sangue periférico não diferenciam a leucemia linfocítica crônica das outras doenças linfoproliferativas B crônicas

    Directory of Open Access Journals (Sweden)

    Daniel M. Matos

    2009-01-01

    Full Text Available Smudge cells has been classically associated with chronic lymphocytic leukemia (CLL, but they are found in peripheral blood tests for other chronic B-cell lymphoproliferative diseases (CLD. We investigated whether the percentage of smudge cells in peripheral blood smears can be used in the clinical practice to differentiate CLL from other B-cell CLD. The peripheral blood smears of 63 patients with the diagnosis of CLL and 62 with other B-cell CLD were analyzed. Three hundred cells (both lymphoid cells and smudge cells were counted for each peripheral blood smear. A comparison of the percentage of smudge cells between the two groups was performed and, subsequently, 5 cut-off values were fixed (10%, 20%, 30%, 40% and 50% of smudge cells with the aim of defining cases as "positive" or "negative" for smudge cells and verifying whether there are any differences between CLL and the other B-cell CLD. The percentage of smudge cells in patients with CLL (median 26%, 4%-86% was higher than in patients with B-cell CLD (median 14%, 1%-64%. However, none of the cut-off values tested presented suitable values of sensitivity, specificity and positive predictive value to separate the two groups. As it is necessary to have a single cut-off value with high sensitivity, specificity and positive predictive value to infer the diagnosis of CLL in the clinical practice, we concluded that smudge cells are not fitting to differentiate CLL from other B-cell CLD.As sombras nucleares têm sido classicamente associadasà leucemia linfocítica crônica (LLC, embora possam ser encontradas nos esfregaços do sangue periférico de outras doenças linfoproliferativas B crônicas (DLBC. Nesse estudo, nós investigamos se a porcentagem de sombras nucleares nos esfregaços do sangue periférico pode ser utilizada na prática clínica da hematologia para diferenciar a LLC das outras DLBC. Foram analisados os esfregaços do sangue periférico de 63 pacientes com o diagnóstico de LLC

  17. Two-stage, in silico deconvolution of the lymphocyte compartment of the peripheral whole blood transcriptome in the context of acute kidney allograft rejection.

    Science.gov (United States)

    Shannon, Casey P; Balshaw, Robert; Ng, Raymond T; Wilson-McManus, Janet E; Keown, Paul; McMaster, Robert; McManus, Bruce M; Landsberg, David; Isbel, Nicole M; Knoll, Greg; Tebbutt, Scott J

    2014-01-01

    Acute rejection is a major complication of solid organ transplantation that prevents the long-term assimilation of the allograft. Various populations of lymphocytes are principal mediators of this process, infiltrating graft tissues and driving cell-mediated cytotoxicity. Understanding the lymphocyte-specific biology associated with rejection is therefore critical. Measuring genome-wide changes in transcript abundance in peripheral whole blood cells can deliver a comprehensive view of the status of the immune system. The heterogeneous nature of the tissue significantly affects the sensitivity and interpretability of traditional analyses, however. Experimental separation of cell types is an obvious solution, but is often impractical and, more worrying, may affect expression, leading to spurious results. Statistical deconvolution of the cell type-specific signal is an attractive alternative, but existing approaches still present some challenges, particularly in a clinical research setting. Obtaining time-matched sample composition to biologically interesting, phenotypically homogeneous cell sub-populations is costly and adds significant complexity to study design. We used a two-stage, in silico deconvolution approach that first predicts sample composition to biologically meaningful and homogeneous leukocyte sub-populations, and then performs cell type-specific differential expression analysis in these same sub-populations, from peripheral whole blood expression data. We applied this approach to a peripheral whole blood expression study of kidney allograft rejection. The patterns of differential composition uncovered are consistent with previous studies carried out using flow cytometry and provide a relevant biological context when interpreting cell type-specific differential expression results. We identified cell type-specific differential expression in a variety of leukocyte sub-populations at the time of rejection. The tissue-specificity of these differentially

  18. Two-stage, in silico deconvolution of the lymphocyte compartment of the peripheral whole blood transcriptome in the context of acute kidney allograft rejection.

    Directory of Open Access Journals (Sweden)

    Casey P Shannon

    Full Text Available Acute rejection is a major complication of solid organ transplantation that prevents the long-term assimilation of the allograft. Various populations of lymphocytes are principal mediators of this process, infiltrating graft tissues and driving cell-mediated cytotoxicity. Understanding the lymphocyte-specific biology associated with rejection is therefore critical. Measuring genome-wide changes in transcript abundance in peripheral whole blood cells can deliver a comprehensive view of the status of the immune system. The heterogeneous nature of the tissue significantly affects the sensitivity and interpretability of traditional analyses, however. Experimental separation of cell types is an obvious solution, but is often impractical and, more worrying, may affect expression, leading to spurious results. Statistical deconvolution of the cell type-specific signal is an attractive alternative, but existing approaches still present some challenges, particularly in a clinical research setting. Obtaining time-matched sample composition to biologically interesting, phenotypically homogeneous cell sub-populations is costly and adds significant complexity to study design. We used a two-stage, in silico deconvolution approach that first predicts sample composition to biologically meaningful and homogeneous leukocyte sub-populations, and then performs cell type-specific differential expression analysis in these same sub-populations, from peripheral whole blood expression data. We applied this approach to a peripheral whole blood expression study of kidney allograft rejection. The patterns of differential composition uncovered are consistent with previous studies carried out using flow cytometry and provide a relevant biological context when interpreting cell type-specific differential expression results. We identified cell type-specific differential expression in a variety of leukocyte sub-populations at the time of rejection. The tissue-specificity of

  19. Early depletion of proliferating B cells of germinal center in rapidly progressive simian immunodeficiency virus infection

    International Nuclear Information System (INIS)

    Zhang Zhiqiang; Casimiro, Danilo R.; Schleif, William A.; Chen, Minchun; Citron, Michael; Davies, Mary-Ellen; Burns, Janine; Liang, Xiaoping; Fu, Tong-Ming; Handt, Larry; Emini, Emilio A.; Shiver, John W.

    2007-01-01

    Lack of virus specific antibody response is commonly observed in both HIV-1-infected humans and SIV-infected monkeys with rapid disease progression. However, the mechanisms underlying this important observation still remain unclear. In a titration study of a SIVmac239 viral stock, three out of six animals with viral inoculation rapidly progressed to AIDS within 5 months. Unexpectedly, there was no obvious depletion of CD4 + T cells in both peripheral and lymph node (LN) compartments in these animals. Instead, progressive depletion of proliferating B cells and disruption of the follicular dendritic cell (FDC) network in germinal centers (GC) was evident in the samples collected at as early as 20 days after viral challenge. This coincided with undetectable, or weak and transient, virus-specific antibody responses over the course of infection. In situ hybridization of SIV RNA in the LN samples revealed a high frequency of SIV productively infected cells and large amounts of accumulated viral RNA in the GCs in these animals. Early severe depletion of GC proliferating B cells and disruption of the FDC network may thus result in an inability to mount a virus-specific antibody response in rapid progressors, which has been shown to contribute to accelerated disease progression of SIV infection

  20. Altered B cell homeostasis and Toll-like receptor 9-driven response in patients affected by autoimmune polyglandular syndrome Type 1: Altered B cell phenotype and dysregulation of the B cell function in APECED patients.

    Science.gov (United States)

    Perri, Valentina; Gianchecchi, Elena; Scarpa, Riccardo; Valenzise, Mariella; Rosado, Maria Manuela; Giorda, Ezio; Crinò, Antonino; Cappa, Marco; Barollo, Susi; Garelli, Silvia; Betterle, Corrado; Fierabracci, Alessandra

    2017-02-01

    APECED is a T-cell mediated disease with increased frequencies of CD8+ effector and reduction of FoxP3+ T regulatory cells. Antibodies against affected organs and neutralizing to cytokines are found in the peripheral blood. The contribution of B cells to multiorgan autoimmunity in Aire-/- mice was reported opening perspectives on the utility of anti-B cell therapy. We aimed to analyse the B cell phenotype of APECED patients compared to age-matched controls. FACS analysis was conducted on PBMC in basal conditions and following CpG stimulation. Total B and switched memory (SM) B cells were reduced while IgM memory were increased in patients. In those having more than 15 years from the first clinical manifestation the defect included also mature and transitional B cells; total memory B cells were increased, while SM were unaffected. In patients with shorter disease duration, total B cells were unaltered while SM and IgM memory behaved as in the total group. A defective B cell proliferation was detected after 4day-stimulation. In conclusion APECED patients show, in addition to a significant alteration of the B cell phenotype, a dysregulation of the B cell function involving peripheral innate immune mechanisms particularly those with longer disease duration. Copyright © 2016 Elsevier GmbH. All rights reserved.

  1. Perturbation of B Cell Gene Expression Persists in HIV-Infected Children Despite Effective Antiretroviral Therapy and Predicts H1N1 Response.

    Science.gov (United States)

    Cotugno, Nicola; De Armas, Lesley; Pallikkuth, Suresh; Rinaldi, Stefano; Issac, Biju; Cagigi, Alberto; Rossi, Paolo; Palma, Paolo; Pahwa, Savita

    2017-01-01

    Despite effective antiretroviral therapy (ART), HIV-infected individuals with apparently similar clinical and immunological characteristics can vary in responsiveness to vaccinations. However, molecular mechanisms responsible for such impairment, as well as biomarkers able to predict vaccine responsiveness in HIV-infected children, remain unknown. Following the hypothesis that a B cell qualitative impairment persists in HIV-infected children (HIV) despite effective ART and phenotypic B cell immune reconstitution, the aim of the current study was to investigate B cell gene expression of HIV compared to age-matched healthy controls (HCs) and to determine whether distinct gene expression patterns could predict the ability to respond to influenza vaccine. To do so, we analyzed prevaccination transcriptional levels of a 96-gene panel in equal numbers of sort-purified B cell subsets (SPBS) isolated from peripheral blood mononuclear cells using multiplexed RT-PCR. Immune responses to H1N1 antigen were determined by hemaglutination inhibition and memory B cell ELISpot assays following trivalent-inactivated influenza vaccination (TIV) for all study participants. Although there were no differences in terms of cell frequencies of SPBS between HIV and HC, the groups were distinguishable based upon gene expression analyses. Indeed, a 28-gene signature, characterized by higher expression of genes involved in the inflammatory response and immune activation was observed in activated memory B cells (CD27 + CD21 - ) from HIV when compared to HC despite long-term viral control (>24 months). Further analysis, taking into account H1N1 responses after TIV in HIV participants, revealed that a 25-gene signature in resting memory (RM) B cells (CD27 + CD21 + ) was able to distinguish vaccine responders from non-responders (NR). In fact, prevaccination RM B cells of responders showed a higher expression of gene sets involved in B cell adaptive immune responses ( APRIL, BTK, BLIMP1 ) and

  2. The role of complement receptors type 1 (CR1, CD35) and 2 (CR2, CD21) in promoting C3 fragment deposition and membrane attack complex formation on normal peripheral human B cells

    DEFF Research Database (Denmark)

    Nielsen, Claus Henrik; Pedersen, Morten Løbner; Marquart, Hanne Vibeke Hansen

    2002-01-01

    Normal human B lymphocytes are known to activate the alternative pathway (AP) of complement, leading to C3-fragment deposition and membrane attack complex (MAC) formation. The process is mediated via complement receptor type 2 (CR2, CD21), with complement receptor type 1 (CR1, CD35) playing...... a subsidiary role. In this study, we examine the relative contributions of CR1 and CR2 to the deposition of C3 fragments and MAC on B lymphocytes under circumstances where all complement pathways are operational. C3-fragment deposition and MAC formation were assessed on human peripheral B lymphocytes...... in the presence of 30% autologous serum. Blocking the CR2 ligand-binding site with monoclonal antibody (mAb) FE8 resulted in significant reduction (37.9+/-11.9%) in C3-fragment deposition, whereas MAC formation was only marginally affected (12.1+/-22.2% reduction). Blocking the CR1 binding-site resulted...

  3. A role for gut-associated lymphoid tissue in shaping the human B cell repertoire.

    Science.gov (United States)

    Vossenkämper, Anna; Blair, Paul A; Safinia, Niloufar; Fraser, Louise D; Das, Lisa; Sanders, Theodore J; Stagg, Andrew J; Sanderson, Jeremy D; Taylor, Kirstin; Chang, Fuju; Choong, Lee M; D'Cruz, David P; Macdonald, Thomas T; Lombardi, Giovanna; Spencer, Jo

    2013-08-26

    We have tracked the fate of immature human B cells at a critical stage in their development when the mature B cell repertoire is shaped. We show that a major subset of bone marrow emigrant immature human B cells, the transitional 2 (T2) B cells, homes to gut-associated lymphoid tissue (GALT) and that most T2 B cells isolated from human GALT are activated. Activation in GALT is a previously unknown potential fate for immature human B cells. The process of maturation from immature transitional B cell through to mature naive B cell includes the removal of autoreactive cells from the developing repertoire, a process which is known to fail in systemic lupus erythematosus (SLE). We observe that immature B cells in SLE are poorly equipped to access the gut and that gut immune compartments are depleted in SLE. Thus, activation of immature B cells in GALT may function as a checkpoint that protects against autoimmunity. In healthy individuals, this pathway may be involved in generating the vast population of IgA plasma cells and also the enigmatic marginal zone B cell subset that is poorly understood in humans.

  4. Endothelial Plasmalemma Vesicle Associated Protein regulates the homeostasis of splenic immature B cell and B1 B cells

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    Elgueta, Raul; Tse, Dan; Deharvengt, Sophie J.; Luciano, Marcus R.; Carriere, Catherine; Noelle, Randolph J.; Stan, Radu V.

    2016-01-01

    Plasmalemma vesicle associated protein (Plvap) is an endothelial protein with roles in endothelial diaphragm formation and maintenance of basal vascular permeability. At the same time Plvap has roles in immunity by facilitating leukocyte diapedesis at inflammatory sites and controlling peripheral lymph node morphogenesis and the entry of soluble antigens into lymph node conduits. Based on its postulated role in diapedesis, we have investigated the role of Plvap in hematopoiesis and show that deletion of Plvap results in a dramatic decrease of IgM+IgDlo B cells in both the spleen and peritoneal cavity. Tissue specific deletion of Plvap demonstrates that the defect is B cell extrinsic, as B cell and pan hematopoietic Plvap deletion has no effect on IgM+IgDlo B cell numbers. Endothelial specific deletion of Plvap in the embryo or at adult stage recapitulates the full Plvap knockout phenotype whereas endothelial specific reconstitution of Plvap under the Chd5 promoter rescues the IgM+IgDlo B cell phenotype. Taken together, these results show that Plvap expression in endothelial cells is important in the maintenance of IgM+ B cells in the spleen and peritoneal cavity. PMID:27742829

  5. Endothelial Plasmalemma Vesicle-Associated Protein Regulates the Homeostasis of Splenic Immature B Cells and B-1 B Cells.

    Science.gov (United States)

    Elgueta, Raul; Tse, Dan; Deharvengt, Sophie J; Luciano, Marcus R; Carriere, Catherine; Noelle, Randolph J; Stan, Radu V

    2016-11-15

    Plasmalemma vesicle-associated protein (Plvap) is an endothelial protein with roles in endothelial diaphragm formation and maintenance of basal vascular permeability. At the same time, Plvap has roles in immunity by facilitating leukocyte diapedesis at inflammatory sites and controlling peripheral lymph node morphogenesis and the entry of soluble Ags into lymph node conduits. Based on its postulated role in diapedesis, we have investigated the role of Plvap in hematopoiesis and show that deletion of Plvap results in a dramatic decrease of IgM + IgD lo B cells in both the spleen and the peritoneal cavity. Tissue-specific deletion of Plvap demonstrates that the defect is B cell extrinsic, because B cell and pan-hematopoietic Plvap deletion has no effect on IgM + IgD lo B cell numbers. Endothelial-specific deletion of Plvap in the embryo or at adult stage recapitulates the full Plvap knockout phenotype, whereas endothelial-specific reconstitution of Plvap under the Chd5 promoter rescues the IgM + IgD lo B cell phenotype. Taken together, these results show that Plvap expression in endothelial cells is important in the maintenance of IgM + B cells in the spleen and peritoneal cavity. Copyright © 2016 by The American Association of Immunologists, Inc.

  6. B cells in operational tolerance.

    Science.gov (United States)

    Chesneau, M; Danger, R; Soulillou, J-P; Brouard, S

    2018-02-16

    Transplantation is currently the therapy of choice for endstage organ failure even though it requires long-term immunosuppresive therapy, with its numerous side effects, for acceptance of the transplanted organ. In rare cases however, patients develop operational tolerance, that is, graft survival without immunosuppression. Studies conducted on these patients reveal genetic, phenotypic, and functional signatures. They provide a better understanding of the immunological mechanisms involved in operational tolerance and define biomarkers that could be used to adapt immunosuppressive treatment to the individual, safely reduce immunosuppression doses, and ideally and safely guide immunosuppression withdrawal. This review summarizes studies that suggest a role for B cells as biomarkers of operational tolerance and discusses the use of B cells as a predictive tool for immunologic risk. Copyright © 2018. Published by Elsevier Inc.

  7. Influence of In Vitro IL-2 or IL-15 Alone or in Combination with Hsp 70 Derived 14-Mer Peptide (TKD on the Expression of NK Cell Activatory and Inhibitory Receptors on Peripheral Blood T Cells, B Cells and NKT Cells.

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    Ilona Hromadnikova

    Full Text Available Previous studies from Multhoff and colleagues reported that plasma membrane Hsp70 acts as a tumour-specific recognition structure for activated NK cells, and that the incubation of NK cells with Hsp70 and/or a 14-mer peptide derived from the N-terminal sequence of Hsp70 (TKDNNLLGRFELSG, TKD, aa 450-463 plus a low dose of IL-2 triggers NK cell proliferation and migration, and their capacity to kill cancer cells expressing membrane Hsp70. Herein, we have used flow cytometry to determine the influence of in vitro stimulation of peripheral blood mononuclear cells from healthy individuals with IL-2 or IL-15, either alone or in combination with TKD peptide on the cell surface expression of CD94, NK cell activatory receptors (CD16, NK2D, NKG2C, NKp30, NKp44, NKp46, NKp80, KIR2DL4, DNAM-1 and LAMP1 and NK cell inhibitory receptors (NKG2A, KIR2DL2/L3, LIR1/ILT-2 and NKR-P1A by CD3+CD56+ (NKT, CD3+CD4+, CD3+CD8+ and CD19+ populations. NKG2D, DNAM-1, LAMP1 and NKR-P1A expression was upregulated after the stimulation with IL-2 or IL-15 alone or in combination with TKD in NKT, CD8+ T cells and B cells. CD94 was upregulated in NKT and CD8+ T cells. Concurrently, an increase in a number of CD8+ T cells expressing LIR1/ILT-2 and CD4+ T cells positive for NKR-P1A was observed. The proportion of CD8+ T cells that expressed NKG2D was higher after IL-2/TKD treatment, when compared with IL-2 treatment alone. In comparison with IL-15 alone, IL-15/TKD treatment increased the proportion of NKT cells that were positive for CD94, LAMP1 and NKRP-1A. The more potent effect of IL-15/TKD on cell surface expression of NKG2D, LIR1/ILT-2 and NKRP-1A was observed in B cells compared with IL-15 alone. However, this increase was not of statistical significance. IL-2/TKD induced significant upregulation of LAMP1 in CD8+ T cells compared with IL-2 alone. Besides NK cells, other immunocompetent cells present within the fraction of peripheral blood mononuclear cells were influenced by

  8. Influence of In Vitro IL-2 or IL-15 Alone or in Combination with Hsp 70 Derived 14-Mer Peptide (TKD) on the Expression of NK Cell Activatory and Inhibitory Receptors on Peripheral Blood T Cells, B Cells and NKT Cells

    Science.gov (United States)

    Hromadnikova, Ilona; Li, Shuang; Kotlabova, Katerina; Dickinson, Anne M.

    2016-01-01

    Previous studies from Multhoff and colleagues reported that plasma membrane Hsp70 acts as a tumour-specific recognition structure for activated NK cells, and that the incubation of NK cells with Hsp70 and/or a 14-mer peptide derived from the N-terminal sequence of Hsp70 (TKDNNLLGRFELSG, TKD, aa 450–463) plus a low dose of IL-2 triggers NK cell proliferation and migration, and their capacity to kill cancer cells expressing membrane Hsp70. Herein, we have used flow cytometry to determine the influence of in vitro stimulation of peripheral blood mononuclear cells from healthy individuals with IL-2 or IL-15, either alone or in combination with TKD peptide on the cell surface expression of CD94, NK cell activatory receptors (CD16, NK2D, NKG2C, NKp30, NKp44, NKp46, NKp80, KIR2DL4, DNAM-1 and LAMP1) and NK cell inhibitory receptors (NKG2A, KIR2DL2/L3, LIR1/ILT-2 and NKR-P1A) by CD3+CD56+ (NKT), CD3+CD4+, CD3+CD8+ and CD19+ populations. NKG2D, DNAM-1, LAMP1 and NKR-P1A expression was upregulated after the stimulation with IL-2 or IL-15 alone or in combination with TKD in NKT, CD8+ T cells and B cells. CD94 was upregulated in NKT and CD8+ T cells. Concurrently, an increase in a number of CD8+ T cells expressing LIR1/ILT-2 and CD4+ T cells positive for NKR-P1A was observed. The proportion of CD8+ T cells that expressed NKG2D was higher after IL-2/TKD treatment, when compared with IL-2 treatment alone. In comparison with IL-15 alone, IL-15/TKD treatment increased the proportion of NKT cells that were positive for CD94, LAMP1 and NKRP-1A. The more potent effect of IL-15/TKD on cell surface expression of NKG2D, LIR1/ILT-2 and NKRP-1A was observed in B cells compared with IL-15 alone. However, this increase was not of statistical significance. IL-2/TKD induced significant upregulation of LAMP1 in CD8+ T cells compared with IL-2 alone. Besides NK cells, other immunocompetent cells present within the fraction of peripheral blood mononuclear cells were influenced by the treatment

  9. Circulating CXCR5+CD4+ T cells assist in the survival and growth of primary diffuse large B cell lymphoma cells through interleukin 10 pathway

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    Cha, Zhanshan [Department of Transfusion, Changhai Hospital, Second Military Medical University, Shanghai 200433 (China); Qian, Guangfang [Department of Endocrinology, Zhangqiu Municipal Hospital of Traditional Chinese Medicine, Zhangqiu, Shandong 250200 (China); Zang, Yan; Gu, Haihui; Huang, Yanyan; Zhu, Lishuang; Li, Jinqi; Liu, Yang; Tu, Xiaohua [Department of Transfusion, Changhai Hospital, Second Military Medical University, Shanghai 200433 (China); Song, Haihan [Emergency Center, East Hospital, Shanghai 200120 (China); Qian, Baohua, E-mail: qianbhl963@163.com [Department of Transfusion, Changhai Hospital, Second Military Medical University, Shanghai 200433 (China)

    2017-01-01

    Diffuse large B cell lymphoma (DLBCL) is a common and aggressive cancer caused by the malignant transformation of B cells. Although it has been established that the follicular helper T (Tfh) cells play a central role in B cell development, little information is available on their involvement in DLBCL pathogenesis. We studied the role of the peripheral Tfh equivalent, the CXCR5{sup +} CD4{sup +} T cells, in DLBCL. Data showed that compared to CXCR5{sup -} CD4{sup +} T cells, CXCR5{sup +} CD4{sup +} T cells were significantly more effective at promoting the proliferation as well as inhibiting the apoptosis of primary autologous DLBCL tumor cells. Surprisingly, we found that at equal cell numbers, CXCR5{sup +} CD4{sup +} T cells in DLBCL patients secreted significantly less interleukin (IL)-21 than CXCR5{sup -} CD4{sup +} T cells, while the level of IL-10 secretion was significant elevated in the CXCR5{sup +} compartment compared to the CXCR5{sup -} compartment. Neutralization of IL-10 in the primary DLBCL-CXCR5{sup +} CD4{sup +} T cell coculture compromised the CXCR5{sup +} CD4{sup +} T cell-mediated pro-tumor effects, in a manner that was dependent on the concentration of anti-IL-10 antibodies. The CXCR5{sup +} compartment also contained significantly lower frequencies of cytotoxic CD4{sup +} T cells than the CXCR5{sup -} compartment. In conclusion, our investigations discovered a previously unknown pro-tumor role of CXCR5-expressing circulating CD4{sup +} T cells, which assisted the survival and proliferation of primary DLBCL cells through IL-10. - Highlights: • We studied the role of the peripheral Tfh in DLBCL. • Tfh were effective at promoting the proliferation of primary DLBCL tumor cells. • Tfh were effective at inhibiting the apoptosis of primary DLBCL tumor cells. • IL-10 secretion in Tfh was significant elevated in DLBCL. • Neutralization of IL-10 compromised Tfh-mediated pro-tumor effects.

  10. Chronic Lymphocytic Leukemia B-Cell Normal Cellular Counterpart: Clues From a Functional Perspective.

    Science.gov (United States)

    Darwiche, Walaa; Gubler, Brigitte; Marolleau, Jean-Pierre; Ghamlouch, Hussein

    2018-01-01

    Chronic lymphocytic leukemia (CLL) is characterized by the clonal expansion of small mature-looking CD19+ CD23+ CD5+ B-cells that accumulate in the blood, bone marrow, and lymphoid organs. To date, no consensus has been reached concerning the normal cellular counterpart of CLL B-cells and several B-cell types have been proposed. CLL B-cells have remarkable phenotypic and gene expression profile homogeneity. In recent years, the molecular and cellular biology of CLL has been enriched by seminal insights that are leading to a better understanding of the natural history of the disease. Immunophenotypic and molecular approaches (including immunoglobulin heavy-chain variable gene mutational status, transcriptional and epigenetic profiling) comparing the normal B-cell subset and CLL B-cells provide some new insights into the normal cellular counterpart. Functional characteristics (including activation requirements and propensity for plasma cell differentiation) of CLL B-cells have now been investigated for 50 years. B-cell subsets differ substantially in terms of their functional features. Analysis of shared functional characteristics may reveal similarities between normal B-cell subsets and CLL B-cells, allowing speculative assignment of a normal cellular counterpart for CLL B-cells. In this review, we summarize current data regarding peripheral B-cell differentiation and human B-cell subsets and suggest possibilities for a normal cellular counterpart based on the functional characteristics of CLL B-cells. However, a definitive normal cellular counterpart cannot be attributed on the basis of the available data. We discuss the functional characteristics required for a cell to be logically considered to be the normal counterpart of CLL B-cells.

  11. Identification of a B cell-dependent subpopulation of multiple sclerosis by measurements of brain-reactive B cells in the blood.

    Science.gov (United States)

    Kuerten, Stefanie; Pommerschein, Giovanna; Barth, Stefanie K; Hohmann, Christopher; Milles, Bianca; Sammer, Fabian W; Duffy, Cathrina E; Wunsch, Marie; Rovituso, Damiano M; Schroeter, Michael; Addicks, Klaus; Kaiser, Claudia C; Lehmann, Paul V

    2014-01-01

    B cells are increasingly coming into play in the pathogenesis of multiple sclerosis (MS). Here, we screened peripheral blood mononuclear cells (PBMC) from patients with clinically isolated syndrome (CIS), MS, other non-inflammatory neurological, inflammatory neurological or autoimmune diseases, and healthy donors for their B cell reactivity to CNS antigen using the enzyme-linked immunospot technique (ELISPOT) after 96 h of polyclonal stimulation. Our data show that nine of 15 patients with CIS (60.0%) and 53 of 67 patients with definite MS (79.1%) displayed CNS-reactive B cells, compared to none of the control donors. The presence of CNS-reactive B cells in the blood of the majority of patients with MS or at risk to develop MS along with their absence in control subjects suggests that they might be indicative of a B cell-dependent subpopulation of the disease. Copyright © 2014. Published by Elsevier Inc.

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

    Science.gov (United States)

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

    2016-03-16

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

  13. Bruton's tyrosine kinase mediates the synergistic signalling between TLR9 and the B cell receptor by regulating calcium and calmodulin.

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    Elaine F Kenny

    Full Text Available B cells signal through both the B cell receptor (BCR which binds antigens and Toll-like receptors (TLRs including TLR9 which recognises CpG DNA. Activation of TLR9 synergises with BCR signalling when the BCR and TLR9 co-localise within an auto-phagosome-like compartment. Here we report that Bruton's tyrosine kinase (BTK is required for synergistic IL6 production and up-regulation of surface expression of MHC-class-II, CD69 and CD86 in primary murine and human B cells. We show that BTK is essential for co-localisation of the BCR and TLR9 within a potential auto-phagosome-like compartment in the Namalwa human B cell line. Downstream of BTK we find that calcium acting via calmodulin is required for this process. These data provide new insights into the role of BTK, an important target for autoimmune diseases, in B cell activation.

  14. Induction of polyclonal B cell activation and differentiation by the AIDS retrovirus (HTLV-III/LAV)

    International Nuclear Information System (INIS)

    Higgins, S.E.; Schnittman, S.M.; Lane, H.C.; Folks, T.; Koenig, S.; Fauci, A.S.

    1986-01-01

    The immune systems of individuals infected with HTLV-III/LAV are characterized by a profound defect in cellular immunity together with paradoxical polyclonal B cell activation. The present study examined the direct effects of HTLV-III/LAV on B lymphocytes. Peripheral blood B cells from healthy donors were incubated with a variety of HTLV-III/LAV isolates for 1 h and 3 H-thymidine incorporation was measured at multiple time points. Responses ranged from 9000-28,000 cpm and peaked on day 4. This B cell activation was not enhanced by the addition of interleukin-2 to culture, was not synergistic with Staphylococcus aureus Cowan I, was not modulated by the addition of T lymphocytes to culture, and was not associated with B cell transformation. Supernatant Ig could first be detected in virus-activated cultures at day 4, plateaued by day 8, and yielded a mean of 12,500 ng IgG+IgM/ml/50,000 B cells. Thus, HTLV-III/LAV is a potent T cell independent B cell mitogen capable of inducing B cell activation, proliferation, and differentiation comparable in magnitude to that of the most potent B cell activators. This biological property of HTLV-III/LAV may help explain the profound polyclonal B cell activation observed in patients with AIDS and may provide investigators with another probe for investigating the mechanisms of B cell activation

  15. B cell subsets and dysfunction of regulatory B cells in IgG4-related diseases and primary Sjögren’s syndrome: the similarities and differences

    Science.gov (United States)

    2014-01-01

    Introduction IgG4-related disease (IgG4-RD) is a multisystem-involved autoimmune disease. Abnormally activated and differentiated B cells may play important roles. Regulatory B cells (Breg) are newly defined B cell subgroups with immunosuppressive functions. In this study, we investigated the differences of B cell subsets, the expressions of co-stimulatory molecules on B cells, and the function of Breg cells in patients with IgG4-RD, primary Sjögren’s syndrome (pSS) as well as in healthy controls (HC). Methods Newly diagnosed IgG4-RD patients (n = 48) were enrolled, 38 untreated pSS patients and 30 healthy volunteers were recruited as disease and healthy controls. To analyze B cell subsets and B cell activity, PBMCs were surface stained and detected by flow cytometry. The function of Breg cells was tested by coculturing isolated CD19 + CD24hiCD38hi Breg cells with purified CD4 + CD25- T cells. Serum cytokines were measured by ELISA and cytometric bead array. Relationship between clinical data and laboratory findings were analyzed as well. Results Compared with pSS patients and HC, IgG4-RD patients had a lower frequency of peripheral Breg cells. Interestingly, CD19 + CD24-CD38hi B cell subsets were significantly higher in peripheral B cells from IgG4-RD patients than in pSS patients and HC, which correlated with serum IgG4 levels. The expression of BAFF-R and CD40 on B cells was significantly lower in IgG4-RD patients compared with those in pSS patients and HC. Unlike HC, Breg cells from pSS patients lacked suppressive functions. Conclusions B cells in patients with IgG4-RD and pSS display a variety of abnormalities, including disturbed B cell subpopulations, abnormal expression of key signaling molecules, co-stimulatory molecules, and inflammatory cytokines. In addition, a significantly increased B cell subset, CD19 + CD24-CD38hi B cells, may play an important role in the pathogenesis of IgG4-RD. PMID:24887143

  16. HCV Infection and B-Cell Lymphomagenesis

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    Masahiko Ito

    2011-01-01

    Full Text Available Hepatitis C virus (HCV has been recognized as a major cause of chronic liver diseases worldwide. It has been suggested that HCV infects not only hepatocytes but also mononuclear lymphocytes including B cells that express the CD81 molecule, a putative HCV receptor. HCV infection of B cells is the likely cause of B-cell dysregulation disorders such as mixed cryoglobulinemia, rheumatoid factor production, and B-cell lymphoproliferative disorders that may evolve into non-Hodgkin's lymphoma (NHL. Epidemiological data indicate an association between HCV chronic infection and the occurrence of B-cell NHL, suggesting that chronic HCV infection is associated at least in part with B-cell lymphomagenesis. In this paper, we aim to provide an overview of recent literature, including our own, to elucidate a possible role of HCV chronic infection in B-cell lymphomagenesis.

  17. Splenectomy associated changes in IgM memory B cells in an adult spleen registry cohort.

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    Paul U Cameron

    Full Text Available Asplenic patients have a lifelong risk of overwhelming post-splenectomy infection and have been reported to have low numbers of peripheral blood IgM memory B cells. The clinical value of quantitation of memory B cells as an indicator of splenic abnormality or risk of infection has been unclear. To assess changes in B cell sub-populations after splenectomy we studied patients recruited to a spleen registry (n = 591. A subset of 209 adult asplenic or hyposplenic subjects, and normal controls (n = 140 were tested for IgM memory B cells. We also determined a changes in IgM memory B cells with time after splenectomy using the cross-sectional data from patients on the registry and b the kinetics of changes in haematological markers associated with splenectomy(n = 45. Total B cells in splenectomy patients did not differ from controls, but memory B cells, IgM memory B cells and switched B cells were significantly (p<0.001 reduced. The reduction was similar for different indications for splenectomy. Changes of asplenia in routine blood films including presence of Howell-Jolly bodies (HJB, occurred early (median 25 days and splenectomy associated thrombocytosis and lymphocytosis peaked by 50 days. There was a more gradual decrease in IgM memory B cells reaching a stable level within 6 months after splenectomy. IgM memory B cells as proportion of B cells was the best discriminator between splenectomized patients and normal controls and at the optimal cut-off of 4.53, showed a true positive rate of 95% and false positive rate of 20%. In a survey of 152 registry patients stratified by IgM memory B cells around this cut-off there was no association with minor infections and no registry patients experienced OPSI during the study. Despite significant changes after splenectomy, conventional measures of IgM memory cells have limited clinical utility in this population.

  18. Splenectomy Associated Changes in IgM Memory B Cells in an Adult Spleen Registry Cohort

    Science.gov (United States)

    Cameron, Paul U.; Jones, Penelope; Gorniak, Malgorzata; Dunster, Kate; Paul, Eldho; Lewin, Sharon; Woolley, Ian; Spelman, Denis

    2011-01-01

    Asplenic patients have a lifelong risk of overwhelming post-splenectomy infection and have been reported to have low numbers of peripheral blood IgM memory B cells. The clinical value of quantitation of memory B cells as an indicator of splenic abnormality or risk of infection has been unclear. To assess changes in B cell sub-populations after splenectomy we studied patients recruited to a spleen registry (n = 591). A subset of 209 adult asplenic or hyposplenic subjects, and normal controls (n = 140) were tested for IgM memory B cells. We also determined a) changes in IgM memory B cells with time after splenectomy using the cross-sectional data from patients on the registry and b) the kinetics of changes in haematological markers associated with splenectomy(n = 45). Total B cells in splenectomy patients did not differ from controls, but memory B cells, IgM memory B cells and switched B cells were significantly (psplenectomy. Changes of asplenia in routine blood films including presence of Howell-Jolly bodies (HJB), occurred early (median 25 days) and splenectomy associated thrombocytosis and lymphocytosis peaked by 50 days. There was a more gradual decrease in IgM memory B cells reaching a stable level within 6 months after splenectomy. IgM memory B cells as proportion of B cells was the best discriminator between splenectomized patients and normal controls and at the optimal cut-off of 4.53, showed a true positive rate of 95% and false positive rate of 20%. In a survey of 152 registry patients stratified by IgM memory B cells around this cut-off there was no association with minor infections and no registry patients experienced OPSI during the study. Despite significant changes after splenectomy, conventional measures of IgM memory cells have limited clinical utility in this population. PMID:21829713

  19. To B or not to B cells-mediate a healthy start to life.

    Science.gov (United States)

    Nguyen, T G; Ward, C M; Morris, J M

    2013-02-01

    Maternal immune responses during pregnancy are critical in programming the future health of a newborn. The maternal immune system is required to accommodate fetal immune tolerance as well as to provide a protective defence against infections for the immunocompromised mother and her baby during gestation and lactation. Natural immunity and antibody production by maternal B cells play a significant role in providing such immunoprotection. However, aberrations in the B cell compartment as a consequence of maternal autoimmunity can pose serious risks to both the mother and her baby. Despite their potential implication in shaping pregnancy outcomes, the role of B cells in human pregnancy has been poorly studied. This review focuses on the role of B cells and the implications of B cell depletion therapy in pregnancy. It highlights the evidence of an association between aberrant B cell compartment and obstetric conditions. It also alludes to the potential mechanisms that amplify these B cell aberrances and thereby contribute to exacerbation of some maternal autoimmune conditions and poor neonatal outcomes. Clinical and experimental evidence suggests strongly that maternal autoantibodies contribute directly to the pathologies of obstetric and neonatal conditions that have significant implications for the lifelong health of a newborn. The evidence for clinical benefit and safety of B cell depletion therapies in pregnancy is reviewed, and an argument is mounted for further clinical evaluation of B cell-targeted therapies in high-risk pregnancy, with an emphasis on improving neonatal outcomes and prevention of neonatal conditions such as congenital heart block and fetal/neonatal alloimmune thrombocytopenia. © 2012 British Society for Immunology.

  20. IL-15 expression on RA synovial fibroblasts promotes B cell survival.

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    Marta Benito-Miguel

    Full Text Available INTRODUCTION: The purpose of this study was to examine the role of RA Synovial Fibroblast (RASFib IL-15 expression on B cell survival. METHODS: Magnetically sorted peripheral blood memory B cells from 15 healthy subjects were cocultured with RASFib. RESULTS: RASFib constitutively expressed membrane IL-15. Survival of isolated B cells cultured for 6 days, below 5%, was extended in coculture with RASFib to 52+/-8% (p<0.001. IL-15 neutralizing agents but not isotype controls, reduced this rate to 31+/-6% (p<0.05. Interestingly, rhIL-15 had no effect on isolated B cells but significantly increased their survival in coculture with RASFib. In parallel, B cell IL-15R chains were upregulated in cocultures. BAFF and VCAM-1, that are expressed on RASFib, were tested as potential candidates involved in upregulating B cell IL-15R. Culture of B cells in the presence of rhBAFF or rhVCAM-1 resulted in significantly increased survival, together with upregulation of all three IL-15R chains; in parallel, rhIL-15 potentiated the anti-apoptotic effect of BAFF and VCAM-1. Both BAFF and VCAM-1 neutralizing agents downmodulated the effect of RASFib on B cell survival and IL-15R expression. In parallel, rhIL-15 had a lower effect on the survival of B cells cocultured with RASFib in the presence of BAFF or VCAM-1 neutralizing agents. Peripheral blood B cells from 15 early RA patients demonstrated an upregulated IL-15R and increased survival in cocultures. CONCLUSION: IL-15 expression on RASFib significantly contributes to the anti-apoptotic effect of RASFib on B cells. IL-15 action is facilitated by BAFF and VCAM-1 expressed on RASFib, through an upregulation of IL-15R chains.

  1. Related B cell clones populate the meninges and parenchyma of patients with multiple sclerosis.

    Science.gov (United States)

    Lovato, Laura; Willis, Simon N; Rodig, Scott J; Caron, Tyler; Almendinger, Stefany E; Howell, Owain W; Reynolds, Richard; O'Connor, Kevin C; Hafler, David A

    2011-02-01

    In the central nervous system of patients with multiple sclerosis, B cell aggregates populate the meninges, raising the central question as to whether these structures relate to the B cell infiltrates found in parenchymal lesions or instead, represent a separate central nervous system immune compartment. We characterized the repertoires derived from meningeal B cell aggregates and the corresponding parenchymal infiltrates from brain tissue derived primarily from patients with progressive multiple sclerosis. The majority of expanded antigen-experienced B cell clones derived from meningeal aggregates were also present in the parenchyma. We extended this investigation to include 20 grey matter specimens containing meninges, 26 inflammatory plaques, 19 areas of normal appearing white matter and cerebral spinal fluid. Analysis of 1833 B cell receptor heavy chain variable region sequences demonstrated that antigen-experienced clones were consistently shared among these distinct compartments. This study establishes a relationship between extraparenchymal lymphoid tissue and parenchymal infiltrates and defines the arrangement of B cell clones that populate the central nervous system of patients with multiple sclerosis.

  2. Differential radiosensitivity among B cell subpopulations

    International Nuclear Information System (INIS)

    Riggs, J.E.

    1988-01-01

    The selective radiosensitivity of sIgM >> sIgD marginal zone B cells is associated with the selective loss of B cell function. The simultaneous restoration of impaired function and recovery of these cells with time supports this premise. B cell recovery, delayed one week after irradiation, is in progress at two weeks, and virtually complete by three weeks. XID mice reveal similar recovery kinetics although there are fewer recovering cells and these bear reduced levels of Ia. This observation represents additional evidence that xid B cells are distinct from those of normal mice. The simultaneous loss, and concurrent recovery, of sIgM >> sIgD B cells and TI-2 responsiveness in irradiated mice suggests the existence of a unique B cell subpopulation possessing both phenotypes. Additional support for this hypothesis is provided by demonstrating that splenocytes, depleted of IgD + cells adoptively reconstitute this response in XID mice. The peritoneal B cell pool, which, compared to the spleen, consist of increased numbers of sIgM >> sIgD B cells, is shown to be a source of radiosensitive B cells that are TI-2 responsive. These observations represent additional evidence for an association between sIgM >> sIgD B cells and TI-2 responsiveness

  3. ACUTE COMPARTMENT SYNDROME

    African Journals Online (AJOL)

    muscle destruction, muscle fibrosis, contractures and permanent disability and at worst case scenario of amputation (3,4). As reported by Frink et al (3) on their study on acute compartment syndrome it can occur even when there is no fracture. Also general surgeons have reported acute compartment syndrome.

  4. B cell subset distribution is altered in patients with severe periodontitis.

    Science.gov (United States)

    Demoersman, Julien; Pochard, Pierre; Framery, Camille; Simon, Quentin; Boisramé, Sylvie; Soueidan, Assem; Pers, Jacques-Olivier

    2018-01-01

    Several studies have recently highlighted the implication of B cells in physiopathogenesis of periodontal disease by showing that a B cell deficiency leads to improved periodontal parameters. However, the detailed profiles of circulating B cell subsets have not yet been investigated in patients with severe periodontitis (SP). We hypothesised that an abnormal distribution of B cell subsets could be detected in the blood of patients with severe periodontal lesions, as already reported for patients with chronic inflammatory diseases as systemic autoimmune diseases. Fifteen subjects with SP and 13 subjects without periodontitis, according to the definition proposed by the CDC periodontal disease surveillance work group, were enrolled in this pilot observational study. Two flow cytometry panels were designed to analyse the circulating B and B1 cell subset distribution in association with the RANKL expression. A significantly higher percentage of CD27+ memory B cells was observed in patients with SP. Among these CD27+ B cells, the proportion of the switched memory subset was significantly higher. At the same time, human B1 cells, which were previously associated with a regulatory function (CD20+CD69-CD43+CD27+CD11b+), decreased in SP patients. The RANKL expression increased in every B cell subset from the SP patients and was significantly greater in activated B cells than in the subjects without periodontitis. These preliminary results demonstrate the altered distribution of B cells in the context of severe periodontitis. Further investigations with a larger cohort of patients can elucidate if the analysis of the B cell compartment distribution can reflect the periodontal disease activity and be a reliable marker for its prognosis (clinical trial registration number: NCT02833285, B cell functions in periodontitis).

  5. B cell subset distribution is altered in patients with severe periodontitis

    Science.gov (United States)

    Demoersman, Julien; Pochard, Pierre; Framery, Camille; Simon, Quentin; Boisramé, Sylvie; Soueidan, Assem

    2018-01-01

    Several studies have recently highlighted the implication of B cells in physiopathogenesis of periodontal disease by showing that a B cell deficiency leads to improved periodontal parameters. However, the detailed profiles of circulating B cell subsets have not yet been investigated in patients with severe periodontitis (SP). We hypothesised that an abnormal distribution of B cell subsets could be detected in the blood of patients with severe periodontal lesions, as already reported for patients with chronic inflammatory diseases as systemic autoimmune diseases. Fifteen subjects with SP and 13 subjects without periodontitis, according to the definition proposed by the CDC periodontal disease surveillance work group, were enrolled in this pilot observational study. Two flow cytometry panels were designed to analyse the circulating B and B1 cell subset distribution in association with the RANKL expression. A significantly higher percentage of CD27+ memory B cells was observed in patients with SP. Among these CD27+ B cells, the proportion of the switched memory subset was significantly higher. At the same time, human B1 cells, which were previously associated with a regulatory function (CD20+CD69-CD43+CD27+CD11b+), decreased in SP patients. The RANKL expression increased in every B cell subset from the SP patients and was significantly greater in activated B cells than in the subjects without periodontitis. These preliminary results demonstrate the altered distribution of B cells in the context of severe periodontitis. Further investigations with a larger cohort of patients can elucidate if the analysis of the B cell compartment distribution can reflect the periodontal disease activity and be a reliable marker for its prognosis (clinical trial registration number: NCT02833285, B cell functions in periodontitis). PMID:29447240

  6. Characterization of Regulatory B Cells in Graves' Disease and Hashimoto's Thyroiditis

    DEFF Research Database (Denmark)

    Kristensen, Birte; Hegedüs, Laszlo; Lundy, Steven K

    2015-01-01

    A hallmark of regulatory B cells is IL-10 production, hence their designation as IL-10+ B cells. Little is known about the ability of self-antigens to induce IL-10+ B cells in Graves' disease (GD), Hashimoto's thyroiditis (HT), or other autoimmune disease. Here we pulsed purified B cells from 12 HT...... patients, 12 GD patients, and 12 healthy donors with the thyroid self-antigen, thyroglobulin (TG) and added the B cells back to the remaining peripheral blood mononuclear cells (PBMCs). This procedure induced IL-10+ B-cell differentiation in GD. A similar tendency was observed in healthy donors...... and correlated with free T3 levels in GD patients. IL-10+ B cells from both patient groups displayed CD25 or TIM-1 more frequently than did those from healthy donors. B-cell expression of two surface marker combinations previously associated with regulatory B-cell functions, CD24hiCD38hi and CD27+CD43+, did...

  7. A high density of tertiary lymphoid structure B cells in lung tumors is associated with increased CD4+ T cell receptor repertoire clonality.

    Science.gov (United States)

    Zhu, Wei; Germain, Claire; Liu, Zheng; Sebastian, Yinong; Devi, Priyanka; Knockaert, Samantha; Brohawn, Philip; Lehmann, Kim; Damotte, Diane; Validire, Pierre; Yao, Yihong; Valge-Archer, Viia; Hammond, Scott A; Dieu-Nosjean, Marie-Caroline; Higgs, Brandon W

    2015-12-01

    T and B cell receptor (TCR and BCR, respectively) Vβ or immunoglobulin heavy chain complementarity-determining region 3 sequencing allows monitoring of repertoire changes through recognition, clonal expansion, affinity maturation, and T or B cell activation in response to antigen. TCR and BCR repertoire analysis can advance understanding of antitumor immune responses in the tumor microenvironment. TCR and BCR repertoires of sorted CD4 + , CD8 + or CD19 + cells in tumor, non-tumoral distant tissue (NT), and peripheral compartments (blood/draining lymph node [P]) from 47 non-small cell lung cancer (NSCLC) patients (age median = 68 y) were sequenced. The clonotype spectra were assessed among different tissues and correlated with clinical and immunological parameters. In all tissues, CD4 + and CD8 + TCR repertoires had greater clonality relative to CD19 + BCR. CD4 + T cells exhibited greater clonality in NT compared to tumor ( p = 0.002) and P ( p 68). Younger patients exhibited greater CD4 + T cell diversity in P compared to older patients ( p = 0.05), and greater CD4 + T cell clonality in tumor relative to P ( p cell clonality in tumor and P, respectively (both p = 0.05), correlated with high density of tumor-associated tertiary lymphoid structure (TLS) B cells, a biomarker of higher overall survival in NSCLC. Results indicate distinct adaptive immune responses in NSCLC, where peripheral T cell diversity is modulated by age, and tumor T cell clonal expansion is favored by the presence of TLSs in the tumor microenvironment.

  8. B-Cell Hematologic Malignancy Vaccination Registry

    Science.gov (United States)

    2017-12-29

    Monoclonal Gammopathy of Undetermined Significance; Multiple Myeloma; Waldenstrom Macroglobulinemia; Lymphocytosis; Lymphoma, Non-Hodgkin; B-Cell Chronic Lymphocytic Leukemia; Hematological Malignancies

  9. Transcriptional profiling of PBMCs unravels B cell mediated immunopathogenic imprints of HCV vasculitis.

    Science.gov (United States)

    Comstock, Emily; Kim, Cheol-Woo; Murphy, Alison; Emmanuel, Benjamin; Zhang, Xi; Sneller, Michael; Poonia, Bhawna; Kottilil, Shyamasundaran

    2017-01-01

    B cell depletion therapy using rituximab has been shown to be effective in achieving remission in patients with HCV-mixed cryoglobulinemic (MC) vasculitis. Previously, we have demonstrated abnormalities in peripheral immune cells involving neutrophils, chemotaxis, and innate immune activation among patients with HCV-MC vasculitis when compared to HCV patients without vasculitis. In this study, we evaluated the effect of B cell depletion therapy on transcriptional profiles of peripheral blood mononuclear cells before and after riruximab therapy, in order to unravel the pathogenic mechanism involved in HCV-MC vasculitis induced by abnormal B cell proliferation. DNA microarray analysis was performed using RNA from PBMCs from seven patients with HCV-MC vasculitis and seven normal volunteers. DNA was hybridized to Affymetrix U133A chips. After normalization, differentially expressed gene list with treatment was generated using partitional clustering. RT-PCR, flow cytometry, and enzyme immunoassay (EIA) was used to validate DNA microarray findings. Differentially expressed genes included B cells and non-B cell genes. Validation of genes using purified cell subsets demonstrated distinct effect of B cell depletion therapy on non-B cells, such as monocytes, T cells, and NK cells. Notably, B lymphocyte stimulator (BLyS) levels were persistently elevated in patients who subsequently relapsed. In conclusion, pathogenesis of HCV-MC vasculitis is mediated by abnormal proliferation of B cells, driven by BLyS, leading to significant effects on non-B cells in mediating symptomatology. Future therapeutics using a combination approach of B cell depletion and proliferation may be desired to achieve long-term remission.

  10. Most B cells in non-lymphoid tissues are naïve.

    Science.gov (United States)

    Inman, Charlotte F; Murray, Tamsin Zangerle; Bailey, Mick; Cose, Stephen

    2012-02-01

    The current view of lymphocyte migration states that naïve lymphocytes re-circulate between the blood and the lymph via the lymph nodes, but are not able to access non-lymphoid tissues. We examined B lymphocytes in peripheral tissues and found that the majority were phenotypically similar to naïve B cells in lymphoid tissues and were located within the parenchyma, not associated with blood vessels. The mutation rate within the Vh region of these cells was substantially less than the rate attributed to somatic hypermutation and was identical to that observed in naïve B cells isolated from the lymph nodes, showing the presence of naïve B cells in the non-lymphoid organs. Further, using FTY720-treated mice, we showed that naïve B cells migrate through the peripheral tissues and, using pertussis toxin, that the entry of B cells was not controlled by chemokine-mediated signalling events. Overall, these results show that naïve B lymphocytes constitute the majority of the total B-cell population in non-lymphoid tissues and suggest that these cells may re-circulate through the periphery as part of their normal migration pathway. This has implications for the current view of the role of naïve B cells in priming and tolerance.

  11. Chronic Exposure to Malaria Is Associated with Inhibitory and Activation Markers on Atypical Memory B Cells and Marginal Zone-Like B Cells

    Directory of Open Access Journals (Sweden)

    Itziar Ubillos

    2017-08-01

    Full Text Available In persistent infections that are accompanied by chronic immune activation, such as human immunodeficiency virus, hepatitis C virus, and malaria, there is an increased frequency of a phenotypically distinct subset of memory B cells lacking the classic memory marker CD27 and showing a reduced capacity to produce antibodies. However, critical knowledge gaps remain on specific B cell changes and immune adaptation in chronic infections. We hypothesized that expansion of atypical memory B cells (aMBCs and reduction of activated peripheral marginal zone (MZ-like B cells in constantly exposed individuals might be accompanied by phenotypic changes that would confer a tolerogenic profile, helping to establish tolerance to infections. To better understand malaria-associated phenotypic abnormalities on B cells, we analyzed peripheral blood mononuclear cells from 55 pregnant women living in a malaria-endemic area of Papua Nueva Guinea and 9 Spanish malaria-naïve individuals using four 11-color flow cytometry panels. We assessed the expression of markers of B cell specificity (IgG and IgM, activation (CD40, CD80, CD86, b220, TACI, and CD150, inhibition (PD1, CD95, and CD71, and migration (CCR3, CXCR3, and CD62l. We found higher frequencies of active and resting aMBC and marked reduction of MZ-like B cells, although changes in absolute cell counts could not be assessed. Highly exposed women had higher PD1+-, CD95+-, CD40+-, CD71+-, and CD80+-activated aMBC frequencies than non-exposed subjects. Malaria exposure increased frequencies of b220 and proapoptotic markers PD1 and CD95, and decreased expression of the activation marker TACI on MZ-like B cells. The increased frequencies of inhibitory and apoptotic markers on activated aMBCs and MZ-like B cells in malaria-exposed adults suggest an immune-homeostatic mechanism for maintaining B cell development and function while simultaneously downregulating hyperreactive B cells. This mechanism would keep the B cell

  12. The nanoscale spatial organization of B-cell receptors on immunoglobulin M- and G-expressing human B-cells.

    Science.gov (United States)

    Lee, Jinmin; Sengupta, Prabuddha; Brzostowski, Joseph; Lippincott-Schwartz, Jennifer; Pierce, Susan K

    2017-02-15

    B-cell activation is initiated by the binding of antigen to the B-cell receptor (BCR). Here we used dSTORM superresolution imaging to characterize the nanoscale spatial organization of immunoglobulin M (IgM) and IgG BCRs on the surfaces of resting and antigen--activated human peripheral blood B-cells. We provide insights into both the fundamental process of antigen-driven BCR clustering and differences in the spatial organization of IgM and IgG BCRs that may contribute to the characteristic differences in the responses of naive and memory B-cells to antigen. We provide evidence that although both IgM and IgG BCRs reside in highly heterogeneous protein islands that vary in size and number of BCR single-molecule localizations, both resting and activated B-cells intrinsically maintain a high -frequency of single isolated BCR localizations, which likely represent BCR monomers. IgG BCRs are more clustered than IgM BCRs on resting cells and form larger protein islands after antigen activation. Small, dense BCR clusters likely formed via protein-protein interactions are present on the surface of resting cells, and antigen activation induces these to come together to form less dense, larger islands, a process likely governed, at least in part, by protein-lipid interactions. © 2017 Lee, Sengupta, et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  13. Analysis of antigen-specific B-cell memory directly ex vivo.

    Science.gov (United States)

    McHeyzer-Williams, Louise J; McHeyzer-Williams, Michael G

    2004-01-01

    Helper T-cell-regulated B-cell memory develops in response to initial antigen priming as a cellular product of the germinal center (GC) reaction. On antigen recall, memory response precursors expand rapidly with exaggerated differentiation into plasma cells to produce the high-titer, high-affinity antibody(Ab) that typifies the memory B-cell response in vivo. We have devised a high-resolution flow cytometric strategy to quantify the emergence and maintenance of antigen-specific memory B cells directly ex vivo. Extended cell surface phenotype establishes a level of cellular diversity not previously appreciated for the memory B-cell compartment. Using an "exclusion transfer" strategy, we ascertain the capacity of two distinct memory B-cell populations to transfer antigen-specific memory into naive adoptive hosts. Finally, we sequence expressed messenger ribonucleic acid (mRNA) from single cells within the population to estimate the level of somatic hypermutation as the best molecular indicator of B-cell memory. In this chapter, we describe the methods used in each of these four sections that serve to provide high-resolution quantification of antigen-specific B-cell memory responses directly ex vivo.

  14. Morphologic and Functional Effects of Gamma Secretase Inhibition on Splenic Marginal Zone B Cells

    Directory of Open Access Journals (Sweden)

    Maria Cristina de Vera Mudry

    2012-01-01

    Full Text Available The γ-secretase complex is a promising target in Alzheimer’s disease because of its role in the amyloidogenic processing of β-amyloid precursor protein. This enzyme also catalyzes the cleavage of Notch receptor, resulting in the nuclear translocation of intracellular Notch where it modulates gene transcription. Notch signaling is essential in cell fate decisions during embryogenesis, neuronal differentiation, hematopoiesis, and development of T and B cells, including splenic marginal zone (MZ B cells. This B cell compartment participates in the early phases of the immune response to blood-borne bacteria and viruses. Chronic treatment with the oral γ-secretase inhibitor RO4929097 resulted in dose-dependent decreased cellularity (atrophy of the MZ of rats and mice. Significant decreases in relative MZ B-cell numbers of RO4929097-treated animals were confirmed by flow cytometry. Numbers of MZ B cells reverted to normal after a sufficient RO4929097-free recovery period. Functional characterization of the immune response in relation to RO4929097-related MZ B cell decrease was assessed in mice vaccinated with inactivated vesicular stomatitis virus (VSV. Compared with the immunosuppressant cyclosporin A, RO4929097 caused only mild and reversible delayed early neutralizing IgM and IgG responses to VSV. Thus, the functional consequence of MZ B cell decrease on host defense is comparatively mild.

  15. Morphologic and Functional Effects of Gamma Secretase Inhibition on Splenic Marginal Zone B Cells

    Science.gov (United States)

    de Vera Mudry, Maria Cristina; Regenass-Lechner, Franziska; Ozmen, Laurence; Altmann, Bernd; Festag, Matthias; Singer, Thomas; Müller, Lutz; Jacobsen, Helmut; Flohr, Alexander

    2012-01-01

    The γ-secretase complex is a promising target in Alzheimer's disease because of its role in the amyloidogenic processing of β-amyloid precursor protein. This enzyme also catalyzes the cleavage of Notch receptor, resulting in the nuclear translocation of intracellular Notch where it modulates gene transcription. Notch signaling is essential in cell fate decisions during embryogenesis, neuronal differentiation, hematopoiesis, and development of T and B cells, including splenic marginal zone (MZ) B cells. This B cell compartment participates in the early phases of the immune response to blood-borne bacteria and viruses. Chronic treatment with the oral γ-secretase inhibitor RO4929097 resulted in dose-dependent decreased cellularity (atrophy) of the MZ of rats and mice. Significant decreases in relative MZ B-cell numbers of RO4929097-treated animals were confirmed by flow cytometry. Numbers of MZ B cells reverted to normal after a sufficient RO4929097-free recovery period. Functional characterization of the immune response in relation to RO4929097-related MZ B cell decrease was assessed in mice vaccinated with inactivated vesicular stomatitis virus (VSV). Compared with the immunosuppressant cyclosporin A, RO4929097 caused only mild and reversible delayed early neutralizing IgM and IgG responses to VSV. Thus, the functional consequence of MZ B cell decrease on host defense is comparatively mild. PMID:23316412

  16. Abdominal Compartment Syndrome

    Directory of Open Access Journals (Sweden)

    Pınar Zeyneloğlu

    2015-04-01

    Full Text Available Intraabdominal hypertension and Abdominal compartment syndrome are causes of morbidity and mortality in critical care patients. Timely diagnosis and treatment may improve organ functions. Intra-abdominal pressure monitoring is vital during evaluation of the patients and in the management algorithms. The incidence, definition and risk factors, clinical presentation, diagnosis and management of intraabdominal hypertension and Abdominal compartment syndrome were reviewed here.

  17. B cells and B cell products-helping to restore cellular immunity?

    OpenAIRE

    Cascalho, Marilia; Platt, Jeffrey L.

    2006-01-01

    T cells that provide vital protection against tumors, viruses and intracellular bacteria are thought to develop independently of B cells. However, recent discoveries suggest that development of T cells depends on B cells. One way B cells promote T cell development is by providing diverse peptides that may promote positive selection of thymocytes. Diverse peptides and B cells help in diversification of the T cell receptor repertoire and may decrease cross-reactivity in the mature T cell compar...

  18. Naive and effector B-cell subtypes are increased in chronic rhinosinusitis with polyps.

    Science.gov (United States)

    Miljkovic, Dijana; Psaltis, Alkis; Wormald, Peter-John; Vreugde, Sarah

    2018-01-01

    Recent studies demonstrated that B cells and their chemoattractants are elevated in the nasal mucosa of patients with chronic rhinosinusitis (CRS) with nasal polyposis (CRSwNP). However, the presence of naive B cells and of plasmablasts and memory B-cell subsets in the mucosa and periphery of the same patient with CRS is yet to be characterized. Here we sought to quantify naive, plasmablasts, and memory B cells in mucosal tissue and peripheral blood of patients with CRSwNP, patients with CRS without nasal polyps (CRSsNP), and control patients. Polyps, mucosa, and peripheral blood samples were prospectively collected from the patients with CRS and from the non-CRS controls. We used flow cytometry to distinguish among naive, plasmablast, and memory B cells in sinus tissue and peripheral blood. A total of 45 patients were recruited for the study. The patients with CRSwNP had significantly increased mucosal B-cell numbers versus the controls (3.39 ± 4.05% versus 0.39 ± 1.05% of live cells; p Kruskal-Wallis test), which included naive B cells (0.61 ± 0.94 versus 0.11 ± 0.24% of live cells; p Kruskal-Wallis test), plasmablasts (0.06 ± 0.26 versus 0.00 ± 0.00% of live cells; p Kruskal-Wallis test), and memory B cells (0.62 ± 1.26 versus 0.05 ± 0.15% of live cells; p Kruskal-Wallis test). Our study identified increased frequencies of different B-cell subtypes in the mucosa of patients with CRSwNP but not in the peripheral blood. We also found that patients with CRSwNP had significantly increased B-cell subtypes compared with the patients with CRSsNP and the controls. These results implied a potential role for mucosal B cells in the ongoing inflammation in patients with CRSwNP.

  19. CD3-positive B cells: a storage-dependent phenomenon.

    Directory of Open Access Journals (Sweden)

    Angela Nagel

    Full Text Available The majority of clinical studies requires extensive management of human specimen including e.g. overnight shipping of blood samples in order to convey the samples in a central laboratory or to simultaneously analyze large numbers of patients. Storage of blood samples for periods of time before in vitro/ex vivo testing is known to influence the antigen expression on the surface of lymphocytes. In this context, the present results show for the first time that the T cell antigen CD3 can be substantially detected on the surface of human B cells after ex vivo storage and that the degree of this phenomenon critically depends on temperature and duration after blood withdrawal. The appearance of CD3 on the B cell surface seems to be a result of contact-dependent antigen exchange between T and B lymphocytes and is not attributed to endogenous production by B cells. Since cellular subsets are often classified by phenotypic analyses, our results indicate that ex vivo cellular classification in peripheral blood might result in misleading interpretations. Therefore, in order to obtain results reflecting the in vivo situation, it is suggested to minimize times of ex vivo blood storage after isolation of PBMC. Moreover, to enable reproducibility of results between different research groups and multicenter studies, we would emphasize the necessity to specify and standardize the storage conditions, which might be the basis of particular findings.

  20. Peripheral neuropathy

    Science.gov (United States)

    ... peripheral; Neuritis - peripheral; Nerve disease; Polyneuropathy; Chronic pain - peripheral neuropathy ... Philadelphia, PA: Elsevier; 2016:chap 107. Shy ME. Peripheral neuropathies. In: Goldman L, Schafer AI, eds. Goldman's Cecil ...

  1. B Cell Tolerance in Health and Disease

    Directory of Open Access Journals (Sweden)

    Murali Gururajan

    2014-02-01

    Full Text Available B lymphocyte receptors are generated randomly during the bone marrow developmental phase of B cells. Hence, the B cell repertoire consists of both self and foreign antigen specificities necessitating specific tolerance mechanisms to eliminate self-reactive B cells. This review summarizes the major mechanisms of B cell tolerance, which include clonal deletion, anergy and receptor editing. In the bone marrow presentation of antigen in membrane bound form is more effective than soluble form and the role of dendritic cells in this process is discussed. Toll like receptor derived signals affect activation of B cells by certain ligands such as nucleic acids and have been shown to play crucial roles in the development of autoimmunity in several animal models. In the periphery availability of BAFF, a B cell survival factor plays a critical role in the survival of self-reactive B cells. Antibodies against BAFF have been found to be effective therapeutic agents in lupus like autoimmune diseases. Recent developments are targeting anergy to control the growth of chronic lymphocytic leukemia cells.

  2. B Cells and Autoantibodies in Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Anne-Katrin Pröbstel

    2015-07-01

    Full Text Available While over the past decades T cells have been considered key players in the pathogenesis of multiple sclerosis (MS, it has only recently become evident that B cells have a major contributing role. Our understanding of the role of B cells has evolved substantially following the clinical success of B cell-targeting therapies and increasing experimental evidence for significant B cell involvement. Rather than mere antibody-producing cells, it is becoming clear that they are team players with the capacity to prime and regulate T cells, and function both as pro- and anti-inflammatory mediators. However, despite tremendous efforts, the target antigen(s of B cells in MS have yet to be identified. The first part of this review summarizes the clinical evidence and results from animal studies pointing to the relevance of B cells in the pathogenesis of MS. The second part gives an overview of the currently known potential autoantigen targets. The third part recapitulates and critically appraises the currently available B cell-directed therapies.

  3. Ikaros limits follicular B cell activation by regulating B cell receptor signaling pathways

    International Nuclear Information System (INIS)

    Heizmann, Beate; Sellars, MacLean; Macias-Garcia, Alejandra; Chan, Susan; Kastner, Philippe

    2016-01-01

    The Ikaros transcription factor is essential for early B cell development, but its effect on mature B cells is debated. We show that Ikaros is required to limit the response of naive splenic B cells to B cell receptor signals. Ikaros deficient follicular B cells grow larger and enter cell cycle faster after anti-IgM stimulation. Unstimulated mutant B cells show deregulation of positive and negative regulators of signal transduction at the mRNA level, and constitutive phosphorylation of ERK, p38, SYK, BTK, AKT and LYN. Stimulation results in enhanced and prolonged ERK and p38 phosphorylation, followed by hyper-proliferation. Pharmacological inhibition of ERK and p38 abrogates the increased proliferative response of Ikaros deficient cells. These results suggest that Ikaros functions as a negative regulator of follicular B cell activation.

  4. Ikaros limits follicular B cell activation by regulating B cell receptor signaling pathways

    Energy Technology Data Exchange (ETDEWEB)

    Heizmann, Beate [Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964, CNRS UMR 7104, Université de Strasbourg, 67404 Illkirch (France); Sellars, MacLean [Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964, CNRS UMR 7104, Université de Strasbourg, 67404 Illkirch (France); David Geffen School of Medicine at UCLA, Los Angeles, CA 90095 (United States); Macias-Garcia, Alejandra [Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964, CNRS UMR 7104, Université de Strasbourg, 67404 Illkirch (France); Institute for Medical Engineering and Science at MIT, Cambridge, MA 02139 (United States); Chan, Susan, E-mail: scpk@igbmc.fr [Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964, CNRS UMR 7104, Université de Strasbourg, 67404 Illkirch (France); Kastner, Philippe, E-mail: scpk@igbmc.fr [Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964, CNRS UMR 7104, Université de Strasbourg, 67404 Illkirch (France); Faculté de Médecine, Université de Strasbourg, Strasbourg (France)

    2016-02-12

    The Ikaros transcription factor is essential for early B cell development, but its effect on mature B cells is debated. We show that Ikaros is required to limit the response of naive splenic B cells to B cell receptor signals. Ikaros deficient follicular B cells grow larger and enter cell cycle faster after anti-IgM stimulation. Unstimulated mutant B cells show deregulation of positive and negative regulators of signal transduction at the mRNA level, and constitutive phosphorylation of ERK, p38, SYK, BTK, AKT and LYN. Stimulation results in enhanced and prolonged ERK and p38 phosphorylation, followed by hyper-proliferation. Pharmacological inhibition of ERK and p38 abrogates the increased proliferative response of Ikaros deficient cells. These results suggest that Ikaros functions as a negative regulator of follicular B cell activation.

  5. HIV-Specific B Cell Frequency Correlates with Neutralization Breadth in Patients Naturally Controlling HIV-Infection

    Directory of Open Access Journals (Sweden)

    Angeline Rouers

    2017-07-01

    Full Text Available HIV-specific broadly neutralizing antibodies (bnAbs have been isolated from patients with high viremia but also from HIV controllers that repress HIV-1 replication. In these elite controllers (ECs, multiple parameters contribute to viral suppression, including genetic factors and immune responses. Defining the immune correlates associated with the generation of bnAbs may help in designing efficient immunotherapies. In this study, in ECs either positive or negative for the HLA-B*57 protective allele, in treated HIV-infected and HIV-negative individuals, we characterized memory B cell compartments and HIV-specific memory B cells responses using flow cytometry and ELISPOT. ECs preserved their memory B cell compartments and in contrast to treated patients, maintained detectable HIV-specific memory B cell responses. All ECs presented IgG1+ HIV-specific memory B cells but some individuals also preserved IgG2+ or IgG3+ responses. Importantly, we also analyzed the capacity of sera from ECs to neutralize a panel of HIV strains including transmitted/founder virus. 29% and 21% of HLA-B*57+ and HLA-B*57− ECs, respectively, neutralized at least 40% of the viral strains tested. Remarkably, in HLA-B*57+ ECs the frequency of HIV-Env-specific memory B cells correlated positively with the neutralization breadth suggesting that preservation of HIV-specific memory B cells might contribute to the neutralizing responses in these patients.

  6. Lipid rafts and B cell signaling.

    Science.gov (United States)

    Gupta, Neetu; DeFranco, Anthony L

    2007-10-01

    B cells comprise an essential component of the humoral immune system. They are equipped with the unique ability to synthesize and secrete pathogen-neutralizing antibodies, and share with professional antigen presenting cells the ability to internalize foreign antigens, and process them for presentation to helper T cells. Recent evidence indicates that specialized cholesterol- and glycosphingolipid-rich microdomains in the plasma membrane commonly referred to as lipid rafts, serve to compartmentalize key signaling molecules during the different stages of B cell activation including B cell antigen receptor (BCR)-initiated signal transduction, endocytosis of BCR-antigen complexes, loading of antigenic peptides onto MHC class II molecules, MHC-II associated antigen presentation to helper T cells, and receipt of helper signals via the CD40 receptor. Here we review the recent literature arguing for a role of lipid rafts in the spatial organization of B cell function.

  7. B-cell waste classification sampling plan

    International Nuclear Information System (INIS)

    HOBART, R.L.

    1999-01-01

    This report documents the methods used to collect samples and analyze data necessary to verify and/or determine the radionuclide content of the 324 Facility B-Cell decontamination and decommissioning waste stream

  8. Loss of circulating CD4 T cells with B cell helper function during chronic HIV infection.

    Directory of Open Access Journals (Sweden)

    Kristin L Boswell

    2014-01-01

    Full Text Available The interaction between follicular T helper cells (TFH and B cells in the lymph nodes and spleen has a major impact on the development of antigen-specific B cell responses during infection or vaccination. Recent studies described a functional equivalent of these cells among circulating CD4 T cells, referred to as peripheral TFH cells. Here, we characterize the phenotype and in vitro B cell helper activity of peripheral TFH populations, as well as the effect of HIV infection on these populations. In co-culture experiments we confirmed CXCR5+ cells from HIV-uninfected donors provide help to B cells and more specifically, we identified a CCR7(highCXCR5(highCCR6(highPD-1(high CD4 T cell population that secretes IL-21 and enhances isotype-switched immunoglobulin production. This population is significantly decreased in treatment-naïve, HIV-infected individuals and can be recovered after anti-retroviral therapy. We found impaired immunoglobulin production in co-cultures from HIV-infected individuals and found no correlation between the frequency of peripheral TFH cells and memory B cells, or with neutralization activity in untreated HIV infection in our cohort. Furthermore, we found that within the peripheral TFH population, the expression level of TFH-associated genes more closely resembles a memory, non-TFH population, as opposed to a TFH population. Overall, our data identify a heterogeneous population of circulating CD4 T cells that provides in vitro help to B cells, and challenges the origin of these cells as memory TFH cells.

  9. An increase in circulating B cell-activating factor in childhood-onset ocular myasthenia gravis.

    Science.gov (United States)

    Motobayashi, Mitsuo; Inaba, Yuji; Nishimura, Takafumi; Kobayashi, Norimoto; Nakazawa, Yozo; Koike, Kenichi

    2015-04-01

    Myasthenia gravis is a B cell-mediated autoimmune disorder. The pathophysiology of childhood-onset ocular myasthenia gravis remains unclear. We investigated serum B cell-activating factor levels and other immunological parameters in child patients with ocular myasthenia gravis. Blood samples were obtained from 9 children with ocular myasthenia gravis and 20 age-matched controls. We assayed serum concentrations of B cell-activating factor, anti-acetylcholine receptor antibody titers, 7 types of cytokines (interleukins-2, -4, -6, -10, and -17A; interferon-γ; tumor necrosis factor-α) as well as the percentages of peripheral blood CD4+, CD8+, and CD19+ cells. Serum B cell-activating factor levels were significantly higher before immunosuppressive therapy in patients with childhood-onset ocular myasthenia gravis than in controls and decreased after immunosuppressive therapy. A significant positive correlation was observed between serum B cell-activating factor levels and anti-acetylcholine receptor antibody titers in patients with myasthenia gravis. Serum B cell-activating factor concentrations did not correlate with the percentages of CD4+, CD8+, and CD19+ cells or the CD4+/CD8+ ratio. No significant differences were observed in the levels of the 7 different types of cytokines examined, including interleukin-17A, between preimmunosuppressive therapy myasthenia gravis patients and controls. Circulating B cell-activating factor may play a key role in the pathophysiology of childhood-onset ocular myasthenia gravis. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Longitudinal dynamics of the HIV-specific B cell response during intermittent treatment of primary HIV infection.

    Directory of Open Access Journals (Sweden)

    Godelieve J de Bree

    Full Text Available Neutralizing antibodies develop in natural HIV-1 infection. Their development often takes several years and may rely on chronic virus exposure. At the same time recent studies show that treatment early in infection may provide opportunities for immune preservation. However, it is unknown how intermittent treatment in early infection affects development of the humoral immune response over time. We investigate the effect of cART in early HIV infection on the properties of the memory B cell compartment following 6 months of cART or in the absence of treatment. The patients included participated in the Primo-SHM trial where patients with an early HIV-1 infection were randomized to no treatment or treatment for 24 or 60 weeks.Primo-SHM trial patients selected for the present study were untreated (n = 23 or treated for 24 weeks (n = 24. Here we investigate memory B cell properties at viral set-point and at a late time point (respectively median 54 and 73 weeks before (re-initiation of treatment.At viral set-point, the memory B cell compartment in treated patients demonstrated significantly lower fractions of antigen-primed, activated, memory B cells (p = 0.006. In contrast to untreated patients, in treated patients the humoral HIV-specific response reached a set point over time. At a transcriptional level, sets of genes that showed enhanced expression in memory B cells at viral setpoint in untreated patients, conversely showed rapid increase of expression of the same genes in treated patients at the late time point.These data suggest that, although the memory B cell compartment is phenotypically preserved until viral setpoint after treatment interruption, the development of the HIV-specific antibody response may benefit from exposure to HIV. The effect of viral exposure on B cell properties is also reflected by longitudinal changes in transcriptional profile in memory B cells over time in early treated patients.

  11. Cancer Stem Cells of Differentiated B-Cell Malignancies: Models and Consequences

    International Nuclear Information System (INIS)

    Gross, Emilie; Quillet-Mary, Anne; Ysebaert, Loic; Laurent, Guy; Fournie, Jean-Jacques

    2011-01-01

    The concept of cancer stem cells has revolutionized our current vision of cancer development and was validated in solid tumors and cancers of the primitive hematopoietic compartment. Proof of the principle is still lacking, however, in malignancies of differentiated B-cells. We review here the current literature, which nevertheless suggests hierarchical organizations of the tumor clone for mostly incurable B-cell cancers such as multiple myeloma, lymphomas and B-chronic lymphocytic leukemia. We propose two models accounting for cancer stem cells in these contexts: a “top-to-bottom” clonal hierarchy from memory B-cells and a “bottom-to-top” model of clonal reprogramming. Selection pressure on the growing tumor can drive such reprogramming and increase its genetic diversity

  12. Activation of autoreactive B cells by endogenous TLR7 and TLR3 RNA ligands.

    Science.gov (United States)

    Green, Nathaniel M; Moody, Krishna-Sulayman; Debatis, Michelle; Marshak-Rothstein, Ann

    2012-11-16

    The key step in the activation of autoreactive B cells is the internalization of nucleic acid containing ligands and delivery of these ligands to the Toll-like Receptor (TLR) containing endolysosomal compartment. Ribonucleoproteins represent a large fraction of autoantigens in systemic autoimmune diseases. Here we demonstrate that many uridine-rich mammalian RNA sequences associated with common autoantigens effectively activate autoreactive B cells. Priming with type I IFN increased the magnitude of activation, and the range of which RNAs were stimulatory. A subset of RNAs that contain a high degree of self-complementarity also activated B cells through TLR3. For the RNA sequences that activated predominantly through TLR7, the activation is proportional to uridine-content, and more precisely defined by the frequency of specific uridine-containing motifs. These results identify parameters that define specific mammalian RNAs as ligands for TLRs.

  13. Cancer Stem Cells of Differentiated B-Cell Malignancies: Models and Consequences

    Directory of Open Access Journals (Sweden)

    Jean-Jacques Fournie

    2011-03-01

    Full Text Available The concept of cancer stem cells has revolutionized our current vision of cancer development and was validated in solid tumors and cancers of the primitive hematopoietic compartment. Proof of the principle is still lacking, however, in malignancies of differentiated B-cells. We review here the current literature, which nevertheless suggests hierarchical organizations of the tumor clone for mostly incurable B-cell cancers such as multiple myeloma, lymphomas and B-chronic lymphocytic leukemia. We propose two models accounting for cancer stem cells in these contexts: a “top-to-bottom” clonal hierarchy from memory B-cells and a “bottom-to-top” model of clonal reprogramming. Selection pressure on the growing tumor can drive such reprogramming and increase its genetic diversity.

  14. The double bromodomain protein Brd2 promotes B cell expansion and mitogenesis.

    Science.gov (United States)

    Belkina, Anna C; Blanton, Wanda P; Nikolajczyk, Barbara S; Denis, Gerald V

    2014-03-01

    Bromodomain-containing transcriptional regulators represent new epigenetic targets in different hematologic malignancies. However, bromodomain-mediated mechanisms that couple histone acetylation to transcription in lymphopoiesis and govern mature lymphocyte mitogenesis are poorly understood. Brd2, a transcriptional coregulator that contains dual bromodomains and an extraterminal domain (the BET family), couples chromatin to cell-cycle progression. We reported previously the first functional characterization of a BET protein as an effector of mammalian mitogenic signal transduction: Eμ-Brd2 Tg mice develop "activated B cell" diffuse large B cell lymphoma. No other animal models exist for genetic or lentiviral expression of BET proteins, hampering testing of novel anti-BET anticancer drugs, such as JQ1. We transduced HSCs with Brd2 lentivirus and reconstituted recipient mice to test the hypothesis that Brd2 regulates hematopoiesis in BM and mitogenesis in the periphery. Forced expression of Brd2 provides an expansion advantage to the donor-derived B cell compartment in BM and increases mature B cell mitogenic responsiveness in vitro. Brd2 binds the cyclin A promoter in B cells, shown by ChIP, and increases cyclin A mRNA and protein levels, and S-phase progression in vitro in mitogen-stimulated primary B cells, but not T cells, reinforcing results from Eμ-Brd2 mice. The small molecule BET inhibitor JQ1 reduces B cell mitogenesis, consistent with the interpretation that BET inhibitors are antiproliferative. Brd2-specific knockdown experiments show that Brd2 is also required for hematopoiesis. We conclude that Brd2 plays a critical, independent role in regulation of mitogenic response genes, particularly cyclin A, in B cells.

  15. APS, an adaptor molecule containing PH and SH2 domains, has a negative regulatory role in B cell proliferation

    International Nuclear Information System (INIS)

    Iseki, Masanori; Kubo-Akashi, Chiyomi; Kwon, Sang-Mo; Yamaguchi, Akiko; Takatsu, Kiyoshi; Takaki, Satoshi

    2005-01-01

    Adaptor molecule containing PH and SH2 domains (APS) is an intracellular adaptor protein that forms part of an adaptor family along with Lnk and SH2-B. APS transcripts are expressed in various tissues including brain, kidney, and muscle, as well as in splenic B cells but not in T cells. We investigated the functions of APS in B cell development and activation by generating APS-transgenic (APS-Tg) mice that overexpressed APS in lymphocytes. The number of B-1 cells in the peritoneal cavity was reduced in APS-Tg mice, as were B-2 cells in the spleen. B cell development in the bone marrow was partially impaired at the transition stage from proliferating large pre-B to small pre-B cells. B cell proliferation induced by B cell receptor (BCR) crosslinking but not by other B cell mitogens was also impaired in APS-Tg mice. APS co-localized with BCR complexes and filamentous actin in activated APS-Tg B cells. Thus, APS appears to play novel negative regulatory roles in BCR signaling, actin reorganization pathways, and control of compartment sizes of B-lineage cells

  16. Epidermotropic presentation by splenic B-cell lymphoma: The importance of clinical-pathologic correlation.

    Science.gov (United States)

    Hedayat, Amin A; Carter, Joi B; Lansigan, Frederick; LeBlanc, Robert E

    2018-04-01

    There are exceedingly rare reports of patients with epidermotropic B-cell lymphomas. A subset presented with intermittent, variably pruritic papular eruptions and involvement of their spleens, peripheral blood and bone marrow at the time of diagnosis. Furthermore, some experienced an indolent course despite dissemination of their lymphomas. We report a 66-year-old woman with a 12-year history of intermittent eruptions of non-pruritic, salmon-colored papules on her torso and proximal extremities that occurred in winter and resolved with outdoor activity in spring. Skin biopsy revealed an epidermotropic B-cell lymphoma with a non-specific B-cell phenotype and heavy chain class switching with IgG expression. On workup, our patient exhibited mild splenomegaly and low-level involvement of her peripheral blood and bone marrow by a kappa-restricted B-cell population. A splenic B-cell lymphoma was diagnosed. Considering her longstanding history and absences of cytopenias, our patient has been followed without splenectomy or systemic therapy. Furthermore, the papules have responded dramatically to narrowband UVB. Our case and a review of similar rare reports aim to raise awareness among dermatopathologists and dermatologists of a clinically distinct and indolent subset of epidermotropic splenic lymphomas with characteristic clinical and histologic findings. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. IL-10-produced by human transitional B-cells down-regulates CD86 expression on B-cells leading to inhibition of CD4+T-cell responses.

    Science.gov (United States)

    Nova-Lamperti, Estefania; Fanelli, Giorgia; Becker, Pablo D; Chana, Prabhjoat; Elgueta, Raul; Dodd, Philippa C; Lord, Graham M; Lombardi, Giovanna; Hernandez-Fuentes, Maria P

    2016-01-22

    A novel subset of human regulatory B-cells has recently been described. They arise from within the transitional B-cell subpopulation and are characterised by the production of IL-10. They appear to be of significant importance in regulating T-cell immunity in vivo. Despite this important function, the molecular mechanisms by which they control T-cell activation are incompletely defined. Here we show that transitional B-cells produced more IL-10 and expressed higher levels of IL-10 receptor after CD40 engagement compared to other B-cell subsets. Furthermore, under this stimulatory condition, CD86 expressed by transitional B-cells was down regulated and T-cell proliferation was reduced. We provide evidence to demonstrate that the down-regulation of CD86 expression by transitional B-cells was due to the autocrine effect of IL-10, which in turn leads to decreased T-cell proliferation and TNF-α production. This analysis was further extended to peripheral B-cells in kidney transplant recipients. We observed that B-cells from patients tolerant to the graft maintained higher IL-10 production after CD40 ligation, which correlates with lower CD86 expression compared to patients with chronic rejection. Hence, the results obtained in this study shed light on a new alternative mechanism by which transitional B-cells inhibit T-cell proliferation and cytokine production.

  18. IL-10-produced by human transitional B-cells down-regulates CD86 expression on B-cells leading to inhibition of CD4+T-cell responses

    Science.gov (United States)

    Nova-Lamperti, Estefania; Fanelli, Giorgia; Becker, Pablo D.; Chana, Prabhjoat; Elgueta, Raul; Dodd, Philippa C.; Lord, Graham M.; Lombardi, Giovanna; Hernandez-Fuentes, Maria P.

    2016-01-01

    A novel subset of human regulatory B-cells has recently been described. They arise from within the transitional B-cell subpopulation and are characterised by the production of IL-10. They appear to be of significant importance in regulating T-cell immunity in vivo. Despite this important function, the molecular mechanisms by which they control T-cell activation are incompletely defined. Here we show that transitional B-cells produced more IL-10 and expressed higher levels of IL-10 receptor after CD40 engagement compared to other B-cell subsets. Furthermore, under this stimulatory condition, CD86 expressed by transitional B-cells was down regulated and T-cell proliferation was reduced. We provide evidence to demonstrate that the down-regulation of CD86 expression by transitional B-cells was due to the autocrine effect of IL-10, which in turn leads to decreased T-cell proliferation and TNF-α production. This analysis was further extended to peripheral B-cells in kidney transplant recipients. We observed that B-cells from patients tolerant to the graft maintained higher IL-10 production after CD40 ligation, which correlates with lower CD86 expression compared to patients with chronic rejection. Hence, the results obtained in this study shed light on a new alternative mechanism by which transitional B-cells inhibit T-cell proliferation and cytokine production. PMID:26795594

  19. Paradoxical aging in HIV: immune senescence of B Cells is most prominent in young age

    Science.gov (United States)

    George, Varghese K.; de Armas, Lesley R.; Pahwa, Rajendra; Sanchez, Celeste M.; Pallin, Maria Fernanda; Pan, Li; Cotugno, Nicola; Dickinson, Gordon; Rodriguez, Allan; Fischl, Margaret; Alcaide, Maria; Gonzalez, Louis; Palma, Paolo; Pahwa, Savita

    2017-01-01

    Combination antiretroviral therapies (cART) can lead to normal life expectancy in HIV-infected persons, and people aged >50 yrs represent the fastest growing HIV group. Although HIV and aging are independently associated with impaired humoral immunity, immune status in people aging with HIV is relatively unexplored. In this study influenza vaccination was used to probe age associated perturbations in the B cell compartment of HIV-negative “healthy controls” (HC) and virologically controlled HIV-infected participants on cART (HIV) (n=124), grouped by age as young (<40 yrs), middle-aged (40-59yrs) or old (≥60 yrs). H1N1 antibody response at d21 post-vaccination correlated inversely with age in both HC and HIV. Immunophenotyping of cryopreserved PBMC demonstrated increased frequencies of double negative B cells and decreased plasmablasts in old compared to young HC. Remarkably, young HIV were different from young HC but similar to old HC in B cell phenotype, influenza specific spontaneous (d7) or memory (d21) antibody secreting cells. We conclude that B cell immune senescence is a prominent phenomenon in young HIV in comparison to young HC, but distinctions between old HIV and old HC are less evident though both groups manifest age-associated B cell dysfunction. PMID:28448963

  20. Paradoxical aging in HIV: immune senescence of B Cells is most prominent in young age.

    Science.gov (United States)

    Rinaldi, Stefano; Pallikkuth, Suresh; George, Varghese K; de Armas, Lesley R; Pahwa, Rajendra; Sanchez, Celeste M; Pallin, Maria Fernanda; Pan, Li; Cotugno, Nicola; Dickinson, Gordon; Rodriguez, Allan; Fischl, Margaret; Alcaide, Maria; Gonzalez, Louis; Palma, Paolo; Pahwa, Savita

    2017-04-01

    Combination antiretroviral therapies (cART)can lead to normal life expectancy in HIV-infected persons, and people aged >50 yrs represent the fastest growing HIV group. Although HIV and aging are independently associated with impaired humoral immunity, immune status in people aging with HIV is relatively unexplored. In this study influenza vaccination was used to probe age associated perturbations in the B cell compartment of HIV-negative "healthy controls" (HC) and virologically controlled HIV-infected participants on cART (HIV) (n=124), grouped by age as young (aged (40-59yrs) or old ( > 60 yrs). H1N1 antibody response at d21 post-vaccination correlated inversely with age in both HC and HIV. Immunophenotyping of cryopreserved PBMC demonstrated increased frequencies of double negative B cells and decreased plasmablasts in old compared to young HC. Remarkably, young HIV were different from young HC but similar to old HC in B cell phenotype, influenza specific spontaneous (d7) or memory (d21) antibody secreting cells. We conclude that B cell immune senescence is a prominent phenomenon in young HIV in comparison to young HC, but distinctions between old HIV and old HC are less evident though both groups manifest age-associated B cell dysfunction.

  1. CXCL13 is the major determinant for B cell recruitment to the CSF during neuroinflammation

    Directory of Open Access Journals (Sweden)

    Kowarik Markus C

    2012-05-01

    Full Text Available Abstract Background The chemokines and cytokines CXCL13, CXCL12, CCL19, CCL21, BAFF and APRIL are believed to play a role in the recruitment of B cells to the central nervous system (CNS compartment during neuroinflammation. To determine which chemokines/cytokines show the strongest association with a humoral immune response in the cerebrospinal fluid (CSF, we measured their concentrations in the CSF and correlated them with immune cell subsets and antibody levels. Methods Cytokine/chemokine concentrations were measured in CSF and serum by ELISA in patients with non-inflammatory neurological diseases (NIND, n = 20, clinically isolated syndrome (CIS, n = 30, multiple sclerosis (MS, n = 20, Lyme neuroborreliosis (LNB, n = 8 and patients with other inflammatory neurological diseases (OIND, n = 30. Albumin, IgG, IgA and IgM were measured by nephelometry. CSF immune cell subsets were determined by seven-color flow cytometry. Results CXCL13 was significantly elevated in the CSF of all patient groups with inflammatory diseases. BAFF levels were significantly increased in patients with LNB and OIND. CXCL12 was significantly elevated in patients with LNB. B cells and plasmablasts were significantly elevated in the CSF of all patients with inflammatory diseases. CXCL13 showed the most consistent correlation with CSF B cells, plasmablasts and intrathecal Ig synthesis. Conclusions CXCL13 seems to be the major determinant for B cell recruitment to the CNS compartment in different neuroinflammatory diseases. Thus, elevated CSF CXCL13 levels rather reflect a strong humoral immune response in the CNS compartment than being specific for a particular disease entity.

  2. Interaction of Staphylococci with Human B cells.

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    Tyler K Nygaard

    Full Text Available Staphylococcus aureus is a leading cause of human infections worldwide. The pathogen produces numerous molecules that can interfere with recognition and binding by host innate immune cells, an initial step required for the ingestion and subsequent destruction of microbes by phagocytes. To better understand the interaction of this pathogen with human immune cells, we compared the association of S. aureus and S. epidermidis with leukocytes in human blood. We found that a significantly greater proportion of B cells associated with S. epidermidis relative to S. aureus. Complement components and complement receptors were important for the binding of B cells with S. epidermidis. Experiments using staphylococci inactivated by ultraviolet radiation and S. aureus isogenic deletion mutants indicated that S. aureus secretes molecules regulated by the SaeR/S two-component system that interfere with the ability of human B cells to bind this bacterium. We hypothesize that the relative inability of B cells to bind S. aureus contributes to the microbe's success as a human pathogen.

  3. Double-hit B-cell lymphomas

    NARCIS (Netherlands)

    Aukema, Sietse M.; Siebert, Reiner; Schuuring, Ed; van Imhoff, Gustaaf W.; Kluin-Nelemans, Hanneke C.; Boerma, Evert-Jan; Kluin, Philip M.

    2011-01-01

    In many B-cell lymphomas, chromosomal translocations are biologic and diagnostic hallmarks of disease. An intriguing subset is formed by the so-called double-hit (DH) lymphomas that are defined by a chromosomal breakpoint affecting the MYC/8q24 locus in combination with another recurrent breakpoint,

  4. Anti-CD20 B-cell depletion enhances monocyte reactivity in neuroimmunological disorders

    Directory of Open Access Journals (Sweden)

    Hohlfeld Reinhard

    2011-10-01

    Full Text Available Abstract Background Clinical trials evaluating anti-CD20-mediated B-cell depletion in multiple sclerosis (MS and neuromyelitis optica (NMO generated encouraging results. Our recent studies in the MS model experimental autoimmune encephalomyelitis (EAE attributed clinical benefit to extinction of activated B-cells, but cautioned that depletion of naïve B-cells may be undesirable. We elucidated the regulatory role of un-activated B-cells in EAE and investigated whether anti-CD20 may collaterally diminish regulatory B-cell properties in treatment of neuroimmunological disorders. Methods Myelin oligodendrocyte glycoprotein (MOG peptide-immunized C57Bl/6 mice were depleted of B-cells. Functional consequences for regulatory T-cells (Treg and cytokine production of CD11b+ antigen presenting cells (APC were assessed. Peripheral blood mononuclear cells from 22 patients receiving anti-CD20 and 23 untreated neuroimmunological patients were evaluated for frequencies of B-cells, T-cells and monocytes; monocytic reactivity was determined by TNF-production and expression of signalling lymphocytic activation molecule (SLAM. Results We observed that EAE-exacerbation upon depletion of un-activated B-cells closely correlated with an enhanced production of pro-inflammatory TNF by CD11b+ APC. Paralleling this pre-clinical finding, anti-CD20 treatment of human neuroimmunological disorders increased the relative frequency of monocytes and accentuated pro-inflammatory monocyte function; when reactivated ex vivo, a higher frequency of monocytes from B-cell depleted patients produced TNF and expressed the activation marker SLAM. Conclusions These data suggest that in neuroimmunological disorders, pro-inflammatory APC activity is controlled by a subset of B-cells which is eliminated concomitantly upon anti-CD20 treatment. While this observation does not conflict with the general concept of B-cell depletion in human autoimmunity, it implies that its safety and

  5. Compartment syndrome without pain!

    LENUS (Irish Health Repository)

    O'Sullivan, M J

    2012-02-03

    We report the case of a young male patient who underwent intra-medullary nailing for a closed, displaced mid-shaft fracture of tibia and fibula. He was commenced on patient controlled analgesia post-operatively. A diagnosis of compartment syndrome in the patient\\'s leg was delayed because he did not exhibit a pain response. This ultimately resulted in a below-knee amputation of the patient\\'s leg. We caution against the use of patient controlled analgesia in any traumatised limb distal to the hip or the shoulder.

  6. Fluorescently labeled dengue viruses as probes to identify antigen-specific memory B cells by multiparametric flow cytometry.

    Science.gov (United States)

    Woda, Marcia; Mathew, Anuja

    2015-01-01

    Low frequencies of memory B cells in the peripheral blood make it challenging to measure the functional and phenotypic characteristics of this antigen experienced subset of B cells without in vitro culture. To date, reagents are lacking to measure ex vivo frequencies of dengue virus (DENV)-specific memory B cells. We wanted to explore the possibility of using fluorescently labeled DENV as probes to detect antigen-specific memory B cells in the peripheral blood of DENV immune individuals. Alexa Fluor dye-labeled DENV yielded viable virus that could be stored at -80°C for long periods of time. Using a careful gating strategy and methods to decrease non-specific binding, we were able to identify a small frequency of B cells from dengue immune individuals that bound labeled DENV. Sorted DENV(+) B cells from immune, but not naïve donors secreted antibodies that bound DENV after in vitro stimulation. Overall, Alexa Fluor dye-labeled DENVs are useful reagents to enable the detection and characterization of memory B cells in DENV immune individuals. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Rictor positively regulates B cell receptor signaling by modulating actin reorganization via ezrin.

    Directory of Open Access Journals (Sweden)

    Lu Huang

    2017-08-01

    Full Text Available As the central hub of the metabolism machinery, the mammalian target of rapamycin complex 2 (mTORC2 has been well studied in lymphocytes. As an obligatory component of mTORC2, the role of Rictor in T cells is well established. However, the role of Rictor in B cells still remains elusive. Rictor is involved in B cell development, especially the peripheral development. However, the role of Rictor on B cell receptor (BCR signaling as well as the underlying cellular and molecular mechanism is still unknown. This study used B cell-specfic Rictor knockout (KO mice to investigate how Rictor regulates BCR signaling. We found that the key positive and negative BCR signaling molecules, phosphorylated Brutons tyrosine kinase (pBtk and phosphorylated SH2-containing inositol phosphatase (pSHIP, are reduced and enhanced, respectively, in Rictor KO B cells. This suggests that Rictor positively regulates the early events of BCR signaling. We found that the cellular filamentous actin (F-actin is drastically increased in Rictor KO B cells after BCR stimulation through dysregulating the dephosphorylation of ezrin. The high actin-ezrin intensity area restricts the lateral movement of BCRs upon stimulation, consequently reducing BCR clustering and BCR signaling. The reduction in the initiation of BCR signaling caused by actin alteration is associated with a decreased humoral immune response in Rictor KO mice. The inhibition of actin polymerization with latrunculin in Rictor KO B cells rescues the defects of BCR signaling and B cell differentiation. Overall, our study provides a new pathway linking cell metablism to BCR activation, in which Rictor regulates BCR signaling via actin reorganization.

  8. Modeling of compartment fire

    International Nuclear Information System (INIS)

    Sathiah, P.; Siccama, A.; Visser, D.; Komen, E.

    2011-01-01

    Fire accident in a containment is a serious threat to nuclear reactors. Fire can cause substantial loss to life and property. The risk posed by fire can also exceed the risk from internal events within a nuclear reactor. Numerous research efforts have been performed to understand and analyze the phenomenon of fire in nuclear reactor and its consequences. Modeling of fire is an important subject in the field of fire safety engineering. Two approaches which are commonly used in fire modeling are zonal modeling and field modeling. The objective of this work is to compare zonal and field modeling approach against a pool fired experiment performed in a well-confined compartment. Numerical simulations were performed against experiments, which were conducted within PRISME program under the framework of OECD. In these experiments, effects of ventilation flow rate on heat release rate in a confined and mechanically ventilated compartment is investigated. Time dependent changes in gas temperature and oxygen mass fraction were measured. The trends obtained by numerical simulation performed using zonal model and field model compares well with experiments. Further validation is needed before this code can be used for fire safety analyses. (author)

  9. Rac-mediated Stimulation of Phospholipase Cγ2 Amplifies B Cell Receptor-induced Calcium Signaling*♦

    Science.gov (United States)

    Walliser, Claudia; Tron, Kyrylo; Clauss, Karen; Gutman, Orit; Kobitski, Andrei Yu.; Retlich, Michael; Schade, Anja; Röcker, Carlheinz; Henis, Yoav I.; Nienhaus, G. Ulrich; Gierschik, Peter

    2015-01-01

    The Rho GTPase Rac is crucially involved in controlling multiple B cell functions, including those regulated by the B cell receptor (BCR) through increased cytosolic Ca2+. The underlying molecular mechanisms and their relevance to the functions of intact B cells have thus far remained unknown. We have previously shown that the activity of phospholipase Cγ2 (PLCγ2), a key constituent of the BCR signalosome, is stimulated by activated Rac through direct protein-protein interaction. Here, we use a Rac-resistant mutant of PLCγ2 to functionally reconstitute cultured PLCγ2-deficient DT40 B cells and to examine the effects of the Rac-PLCγ2 interaction on BCR-mediated changes of intracellular Ca2+ and regulation of Ca2+-regulated and nuclear-factor-of-activated-T-cell-regulated gene transcription at the level of single, intact B cells. The results show that the functional Rac-PLCγ2 interaction causes marked increases in the following: (i) sensitivity of B cells to BCR ligation; (ii) BCR-mediated Ca2+ release from intracellular stores; (iii) Ca2+ entry from the extracellular compartment; and (iv) nuclear translocation of the Ca2+-regulated nuclear factor of activated T cells. Hence, Rac-mediated stimulation of PLCγ2 activity serves to amplify B cell receptor-induced Ca2+ signaling. PMID:25903139

  10. Rituximab does not reset defective early B cell tolerance checkpoints

    Science.gov (United States)

    Chamberlain, Nicolas; Massad, Christopher; Oe, Tyler; Cantaert, Tineke; Herold, Kevan C.; Meffre, Eric

    2015-01-01

    Type 1 diabetes (T1D) patients show abnormalities in early B cell tolerance checkpoints, resulting in the accumulation of large numbers of autoreactive B cells in their blood. Treatment with rituximab, an anti-CD20 mAb that depletes B cells, has been shown to preserve β cell function in T1D patients and improve other autoimmune diseases, including rheumatoid arthritis and multiple sclerosis. However, it remains largely unknown how anti–B cell therapy thwarts autoimmunity in these pathologies. Here, we analyzed the reactivity of Abs expressed by single, mature naive B cells from 4 patients with T1D before and 52 weeks after treatment to determine whether rituximab resets early B cell tolerance checkpoints. We found that anti–B cell therapy did not alter the frequencies of autoreactive and polyreactive B cells, which remained elevated in the blood of all patients after rituximab treatment. Moreover, the limited proliferative history of autoreactive B cells after treatment revealed that these clones were newly generated B cells and not self-reactive B cells that had escaped depletion and repopulated the periphery through homeostatic expansion. We conclude that anti–B cell therapy may provide a temporary dampening of autoimmune processes through B cell depletion. However, repletion with autoreactive B cells may explain the relapse that occurs in many autoimmune patients after anti–B cell therapy. PMID:26642366

  11. Kidney compartment model

    International Nuclear Information System (INIS)

    Gullberg, G.T.

    1976-09-01

    A multiparameter kidney compartment model which quantitates the amount of iodohippurate concentration as a function of time in the blood, tissue, kidneys and bladder is developed from a system of differential equations which represent first order kinetics. The kinetic data are obtained using a gamma camera and an HP5407 computer system which allows one to delineate areas of interest for the blood and tissue, kidneys, and bladder thus separating the data into four data sets. The estimated tubular transit times have a high ratio of the signal to the variance whereas the estimates of the amount of iodohippurate in the blood, tissue and kidneys have a low ratio of the signal to the variance. Application of this model to patient data requires better statistics than available with conventional 131 I-hippurate doses; thus a true test of the efficacy awaits availability of 123 I-hippurate

  12. Primary Hepatosplenic Large B-Cell Lymphoma

    Directory of Open Access Journals (Sweden)

    M.R. Morales-Polanco

    2008-03-01

    Full Text Available Diffuse large B-cell lymphoma is the most common form of lymphoma. It usually begins in the lymph nodes; up to 40% may have an extranodal presentation. According to a definition of primary extranodal lymphoma with presentation only in extranodal sites, there are reports of large B-cell lymphomas limited to liver or spleen as separate entities, and to date there have been only three documented cases of primary hepatosplenic presentation. This paper reports a fourth case. Due to a review of the literature and the clinical course of the case reported, we conclude that primary hepatosplenic large B-cell lymphoma has been found predominantly in females older than 60 years. The patients reported had <2 months of evolution prior to diagnosis, prominent B symptoms, splenomegaly in three and hepatomegaly in two, none with lymph node involvement. All had thrombocytopenia and abnormal liver function tests; three had anemia and elevated serum lactic dehydrogenase levels, two with hemophagocytosis in bone marrow. Because of the previously mentioned data, it can be stated that primary hepatosplenic lymphoma is an uncommon and aggressive form of disease that requires immediate recognition and treatment.

  13. Cellular cooperation in lymphocyte activation. III. B-cell helper effect in the enhancement of T-cell response.

    Science.gov (United States)

    Kasahara, T; Kin, K; Itoh, Y; Kawai, T; Kano, Y; Shioiri-Nakano, K

    1979-01-01

    T and B cells were purified from human tonsil and peripheral blood by the removal of phagocytic cells, followed by filtration through a nylon fiber column (NC) and E-rosette formation. Purified T and B cells contained less than 1% of other cell types. The responses of T cells to concanavalin A (Con A) and soluble protein A were greatly enhanced in the presence of autologous B cells. Participation of B cells in T-cell enhancement was confirmed by the following observations: (a) purified B copulation, which was separated further from adherent B cells, retained its enhancing activity. (b) Another adherent cell-free B-cell preparation, which was purified from the NC-passed fraction, and (c) no T lymphoid but some B lymphoid cell lines, elicited strong T-cell enhancement. It was also found that the enhancing capacity of B cells required no metabolic activity, but rather an intact cell form and direct cell-to-cell contact with responding cells. The stimulatory determinants on B cells were resistant to trypsin and neuraminidase treatment. In this paper a hypothesis will be presented that at least two signals are prerequisite for the effective activation of T cells.

  14. Autoantibodies in autoimmune thyroid disease promote immune complex formation with self antigens and increase B cell and CD4+ T cell proliferation in response to self antigens

    DEFF Research Database (Denmark)

    Nielsen, Claus Henrik; Hegedüs, Laszlo; Leslie, Robert Graham Quinton

    2004-01-01

    B cells are centrally involved as antigen-presenting cells in certain autoimmune diseases. To establish whether autoantibodies form immune complexes (IC) with self-antigens in autoimmune thyroid disease (AITD) and promote B cell uptake of self-antigen, sera from patients with Hashimoto......'s thyroiditis (HT), Graves' disease (GD) and healthy controls were incubated with human thyroglobulin (Tg) before adding normal peripheral blood mononuclear cells. The deposition of immunoglobulins and C3 fragments on B cells was then assessed. Inclusion of Tg in serum from HT patients promoted B cell capture...

  15. Autoantibodies in autoimmune thyroid disease promote immune complex formation with self antigens and increase B cell and CD4+ T cell proliferation in response to self antigens

    DEFF Research Database (Denmark)

    Nielsen, Claus Henrik; Hegedüs, Laszlo; Leslie, Robert Graham Quinton

    2004-01-01

    's thyroiditis (HT), Graves' disease (GD) and healthy controls were incubated with human thyroglobulin (Tg) before adding normal peripheral blood mononuclear cells. The deposition of immunoglobulins and C3 fragments on B cells was then assessed. Inclusion of Tg in serum from HT patients promoted B cell capture......B cells are centrally involved as antigen-presenting cells in certain autoimmune diseases. To establish whether autoantibodies form immune complexes (IC) with self-antigens in autoimmune thyroid disease (AITD) and promote B cell uptake of self-antigen, sera from patients with Hashimoto...

  16. The dynamics of T and B cells in lymph node during chronic HIV infection: TFH and HIV, unhappy dance partners?

    Directory of Open Access Journals (Sweden)

    Jung Joo Hong

    2016-11-01

    Full Text Available Although the dynamics of germinal center (GC formation, TFH cell recruitment to B cell follicles within lymphoid organs and changes of lymphoid tissue architecture in HIV/SIV infection have been documented, the underlying immunopathology remains unclear. Here, we summarize what is known regarding the kinetics of TFH cells and GC B cells during the course of infection as well as the potential immunopathological features associated with structural changes in the lymphoid compartment. This review also explores the implications cell dynamics in the formation and maintenance of viral reservoirs in hyperplastic follicles of secondary lymphoid organs before and after viral suppressive antiretroviral therapy.

  17. Precursor B-cell lymphoblastic leukemia of the arm mimicking neurogenic tumor: case report

    Directory of Open Access Journals (Sweden)

    Sui Xiu-fang

    2012-07-01

    Full Text Available Abstract Precursor B-cell lymphoblastic lymphoma (PBLL is an infrequent subtype of lymphoblastic lymphoma (LBL that commonly affected site for the diagnosis is the skin, followed by the head and neck. In this report, we presented a special case of PBLL located at the left arm and detected with magnetic resonance imaging (MRI and ultrasonography (US. This kind of PBLL is similar to a peripheral nerve tumor in clinical and radiographic manifestation.

  18. Human Memory B Cells Targeting Staphylococcus aureus Exotoxins Are Prevalent with Skin and Soft Tissue Infection

    Directory of Open Access Journals (Sweden)

    Adam J. Pelzek

    2018-03-01

    Full Text Available Staphylococcus aureus is a Gram-positive opportunistic pathogen that causes superficial and invasive infections in the hospital and community. High mortality from infection emphasizes the need for improved methods for prevention and treatment. Although S. aureus possesses an arsenal of virulence factors that contribute to evasion of host defenses, few studies have examined long-term humoral and B-cell responses. Adults with acute-phase skin and soft tissue infections were recruited; blood samples were obtained; and S. aureus isolates, including methicillin-resistant strains, were subjected to genomic sequence analysis. In comparisons of acute-phase sera with convalescent-phase sera, a minority (37.5% of patients displayed 2-fold or greater increases in antibody titers against three or more S. aureus antigens, whereas nearly half exhibited no changes, despite the presence of toxin genes in most infecting strains. Moreover, enhanced antibody responses waned over time, which could reflect a defect in B-cell memory or long-lived plasma cells. However, memory B cells reactive with a range of S. aureus antigens were prevalent at both acute-phase and convalescent-phase time points. While some memory B cells exhibited toxin-specific binding, those cross-reactive with structurally related leucocidin subunits were dominant across patients, suggesting the targeting of conserved epitopes. Memory B-cell reactivity correlated with serum antibody levels for selected S. aureus exotoxins, suggesting a relationship between the cellular and humoral compartments. Overall, although there was no global defect in the representation of anti-S. aureus memory B cells, there was evidence of restrictions in the range of epitopes recognized, which may suggest potential therapeutic approaches for augmenting host defenses.

  19. The occurrence and significance of V gene mutations in B cell-derived human malignancy.

    Science.gov (United States)

    Stevenson, F K; Sahota, S S; Ottensmeier, C H; Zhu, D; Forconi, F; Hamblin, T J

    2001-01-01

    The classification of B cell tumors has relevance for refining and improving clinical strategies. However, consensus has been difficult to establish, and although a scheme is now available, objective criteria are desirable. Genetic technology will underpin and extend current knowledge, and it is certain to reveal further subdivisions of current tumor categories. The Ig variable region genes of B cell tumors present a considerable asset for this area of investigation. The unique sequences carried in neoplastic B cells are easily isolated and sequenced. In addition to acting as clone-specific markers of each tumor, they indicate where the cell has come from and track its history following transformation. There is emerging clinical value in knowing whether the cell of origin has encountered antigen and has moved from the naive compartment to the germinal center, where somatic mutation is activated. This is amply illustrated by the subdivision of chronic lymphocytic leukemia into two subsets, unmutated or mutated, each with very different prognosis. Other tumors may be subdivided in a similar way. Microarray technology is developing rapidly to probe gene expression and to further divide tumor categories. All these genetic analyses will provide objective data to enhance both our understanding of B cell tumors and our ability to treat them.

  20. Dynamics of Dengue Virus (DENV)–Specific B Cells in the Response to DENV Serotype 1 Infections, Using Flow Cytometry With Labeled Virions

    Science.gov (United States)

    Woda, Marcia; Friberg, Heather; Currier, Jeffrey R.; Srikiatkhachorn, Anon; Macareo, Louis R.; Green, Sharone; Jarman, Richard G.; Rothman, Alan L.; Mathew, Anuja

    2016-01-01

    Background. The development of reagents to identify and characterize antigen-specific B cells has been challenging. Methods. We recently developed Alexa Fluor–labeled dengue viruses (AF DENVs) to characterize antigen-specific B cells in the peripheral blood of DENV-immune individuals. Results. In this study, we used AF DENV serotype 1 (AF DENV-1) together with AF DENV-2 on peripheral blood mononuclear cells (PBMCs) from children in Thailand with acute primary or secondary DENV-1 infections to analyze the phenotypes of antigen-specific B cells that reflected their exposure or clinical diagnosis. DENV serotype-specific and cross-reactive B cells were identified in PBMCs from all subjects. Frequencies of AF DENV+ class-switched memory B cells (IgD−CD27+ CD19+ cells) reached up to 8% during acute infection and early convalescence. AF DENV–labeled B cells expressed high levels of CD27 and CD38 during acute infection, characteristic of plasmablasts, and transitioned into memory B cells (CD38−CD27+) at the early convalescent time point. There was higher activation of memory B cells early during acute secondary infection, suggesting reactivation from a previous DENV infection. Conclusions. AF DENVs reveal changes in the phenotype of DENV serotype–specific and cross-reactive B cells during and after natural DENV infection and could be useful in analysis of the response to DENV vaccination. PMID:27443614

  1. NKT Cell Responses to B Cell Lymphoma.

    Science.gov (United States)

    Li, Junxin; Sun, Wenji; Subrahmanyam, Priyanka B; Page, Carly; Younger, Kenisha M; Tiper, Irina V; Frieman, Matthew; Kimball, Amy S; Webb, Tonya J

    2014-06-01

    Natural killer T (NKT) cells are a unique subset of CD1d-restricted T lymphocytes that express characteristics of both T cells and natural killer cells. NKT cells mediate tumor immune-surveillance; however, NKT cells are numerically reduced and functionally impaired in lymphoma patients. Many hematologic malignancies express CD1d molecules and co-stimulatory proteins needed to induce anti-tumor immunity by NKT cells, yet most tumors are poorly immunogenic. In this study, we sought to investigate NKT cell responses to B cell lymphoma. In the presence of exogenous antigen, both mouse and human NKT cell lines produce cytokines following stimulation by B cell lymphoma lines. NKT cell populations were examined ex vivo in mouse models of spontaneous B cell lymphoma, and it was found that during early stages, NKT cell responses were enhanced in lymphoma-bearing animals compared to disease-free animals. In contrast, in lymphoma-bearing animals with splenomegaly and lymphadenopathy, NKT cells were functionally impaired. In a mouse model of blastoid variant mantle cell lymphoma, treatment of tumor-bearing mice with a potent NKT cell agonist, α-galactosylceramide (α-GalCer), resulted in a significant decrease in disease pathology. Ex vivo studies demonstrated that NKT cells from α-GalCer treated mice produced IFN-γ following α-GalCer restimulation, unlike NKT cells from vehicle-control treated mice. These data demonstrate an important role for NKT cells in the immune response to an aggressive hematologic malignancy like mantle cell lymphoma.

  2. Human CD40 ligand-expressing type 3 innate lymphoid cells induce IL-10-producing immature transitional regulatory B cells.

    Science.gov (United States)

    Komlósi, Zsolt I; Kovács, Nóra; van de Veen, Willem; Kirsch, Anna Isabella; Fahrner, Heinz Benedikt; Wawrzyniak, Marcin; Rebane, Ana; Stanic, Barbara; Palomares, Oscar; Rückert, Beate; Menz, Günter; Akdis, Mübeccel; Losonczy, György; Akdis, Cezmi A

    2017-09-20

    Type 3 innate lymphoid cells (ILC3s) are involved in maintenance of mucosal homeostasis; however, their role in immunoregulation has been unknown. Immature transitional regulatory B (itBreg) cells are innate-like B cells with immunosuppressive properties, and the in vivo mechanisms by which they are induced have not been fully clarified. We aimed to investigate the ILC3-B-cell interaction that probably takes place in human tonsils. ILC3s were isolated from peripheral blood and palatine tonsils, expanded, and cocultured with naive B cells. Tonsillar ILC3s and regulatory B cells were visualized with immunofluorescence histology. ILC3 frequencies were measured in tonsil tissue of allergic and nonallergic patients and in peripheral blood of allergic asthmatic patients and healthy control subjects. A mutually beneficial relationship was revealed between ILC3s and B cells: ILC3s induced IL-15 production in B cells through B cell-activating factor receptor, whereas IL-15, a potent growth factor for ILC3s, induced CD40 ligand (CD40L) expression on circulating and tonsillar ILC3s. IL-15-activated CD40L + ILC3s helped B-cell survival, proliferation, and differentiation of IL-10-secreting, PD-L1-expressing functional itBreg cells in a CD40L- and B cell-activating factor receptor-dependent manner. ILC3s and regulatory B cells were in close connection with each other in palatine tonsils. ILC3 frequency was reduced in tonsil tissue of allergic patients and in peripheral blood of allergic asthmatic patients. Human CD40L + ILC3s provide innate B-cell help and are involved in an innate immunoregulatory mechanism through induction of itBreg cell differentiation, which takes place in palatine tonsils in vivo. This mechanism, which can contribute to maintenance of immune tolerance, becomes insufficient in allergic diseases. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  3. Regulation of B cell differentiation by intracellular membrane associated proteins and microRNAs: role in the antibody response

    Directory of Open Access Journals (Sweden)

    Zheng eLou

    2015-10-01

    Full Text Available B cells are central to adaptive immunity and their functions in antibody responses are exquisitely regulated. As suggested by recent findings, B cell differentiation is mediated by intracellular membrane structures (including endosomes, lysosomes and autophagosomes and protein factors specifically associated with these membranes, including Rab7, Atg5 and Atg7. These factors participate in vesicle formation/trafficking, signal transduction and induction of gene expression to promote antigen presentation, CSR/SHM, and generation/maintenance of plasma cells and memory B cells. Their expression is induced in B cells activated to differentiate and further fine-tuned by immune-modulating microRNAs, which coordinates CSR/SHM, plasma cell differentiation and memory B cell differentiation. These short non-coding RNAs would individually target multiple factors associated with the same intracellular membrane compartments and collaboratively target a single factor in addition to regulate AID and Blimp-1. These, together with regulation of microRNA biogenesis and activities by endosomes and autophagosomes, show that intracellular membranes and microRNAs, two broadly relevant cell constituents, play important roles in balancing gene expression to specify B cell differentiation processes for optimal antibody responses.

  4. An Exponential Regression Model Reveals the Continuous Development of B Cell Subpopulations Used as Reference Values in Children

    Directory of Open Access Journals (Sweden)

    Christoph Königs

    2018-05-01

    Full Text Available B lymphocytes are key players in humoral immunity, expressing diverse surface immunoglobulin receptors directed against specific antigenic epitopes. The development and profile of distinct subpopulations have gained awareness in the setting of primary immunodeficiency disorders, primary or secondary autoimmunity and as therapeutic targets of specific antibodies in various diseases. The major B cell subpopulations in peripheral blood include naïve (CD19+ or CD20+IgD+CD27−, non-switched memory (CD19+ or CD20+IgD+CD27+ and switched memory B cells (CD19+ or CD20+IgD−CD27+. Furthermore, less common B cell subpopulations have also been described as having a role in the suppressive capacity of B cells to maintain self-tolerance. Data on reference values for B cell subpopulations are limited and only available for older age groups, neglecting the continuous process of human B cell development in children and adolescents. This study was designed to establish an exponential regression model to produce continuous reference values for main B cell subpopulations to reflect the dynamic maturation of the human immune system in healthy children.

  5. BMP-6 inhibits growth of mature human B cells; induction of Smad phosphorylation and upregulation of Id1

    Directory of Open Access Journals (Sweden)

    Kersten Christian

    2005-05-01

    Full Text Available Abstract Background Bone morphogenetic proteins (BMPs belong to the TGF-β superfamily and are secreted proteins with pleiotropic roles in many different cell types. A potential role of BMP-6 in the immune system has been implied by various studies of malignant and rheumatoid diseases. In the present study, we explored the role of BMP-6 in normal human peripheral blood B cells. Results The B cells were found to express BMP type I and type II receptors and BMP-6 rapidly induced phosphorylation of Smad1/5/8. Furthermore, Smad-phosphorylation was followed by upregulation of Id1 mRNA and Id1 protein, whereas Id2 and Id3 expression was not affected. Furthermore, we found that BMP-6 had an antiproliferative effect both in naïve (CD19+CD27- and memory B cells (CD19+CD27+ stimulated with anti-IgM alone or the combined action of anti-IgM and CD40L. Additionally, BMP-6 induced cell death in activated memory B cells. Importantly, the antiproliferative effect of BMP-6 in B-cells was completely neutralized by the natural antagonist, noggin. Furthermore, B cells were demonstrated to upregulate BMP-6 mRNA upon stimulation with anti-IgM. Conclusion In mature human B cells, BMP-6 inhibited cell growth, and rapidly induced phosphorylation of Smad1/5/8 followed by an upregulation of Id1.

  6. B cell lymphoma and myeloma in murine Gaucher's disease

    NARCIS (Netherlands)

    Pavlova, E. V.; Wang, S. Z.; Archer, J.; Dekker, N. [=Nick; Aerts, J. M. F. G.; Karlsson, S.; Cox, T. M.

    2013-01-01

    Multiple myeloma and B cell lymphoma are leading causes of death in Gaucher's disease but the nature of the stimulus driving the often noted clonal expansion of immunoglobulin-secreting B cells and cognate lymphoid malignancy is unknown. We investigated the long-term development of B cell

  7. Unique B cell differentiation profile in tolerant kidney transplant patients.

    Science.gov (United States)

    Chesneau, M; Pallier, A; Braza, F; Lacombe, G; Le Gallou, S; Baron, D; Giral, M; Danger, R; Guerif, P; Aubert-Wastiaux, H; Néel, A; Michel, L; Laplaud, D-A; Degauque, N; Soulillou, J-P; Tarte, K; Brouard, S

    2014-01-01

    Operationally tolerant patients (TOL) display a higher number of blood B cells and transcriptional B cell signature. As they rarely develop an allo-immune response, they could display an abnormal B cell differentiation. We used an in vitro culture system to explore T-dependent differentiation of B cells into plasma cells. B cell phenotype, apoptosis, proliferation, cytokine, immunoglobulin production and markers of differentiation were followed in blood of these patients. Tolerant recipients show a higher frequency of CD20(+) CD24(hi) CD38(hi) transitional and CD20(+) CD38(lo) CD24(lo) naïve B cells compared to patients with stable graft function, correlating with a decreased frequency of CD20(-) CD38(+) CD138(+) differentiated plasma cells, suggestive of abnormal B cell differentiation. B cells from TOL proliferate normally but produce more IL-10. In addition, B cells from tolerant recipients exhibit a defective expression of factors of the end step of differentiation into plasma cells and show a higher propensity for cell death apoptosis compared to patients with stable graft function. This in vitro profile is consistent with down-regulation of B cell differentiation genes and anti-apoptotic B cell genes in these patients in vivo. These data suggest that a balance between B cells producing IL-10 and a deficiency in plasma cells may encourage an environment favorable to the tolerance maintenance. © Copyright 2013 The American Society of Transplantation and the American Society of Transplant Surgeons.

  8. Intravascular Large B-Cell Lymphoma

    Directory of Open Access Journals (Sweden)

    Maria S. Khan MD, FACP

    2014-03-01

    Full Text Available Case Presentation . A 69-year-old Hispanic male, with a past history of diabetes and coronary disease, was admitted for fever, diarrhea, and confusion of 4 weeks duration. Physical examination showed a disoriented patient with multiple ecchymoses, possible ascites, and bilateral scrotal swelling. Hemoglobin was 6.7, prothrombin time (PT 21.4 seconds with international normalized ratio 2.1, partial thromboplastin time (PTT 55.6 seconds, fibrin split 10 µg/L, and lactate dehydrogenase (LDH 1231 IU/L. Except for a positive DNA test for Epstein–Barr virus (EBV infection, extensive diagnostic workup for infections, malignancy, or a neurological cause was negative. Mixing studies revealed a nonspecific inhibitor of PT and PTT but Factor VIII levels were normal. The patient was empirically treated with antibiotics but developed hypotension and died on day 27 of admission. At autopsy, patient was found to have intravascular diffuse large B-cell lymphoma involving skin, testes, lung, and muscles. The malignant cells were positive for CD20, CD791, Mum-1, and Pax-5 and negative for CD3, CD5, CD10, CD30, and Bcl-6. The malignant cells were 100% positive for Ki-67. Discussion . Intravascular large cell B-cell lymphoma (IVLBCL is rare form of diffuse large B-cell lymphoma and tends to proliferate within small blood vessels, particularly capillaries and postcapillary venules. The cause of its affinity for vascular bed remains unknown. In many reports, IVLBCL was associated with HIV, HHV8, and EBV infections. The fact that our case showed evidence of EBV infection lends support to the association of this diagnosis to viral illness. The available literature on this subject is scant, and in many cases, the diagnosis was made only at autopsy. The typical presentation of this disorder is with B symptoms, progressive neurologic deficits, and skin findings. Bone marrow, spleen, and liver are involved in a minority of patients. Nearly all patients have elevated LDH

  9. B cell lymphomas express CX3CR1 a non-B cell lineage adhesion molecule

    DEFF Research Database (Denmark)

    Andreasson, U.; Ek, S.; Merz, H.

    2008-01-01

    normally is not expressed on B cells, is expressed both at the mRNA and protein level in several subtypes of lymphoma. CX3CR1 has also shown to be involved in the homing to specific tissues that express the ligand, CX3CL1, in breast and prostate cancer and may thus be involved in dissemination of lymphoma......To study the differential expression of cell membrane-bound receptors and their potential role in growth and/or survival of the tumor cells, highly purified follicular lymphoma cells were analyzed, using gene expression analysis, and compared to non-malignant B cell populations. Filtering...... the genome for overexpressed genes coding for cell membrane-bound proteins/receptors resulted in a hit list of 27 identified genes. Among these, we have focused on the aberrant over expression of CX3CR1, in different types of B cell lymphoma, as compared to non-malignant B cells. We show that CX3CR1, which...

  10. Early appearance of germinal center–derived memory B cells and plasma cells in blood after primary immunization

    Science.gov (United States)

    Blink, Elizabeth J.; Light, Amanda; Kallies, Axel; Nutt, Stephen L.; Hodgkin, Philip D.; Tarlinton, David M.

    2005-01-01

    Immunization with a T cell–dependent antigen elicits production of specific memory B cells and antibody-secreting cells (ASCs). The kinetic and developmental relationships between these populations and the phenotypic forms they and their precursors may take remain unclear. Therefore, we examined the early stages of a primary immune response, focusing on the appearance of antigen-specific B cells in blood. Within 1 wk, antigen-specific B cells appear in the blood with either a memory phenotype or as immunoglobulin (Ig)G1 ASCs expressing blimp-1. The memory cells have mutated VH genes; respond to the chemokine CXCL13 but not CXCL12, suggesting recirculation to secondary lymphoid organs; uniformly express B220; show limited differentiation potential unless stimulated by antigen; and develop independently of blimp-1 expression. The antigen-specific IgG1 ASCs in blood show affinity maturation paralleling that of bone marrow ASCs, raising the possibility that this compartment is established directly by blood-borne ASCs. We find no evidence for a blimp-1–expressing preplasma memory compartment, suggesting germinal center output is restricted to ASCs and B220+ memory B cells, and this is sufficient to account for the process of affinity maturation. PMID:15710653

  11. B Cell Receptor-Mediated Internalization of Salmonella: A Novel Pathway for Autonomous B Cell Activation and Antibody Production

    NARCIS (Netherlands)

    Souwer, Yuri; Griekspoor, Alexander; Jorritsma, Tineke; de Wit, Jelle; Janssen, Hans; Neefjes, Jacques; van Ham, S. Marieke

    2009-01-01

    The present paradigm is that primary B cells are nonphagocytosing cells. In this study, we demonstrate that human primary B cells are able to internalize bacteria when the bacteria are recognized by the BCR. BCR-mediated internalization of Salmonella typhimurium results in B cell differentiation and

  12. Adhesion molecule profiles of B-cell non-Hodgkin's lymphomas in the leukemic phase

    Directory of Open Access Journals (Sweden)

    D.M. Matos

    2006-10-01

    Full Text Available We evaluated the expression of 10 adhesion molecules on peripheral blood tumor cells of 17 patients with chronic lymphocytic leukemia, 17 with mantle-cell lymphoma, and 13 with nodal or splenic marginal B-cell lymphoma, all in the leukemic phase and before the beginning of any therapy. The diagnosis of B-cell non-Hodgkin's lymphomas was based on cytological, histological, immunophenotypic, and molecular biology methods. The mean fluorescence intensity of the adhesion molecules in tumor cells was measured by flow cytometry of CD19-positive cells and differed amongst the types of lymphomas. Comparison of chronic lymphocytic leukemia and mantle-cell lymphoma showed that the former presented a higher expression of CD11c and CD49c, and a lower expression of CD11b and CD49d adhesion molecules. Comparison of chronic lymphocytic leukemia and marginal B-cell lymphoma showed that the former presented a higher expression of CD49c and a lower expression of CD11a, CD11b, CD18, CD49d, CD29, and CD54. Finally, comparison of mantle-cell lymphoma and marginal B-cell lymphoma showed that marginal B-cell lymphoma had a higher expression of CD11a, CD11c, CD18, CD29, and CD54. Thus, the CD49c/CD49d pair consistently demonstrated a distinct pattern of expression in chronic lymphocytic leukemia compared with mantle-cell lymphoma and marginal B-cell lymphoma, which could be helpful for the differential diagnosis. Moreover, the distinct profiles of adhesion molecules in these diseases may be responsible for their different capacities to invade the blood stream.

  13. Drug Modulators of B Cell Signaling Pathways and Epstein-Barr Virus Lytic Activation.

    Science.gov (United States)

    Kosowicz, John G; Lee, Jaeyeun; Peiffer, Brandon; Guo, Zufeng; Chen, Jianmeng; Liao, Gangling; Hayward, S Diane; Liu, Jun O; Ambinder, Richard F

    2017-08-15

    Epstein-Barr virus (EBV) is a ubiquitous human gammaherpesvirus that establishes a latency reservoir in B cells. In this work, we show that ibrutinib, idelalisib, and dasatinib, drugs that block B cell receptor (BCR) signaling and are used in the treatment of hematologic malignancies, block BCR-mediated lytic induction at clinically relevant doses. We confirm that the immunosuppressive drugs cyclosporine and tacrolimus also inhibit BCR-mediated lytic induction but find that rapamycin does not inhibit BCR-mediated lytic induction. Further investigation shows that mammalian target of rapamycin complex 2 (mTORC2) contributes to BCR-mediated lytic induction and that FK506-binding protein 12 (FKBP12) binding alone is not adequate to block activation. Finally, we show that BCR signaling can activate EBV lytic induction in freshly isolated B cells from peripheral blood mononuclear cells (PBMCs) and that activation can be inhibited by ibrutinib or idelalisib. IMPORTANCE EBV establishes viral latency in B cells. Activation of the B cell receptor pathway activates lytic viral expression in cell lines. Here we show that drugs that inhibit important kinases in the BCR signaling pathway inhibit activation of lytic viral expression but do not inhibit several other lytic activation pathways. Immunosuppressant drugs such as cyclosporine and tacrolimus but not rapamycin also inhibit BCR-mediated EBV activation. Finally, we show that BCR activation of lytic infection occurs not only in tumor cell lines but also in freshly isolated B cells from patients and that this activation can be blocked by BCR inhibitors. Copyright © 2017 American Society for Microbiology.

  14. B cell signature during inactive systemic lupus is heterogeneous: toward a biological dissection of lupus.

    Directory of Open Access Journals (Sweden)

    Jean-Claude Garaud

    Full Text Available Systemic lupus erythematosous (SLE is an autoimmune disease with an important clinical and biological heterogeneity. B lymphocytes appear central to the development of SLE which is characterized by the production of a large variety of autoantibodies and hypergammaglobulinemia. In mice, immature B cells from spontaneous lupus prone animals are able to produce autoantibodies when transferred into immunodeficient mice, strongly suggesting the existence of intrinsic B cell defects during lupus. In order to approach these defects in humans, we compared the peripheral B cell transcriptomas of quiescent lupus patients to normal B cell transcriptomas. When the statistical analysis is performed on the entire group of patients, the differences between patients and controls appear quite weak with only 14 mRNA genes having a false discovery rate ranging between 11 and 17%, with 6 underexpressed genes (PMEPA1, TLR10, TRAF3IP2, LDOC1L, CD1C and EGR1. However, unforced hierarchical clustering of the microarrays reveals a subgroup of lupus patients distinct from both the controls and the other lupus patients. This subgroup has no detectable clinical or immunological phenotypic peculiarity compared to the other patients, but is characterized by 1/an IL-4 signature and 2/the abnormal expression of a large set of genes with an extremely low false discovery rate, mainly pointing to the biological function of the endoplasmic reticulum, and more precisely to genes implicated in the Unfolded Protein Response, suggesting that B cells entered an incomplete BLIMP1 dependent plasmacytic differentiation which was undetectable by immunophenotyping. Thus, this microarray analysis of B cells during quiescent lupus suggests that, despite a similar lupus phenotype, different biological roads can lead to human lupus.

  15. Regulation of normal B-cell differentiation and malignant B-cell survival by OCT2.

    Science.gov (United States)

    Hodson, Daniel J; Shaffer, Arthur L; Xiao, Wenming; Wright, George W; Schmitz, Roland; Phelan, James D; Yang, Yandan; Webster, Daniel E; Rui, Lixin; Kohlhammer, Holger; Nakagawa, Masao; Waldmann, Thomas A; Staudt, Louis M

    2016-04-05

    The requirement for the B-cell transcription factor OCT2 (octamer-binding protein 2, encoded by Pou2f2) in germinal center B cells has proved controversial. Here, we report that germinal center B cells are formed normally after depletion of OCT2 in a conditional knockout mouse, but their proliferation is reduced and in vivo differentiation to antibody-secreting plasma cells is blocked. This finding led us to examine the role of OCT2 in germinal center-derived lymphomas. shRNA knockdown showed that almost all diffuse large B-cell lymphoma (DLBCL) cell lines are addicted to the expression of OCT2 and its coactivator OCA-B. Genome-wide chromatin immunoprecipitation (ChIP) analysis and gene-expression profiling revealed the broad transcriptional program regulated by OCT2 that includes the expression of STAT3, IL-10, ELL2, XBP1, MYC, TERT, and ADA. Importantly, genetic alteration of OCT2 is not a requirement for cellular addiction in DLBCL. However, we detected amplifications of the POU2F2 locus in DLBCL tumor biopsies and a recurrent mutation of threonine 223 in the DNA-binding domain of OCT2. This neomorphic mutation subtly alters the DNA-binding preference of OCT2, leading to the transactivation of noncanonical target genes including HIF1a and FCRL3 Finally, by introducing mutations designed to disrupt the OCT2-OCA-B interface, we reveal a requirement for this protein-protein interface that ultimately might be exploited therapeutically. Our findings, combined with the predominantly B-cell-restricted expression of OCT2 and the absence of a systemic phenotype in our knockout mice, suggest that an OCT2-targeted therapeutic strategy would be efficacious in both major subtypes of DLBCL while avoiding systemic toxicity.

  16. Double-compartment wrist arthrography

    International Nuclear Information System (INIS)

    Quinn, S.F.; Pittman, C.; Belsole, R.; Greene, T.L.; Rayhack, J.; Clark, R.A.; King, P.S.

    1987-01-01

    Seventy patients with clinical wrist problems were studied with double-compartment wrist arthrography. Midcarpal and radiocarpal compartment arthrograms were obtained in all patients. Digital subtraction technique was used to subtract out contrast from the first compartmental injection. Digital technique also allowed a dynamic record of each injection, which helped determine sites of intercompartmental communication. Postarthrography exercises recorded on videotape were performed after each injection. There were 34 normal studies. Abnormalities in the other 36 patients included: scapholunate communication (n = 9), lunatotriquetral communication (n = 6), communication with tendon sheaths (n = 4), communication with distal radioulnar compartment (n = 14), abnormal synovium process (n = 9), and communication through the radial or ulnar collateral ligament (n = 3). Double-compartment wrist arthrography may provide additional information for complex problems of the wrist

  17. The regulatory roles of B cell subsets in transplantation.

    Science.gov (United States)

    Chu, Zhulang; Zou, Weilong; Xu, Yanan; Sun, Qiquan; Zhao, Yong

    2018-02-01

    B cells mediate allograft rejection through antigen presentation, and production of cytokines and antibodies. More and more immunosuppressive agents specifically targeting B cells and plasma cells have been applied in clinical transplantation. However, recent studies have indicated the regulatory roles of B cells. Therefore, it is vital to clarify the different effects of B cell subsets in organ transplantation so that we can completely understand the diverse functions of B cells in transplantation. Areas covered: This review focuses on the regulatory roles of B cells in transplantation. B cell subsets with immune modulation and factors mediating immunosuppressive functions of regulatory B (Breg) cells were analyzed. Therapies targeting B cells and the application of B cells for transplant tolerance induction were discussed. Expert commentary: Besides involving rejection, B cells could also play regulatory roles in transplantation. Breg cells and the related markers may be used to predict the immune tolerant state in transplant recipients. New therapeutic strategies targeting B cells should be explored to promote tolerance induction with less impact on the host's protective immunity in organ transplanted patients.

  18. Overexpression of Fc receptor-like 1 associated with B-cell activation during hepatitis B virus infection

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ke [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi, Jiangsu Province (China); Pei, Hao [Wuxi Hospital of Infectious Disease, Wuxi, Jiangsu Province (China); Huang, Biao; Yang, Run-Lin [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi, Jiangsu Province (China); Wu, Hang-Yuan [Wuxi Hospital of Infectious Disease, Wuxi, Jiangsu Province (China); Zhu, Xue; Zhu, Lan [Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi, Jiangsu Province (China)

    2012-08-17

    The role of B cells in the pathogenesis of hepatitis B virus (HBV) infection has not been explored in depth. In the present study, the activation status of B cells from peripheral blood of healthy controls (N = 20) and patients with acute hepatitis B (AHB, N = 15) or chronic hepatitis B (CHB, N = 30) was evaluated by measuring the expression levels of B-cell activation markers CD69 and CD86, using quantitative real-time PCR and flow cytometry. Moreover, the potential mechanism underlying B-cell activation during HBV infection was further investigated by analyzing the expression profile of FCRL1, an intrinsic activation molecule of B cells. An elevation in the levels of B-cell activation markers including CD69 and CD86 was observed in the AHB patients (44.31 ± 9.27, 27.64 ± 9.26%) compared to CHB patients (30.35 ± 11.27, 18.41 ± 6.56%, P < 0.05), which was still higher than healthy controls (12.23 ± 7.84, 8.22 ± 3.43%, P < 0.05). Furthermore, the expression of FCRL1 was found to be similar to B-cell activation markers, which was highest in AHB patients (70.15 ± 17.11%), lowest in healthy donors (36.32 ± 9.98%, P < 0.05) and half-way between these levels in patients with CHB (55.17 ± 12.03%, P < 0.05). The results were positively associated with aberrant B-cell activation. These data suggest that B cells can play a role in HBV infection, and therefore more effort should be devoted to exploring their functions.

  19. Expression of Tumor Necrosis Factor Receptor 2 Characterizes TLR9-Driven Formation of Interleukin-10-Producing B Cells

    Directory of Open Access Journals (Sweden)

    Olga Ticha

    2018-01-01

    Full Text Available B cell-derived interleukin-10 (IL-10 production has been described as a hallmark for regulatory function in B lymphocytes. However, there is an ongoing debate on the origin of IL-10-secreting B cells and lack of specific surface markers has turned into an important obstacle for studying human B regulatory cells. In this study, we propose that tumor necrosis factor receptor 2 (TNFR2 expression can be used for enrichment of IL-10-secreting B cells. Our data confirm that IL-10 production can be induced by TLR9 stimulation with CpG ODN and that IL-10 secretion accompanies differentiation of peripheral blood B cells into plasma blasts. We further show that CpG ODN stimulation induces TNFR2 expression, which correlates with IL-10 secretion and terminal differentiation. Indeed, flow cytometric sorting of TNFR2+ B cells revealed that TNFR2+ and TNFR2− fractions correspond to IL-10+ and IL-10− fractions, respectively. Furthermore, CpG-induced TNFR2+ B cells were predominantly found in the IgM+ CD27+ B cell subset and spontaneously released immunoglobulin. Finally, our data corroborate the functional impact of TNFR2 by demonstrating that stimulation with a TNFR2 agonist significantly augments IL-10 and IL-6 production in B cells. Altogether, our data highlight a new role for TNFR2 in IL-10-secreting human B lymphocytes along with the potential to exploit this finding for sorting and isolation of this currently ill-defined B cell subset.

  20. Impact of tofacitinib treatment on human B-cells in vitro and in vivo.

    Science.gov (United States)

    Rizzi, Marta; Lorenzetti, Raquel; Fischer, Kathleen; Staniek, Julian; Janowska, Iga; Troilo, Arianna; Strohmeier, Valentina; Erlacher, Miriam; Kunze, Mirjam; Bannert, Bettina; Kyburz, Diego; Voll, Reinhard E; Venhoff, Nils; Thiel, Jens

    2017-02-01

    B-cells are pivotal to the pathogenesis of rheumatoid arthritis and tofacitinib, a JAK inhibitor, is effective and safe in its treatment. Tofacitinib interferes with signal transduction via cytokine receptors using the common γ-chain. Despite extensive data on T-lymphocytes, the impact of tofacitinib on B-lymphocytes is poorly understood. In this study we assessed the effect of tofacitinib on B-lymphocyte differentiation and function. Tofacitinib treatment strongly impaired in vitro plasmablast development, immunoglobulin secretion and induction of B-cell fate determining transcription factors, Blimp-1, Xbp-1, and IRF-4, in naïve B-cells. Interestingly, class switch and activation-induced cytidine deaminase (AICDA) induction was only slightly reduced in activated naïve B-cells. The effect of tofacitinib on plasmablast formation, immunoglobulin secretion and proliferation was less profound, when peripheral blood B-cells, including not only naïve but also memory B-cells, were stimulated. In line with these in vitro results, the relative distribution of B-cell populations remained stable in tofacitinib treated patients. Nevertheless, a temporary increase in absolute B-cell numbers was observed 6-8 weeks after start of treatment. In addition, B-cells isolated from tofacitinib treated patients responded rapidly to in vitro activation. We demonstrate that tofacitinib has a direct impact on human naïve B-lymphocytes, independently from its effect on T-lymphocytes, by impairing their development into plasmablasts and immunoglobulin secretion. The major effect of tofacitinib on naïve B-lymphocyte development points to the potential inability of tofacitinib-treated patients to respond to novel antigens, and suggests planning vaccination strategies prior to tofacitinib treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. BAFF promotes regulatory T-cell apoptosis and blocks cytokine production by activating B cells in primary biliary cirrhosis

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Bo; Hu, Mintao [Department of Hepatology, Wuxi Infectious Diseases Hospital, Wuxi, Jiangsu (China); Zhang, Peng [Nanjing Medical University, Nanjing, Jiangsu (China); Cao, Hong [Department of Hepatology, Wuxi Infectious Diseases Hospital, Wuxi, Jiangsu (China); Wang, Yongzhen [The Second Hospital of Nanjing, Nanjing, Jiangsu (China); Wang, Zheng; Su, Tingting [Department of Hepatology, Wuxi Infectious Diseases Hospital, Wuxi, Jiangsu (China)

    2013-05-10

    Primary biliary cirrhosis (PBC) is a chronic and slowly progressive cholestatic liver disease of autoimmune etiology. A number of questions regarding its etiology are unclear. CD4+CD25+ regulatory T cells (Tregs) play a critical role in self-tolerance and, for unknown reasons, their relative number is reduced in PBC patients. B-cell-activating factor (BAFF) is a key survival factor during B-cell maturation and its concentration is increased in peripheral blood of PBC patients. It has been reported that activated B cells inhibit Treg cell proliferation and there are no BAFF receptors on Tregs. Therefore, we speculated that excessive BAFF may result in Treg reduction via B cells. To prove our hypothesis, we isolated Tregs and B cells from PBC and healthy donors. BAFF and IgM concentrations were then analyzed by ELISA and CD40, CD80, CD86, IL-10, and TGF-β expression in B cells and Tregs were measured by flow cytometry. BAFF up-regulated CD40, CD80, CD86, and IgM expression in B cells. However, BAFF had no direct effect on Treg cell apoptosis and cytokine secretion. Nonetheless, we observed that BAFF-activated B cells could induce Treg cell apoptosis and reduce IL-10 and TGF-β expression. We also showed that BAFF-activated CD4+ T cells had no effect on Treg apoptosis. Furthermore, we verified that bezafibrate, a hypolipidemic drug, can inhibit BAFF-induced Treg cell apoptosis. In conclusion, BAFF promotes Treg cell apoptosis and inhibits cytokine production by activating B cells in PBC patients. The results of this study suggest that inhibition of BAFF activation is a strategy for PBC treatment.

  2. Systemic Inflammation in Progressive Multiple Sclerosis Involves Follicular T-Helper, Th17- and Activated B-Cells and Correlates with Progression

    DEFF Research Database (Denmark)

    Romme Christensen, Jeppe; Börnsen, Lars; Ratzer, Rikke

    2013-01-01

    with disease progression, using flow cytometry and gene expression analysis of CD4(+) and CD8(+)T-cells, B-cells, monocytes and dendritic cells. Furthermore, gene expression of cerebrospinal fluid cells was studied. Flow cytometry studies revealed increased frequencies of ICOS(+)TFH-cells in peripheral blood...... increased in PPMS and SPMS. In the analysis of B-cells, we found a significant increase of plasmablasts and DC-SIGN(+) and CD83(+)B-cells in SPMS. ICOS(+)TFH-cells and DC-SIGN(+)B-cells correlated with disease progression in SPMS patients. Gene expression analysis of peripheral blood cell subsets...... substantiated the flow cytometry findings by demonstrating increased expression of IL21, IL21R and ICOS in CD4(+)T-cells in progressive MS. Cerebrospinal fluid cells from RRMS and progressive MS (pooled SPMS and PPMS patients) had increased expression of TFH-cell and plasmablast markers. In conclusion...

  3. CD24(hi)CD27⁺ and plasmablast-like regulatory B cells in human chronic graft-versus-host disease.

    Science.gov (United States)

    de Masson, Adèle; Bouaziz, Jean-David; Le Buanec, Hélène; Robin, Marie; O'Meara, Alix; Parquet, Nathalie; Rybojad, Michel; Hau, Estelle; Monfort, Jean-Benoît; Branchtein, Mylène; Michonneau, David; Dessirier, Valérie; Sicre de Fontbrune, Flore; Bergeron, Anne; Itzykson, Raphaël; Dhédin, Nathalie; Bengoufa, Djaouida; Peffault de Latour, Régis; Xhaard, Aliénor; Bagot, Martine; Bensussan, Armand; Socié, Gérard

    2015-03-12

    Interleukin 10 (IL-10)-producing B cells (regulatory B cells [Bregs]) regulate autoimmunity in mice and humans, and a regulatory role of IL-10-producing plasma cells has been described in mice. Dysfunction of B cells that maintain homeostasis may play a role in the pathogenesis of chronic graft-versus-host disease (cGVHD) after allogeneic stem cell transplantation. Here, we found a relation between decreased Breg frequencies and cGVHD severity. An impaired ability of B cells to produce IL-10, possibly linked to poor signal transducer and activator of transcription 3 and extracellular signal-regulated kinase phosphorylation, was found in patients with active cGVHD. IL-10 production was not confined to a single B-cell subset, but enriched in both the CD24(hi)CD27(+) and CD27(hi)CD38(hi) plasmablast B-cell compartments. In vitro plasmablast differentiation increased the frequency of IL-10-producing B cells. We confirmed that allogeneic transplant recipients had an impaired reconstitution of the memory B-cell pool. cGVHD patients had less CD24(hi)CD27(+) B cells and IL-10-producing CD24(hi)CD27(+) B cells. Patients with cGVHD had increased plasmablast frequencies but decreased IL-10-producing plasmablasts. These results suggest a role of CD24(hi)CD27(+) B-cell and plasmablast-derived IL-10 in the regulation of human cGVHD. © 2015 by The American Society of Hematology.

  4. Dual-Compartment Inflatable Suitlock

    Science.gov (United States)

    Kennedy, Kriss J.; Guirgis, Peggy L.; Boyle, Robert M.

    2013-01-01

    There is a need for an improvement over current NASA Extravehicular Activity (EVA) technology. The technology must allow the capacity for quicker, more efficient egress/ingress, allow for shirtsleeve suit maintenance, be compact in transport, and be applicable to environments ranging from planetary surface (partial-g) to orbital or deep space zero-g environments. The technology must also be resistant to dust and other foreign contaminants that may be present on or around a planetary surface. The technology should be portable, and be capable of docking with a variety of habitats, ports, stations, vehicles, and other pressurized modules. The Dual-Compartment Inflatable Suitlock (DCIS) consists of three hard inline bulkheads, separating two cylindrical membrane-walled compartments. The Inner Bulkhead can be fitted with a variety of hatch types, docking flanges, and mating hardware, such as the Common Berthing Mechanism (CBM), for the purpose of mating with vehicles, habitats, and other pressurized modules. The Inner Bulkhead and Center Bulkhead function as the end walls of the Inner Compartment, which during operations, would stay pressurized, either matching the pressure of the habitat or acting as a lower-pressure transitional volume. The Inner Compartment contains donning/doffing fixtures and inner suit-port hatches. The Center Bulkhead has two integrated suit-ports along with a maintenance hatch. The Center Bulkhead and Outer Bulkhead function as the end walls of the Outer Compartment, which stays at vacuum during normal operations. This allows the crewmember to quickly don a suit, and egress the suitlock without waiting for the Outer Compartment to depressurize. The Outer Compartment can be pressurized infrequently for both nominal and off-nominal suit maintenance tasks, allowing shirtsleeve inspections and maintenance/repair of the environmental suits. The Outer Bulkhead has a pressure-assisted hatch door that stays open and stowed during EVA operations, but can

  5. In Vitro Measles Virus Infection of Human Lymphocyte Subsets Demonstrates High Susceptibility and Permissiveness of both Naive and Memory B Cells.

    Science.gov (United States)

    Laksono, Brigitta M; Grosserichter-Wagener, Christina; de Vries, Rory D; Langeveld, Simone A G; Brem, Maarten D; van Dongen, Jacques J M; Katsikis, Peter D; Koopmans, Marion P G; van Zelm, Menno C; de Swart, Rik L

    2018-04-15

    Measles is characterized by a transient immune suppression, leading to an increased risk of opportunistic infections. Measles virus (MV) infection of immune cells is mediated by the cellular receptor CD150, expressed by subsets of lymphocytes, dendritic cells, macrophages, and thymocytes. Previous studies showed that human and nonhuman primate memory T cells express higher levels of CD150 than naive cells and are more susceptible to MV infection. However, limited information is available about the CD150 expression and relative susceptibility to MV infection of B-cell subsets. In this study, we assessed the susceptibility and permissiveness of naive and memory T- and B-cell subsets from human peripheral blood or tonsils to in vitro MV infection. Our study demonstrates that naive and memory B cells express CD150, but at lower frequencies than memory T cells. Nevertheless, both naive and memory B cells proved to be highly permissive to MV infection. Furthermore, we assessed the susceptibility and permissiveness of various functionally distinct T and B cells, such as helper T (T H ) cell subsets and IgG- and IgA-positive memory B cells, in peripheral blood and tonsils. We demonstrated that T H 1T H 17 cells and plasma and germinal center B cells were the subsets most susceptible and permissive to MV infection. Our study suggests that both naive and memory B cells, along with several other antigen-experienced lymphocytes, are important target cells of MV infection. Depletion of these cells potentially contributes to the pathogenesis of measles immune suppression. IMPORTANCE Measles is associated with immune suppression and is often complicated by bacterial pneumonia, otitis media, or gastroenteritis. Measles virus infects antigen-presenting cells and T and B cells, and depletion of these cells may contribute to lymphopenia and immune suppression. Measles has been associated with follicular exhaustion in lymphoid tissues in humans and nonhuman primates, emphasizing the

  6. Adipose Tissue Inflammation Induces B Cell Inflammation and Decreases B Cell Function in Aging

    Directory of Open Access Journals (Sweden)

    Daniela Frasca

    2017-08-01

    Full Text Available Aging is the greatest risk factor for developing chronic diseases. Inflamm-aging, the age-related increase in low-grade chronic inflammation, may be a common link in age-related diseases. This review summarizes recent published data on potential cellular and molecular mechanisms of the age-related increase in inflammation, and how these contribute to decreased humoral immune responses in aged mice and humans. Briefly, we cover how aging and related inflammation decrease antibody responses in mice and humans, and how obesity contributes to the mechanisms for aging through increased inflammation. We also report data in the literature showing adipose tissue infiltration with immune cells and how these cells are recruited and contribute to local and systemic inflammation. We show that several types of immune cells infiltrate the adipose tissue and these include macrophages, neutrophils, NK cells, innate lymphoid cells, eosinophils, T cells, B1, and B2 cells. Our main focus is how the adipose tissue affects immune responses, in particular B cell responses and antibody production. The role of leptin in generating inflammation and decreased B cell responses is also discussed. We report data published by us and by other groups showing that the adipose tissue generates pro-inflammatory B cell subsets which induce pro-inflammatory T cells, promote insulin resistance, and secrete pathogenic autoimmune antibodies.

  7. The kinetics of early T and B cell immune recovery after bone marrow transplantation in RAG-2-deficient SCID patients.

    Directory of Open Access Journals (Sweden)

    Atar Lev

    Full Text Available The kinetics of T and B cell immune recovery after bone marrow transplantation (BMT is affected by many pre- and post-transplant factors. Because of the profoundly depleted baseline T and B cell immunity in recombination activating gene 2 (RAG-2-deficient severe combined immunodeficiency (SCID patients, some of these factors are eliminated, and the immune recovery after BMT can then be clearly assessed. This process was followed in ten SCID patients in parallel to their associated transplant-related complications. Early peripheral presence of T and B cells was observed in 8 and 4 patients, respectively. The latter correlated with pre-transplant conditioning therapy. Cells from these patients carried mainly signal joint DNA episomes, indicative of newly derived B and T cells. They were present before the normalization of the T cell receptor (TCR and the B cell receptor (BCR repertoire. Early presentation of the ordered TCR gene rearrangements after BMT occurred simultaneously, but this pattern was heterogeneous over time, suggesting different and individual thymic recovery processes. Our findings early after transplant could suggest the long-term patients' clinical outcome. Early peripheral presence of newly produced B and T lymphocytes from their production and maturation sites after BMT suggests donor stem cell origin rather than peripheral expansion, and is indicative of successful outcome. Peripheral detection of TCR excision circles and kappa-deleting recombination excision circles in RAG-2-deficient SCID post-BMT are early markers of T and B cell reconstitution, and can be used to monitor outcome and tailor specific therapy for patients undergoing BMT.

  8. Brucella abortus-infected B cells induce osteoclastogenesis.

    Science.gov (United States)

    Pesce Viglietti, Ayelén Ivana; Arriola Benitez, Paula Constanza; Giambartolomei, Guillermo Hernán; Delpino, María Victoria

    2016-09-01

    Brucella abortus is an intracellular bacterium that establishes lifelong infections in livestock and humans although the mechanisms of its chronicity are poorly understood. Activated B cells have long lifespan and B. abortus infection activates B cells. Our results indicate that the direct infection of B cells with B. abortus induced matrix metalloproteinase-9 (MMP-9), receptor activator for NF κB ligand (RANKL), tumor necrosis factor (TNF)-α and interleukin (IL)-6 secretion. In addition, supernatants from B. abortus-infected B cells induced bone marrow-derived monocytes to undergo osteoclastogenesis. Using osteoprotegerin, RANKL's decoy receptor, we determined that RANKL is involved in osteoclastogenesis induced by supernatants from B. abortus-infected B cells. The results presented here shed light on how the interactions of B. abortus with B cells may have a role in the pathogenesis of brucellar osteoarticular disease. Copyright © 2016 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  9. Differential programming of B cells in AID deficient mice.

    Directory of Open Access Journals (Sweden)

    Marc A Hogenbirk

    Full Text Available The Aicda locus encodes the activation induced cytidine deaminase (AID and is highly expressed in germinal center (GC B cells to initiate somatic hypermutation (SHM and class switch recombination (CSR of immunoglobulin (Ig genes. Besides these Ig specific activities in B cells, AID has been implicated in active DNA demethylation in non-B cell systems. We here determined a potential role of AID as an epigenetic eraser and transcriptional regulator in B cells. RNA-Seq on different B cell subsets revealed that Aicda(-/- B cells are developmentally affected. However as shown by RNA-Seq, MethylCap-Seq, and SNP analysis these transcriptome alterations may not relate to AID, but alternatively to a CBA mouse strain derived region around the targeted Aicda locus. These unexpected confounding parameters provide alternative, AID-independent interpretations on genotype-phenotype correlations previously reported in numerous studies on AID using the Aicda(-/- mouse strain.

  10. Entry of Francisella tularensis into Murine B Cells: The Role of B Cell Receptors and Complement Receptors.

    Directory of Open Access Journals (Sweden)

    Lenka Plzakova

    Full Text Available Francisella tularensis, the etiological agent of tularemia, is an intracellular pathogen that dominantly infects and proliferates inside phagocytic cells but can be seen also in non-phagocytic cells, including B cells. Although protective immunity is known to be almost exclusively associated with the type 1 pathway of cellular immunity, a significant role of B cells in immune responses already has been demonstrated. Whether their role is associated with antibody-dependent or antibody-independent B cell functions is not yet fully understood. The character of early events during B cell-pathogen interaction may determine the type of B cell response regulating the induction of adaptive immunity. We used fluorescence microscopy and flow cytometry to identify the basic requirements for the entry of F. tularensis into B cells within in vivo and in vitro infection models. Here, we present data showing that Francisella tularensis subsp. holarctica strain LVS significantly infects individual subsets of murine peritoneal B cells early after infection. Depending on a given B cell subset, uptake of Francisella into B cells is mediated by B cell receptors (BCRs with or without complement receptor CR1/2. However, F. tularensis strain FSC200 ΔiglC and ΔftdsbA deletion mutants are defective in the ability to enter B cells. Once internalized into B cells, F. tularensis LVS intracellular trafficking occurs along the endosomal pathway, albeit without significant multiplication. The results strongly suggest that BCRs alone within the B-1a subset can ensure the internalization process while the BCRs on B-1b and B-2 cells need co-signaling from the co receptor containing CR1/2 to initiate F. tularensis engulfment. In this case, fluidity of the surface cell membrane is a prerequisite for the bacteria's internalization. The results substantially underline the functional heterogeneity of B cell subsets in relation to F. tularensis.

  11. Anti-B cell antibody therapies for inflammatory rheumatic diseases

    DEFF Research Database (Denmark)

    Faurschou, Mikkel; Jayne, David R W

    2014-01-01

    Several monoclonal antibodies targeting B cells have been tested as therapeutics for inflammatory rheumatic diseases. We review important observations from randomized clinical trials regarding the efficacy and safety of anti-B cell antibody-based therapies for rheumatoid arthritis, systemic lupus...... and functions in rheumatic disorders. Future studies should also evaluate how to maintain disease control by means of conventional and/or biologic immunosuppressants after remission-induction with anti-B cell antibodies....

  12. Leukemia - B-Cell Prolymphocytic Leukemia and Hairy Cell Leukemia

    Science.gov (United States)

    ... Leukemia - B-cell Prolymphocytic Leukemia and Hairy Cell Leukemia Introduction Statistics Risk Factors Symptoms and Signs Diagnosis Stages Treatment Options About Clinical Trials Latest Research ...

  13. B cells as a target of immune modulation

    Directory of Open Access Journals (Sweden)

    Hawker Kathleen

    2009-01-01

    Full Text Available B cells have recently been identified as an integral component of the immune system; they play a part in autoimmunity through antigen presentation, antibody secretion, and complement activation. Animal models of multiple sclerosis (MS suggest that myelin destruction is partly mediated through B cell activation (and plasmablasts. MS patients with evidence of B cell involvement, as compared to those without, tend to have a worse prognosis. Finally, the significant decrease in new gadolinium-enhancing lesions, new T2 lesions, and relapses in MS patients treated with rituximab (a monoclonal antibody against CD20 on B cells leads us to the conclusion that B cells play an important role in MS and that immune modulation of these cells may ameliorate the disease. This article will explore the role of B cells in MS and the rationale for the development of B cell-targeted therapeutics. MS is an immune-mediated disease that affects over 2 million people worldwide and is the number one cause of disability in young patients. Most therapeutic targets have focused on T cells; however, recently, the focus has shifted to the role of B cells in the pathogenesis of MS and the potential of B cells as a therapeutic target.

  14. 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.

  15. Expression levels of hsc70 and hsp60 are developmentally regulated during B-cell maturation and not associated to childhood c-ALL at presentation or relapse

    DEFF Research Database (Denmark)

    Wehner, Peder Skov; Nielsen, Bendt; Hokland, Marianne

    2003-01-01

    ) or heat shock protein 60 (hsp60) contribute to B-cell differentiation and leukemogenesis. We compared the expression of these hsps in normal peripheral blood (PB) CD19+ B-cells, in pediatric bone marrow (BM) CD19+ CD10+ B-cell precursors (BCPs) from normal donors, and in BCPs from common acute......Heat shock proteins are potent regulators of apoptosis, and so they may also be involved in normal cellular differentiation and cancerogenesis. We used quantitative two-dimensional gel electrophoresis for determining whether either the constitutive chaperonic heat shock cognate protein 70 (hsc70...

  16. Molecular mechanism of immunoglobulin V-region diversification regulated by transcription and RNA metabolism in antigen-driven B cells.

    Science.gov (United States)

    Sakaguchi, N; Maeda, K; Kuwahara, K

    2011-06-01

    The immune system produces specific antibodies (Ab) against any antigens (Ag) of exogenous and endogenous origins with a diverse repertoire of V-region specificities. The primary V-region repertoire is created by the rearrangement of immunoglobulin (Ig) V-region, D- and J-segments with the insertion of N- and P-sequences during early B cell differentiation. Recent studies revealed that secondary diversification of the IgV-region generated in the peripheral lymphoid organs plays a critical role in the generation of effective Ab production for protection from various pathogens. Naïve B cells that react with Ags initiate proliferation and differentiation in the follicular region and create the germinal centres (GCs), where activation-induced cytidine deaminase (AID)-dependent IgV-region somatic hypermutation (SHM) and class-switch recombination generate high-affinity and class-switched mature Ag-specific B cells. Our studies have discovered a 210-kDa nuclear protein, named GC-associated nuclear protein (GANP) that is up-regulated in GC B cells during the T cell-dependent (TD) immune responses. By studying mice with mutant forms of the ganp gene, we demonstrated that GANP is essential for the generation of high-affinity B cells against TD-Ag by affecting SHM at the IgV-regions. GANP is associated with AID in the cytoplasm and the GANP/AID complex is recruited to the nucleus, specifically, the chromatin, and targeted selectively to the IgV-region gene in B cells. GANP augments the access of AID towards IgV-regions in B cells. Here, we review the role of GANP in acquired immunity through the detailed analysis of the molecular mechanism generating SHM specifically at IgV-regions in B cells. © 2011 The Authors. Scandinavian Journal of Immunology © 2011 Blackwell Publishing Ltd.

  17. 1,25-dihydroxyvitamin D{sub 3} impairs NF-{kappa}B activation in human naive B cells

    Energy Technology Data Exchange (ETDEWEB)

    Geldmeyer-Hilt, Kerstin, E-mail: kerstin.hilt@charite.de [Allergie-Centrum-Charite, CCM, Klinik fuer Dermatologie und Allergologie, Charite - Universitaetsmedizin Berlin, Chariteplatz 1, 10117 Berlin (Germany); Heine, Guido, E-mail: guido.heine@charite.de [Allergie-Centrum-Charite, CCM, Klinik fuer Dermatologie und Allergologie, Charite - Universitaetsmedizin Berlin, Chariteplatz 1, 10117 Berlin (Germany); Deutsches Rheuma-Forschungszentrum Berlin, Chariteplatz 1, 10117 Berlin (Germany); Hartmann, Bjoern, E-mail: bjoern.hartmann@charite.de [Allergie-Centrum-Charite, CCM, Klinik fuer Dermatologie und Allergologie, Charite - Universitaetsmedizin Berlin, Chariteplatz 1, 10117 Berlin (Germany); Baumgrass, Ria, E-mail: baumgrass@drfz.de [Deutsches Rheuma-Forschungszentrum Berlin, Chariteplatz 1, 10117 Berlin (Germany); Radbruch, Andreas, E-mail: radbruch@drfz.de [Deutsches Rheuma-Forschungszentrum Berlin, Chariteplatz 1, 10117 Berlin (Germany); Worm, Margitta, E-mail: margitta.worm@charite.de [Allergie-Centrum-Charite, CCM, Klinik fuer Dermatologie und Allergologie, Charite - Universitaetsmedizin Berlin, Chariteplatz 1, 10117 Berlin (Germany)

    2011-04-22

    Highlights: {yields} In naive B cells, VDR activation by calcitriol results in reduced NF-{kappa}B p105 and p50 protein expression. {yields} Ligating the VDR with calcitriol causes reduced nuclear translocation of NF-{kappa}B p65. {yields} Reduced nuclear amount of p65 after calcitriol incubation results in reduced binding of p65 on the p105 promoter. {yields} Thus, vitamin D receptor signaling may reduce or prevent activation of B cells and unwanted immune responses, e.g. in IgE dependent diseases such as allergic asthma. -- Abstract: 1{alpha},25-dihydroxyvitamin D{sub 3} (calcitriol), the bioactive metabolite of vitamin D, modulates the activation and inhibits IgE production of anti-CD40 and IL-4 stimulated human peripheral B cells. Engagement of CD40 results in NF-{kappa}B p50 activation, which is essential for the class switch to IgE. Herein, we investigated by which mechanism calcitriol modulates NF-{kappa}B mediated activation of human naive B cells. Naive B cells were predominantly targeted by calcitriol in comparison with memory B cells as shown by pronounced induction of the VDR target gene cyp24a1. Vitamin D receptor activation resulted in a strongly reduced p105/p50 protein and mRNA expression in human naive B cells. This effect is mediated by impaired nuclear translocation of p65 and consequently reduced binding of p65 to its binding site in the p105 promoter. Our data indicate that the vitamin D receptor reduces NF-{kappa}B activation by interference with NF-{kappa}B p65 and p105. Thus, the vitamin D receptor inhibits costimulatory signal transduction in naive B cells, namely by reducing CD40 signaling.

  18. 1,25-dihydroxyvitamin D3 impairs NF-κB activation in human naive B cells

    International Nuclear Information System (INIS)

    Geldmeyer-Hilt, Kerstin; Heine, Guido; Hartmann, Bjoern; Baumgrass, Ria; Radbruch, Andreas; Worm, Margitta

    2011-01-01

    Highlights: → In naive B cells, VDR activation by calcitriol results in reduced NF-κB p105 and p50 protein expression. → Ligating the VDR with calcitriol causes reduced nuclear translocation of NF-κB p65. → Reduced nuclear amount of p65 after calcitriol incubation results in reduced binding of p65 on the p105 promoter. → Thus, vitamin D receptor signaling may reduce or prevent activation of B cells and unwanted immune responses, e.g. in IgE dependent diseases such as allergic asthma. -- Abstract: 1α,25-dihydroxyvitamin D 3 (calcitriol), the bioactive metabolite of vitamin D, modulates the activation and inhibits IgE production of anti-CD40 and IL-4 stimulated human peripheral B cells. Engagement of CD40 results in NF-κB p50 activation, which is essential for the class switch to IgE. Herein, we investigated by which mechanism calcitriol modulates NF-κB mediated activation of human naive B cells. Naive B cells were predominantly targeted by calcitriol in comparison with memory B cells as shown by pronounced induction of the VDR target gene cyp24a1. Vitamin D receptor activation resulted in a strongly reduced p105/p50 protein and mRNA expression in human naive B cells. This effect is mediated by impaired nuclear translocation of p65 and consequently reduced binding of p65 to its binding site in the p105 promoter. Our data indicate that the vitamin D receptor reduces NF-κB activation by interference with NF-κB p65 and p105. Thus, the vitamin D receptor inhibits costimulatory signal transduction in naive B cells, namely by reducing CD40 signaling.

  19. Genetic alterations in B-cell non-Hodgkin's lymphoma

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    Magić Zvonko

    2005-01-01

    Full Text Available Background. Although the patients with diagnosed B-NHL are classified into the same disease stage on the basis of clinical, histopathological, and immunological parameters, they respond significantly different to the applied treatment. This points out the possibility that within the same group of lymphoma there are different diseases at molecular level. For that reason many studies deal with the detection of gene alterations in lymphomas to provide a better framework for diagnosis and treatment of these hematological malignancies. Aim. To define genetic alterations in the B-NHL with highest possibilities for diagnostic purposes and molecular detection of MRD. Methods. Formalin fixed and paraffin embedded lymph node tissues from 45 patients were examined by different PCR techniques for the presence of IgH and TCR γ gene rearrangement; K-ras and H-ras mutations; c-myc amplification and bcl-2 translocation. There were 34 cases of B-cell non-Hodgkin’s lymphoma (B-NHL, 5 cases of T-cell non-Hodgkin’s lymphoma (T-NHL and 6 cases of chronic lymphadenitis (CL. The mononuclear cell fraction of the peripheral blood of 12 patients with B-NHL was analyzed for the presence of monoclonality at the time of diagnosis and in 3 to 6 months time intervals after an autologous bone marrow transplantation (BMT. Results. The monoclonality of B-lymphocytes, as evidenced by DNA fragment length homogeneity, was detected in 88 % (30/34 of B-NHL, but never in CL, T-NHL, or in normal PBL. Bcl-2 translocation was detected in 7/31 (22.6% B-NHL specimens, c-myc amplification 9/31 (29%, all were more than doubled, K-ras mutations in 1/31 (3.23% and H-ras mutations in 2/31 (6.45% of the examined B-NHL samples. In the case of LC and normal PBL, however, these gene alterations were not detected. All the patients (12 with B-NHL had dominant clone of B-lymphocyte in the peripheral blood at the time of diagnosis while only in 2 of 12 patients MRD was detected 3 or 6 months after

  20. Atypical memory B cells in human chronic infectious diseases: An interim report.

    Science.gov (United States)

    Portugal, Silvia; Obeng-Adjei, Nyamekye; Moir, Susan; Crompton, Peter D; Pierce, Susan K

    2017-11-01

    Immunological memory is a remarkable phenomenon in which survival of an initial infection by a pathogen leads to life-long protection from disease upon subsequent exposure to that same pathogen. For many infectious diseases, long-lived protective humoral immunity is induced after only a single infection in a process that depends on the generation of memory B cells (MBCs) and long-lived plasma cells. However, over the past decade it has become increasingly evident that many chronic human infectious diseases to which immunity is not readily established, including HIV-AIDS, malaria and TB, are associated with fundamental alterations in the composition and functionality of MBC compartments. A common feature of these diseases appears to be a large expansion of what have been termed exhausted B cells, tissue-like memory B cells or atypical memory B cells (aMBCs) that, for simplicity's sake, we refer to here as aMBCs. It has been suggested that chronic immune activation and inflammation drive the expansion of aMBCs and that in some way aMBCs contribute to deficiencies in the acquisition of immunity in chronic infectious diseases. Although aMBCs are heterogeneous both within individuals and between diseases, they have several features in common including low expression of the cell surface markers that define classical MBCs in humans including CD21 and CD27 and high expression of genes not usually expressed by classical MBCs including T-bet, CD11c and a variety of inhibitory receptors, notably members of the FcRL family. Another distinguishing feature is their greatly diminished ability to be stimulated through their B cell receptors to proliferate, secrete cytokines or produce antibodies. In this review, we describe our current understanding of the phenotypic markers of aMBCs, their specificity in relation to the disease-causing pathogen, their functionality, the drivers of their expansion in chronic infections and their life span. We briefly summarize the features of a

  1. B-cell-mediated strategies to fight chronic allograft rejection

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    Ali H Dalloul

    2013-12-01

    Full Text Available Solid organs have been transplanted for decades. Since the improvement in graft selection and in medical and surgical procedures, the likelihood of graft function after one year is now close to 90%. Nonetheless even well-matched recipients continue to need medications for the rest of their lives hence adverse side effects and enhanced morbidity. Understanding Immune rejection mechanisms, is of increasing importance since the greater use of living-unrelated donors and genetically unmatched individuals. Chronic rejection is devoted to T-cells, however the role of B-cells in rejection has been appreciated recently by the observation that B-cell depletion improve graft survival. By contrast however, B-cells can be beneficial to the grafted tissue. This protective effect is secondary to either the secretion of protective antibodies or the induction of B-cells that restrain excessive inflammatory responses, chiefly by local provision of IL-10, or inhibit effector T-cells by direct cellular interactions. As a proof of concept B-cell-mediated infectious transplantation tolerance could be achieved in animal models, and evidence emerged that the presence of such B-cells in transplanted patients correlate with a favorable outcome. Among these populations, regulatory B-cells constitute a recently described population. These cells may develop as a feedback mechanism to prevent uncontrolled reactivity to antigens and inflammatory stimuli. The difficult task for the clinician, is to quantify the respective ratios and functions of tolerant vs effector B-cells within a transplanted organ, at a given time point in order to modulate B-cell-directed therapy. Several receptors at the B-cell membrane as well as signaling molecules, can now be targeted for this purpose. Understanding the temporal expansion of regulatory B-cells in grafted patients and the stimuli that activate them will help in the future to implement specific strategies aimed at fighting chronic

  2. How B cells influence bone biology in health and disease.

    Science.gov (United States)

    Horowitz, Mark C; Fretz, Jackie A; Lorenzo, Joseph A

    2010-09-01

    It is now well established that important regulatory interactions occur between the cells in the hematopoietic, immune and skeletal systems (osteoimmunology). B lymphocytes (B cells) are responsible for the generation and production of antibodies or immunoglobulins in the body. Together with T cells these lymphocytes comprise the adaptive immune system, which allows an individual to develop specific responses to an infection and retain memory of that infection, allowing for a faster and more robust response if that same infection occurs again. In addition to this immune function, B cells have a close and multifaceted relationship with bone cells. B cells differentiate from hematopoietic stem cells (HSCs) in supportive niches found on endosteal bone surfaces. Cells in the osteoblast lineage support HSC and B cell differentiation in these niches. B cell differentiation is regulated, at least in part, by a series of transcription factors that function in a temporal manner. While these transcription factors are required for B cell differentiation, their loss causes profound changes in the bone phenotype. This is due, in part, to the close relationship between macrophage/osteoclast and B cell differentiation. Cross talk between B cells and bone cells is reciprocal with defects in the RANKL-RANK, OPG signaling axis resulting in altered bone phenotypes. While the role of B cells during normal bone remodeling appears minimal, activated B cells play an important role in many inflammatory diseases with associated bony changes. This review examines the relationship between B cells and bone cells and how that relationship affects the skeleton and hematopoiesis during health and disease. Copyright 2010 Elsevier Inc. All rights reserved.

  3. Tissue-specific B-cell dysfunction and generalized memory B-cell loss during acute SIV infection.

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    Sandrine Peruchon

    Full Text Available BACKGROUND: Primary HIV-infected patients display severe and irreversible damage to different blood B-cell subsets which is not restored by highly efficient anti-retroviral therapy (HAART. Because longitudinal investigations of primary HIV-infection is limited by the availability of lymphoid organs, we studied the tissue-specific B-cell dysfunctions in acutely simian immunodeficiency virus (SIV mac251-infected Cynomolgus macaques. METHODS AND FINDINGS: Experiments were performed on three groups of macaques infected for 14, 21 or 28 days and on three groups of animals treated with HAART for two-weeks either initiated at 4 h, 7 or 14 days post-infection (p.i.. We have simultaneously compared changes in B-cell phenotypes and functions and tissue organization of B-cell areas in various lymphoid organs. We showed that SIV induced a steady decline in SIgG-expressing memory (SIgD(-CD27(+ B-cells in spleen and lymph nodes during the first 4 weeks of infection, concomitant to selective homing/sequestration of B-cells to the small intestine and spleen. SIV non-specific Ig production was transiently increased before D14p.i., whereas SIV-specific Ig production was only detectable after D14p.i., coinciding with the presence of CD8(+ T-cells and IgG-expressing plasma cells within germinal centres. Transient B-cell apoptosis on D14p.i. and commitment to terminal differentiation contributed to memory B-cell loss. HAART abrogated B-cell apoptosis, homing to the small intestine and SIV-specific Ig production but had minimal effect on early Ig production, increased B-cell proportions in spleen and loss of memory B-cells. Therefore, virus-B-cell interactions and SIV-induced inflammatory cytokines may differently contribute to early B-cell dysfunction and impaired SIV/HIV-specific antibody response. CONCLUSIONS: These data establish tissue-specific impairments in B-cell trafficking and functions and a generalized and steady memory B-cell loss in secondary lymphoid

  4. Ku70 is required for late B cell development and immunoglobulin heavy chain class switching.

    Science.gov (United States)

    Manis, J P; Gu, Y; Lansford, R; Sonoda, E; Ferrini, R; Davidson, L; Rajewsky, K; Alt, F W

    1998-06-15

    Immunoglobulin (Ig) heavy chain (HC) class switch recombination (CSR) is a late B cell process that involves intrachromosomal DNA rearrangement. Ku70 and Ku80 form a DNA end-binding complex required for DNA double strand break repair and V(D)J recombination. Ku70(-/-) (K70T) mice, like recombination activating gene (RAG)-1- or RAG-2-deficient (R1T or R2T) mice, have impaired B and T cell development at an early progenitor stage, which is thought to result at least in part from defective V(D)J recombination (Gu, Y., K.J. Seidl, G.A. Rathbun, C. Zhu, J.P. Manis, N. van der Stoep, L. Davidson, H.L. Cheng, J.M. Sekiguchi, K. Frank, et al. 1997. Immunity. 7:653-665; Ouyang, H., A. Nussenzweig, A. Kurimasa, V.C. Soares, X. Li, C. Cordon-Cardo, W. Li, N. Cheong, M. Nussenzweig, G. Iliakis, et al. 1997. J. Exp. Med. 186:921-929). Therefore, to examine the potential role of Ku70 in CSR, we generated K70T mice that carry a germline Ig HC locus in which the JH region was replaced with a functionally rearranged VH(D)JH and Ig lambda light chain transgene (referred to as K70T/HL mice). Previously, we have shown that B cells from R1T or R2T mice carrying these rearranged Ig genes (R1T/HL or R2T/HL mice) can undergo CSR to IgG isotypes (Lansford, R., J. Manis, E. Sonoda, K. Rajewsky, and F. Alt. 1998. Int. Immunol. 10:325-332). K70T/HL mice had significant numbers of peripheral surface IgM+ B cells, which generated serum IgM levels similar to those of R2T/HL mice. However, in contrast to R2T/HL mice, K70T/HL mice had no detectable serum IgG isotypes. In vitro culture of K70T/HL B cells with agents that induce CSR in normal or R2T/HL B cells did lead to the induction of germline CH transcripts, indicating that initial signaling pathways for CSR were intact in K70T/HL cells. However, treatment with such agents did not lead to detectable CSR by K70T/HL B cells, and instead, led to cell death within 72 h. We conclude that Ku70 is required for the generation of B cells that have

  5. Common variable immunodeficiency in horses is characterized by B cell depletion in primary and secondary lymphoid tissues.

    Science.gov (United States)

    Flaminio, M Julia B F; Tallmadge, Rebecca L; Salles-Gomes, Cristina O M; Matychak, Mary Beth

    2009-01-01

    Common variable immunodeficiency (CVID) in horse patients is characterized by late-onset B cell lymphopenia or depletion, hypo- or agammaglobulinemia, impaired humoral response to tetanus toxoid vaccination, and recurrent fevers and bacterial infections. This study describes the clinical and immunologic findings of 14 affected horses (average age 10.7 +/- 4.4 years) of both genders (six females, eight males) and different breeds (eight Thoroughbreds, four Quarter Horses, one Warmblood, one Pony). Serial immunological testing in peripheral blood revealed persistent, severe B cell lymphopenia (mean 1.3 +/- 2.3% positive cells) in all patients. Serum IgG (range horses. Serum IgA concentrations declined with time. Histopathology and immunohistochemistry revealed absence of lymphoid follicles and B cells in primary and secondary lymphoid tissues. CVID is a cause of recurrent pneumonia, septicemia, and meningitis in adult horses and has a grave prognosis for clinical management and survival.

  6. Affinity isolation of antigen-specific circulating B cells for generation of phage display-derived human monoclonal antibodies

    DEFF Research Database (Denmark)

    Ditzel, Henrik

    2009-01-01

    A method is described for affinity isolation of antigen-specific circulating B cells of interest for subsequent generation of immune antibody phage display libraries. This approach should overcome the problem of low yields of monoclonal antibodies of interest in the libraries generated from...... peripheral blood lymphocytes caused by the low abundance of antigen-specific B cells in the circulation. The preselection of B cells is based on the specificity of the surface Ig receptor and is accomplished using the antigen of interest conjugated to magnetic beads. This method should significantly increase...... the frequency of antibody phage particles of interest in the library and allow for efficient isolation monoclonal antibodies with the predefined specificity....

  7. DNA breaks early in replication in B cell cancers

    Science.gov (United States)

    Research by scientists at the NCI has identified a new class of DNA sites in cells that break early in the replication process. They found that these break sites correlate with damage often seen in B cell cancers, such as diffuse large B cell lymphoma.

  8. Murid herpesvirus-4 exploits dendritic cells to infect B cells.

    Directory of Open Access Journals (Sweden)

    Miguel Gaspar

    2011-11-01

    Full Text Available Dendritic cells (DCs play a central role in initiating immune responses. Some persistent viruses infect DCs and can disrupt their functions in vitro. However, these viruses remain strongly immunogenic in vivo. Thus what role DC infection plays in the pathogenesis of persistent infections is unclear. Here we show that a persistent, B cell-tropic gamma-herpesvirus, Murid Herpesvirus-4 (MuHV-4, infects DCs early after host entry, before it establishes a substantial infection of B cells. DC-specific virus marking by cre-lox recombination revealed that a significant fraction of the virus latent in B cells had passed through a DC, and a virus attenuated for replication in DCs was impaired in B cell colonization. In vitro MuHV-4 dramatically altered the DC cytoskeleton, suggesting that it manipulates DC migration and shape in order to spread. MuHV-4 therefore uses DCs to colonize B cells.

  9. 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

  10. Suppression of circulating IgD+CD27+ memory B cells in infants living in a malaria-endemic region of Kenya.

    Science.gov (United States)

    Asito, Amolo S; Piriou, Erwan; Jura, Walter G Z O; Ouma, Collins; Odada, Peter S; Ogola, Sidney; Fiore, Nancy; Rochford, Rosemary

    2011-12-13

    Plasmodium falciparum infection leads to alterations in B cell subset distribution. During infancy, development of peripheral B cell subsets is also occurring. However, it is unknown if infants living a malaria endemic region have alterations in B cell subsets that is independent of an age effect. To evaluate the impact of exposure to P. falciparum on B cell development in infants, flow cytometry was used to analyse the distribution and phenotypic characteristic of B cell subsets in infant cohorts prospectively followed at 12, 18 and 24 months from two geographically proximate regions in western Kenya with divergent malaria exposure i.e. Kisumu (malaria-endemic, n = 24) and Nandi (unstable malaria transmission, n = 21). There was significantly higher frequency and absolute cell numbers of CD19+ B cells in Kisumu relative to Nandi at 12(p = 0.0440), 18(p = 0.0210) and 24 months (p = 0.0493). No differences were observed between the infants from the two sites in frequencies of naïve B cells (IgD+CD27-) or classical memory B cells (IgD-CD27+). However, immature transitional B cells (CD19+CD10+CD34-) were higher in Kisumu relative to Nandi at all three ages. In contrast, the levels of non-class switched memory B cells (CD19+IgD+CD27+) were significantly lower overall in Kisumu relative to Nandi at significantly at 12 (p = 0.0144), 18 (p = 0.0013) and 24 months (p = 0.0129). These data suggest that infants living in malaria endemic regions have altered B cell subset distribution. Further studies are needed to understand the functional significance of these changes and long-term impact on ability of these infants to develop antibody responses to P. falciparum and heterologous infections.

  11. Suppression of circulating IgD+CD27+ memory B cells in infants living in a malaria-endemic region of Kenya

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    Asito Amolo S

    2011-12-01

    Full Text Available Abstract Background Plasmodium falciparum infection leads to alterations in B cell subset distribution. During infancy, development of peripheral B cell subsets is also occurring. However, it is unknown if infants living a malaria endemic region have alterations in B cell subsets that is independent of an age effect. Methods To evaluate the impact of exposure to P. falciparum on B cell development in infants, flow cytometry was used to analyse the distribution and phenotypic characteristic of B cell subsets in infant cohorts prospectively followed at 12, 18 and 24 months from two geographically proximate regions in western Kenya with divergent malaria exposure i.e. Kisumu (malaria-endemic, n = 24 and Nandi (unstable malaria transmission, n = 21. Results There was significantly higher frequency and absolute cell numbers of CD19+ B cells in Kisumu relative to Nandi at 12(p = 0.0440, 18(p = 0.0210 and 24 months (p = 0.0493. No differences were observed between the infants from the two sites in frequencies of naïve B cells (IgD+CD27- or classical memory B cells (IgD-CD27+. However, immature transitional B cells (CD19+CD10+CD34- were higher in Kisumu relative to Nandi at all three ages. In contrast, the levels of non-class switched memory B cells (CD19+IgD+CD27+ were significantly lower overall in Kisumu relative to Nandi at significantly at 12 (p = 0.0144, 18 (p = 0.0013 and 24 months (p = 0.0129. Conclusions These data suggest that infants living in malaria endemic regions have altered B cell subset distribution. Further studies are needed to understand the functional significance of these changes and long-term impact on ability of these infants to develop antibody responses to P. falciparum and heterologous infections.

  12. Age-Associated Decline in Thymic B Cell Expression of Aire and Aire-Dependent Self-Antigens

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    Sergio Cepeda

    2018-01-01

    Full Text Available Although autoimmune disorders are a significant source of morbidity and mortality in older individuals, the mechanisms governing age-associated increases in susceptibility remain incompletely understood. Central T cell tolerance is mediated through presentation of self-antigens by cells constituting the thymic microenvironment, including epithelial cells, dendritic cells, and B cells. Medullary thymic epithelial cells (mTECs and B cells express distinct cohorts of self-antigens, including tissue-restricted self-antigens (TRAs, such that developing T cells are tolerized to antigens from peripheral tissues. We find that expression of the TRA transcriptional regulator Aire, as well as Aire-dependent genes, declines with age in thymic B cells in mice and humans and that cell-intrinsic and cell-extrinsic mechanisms contribute to the diminished capacity of peripheral B cells to express Aire within the thymus. Our findings indicate that aging may diminish the ability of thymic B cells to tolerize T cells, revealing a potential mechanistic link between aging and autoimmunity.

  13. CCR3 expression induced by IL-2 and IL-4 functioning as a death receptor for B cells

    DEFF Research Database (Denmark)

    Jinquan, Tan; Jacobi, Henrik H; Jing, Chen

    2003-01-01

    We report that CCR3 is not expressed on freshly isolated peripheral and germinal B cells, but is up-regulated after stimulation with IL-2 and IL-4 (approximately 98% CCR3(+)). Ligation of CCR3 by eotaxin/chemokine ligand (CCL) 11 induces apoptosis in IL-2- and IL-4-stimulated primary CD19......-4, and eotaxin/CCL11 (88% CD95 and 84% CD95L). We therefore propose that ligation of such newly induced CCR3 on peripheral and germinal B cells by eotaxin/CCL11 leads to the enhanced levels of CD95 and CD95L expression. Ligation of CD95 by its CD95L expressed on neigboring B cells triggers relevant....... Interaction between CCR3 and eotaxin/CCL11 may, besides promoting allergic reactions, drive activated B cells to apoptosis, thereby reducing levels of Ig production, including IgE, and consequently limit the development of the humoral immune response. The apoptotic action of eotaxin/CCL11 suggests...

  14. Relapsed Diffuse Large B-Cell Lymphoma Treated by Reduced-Intensity Allogeneic Stem Cell Transplantation with Donor Lymphocyte Infusion

    International Nuclear Information System (INIS)

    Chudhry, Q.N.; Ahmed, P.; Ullah, K.; Satti, T.M.; Raza, S.; Mehmood, S.K.; Akram, M.; Ahmed, S.

    2010-01-01

    A 42 years old male with relapsed diffuse large B-cell lymphoma was given second-line chemotherapy followed by reduced intensity allogeneic stem cell transplantation from HLA matched brother. Twelve weeks post transplant, his disease relapsed evidenced by the appearance of lymphoma cells in the peripheral blood and declining donor chimerism. Donor lymphocyte infusion was given that induced complete lymphoma remission. The patient is well 3 years post transplant with his disease in complete remission. (author)

  15. Dynamics of Dengue Virus (DENV)-Specific B Cells in the Response to DENV Serotype 1 Infections, Using Flow Cytometry With Labeled Virions.

    Science.gov (United States)

    Woda, Marcia; Friberg, Heather; Currier, Jeffrey R; Srikiatkhachorn, Anon; Macareo, Louis R; Green, Sharone; Jarman, Richard G; Rothman, Alan L; Mathew, Anuja

    2016-10-01

    The development of reagents to identify and characterize antigen-specific B cells has been challenging. We recently developed Alexa Fluor-labeled dengue viruses (AF DENVs) to characterize antigen-specific B cells in the peripheral blood of DENV-immune individuals. In this study, we used AF DENV serotype 1 (AF DENV-1) together with AF DENV-2 on peripheral blood mononuclear cells (PBMCs) from children in Thailand with acute primary or secondary DENV-1 infections to analyze the phenotypes of antigen-specific B cells that reflected their exposure or clinical diagnosis. DENV serotype-specific and cross-reactive B cells were identified in PBMCs from all subjects. Frequencies of AF DENV(+) class-switched memory B cells (IgD(-)CD27(+) CD19(+) cells) reached up to 8% during acute infection and early convalescence. AF DENV-labeled B cells expressed high levels of CD27 and CD38 during acute infection, characteristic of plasmablasts, and transitioned into memory B cells (CD38(-)CD27(+)) at the early convalescent time point. There was higher activation of memory B cells early during acute secondary infection, suggesting reactivation from a previous DENV infection. AF DENVs reveal changes in the phenotype of DENV serotype-specific and cross-reactive B cells during and after natural DENV infection and could be useful in analysis of the response to DENV vaccination. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  16. Peripheral reactions

    International Nuclear Information System (INIS)

    Greiner, D.

    1978-01-01

    Peripheral collisions, that is, collisions involving a small amount of overlap of nuclear matter, are discussed including inclusive interactions, the magnitude of the peripheral cross section, fragmentation, a compilation of experiments and available data, limiting fragmentation, factorization, some models, fragment momentum distributions, and future research directions

  17. Comparison of EBV DNA viral load in whole blood, plasma, B-cells and B-cell culture supernatant.

    Science.gov (United States)

    Ouedraogo, David Eric; Bollore, Karine; Viljoen, Johannes; Foulongne, Vincent; Reynes, Jacques; Cartron, Guillaume; Vendrell, Jean-Pierre; Van de Perre, Philippe; Tuaillon, Edouard

    2014-05-01

    Epstein-Barr virus (EBV) genome quantitation in whole blood is used widely for therapeutic monitoring of EBV-associated disorders in immunosuppressed individuals and in patients with EBV-associated lymphoma. However, the most appropriate biological material to be used for EBV DNA quantitation remains a subject of debate. This study compare the detection rate and levels of EBV DNA from whole blood, plasma, enriched B-cells, and B-cell short-term culture supernatant using quantitative real-time PCR. Samples were collected from 33 subjects with either HIV infection or B-cell lymphoma. Overall, EBV DNA was detected in 100% of enriched B-cell samples, in 82% of B-cell culture supernatants, in 57% of plasma, and 42% of whole blood samples. A significant correlation for EBV viral load was found between enriched B-cell and B-cell culture supernatant material (ρ = 0.92; P cells (ρ = -0.02; P = 0.89), whole blood and plasma (ρ = 0.24; P = 0.24), or enriched B-cells and plasma (ρ = 0.08; P = 0.77). Testing of enriched B-cells appeared to be the most sensitive method for detection of EBV DNA as well as for exploration of the cellular reservoir. Quantitation of EBV DNA in plasma and B-cell culture supernatant may be of interest to assess EBV reactivation dynamics and response to treatment as well as to decipher EBV host-pathogen interactions in various clinical scenarios. © 2013 Wiley Periodicals, Inc.

  18. Imaging of iliopsoas compartment disease

    International Nuclear Information System (INIS)

    Rocher, L.; Saint Maurice, J.P.; Le Quen, O.; Bazille, A.; Miquel, A.; Frouge, C.; Blery, M.

    1997-01-01

    Infection, neoplastic involvement, and hemorrhage, are the most frequent pathologies that involve the ilio-psoas compartment. The extension from contiguous pathological structures and particularly digestive and urological organs, are often the origin of abscess formation or malignant tumours. The radiological findings including ultrasonography, CT, and magnetic resonance imaging, show a low specificity, which improves if the clinical history is known. The final diagnosis is confirmed by puncture or biopsy. (author)

  19. Fluctuations in Blood Marginal Zone B-Cell Frequencies May Reflect Migratory Patterns Associated with HIV-1 Disease Progression Status.

    Science.gov (United States)

    Gauvin, Julie; Chagnon-Choquet, Josiane; Poudrier, Johanne; Roger, Michel

    2016-01-01

    We have previously shown that overexpression of BLyS/BAFF was associated with increased relative frequencies of innate "precursor" marginal zone (MZ)-like B-cells in the blood of HIV-1-infected rapid and classic progressors. However, along with relatively normal BLyS/BAFF expression levels, these cells remain unaltered in elite-controllers (EC), rather, percentages of more mature MZ-like B-cells are decreased in the blood of these individuals. Fluctuations in frequencies of blood MZ-like B-cell populations may reflect migratory patterns associated with disease progression status, suggesting an important role for these cells in HIV-1 pathogenesis. We have therefore longitudinally measured plasma levels of B-tropic chemokines by ELISA-based technology as well as their ligands by flow-cytometry on blood B-cell populations of HIV-1-infected individuals with different rates of disease progression and uninfected controls. Migration potential of B-cell populations from these individuals were determined by chemotaxis assays. We found important modulations of CXCL13-CXCR5, CXCL12-CXCR4/CXCR7, CCL20-CCR6 and CCL25-CCR9 chemokine-axes and increased cell migration patterns in HIV progressors. Interestingly, frequencies of CCR6 expressing cells were significantly elevated within the precursor MZ-like population, consistent with increased migration in response to CCL20. Although we found little modulation of chemokine-axes in EC, cell migration was greater than that observed for uninfected controls, especially for MZ-like B-cells. Overall the immune response against HIV-1 may involve recruitment of MZ-like B-cells to peripheral sites. Moreover, our findings suggest that "regulated" attraction of these cells in a preserved BLyS/BAFF non-inflammatory environment, such as encountered in EC could be beneficial to the battle and even control of HIV.

  20. An allospecific murine T helper clone which can help both T and B cell responses in vitro and in vivo

    DEFF Research Database (Denmark)

    Crispe, I N; Gascoigne, N R; Owens, T

    1984-01-01

    . Here we describe an in vitro and in vivo study of this problem, using a Th clone, designated MTH-1. The clone carries the cell surface markers Thy-1 and L3T4a, but lacks Lyt-2. It recognizes a minor alloantigen shared by DBA/2, B10.D2 and NZB spleen cells, and such recognition is restricted by H-2Ed...... in the polyclonal activation and maturation of the B cells to secrete immunoglobulin; also, antigen-primed B cells are augmented in their in vivo synthesis of specific antibody to the Thy-1 X 1 alloantigen by around 10(5) MTH-1 cells. Taken together, these results suggest a single Th clone can help both B cells......Both B lymphocytes and cytotoxic T lymphocytes respond to signals from the T helper (Th) compartment, and such signals are mediated by a number of biochemically distinct factors. This raises the question whether help for B cells and T cells is a function of one or several different kinds of Th cell...

  1. Human Memory B Cells in Healthy Gingiva, Gingivitis, and Periodontitis.

    Science.gov (United States)

    Mahanonda, Rangsini; Champaiboon, Chantrakorn; Subbalekha, Keskanya; Sa-Ard-Iam, Noppadol; Rattanathammatada, Warattaya; Thawanaphong, Saranya; Rerkyen, Pimprapa; Yoshimura, Fuminobu; Nagano, Keiji; Lang, Niklaus P; Pichyangkul, Sathit

    2016-08-01

    The presence of inflammatory infiltrates with B cells, specifically plasma cells, is the hallmark of periodontitis lesions. The composition of these infiltrates in various stages of homeostasis and disease development is not well documented. Human tissue biopsies from sites with gingival health (n = 29), gingivitis (n = 8), and periodontitis (n = 21) as well as gingival tissue after treated periodontitis (n = 6) were obtained and analyzed for their composition of B cell subsets. Ag specificity, Ig secretion, and expression of receptor activator of NF-κB ligand and granzyme B were performed. Although most of the B cell subsets in healthy gingiva and gingivitis tissues were CD19(+)CD27(+)CD38(-) memory B cells, the major B cell component in periodontitis was CD19(+)CD27(+)CD38(+)CD138(+)HLA-DR(low) plasma cells, not plasmablasts. Plasma cell aggregates were observed at the base of the periodontal pocket and scattered throughout the gingiva, especially apically toward the advancing front of the lesion. High expression of CXCL12, a proliferation-inducing ligand, B cell-activating factor, IL-10, IL-6, and IL-21 molecules involved in local B cell responses was detected in both gingivitis and periodontitis tissues. Periodontitis tissue plasma cells mainly secreted IgG specific to periodontal pathogens and also expressed receptor activator of NF-κB ligand, a bone resorption cytokine. Memory B cells resided in the connective tissue subjacent to the junctional epithelium in healthy gingiva. This suggested a role of memory B cells in maintaining periodontal homeostasis. Copyright © 2016 by The American Association of Immunologists, Inc.

  2. Numerical treatment of compartment models

    International Nuclear Information System (INIS)

    Einarsson, B.

    1984-11-01

    This report describes and interactive program RADIO (Radioactive Decay Information Online) for studying the radioactive decay process, with applications to many ecological problems, but not necessarily involving radioactive processes. Starting with the compartment coefficients and initial values of the various compartments the problem is solved as a system of linear ordinary differential equations. The method of solution is the direct use of matrix exponentials or the backward differences method. A program INVERS is also available for the solution of the inverse problem, that is parameter estimation in a system of linear ordinary differential equations when the solution is available pointwise. The output can be printed on a line printer either from a result file or from the plot file, which of course also can be used to produce graphic output. The plot file is processed by the plotting program VISION or by the auxiliary printing program RADAR. Another file can be used for a later restart from the point of time where the previous computation was aborted or from an arbitrary point of time if the relevant starting information is available. This is useful in order to avoid the manual input of a compartment matrix if it is similar to one used before. When the program RADIO is run the user answers to the question asked by the program. The programs are written in Fortran 77 for the Digital Equipment VAX 11 with graphical presentation on a Tektronix 4010, and are available from the author. (Author)

  3. Compartment syndrome after total knee arthroplasty: regarding a clinical case

    Directory of Open Access Journals (Sweden)

    Ana Alexandra da Costa Pinheiro

    2015-08-01

    Full Text Available ABSTRACT Although compartment syndrome is a rare complication of total knee arthroplasty, it is one of the most devastating complications. It is defined as a situation of increased pressure within a closed osteofascial space that impairs the circulation and the functioning of the tissues inside this space, thereby leading to ischemia and tissue dysfunction. Here, a clinical case of a patient who was followed up in orthopedic outpatient consultations due to right gonarthrosis is presented. The patient had a history of arthroscopic meniscectomy and presented knee flexion of 10° before the operation, which consisted of total arthroplasty of the right knee. The operation seemed to be free from intercurrences, but the patient evolved with compartment syndrome of the ipsilateral leg after the operation. Since compartment syndrome is a true surgical emergency, early recognition and treatment of this condition through fasciotomy is crucial in order to avoid amputation, limb dysfunction, kidney failure and death. However, it may be difficult to make the diagnosis and cases may not be recognized if the cause of compartment syndrome is unusual or if the patient is under epidural analgesia and/or peripheral nerve block, which thus camouflages the main warning sign, i.e. disproportional pain. In addition, edema of the limb that underwent the intervention is common after total knee arthroplasty operations. This study presents a review of the literature and signals that the possible rarity of cases is probably due to failure to recognize this condition in a timely manner and to placing these patients in other diagnostic groups that are less likely, such as neuropraxia caused by using a tourniquet or peripheral nerve injury.

  4. B-cell lymphoma with Mott cell differentiation in two young adult dogs.

    Science.gov (United States)

    Stacy, Nicole I; Nabity, Mary B; Hackendahl, Nicole; Buote, Melanie; Ward, Jennifer; Ginn, Pamela E; Vernau, William; Clapp, William L; Harvey, John W

    2009-03-01

    Two young adult dogs with gastrointestinal signs were each found to have an intra-abdominal mass based on physical examination and diagnostic imaging. On exploratory laparotomy, small intestinal masses and mesenteric lymphadenopathy were found in both dogs; a liver mass was also found in dog 1. Cytologic and histologic examination of intestinal and liver masses and mesenteric lymph nodes revealed 2 distinct lymphoid cell populations: lymphoblasts and atypical Mott cells. With Romanowsky stains, the atypical Mott cells contained many discrete, clear to pale blue cytoplasmic inclusions consistent with Russell bodies that were positive by immunohistochemistry for IgM and CD79a in both dogs and for IgG in dog 2. The Mott cells and occasional lymphoblasts stained strongly positive with periodic acid-Schiff. Using flow cytometric immunophenotyping in dog 1, 60% of peripheral blood mononuclear cells and 85% of cells in an affected lymph node were positive for CD21, CD79a, IgM, and MCH II, indicative of B-cells. With electron microscopy, disorganized and dilated endoplasmic reticulum was seen in Mott cells in tumors from both dogs. Antigen receptor gene rearrangement analysis of lymph node and intestinal masses indicated a clonal B-cell population. Based on cell morphology, tissue involvement, and evidence for clonal B-cell proliferation, we diagnosed neoplasms involving Mott cells. To the authors' knowledge, this is the second report of Mott cell tumors or, more appropriately, B-cell lymphoma with Mott cell differentiation, in dogs. More complete characterization of this neoplasm requires further investigation of additional cases. This lymphoproliferative disease should be considered as a differential diagnosis for canine gastrointestinal tumors.

  5. Evaluation of Antigen-Conjugated Fluorescent Beads to Identify Antigen-Specific B Cells.

    Science.gov (United States)

    Correa, Isabel; Ilieva, Kristina M; Crescioli, Silvia; Lombardi, Sara; Figini, Mariangela; Cheung, Anthony; Spicer, James F; Tutt, Andrew N J; Nestle, Frank O; Karagiannis, Panagiotis; Lacy, Katie E; Karagiannis, Sophia N

    2018-01-01

    Selection of single antigen-specific B cells to identify their expressed antibodies is of considerable interest for evaluating human immune responses. Here, we present a method to identify single antibody-expressing cells using antigen-conjugated fluorescent beads. To establish this, we selected Folate Receptor alpha (FRα) as a model antigen and a mouse B cell line, expressing both the soluble and the membrane-bound forms of a human/mouse chimeric antibody (MOv18 IgG1) specific for FRα, as test antibody-expressing cells. Beads were conjugated to FRα using streptavidin/avidin-biotin bridges and used to select single cells expressing the membrane-bound form of anti-FRα. Bead-bound cells were single cell-sorted and processed for single cell RNA retrotranscription and PCR to isolate antibody heavy and light chain variable regions. Variable regions were then cloned and expressed as human IgG1/k antibodies. Like the original clone, engineered antibodies from single cells recognized native FRα. To evaluate whether antigen-coated beads could identify specific antibody-expressing cells in mixed immune cell populations, human peripheral blood mononuclear cells (PBMCs) were spiked with test antibody-expressing cells. Antigen-specific cells could comprise up to 75% of cells selected with antigen-conjugated beads when the frequency of the antigen-positive cells was 1:100 or higher. In PBMC pools, beads conjugated to recombinant antigens FRα and HER2 bound antigen-specific anti-FRα MOv18 and anti-HER2 Trastuzumab antibody-expressing cells, respectively. From melanoma patient-derived B cells selected with melanoma cell line-derived protein-coated fluorescent beads, we generated a monoclonal antibody that recognized melanoma antigen-coated beads. This approach may be further developed to facilitate analysis of B cells and their antibody profiles at the single cell level and to help unravel humoral immune repertoires.

  6. Evaluation of Antigen-Conjugated Fluorescent Beads to Identify Antigen-Specific B Cells

    Directory of Open Access Journals (Sweden)

    Isabel Correa

    2018-03-01

    Full Text Available Selection of single antigen-specific B cells to identify their expressed antibodies is of considerable interest for evaluating human immune responses. Here, we present a method to identify single antibody-expressing cells using antigen-conjugated fluorescent beads. To establish this, we selected Folate Receptor alpha (FRα as a model antigen and a mouse B cell line, expressing both the soluble and the membrane-bound forms of a human/mouse chimeric antibody (MOv18 IgG1 specific for FRα, as test antibody-expressing cells. Beads were conjugated to FRα using streptavidin/avidin-biotin bridges and used to select single cells expressing the membrane-bound form of anti-FRα. Bead-bound cells were single cell-sorted and processed for single cell RNA retrotranscription and PCR to isolate antibody heavy and light chain variable regions. Variable regions were then cloned and expressed as human IgG1/k antibodies. Like the original clone, engineered antibodies from single cells recognized native FRα. To evaluate whether antigen-coated beads could identify specific antibody-expressing cells in mixed immune cell populations, human peripheral blood mononuclear cells (PBMCs were spiked with test antibody-expressing cells. Antigen-specific cells could comprise up to 75% of cells selected with antigen-conjugated beads when the frequency of the antigen-positive cells was 1:100 or higher. In PBMC pools, beads conjugated to recombinant antigens FRα and HER2 bound antigen-specific anti-FRα MOv18 and anti-HER2 Trastuzumab antibody-expressing cells, respectively. From melanoma patient-derived B cells selected with melanoma cell line-derived protein-coated fluorescent beads, we generated a monoclonal antibody that recognized melanoma antigen-coated beads. This approach may be further developed to facilitate analysis of B cells and their antibody profiles at the single cell level and to help unravel humoral immune repertoires.

  7. Evaluation of Antigen-Conjugated Fluorescent Beads to Identify Antigen-Specific B Cells

    Science.gov (United States)

    Correa, Isabel; Ilieva, Kristina M.; Crescioli, Silvia; Lombardi, Sara; Figini, Mariangela; Cheung, Anthony; Spicer, James F.; Tutt, Andrew N. J.; Nestle, Frank O.; Karagiannis, Panagiotis; Lacy, Katie E.; Karagiannis, Sophia N.

    2018-01-01

    Selection of single antigen-specific B cells to identify their expressed antibodies is of considerable interest for evaluating human immune responses. Here, we present a method to identify single antibody-expressing cells using antigen-conjugated fluorescent beads. To establish this, we selected Folate Receptor alpha (FRα) as a model antigen and a mouse B cell line, expressing both the soluble and the membrane-bound forms of a human/mouse chimeric antibody (MOv18 IgG1) specific for FRα, as test antibody-expressing cells. Beads were conjugated to FRα using streptavidin/avidin-biotin bridges and used to select single cells expressing the membrane-bound form of anti-FRα. Bead-bound cells were single cell-sorted and processed for single cell RNA retrotranscription and PCR to isolate antibody heavy and light chain variable regions. Variable regions were then cloned and expressed as human IgG1/k antibodies. Like the original clone, engineered antibodies from single cells recognized native FRα. To evaluate whether antigen-coated beads could identify specific antibody-expressing cells in mixed immune cell populations, human peripheral blood mononuclear cells (PBMCs) were spiked with test antibody-expressing cells. Antigen-specific cells could comprise up to 75% of cells selected with antigen-conjugated beads when the frequency of the antigen-positive cells was 1:100 or higher. In PBMC pools, beads conjugated to recombinant antigens FRα and HER2 bound antigen-specific anti-FRα MOv18 and anti-HER2 Trastuzumab antibody-expressing cells, respectively. From melanoma patient-derived B cells selected with melanoma cell line-derived protein-coated fluorescent beads, we generated a monoclonal antibody that recognized melanoma antigen-coated beads. This approach may be further developed to facilitate analysis of B cells and their antibody profiles at the single cell level and to help unravel humoral immune repertoires. PMID:29628923

  8. B-Cell-Specific Diversion of Glucose Carbon Utilization Reveals a Unique Vulnerability in B Cell Malignancies.

    Science.gov (United States)

    Xiao, Gang; Chan, Lai N; Klemm, Lars; Braas, Daniel; Chen, Zhengshan; Geng, Huimin; Zhang, Qiuyi Chen; Aghajanirefah, Ali; Cosgun, Kadriye Nehir; Sadras, Teresa; Lee, Jaewoong; Mirzapoiazova, Tamara; Salgia, Ravi; Ernst, Thomas; Hochhaus, Andreas; Jumaa, Hassan; Jiang, Xiaoyan; Weinstock, David M; Graeber, Thomas G; Müschen, Markus

    2018-04-05

    B cell activation during normal immune responses and oncogenic transformation impose increased metabolic demands on B cells and their ability to retain redox homeostasis. While the serine/threonine-protein phosphatase 2A (PP2A) was identified as a tumor suppressor in multiple types of cancer, our genetic studies revealed an essential role of PP2A in B cell tumors. Thereby, PP2A redirects glucose carbon utilization from glycolysis to the pentose phosphate pathway (PPP) to salvage oxidative stress. This unique vulnerability reflects constitutively low PPP activity in B cells and transcriptional repression of G6PD and other key PPP enzymes by the B cell transcription factors PAX5 and IKZF1. Reflecting B-cell-specific transcriptional PPP-repression, glucose carbon utilization in B cells is heavily skewed in favor of glycolysis resulting in lack of PPP-dependent antioxidant protection. These findings reveal a gatekeeper function of the PPP in a broad range of B cell malignancies that can be efficiently targeted by small molecule inhibition of PP2A and G6PD. Copyright © 2018 Elsevier Inc. All rights reserved.

  9. Cloning of B cell-specific membrane tetraspanning molecule BTS possessing B cell proliferation-inhibitory function.

    Science.gov (United States)

    Suenaga, Tadahiro; Arase, Hisashi; Yamasaki, Sho; Kohno, Masayuki; Yokosuka, Tadashi; Takeuchi, Arata; Hattori, Takamichi; Saito, Takashi

    2007-11-01

    Lymphocyte proliferation is regulated by signals through antigen receptors, co-stimulatory receptors, and other positive and negative modulators. Several membrane tetraspanning molecules are also involved in the regulation of lymphocyte growth and death. We cloned a new B cell-specific tetraspanning (BTS) membrane molecule, which is similar to CD20 in terms of expression, structure and function. BTS is specifically expressed in the B cell line and its expression is increased after the pre-B cell stage. BTS is expressed in intracellular granules and on the cell surface. Overexpression of BTS in immature B cell lines induces growth retardation through inhibition of cell cycle progression and cell size increase without inducing apoptosis. This inhibitory function is mediated predominantly by the N terminus of BTS. The development of mature B cells is inhibited in transgenic mice expressing BTS, suggesting that BTS is involved in the in vivo regulation of B cells. These results indicate that BTS plays a role in the regulation of cell division and B cell growth.

  10. B-cell activating factor detected on both naïve and memory B cells in bullous pemphigoid.

    Science.gov (United States)

    Qian, Hua; Kusuhara, Masahiro; Li, Xiaoguang; Tsuruta, Daisuke; Tsuchisaka, Atsunari; Ishii, Norito; Koga, Hiroshi; Hayakawa, Taihei; Ohara, Koji; Karashima, Tadashi; Ohyama, Bungo; Ohata, Chika; Furumura, Minao; Hashimoto, Takashi

    2014-08-01

    B-cell activating factor (BAFF), an important immune regulatory cytokine, is involved in development of autoimmune diseases. Although BAFF is expressed in various cells, including dendritic cells (DCs) and monocytes, BAFF expression on B cells has not been well documented. In the present study, BAFF molecules on DCs and naïve and memory B cells in autoimmune bullous diseases, including pemphigus vulgaris, pemphigus foliaceus and bullous pemphigoid (BP), were analysed by flow cytometry. Compared with healthy controls (HC), BAFF expression on naïve and memory B cells increased significantly in BP. No difference in BAFF receptor expression in naïve and memory B cells was shown among all study groups. Furthermore, BAFF expression in both naïve and memory B cells of BP, but not HC, was detected by confocal microscopic analysis. These results implied that BAFF expressed by B cells may play a pathogenic role in autoimmune bullous diseases, particularly BP. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Beneficial Effects of cART Initiated during Primary and Chronic HIV-1 Infection on Immunoglobulin-Expression of Memory B-Cell Subsets.

    Directory of Open Access Journals (Sweden)

    Manuela Pogliaghi

    Full Text Available During HIV-1 infection the B-cell compartment undergoes profound changes towards terminal differentiation, which are only partially restored by antiretroviral therapy (cART.To investigate the impact of infection as early as during primary HIV-1 infection (PHI we assessed distribution of B-cell subsets in 19 PHI and 25 chronic HIV-1-infected (CHI individuals before and during 48 weeks of cART as compared to healthy controls (n = 23. We also analysed Immunoglobulin-expression of memory B-cell subsets to identify alterations in Immunoglobulin-maturation.Determination of B-cell subsets at baseline showed that total and Naive B-cells were decreased whereas Activated Memory (AM, Tissue-like Memory (TLM B-cells and Plasma cells were increased in both PHI and CHI patients. After 4 weeks of cART total B-cells increased, while AM, TLM B-cells and Plasma cells decreased, although without reaching normal levels in either group of individuals. This trend was maintained until week 48, though only total B-cells normalized in both PHI and CHI. Resting Memory (RM B-cells were preserved since baseline. This subset remained stable in CHI, while was expanded by an early initiation of cART during PHI. Untreated CHI patients showed IgM-overexpression at the expenses of switched (IgM-IgD- phenotypes of the memory subsets. Interestingly, in PHI patients a significant alteration of Immunoglobulin-expression was evident at BL in TLM cells, and after 4 weeks, despite treatment, in AM and RM subsets. After 48 weeks of therapy, Immunoglobulin-expression of AM and RM almost normalized, but remained perturbed in TLM cells in both groups.In conclusion, aberrant activated and exhausted B-cell phenotypes rose already during PHI, while most of the alterations in Ig-expression seen in CHI appeared later, despite 4 weeks of effective cART. After 48 weeks of cART B-cell subsets distribution improved although without full normalization, while Immunoglobulin-expression normalized

  12. Beneficial Effects of cART Initiated during Primary and Chronic HIV-1 Infection on Immunoglobulin-Expression of Memory B-Cell Subsets.

    Science.gov (United States)

    Pogliaghi, Manuela; Ripa, Marco; Pensieroso, Simone; Tolazzi, Monica; Chiappetta, Stefania; Nozza, Silvia; Lazzarin, Adriano; Tambussi, Giuseppe; Scarlatti, Gabriella

    2015-01-01

    During HIV-1 infection the B-cell compartment undergoes profound changes towards terminal differentiation, which are only partially restored by antiretroviral therapy (cART). To investigate the impact of infection as early as during primary HIV-1 infection (PHI) we assessed distribution of B-cell subsets in 19 PHI and 25 chronic HIV-1-infected (CHI) individuals before and during 48 weeks of cART as compared to healthy controls (n = 23). We also analysed Immunoglobulin-expression of memory B-cell subsets to identify alterations in Immunoglobulin-maturation. Determination of B-cell subsets at baseline showed that total and Naive B-cells were decreased whereas Activated Memory (AM), Tissue-like Memory (TLM) B-cells and Plasma cells were increased in both PHI and CHI patients. After 4 weeks of cART total B-cells increased, while AM, TLM B-cells and Plasma cells decreased, although without reaching normal levels in either group of individuals. This trend was maintained until week 48, though only total B-cells normalized in both PHI and CHI. Resting Memory (RM) B-cells were preserved since baseline. This subset remained stable in CHI, while was expanded by an early initiation of cART during PHI. Untreated CHI patients showed IgM-overexpression at the expenses of switched (IgM-IgD-) phenotypes of the memory subsets. Interestingly, in PHI patients a significant alteration of Immunoglobulin-expression was evident at BL in TLM cells, and after 4 weeks, despite treatment, in AM and RM subsets. After 48 weeks of therapy, Immunoglobulin-expression of AM and RM almost normalized, but remained perturbed in TLM cells in both groups. In conclusion, aberrant activated and exhausted B-cell phenotypes rose already during PHI, while most of the alterations in Ig-expression seen in CHI appeared later, despite 4 weeks of effective cART. After 48 weeks of cART B-cell subsets distribution improved although without full normalization, while Immunoglobulin-expression normalized among AM and

  13. Forearm Compartment Syndrome Caused by Reperfusion Injury

    Directory of Open Access Journals (Sweden)

    Ufuk Sayar

    2014-01-01

    Full Text Available Compartment syndrome is commonly seen following lower extremity ischemia. However, upper extremities’ compartment syndrome, especially after any vascular surgical procedures, is infrequent. Herein we report a case of an acute forearm compartment syndrome that was developed after delayed brachial artery embolectomy.

  14. Acute compartment syndrome after medial gastrocnemius tear.

    Science.gov (United States)

    Sit, Yan Kit; Lui, Tun Hing

    2015-02-01

    Acute compartment syndrome after medial gastrocnemius tear is very rare. It can involve the superficial posterior compartment alone or progress to involve all the 4 compartments of the lower legs. Those patients with high pain tolerance and minor trauma can lead to delayed presentation. Immediate fasciotomy is the treatment of choice. Therapeutic Level IV, Case Study. © 2014 The Author(s).

  15. 14 CFR 25.787 - Stowage compartments.

    Science.gov (United States)

    2010-01-01

    ... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Personnel and Cargo Accommodations § 25.787 Stowage compartments. (a) Each compartment for the stowage of cargo, baggage, carry-on articles, and... to compartments located below, or forward, of all occupants in the airplane. If the airplane has a...

  16. B-Cell waste classification sampling and analysis plan

    International Nuclear Information System (INIS)

    HOBART, R.L.

    1999-01-01

    This report documents the methods used to collect and analyze samples to obtain data necessary to verify and/or determine the radionuclide content of the 324 Facility B-Cell decontamination and decommissioning waste stream

  17. IL-21: an executor of B cell fate.

    Science.gov (United States)

    Konforte, Danijela; Simard, Nathalie; Paige, Christopher J

    2009-02-15

    IL-21 is a type I cytokine that shares the common receptor gamma-chain with IL-2, IL-4, IL-7, IL-9, and IL-15. B cells are one of the lymphoid cell types whose development and function are regulated by IL-21. Depending on the interplay with costimulatory signals and on the developmental stage of a B cell, IL-21 can induce proliferation, differentiation into Ig-producing plasma cells, or apoptosis in both mice and humans. Alone and in combination with Th cell-derived cytokines IL-21 can regulate class switch recombination to IgG, IgA, or IgE isotypes, indicating its important role in shaping the effector function of B cells. This review highlights the role of IL-21 in B cell development, function, and disease and provides some perspectives on the future studies in this area.

  18. Lymphoma and the control of B cell growth and differentiation.

    Science.gov (United States)

    Rui, Lixin; Goodnow, Christopher C

    2006-05-01

    It is now widely accepted that lymphomagenesis is a multistep transformation process. A number of genetic changes and environmental and infectious factors contributing to the development and malignant progression of B-cell lymphoproliferative disorders are well documented. Reciprocal chromosomal translocations involving the immunoglobulin loci are a hallmark of most mature B cell lymphomas and lead to dysregulated expression of proto-oncogenes (c-myc) important for cell proliferation or genes involved in cell cycle progression (cyclin D1), differentiation block (bcl-6, PAX5) and cell survival (bcl-2, NF-kappaB). In addition, genetic alterations that inactivate tumor suppressor genes (p53, p16) have been frequently detected in some lymphoma tissues. Many of these genes are normally regulated by signals from the B cell antigen receptor. The high prevalence of bacterial and viral infection in lymphoma patients supports the hypothesis that infectious agents may play a contributory role in the development and evolution of B cell lymphoproliferative disorders by either directly inducing polyclonal B cell hyperactivation (EBV, HCV), or providing a chronic antigenic stimulus (EBV, HCV, HBV, H. pylori), or mimicking B cell antigen receptor signaling (EBV, HCV, HHV8), although whether these are causative factors or they are secondary to genetic changes in lymphomagenesis remains to be defined. Stimulatory signals from reactive T cells, local cytokines and growth factors can also contribute, to some extent, to the progression of transformation. Modulation of B cell antigen receptor signaling therefore emerges as a potentially powerful strategy for controlling the growth of certain B cell lymphomas.

  19. 'Big bang' of B-cell development revealed.

    Science.gov (United States)

    Murre, Cornelis

    2018-01-15

    Earlier studies have identified transcription factors that specify B-cell fate, but the underlying mechanisms remain to be revealed. Two new studies by Miyai and colleagues (pp. 112-126) and Li and colleagues (pp. 96-111) in this issue of Genes & Development provide new and unprecedented insights into the genetic and epigenetic mechanisms that establish B-cell identity. © 2018 Murre; Published by Cold Spring Harbor Laboratory Press.

  20. 324 Facility B-Cell quality process plan

    International Nuclear Information System (INIS)

    Carlson, J.L.

    1998-01-01

    This report documents the quality process plan for the restart of a hot cell in the B Plant, originally a bismuth phosphate processing facility, but later converted to a waste fractionation plant. B-Cell is currently being cleaned out and deactivated. TPA Milestone M-89-02 dictates that all mixed waste and equipment be removed from B-Cell by 5/31/1999. This report describes the major activities that remain for completion of the TPA milestone

  1. EVIDENCE THAT INTESTINAL IGA PLASMA-CELLS IN MU,CHI TRANSGENIC MICE ARE DERIVED FROM B-1 (LY-1 B) CELLS

    NARCIS (Netherlands)

    KROESE, FGM; AMMERLAAN, WAM; KANTOR, AB

    1993-01-01

    B6-Sp6 transgenic mice carry fully rearranged (BALB/c-derived. Igh-C(a) allotype) mu heavy chain and kappa light chain transgenes, specific for trinitrophenyl, on a C57BL background (Igh-C(b) allotype). FACS analyses show that the majority of B cells in peripheral lymphoid organs and bone marrow

  2. Myeloid-derived suppressor cells in murine AIDS inhibit B-cell responses in part via soluble mediators including reactive oxygen and nitrogen species, and TGF-β

    Energy Technology Data Exchange (ETDEWEB)

    Rastad, Jessica L. [Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756 (United States); Green, William R., E-mail: William.R.Green@dartmouth.edu [Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756 (United States); Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756 (United States)

    2016-12-15

    Monocytic myeloid-derived suppressor cells (M-MDSCs) were increased during LP-BM5 retroviral infection, and were capable of suppressing not only T-cell, but also B-cell responses. In addition to previously demonstrating iNOS- and VISTA-dependent M-MDSC mechanisms, in this paper, we detail how M-MDSCs utilized soluble mediators, including the reactive oxygen and nitrogen species superoxide, peroxynitrite, and nitric oxide, and TGF-β, to suppress B cells in a predominantly contact-independent manner. Suppression was independent of cysteine-depletion and hydrogen peroxide production. When two major mechanisms of suppression (iNOS and VISTA) were eliminated in double knockout mice, M-MDSCs from LP-BM5-infected mice were able to compensate using other, soluble mechanisms in order to maintain suppression of B cells. The IL-10 producing regulatory B-cell compartment was among the targets of M-MDSC-mediated suppression. -- Highlights: •LP-BM5-expanded M-MDSCs utilized soluble mediators nitric oxide, superoxide, peroxynitrite, and TGF-β to suppress B cells. •When two major mechanisms of suppression were eliminated through knockouts, M-MDSCs maintained suppression. •M-MDSCs from LP-BM5-infected mice decreased proliferation of IL-10 producing regulatory B cells.

  3. Myeloid-derived suppressor cells in murine AIDS inhibit B-cell responses in part via soluble mediators including reactive oxygen and nitrogen species, and TGF-β

    International Nuclear Information System (INIS)

    Rastad, Jessica L.; Green, William R.

    2016-01-01

    Monocytic myeloid-derived suppressor cells (M-MDSCs) were increased during LP-BM5 retroviral infection, and were capable of suppressing not only T-cell, but also B-cell responses. In addition to previously demonstrating iNOS- and VISTA-dependent M-MDSC mechanisms, in this paper, we detail how M-MDSCs utilized soluble mediators, including the reactive oxygen and nitrogen species superoxide, peroxynitrite, and nitric oxide, and TGF-β, to suppress B cells in a predominantly contact-independent manner. Suppression was independent of cysteine-depletion and hydrogen peroxide production. When two major mechanisms of suppression (iNOS and VISTA) were eliminated in double knockout mice, M-MDSCs from LP-BM5-infected mice were able to compensate using other, soluble mechanisms in order to maintain suppression of B cells. The IL-10 producing regulatory B-cell compartment was among the targets of M-MDSC-mediated suppression. -- Highlights: •LP-BM5-expanded M-MDSCs utilized soluble mediators nitric oxide, superoxide, peroxynitrite, and TGF-β to suppress B cells. •When two major mechanisms of suppression were eliminated through knockouts, M-MDSCs maintained suppression. •M-MDSCs from LP-BM5-infected mice decreased proliferation of IL-10 producing regulatory B cells.

  4. Origin of B-Cell Neoplasms in Autoimmune Disease.

    Directory of Open Access Journals (Sweden)

    Kari Hemminki

    Full Text Available Autoimmune diseases (ADs are associated with a number of B-cell neoplasms but the associations are selective in regard to the type of neoplasm and the conferred risks are variable. So far no mechanistic bases for these differential associations have been demonstrated. We speculate that developmental origin of B-cells might propose a mechanistic rationale for their carcinogenic response to autoimmune stimuli and tested the hypothesis on our previous studies on the risks of B-cell neoplasms after any of 33 ADs. We found that predominantly germinal center (GC-derived B-cells showed multiple associations with ADs: diffuse large B cell lymphoma associated with 15 ADs, follicular lymphoma with 7 ADs and Hodgkin lymphoma with 11 ADs. Notably, these neoplasms shared significant associations with 5 ADs (immune thrombocytopenic purpura, polymyositis/dermatomyositis, rheumatoid arthritis, Sjogren syndrome and systemic lupus erythematosis. By contrast, primarily non-GC neoplasms, acute lymphocytic leukemia, chronic lymphocytic leukemia and myeloma associated with 2 ADs only and mantle cell lymphoma with 1 AD. None of the neoplasms shared associated ADs. These data may suggest that autoimmune stimulation critically interferes with the rapid cell division, somatic hypermutation, class switch recombination and immunological selection of maturing B-cell in the GC and delivers damage contributing to transformation.

  5. Age-associated distribution of normal B-cell and plasma cell subsets in peripheral blood

    NARCIS (Netherlands)

    Blanco, E. (Elena); M. Perez-Andres; Arriba-Méndez, S. (Sonia); Contreras-Sanfeliciano, T. (Teresa); I. Criado (Ignacio); Pelak, O. (Ondrej); Serra-Caetano, A. (Ana); A. Romero (Alfonso); N. Puig (Noemí); Remesal, A. (Ana); Torres Canizales, J. (Juan); E. Lopez-Granados (Eduardo); T. Kalina (Tomas); Sousa, A.E. (Ana E.); M.C. van Zelm (Menno); M. van der Burg (Mirjam); J.J.M. van Dongen (Jacques); Orfao, A. (Alberto)

    2018-01-01

    textabstractBackground: Humoral immunocompetence develops stepwise throughout life and contributes to individual susceptibility to infection, immunodeficiency, autoimmunity, and neoplasia. Immunoglobulin heavy chain (IgH) isotype serum levels can partly explain such age-related differences, but

  6. The distribution of IL-13 receptor alpha1 expression on B cells, T cells and monocytes and its regulation by IL-13 and IL-4.

    Science.gov (United States)

    Graber, P; Gretener, D; Herren, S; Aubry, J P; Elson, G; Poudrier, J; Lecoanet-Henchoz, S; Alouani, S; Losberger, C; Bonnefoy, J Y; Kosco-Vilbois, M H; Gauchat, J F

    1998-12-01

    To study the expression of IL-13 receptor alpha1 (IL-13Ralpha1), specific monoclonal antibodies (mAb) were generated. Surface expression of the IL-13Ralpha1 on B cells, monocytes and T cells was assessed by flow cytometry using these specific mAb. Among tonsillar B cells, the expression was the highest on the IgD+ CD38- B cell subpopulation which is believed to represent naive B cells. Expression was also detectable on a large fraction of the IgD-CD38- B cells but not on CD38+ B cells. Activation under conditions which promote B cell Ig class switching up-regulated the expression of the receptor. However, the same stimuli had an opposite effect for IL-13Ralpha1 expression levels on monocytes. While IL-13Ralpha1 mRNA was clearly detectable in T cell preparations, no surface expression was detected. However, permeabilization of the T cells showed a clear intracellular expression of the receptor. A soluble form of the receptor was immunoprecipitated from the supernatant of activated peripheral T cells, suggesting that T cell IL-13Ralpha1 might have functions unrelated to the capacity to form a type II IL-4/IL-13R with IL-4Ralpha.

  7. Persistence and selection of an expanded B-cell clone in the setting of rituximab therapy for Sjögren’s syndrome

    Science.gov (United States)

    2014-01-01

    Introduction Subjects with primary Sjögren’s syndrome (SjS) have an increased risk of developing B-cell lymphoma and may harbor monoclonal B-cell expansions in the peripheral blood. Expanded B-cell clones could be pathogenic, and their persistence could exacerbate disease or predispose toward the development of lymphoma. Therapy with anti-CD20 (rituximab) has the potential to eliminate expanded B-cell clones and thereby potentially ameliorate disease. This study was undertaken to identify and track expanded B-cell clones in the blood of subjects with primary SjS who were treated with rituximab. Methods To determine whether circulating B-cell clones in subjects with primary SjS emerge or remain after B cell-depleting therapy with rituximab, we studied the antibody heavy-chain repertoire. We performed single-memory B-cell and plasmablast sorting and antibody heavy-chain sequencing in six rituximab-treated SjS subjects over the course of a 1-year follow-up period. Results Expanded B-cell clones were identified in four out of the six rituximab-treated SjS subjects, based upon the independent amplification of sequences with identical or highly similar VH, DH, and JH gene segments. We identified one SjS subject with a large expanded B-cell clone that was present prior to therapy and persisted after therapy. Somatic mutations in the clone were numerous but did not increase in frequency over the course of the 1-year follow-up, suggesting that the clone had been present for a long period of time. Intriguingly, a majority of the somatic mutations in the clone were silent, suggesting that the clone was under chronic negative selection. Conclusions For some subjects with primary SjS, these data show that (a) expanded B-cell clones are readily identified in the peripheral blood, (b) some clones are not eliminated by rituximab, and (c) persistent clones may be under chronic negative selection or may not be antigen-driven. The analysis of sequence variation among members of an

  8. Persistence and selection of an expanded B-cell clone in the setting of rituximab therapy for Sjögren's syndrome.

    Science.gov (United States)

    Hershberg, Uri; Meng, Wenzhao; Zhang, Bochao; Haff, Nancy; St Clair, E William; Cohen, Philip L; McNair, Patrice D; Li, Ling; Levesque, Marc C; Luning Prak, Eline T

    2014-02-11

    Subjects with primary Sjögren's syndrome (SjS) have an increased risk of developing B-cell lymphoma and may harbor monoclonal B-cell expansions in the peripheral blood. Expanded B-cell clones could be pathogenic, and their persistence could exacerbate disease or predispose toward the development of lymphoma. Therapy with anti-CD20 (rituximab) has the potential to eliminate expanded B-cell clones and thereby potentially ameliorate disease. This study was undertaken to identify and track expanded B-cell clones in the blood of subjects with primary SjS who were treated with rituximab. To determine whether circulating B-cell clones in subjects with primary SjS emerge or remain after B cell-depleting therapy with rituximab, we studied the antibody heavy-chain repertoire. We performed single-memory B-cell and plasmablast sorting and antibody heavy-chain sequencing in six rituximab-treated SjS subjects over the course of a 1-year follow-up period. Expanded B-cell clones were identified in four out of the six rituximab-treated SjS subjects, based upon the independent amplification of sequences with identical or highly similar VH, DH, and JH gene segments. We identified one SjS subject with a large expanded B-cell clone that was present prior to therapy and persisted after therapy. Somatic mutations in the clone were numerous but did not increase in frequency over the course of the 1-year follow-up, suggesting that the clone had been present for a long period of time. Intriguingly, a majority of the somatic mutations in the clone were silent, suggesting that the clone was under chronic negative selection. For some subjects with primary SjS, these data show that (a) expanded B-cell clones are readily identified in the peripheral blood, (b) some clones are not eliminated by rituximab, and (c) persistent clones may be under chronic negative selection or may not be antigen-driven. The analysis of sequence variation among members of an expanded clone may provide a novel means

  9. Human regulatory B cells control the TFH cell response.

    Science.gov (United States)

    Achour, Achouak; Simon, Quentin; Mohr, Audrey; Séité, Jean-François; Youinou, Pierre; Bendaoud, Boutahar; Ghedira, Ibtissem; Pers, Jacques-Olivier; Jamin, Christophe

    2017-07-01

    Follicular helper T (T FH ) cells support terminal B-cell differentiation. Human regulatory B (Breg) cells modulate cellular responses, but their control of T FH cell-dependent humoral immune responses is unknown. We sought to assess the role of Breg cells on T FH cell development and function. Human T cells were polyclonally stimulated in the presence of IL-12 and IL-21 to generate T FH cells. They were cocultured with B cells to induce their terminal differentiation. Breg cells were included in these cultures, and their effects were evaluated by using flow cytometry and ELISA. B-cell lymphoma 6, IL-21, inducible costimulator, CXCR5, and programmed cell death protein 1 (PD-1) expressions increased on stimulated human T cells, characterizing T FH cell maturation. In cocultures they differentiated B cells into CD138 + plasma and IgD - CD27 + memory cells and triggered immunoglobulin secretions. Breg cells obtained by Toll-like receptor 9 and CD40 activation of B cells prevented T FH cell development. Added to T FH cell and B-cell cocultures, they inhibited B-cell differentiation, impeded immunoglobulin secretions, and expanded Foxp3 + CXCR5 + PD-1 + follicular regulatory T cells. Breg cells modulated IL-21 receptor expressions on T FH cells and B cells, and their suppressive activities involved CD40, CD80, CD86, and intercellular adhesion molecule interactions and required production of IL-10 and TGF-β. Human Breg cells control T FH cell maturation, expand follicular regulatory T cells, and inhibit the T FH cell-mediated antibody secretion. These novel observations demonstrate a role for the Breg cell in germinal center reactions and suggest that deficient activities might impair the T FH cell-dependent control of humoral immunity and might lead to the development of aberrant autoimmune responses. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  10. Bruton tyrosine kinase inhibitor ibrutinib (PCI-32765) has significant activity in patients with relapsed/refractory B-cell malignancies.

    Science.gov (United States)

    Advani, Ranjana H; Buggy, Joseph J; Sharman, Jeff P; Smith, Sonali M; Boyd, Thomas E; Grant, Barbara; Kolibaba, Kathryn S; Furman, Richard R; Rodriguez, Sara; Chang, Betty Y; Sukbuntherng, Juthamas; Izumi, Raquel; Hamdy, Ahmed; Hedrick, Eric; Fowler, Nathan H

    2013-01-01

    Survival and progression of mature B-cell malignancies depend on signals from the B-cell antigen receptor, and Bruton tyrosine kinase (BTK) is a critical signaling kinase in this pathway. We evaluated ibrutinib (PCI-32765), a small-molecule irreversible inhibitor of BTK, in patients with B-cell malignancies. Patients with relapsed or refractory B-cell lymphoma and chronic lymphocytic leukemia received escalating oral doses of ibrutinib. Two schedules were evaluated: one, 28 days on, 7 days off; and two, once-daily continuous dosing. Occupancy of BTK by ibrutinib in peripheral blood was monitored using a fluorescent affinity probe. Dose escalation proceeded until either the maximum-tolerated dose (MTD) was achieved or, in the absence of MTD, until three dose levels above full BTK occupancy by ibrutinib. Response was evaluated every two cycles. Fifty-six patients with a variety of B-cell malignancies were treated over seven cohorts. Most adverse events were grade 1 and 2 in severity and self-limited. Dose-limiting events were not observed, even with prolonged dosing. Full occupancy of the BTK active site occurred at 2.5 mg/kg per day, and dose escalation continued to 12.5 mg/kg per day without reaching MTD. Pharmacokinetic data indicated rapid absorption and elimination, yet BTK occupancy was maintained for at least 24 hours, consistent with the irreversible mechanism. Objective response rate in 50 evaluable patients was 60%, including complete response of 16%. Median progression-free survival in all patients was 13.6 months. Ibrutinib, a novel BTK-targeting inhibitor, is well tolerated, with substantial activity across B-cell histologies.

  11. TIM-1 signaling in B cells regulates antibody production

    International Nuclear Information System (INIS)

    Ma, Juan; Usui, Yoshihiko; Takeda, Kazuyoshi; Harada, Norihiro; Yagita, Hideo; Okumura, Ko; Akiba, Hisaya

    2011-01-01

    Highlights: → TIM-1 is highly expressed on anti-IgM + anti-CD40-stimulated B cells. → Anti-TIM-1 mAb enhanced proliferation and Ig production on activated B cell in vitro. → TIM-1 signaling regulates Ab production by response to TI-2 and TD antigens in vivo. -- Abstract: Members of the T cell Ig and mucin (TIM) family have recently been implicated in the control of T cell-mediated immune responses. In this study, we found TIM-1 expression on anti-IgM- or anti-CD40-stimulated splenic B cells, which was further up-regulated by the combination of anti-IgM and anti-CD40 Abs. On the other hand, TIM-1 ligand was constitutively expressed on B cells and inducible on anti-CD3 + anti-CD28-stimulated CD4 + T cells. In vitro stimulation of activated B cells by anti-TIM-1 mAb enhanced proliferation and expression of a plasma cell marker syndecan-1 (CD138). We further examined the effect of TIM-1 signaling on antibody production in vitro and in vivo. Higher levels of IgG2b and IgG3 secretion were detected in the culture supernatants of the anti-TIM-1-stimulated B cells as compared with the control IgG-stimulated B cells. When immunized with T-independent antigen TNP-Ficoll, TNP-specific IgG1, IgG2b, and IgG3 Abs were slightly increased in the anti-TIM-1-treated mice. When immunized with T-dependent antigen OVA, serum levels of OVA-specific IgG2b, IgG3, and IgE Abs were significantly increased in the anti-TIM-1-treated mice as compared with the control IgG-treated mice. These results suggest that TIM-1 signaling in B cells augments antibody production by enhancing B cell proliferation and differentiation.

  12. TIM-1 signaling in B cells regulates antibody production

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Juan [Department of Immunology, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Usui, Yoshihiko [Department of Immunology, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Department of Ophthalmology, Tokyo Medical University, 6-7-1 Nishi-shinjuku-ku, Tokyo 160-0023 (Japan); Takeda, Kazuyoshi [Department of Immunology, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Harada, Norihiro [Department of Immunology, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Department of Respiratory Medicine, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Research Institute for Diseases of Old Ages, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Yagita, Hideo; Okumura, Ko [Department of Immunology, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Akiba, Hisaya, E-mail: hisaya@juntendo.ac.jp [Department of Immunology, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan)

    2011-03-11

    Highlights: {yields} TIM-1 is highly expressed on anti-IgM + anti-CD40-stimulated B cells. {yields} Anti-TIM-1 mAb enhanced proliferation and Ig production on activated B cell in vitro. {yields} TIM-1 signaling regulates Ab production by response to TI-2 and TD antigens in vivo. -- Abstract: Members of the T cell Ig and mucin (TIM) family have recently been implicated in the control of T cell-mediated immune responses. In this study, we found TIM-1 expression on anti-IgM- or anti-CD40-stimulated splenic B cells, which was further up-regulated by the combination of anti-IgM and anti-CD40 Abs. On the other hand, TIM-1 ligand was constitutively expressed on B cells and inducible on anti-CD3{sup +} anti-CD28-stimulated CD4{sup +} T cells. In vitro stimulation of activated B cells by anti-TIM-1 mAb enhanced proliferation and expression of a plasma cell marker syndecan-1 (CD138). We further examined the effect of TIM-1 signaling on antibody production in vitro and in vivo. Higher levels of IgG2b and IgG3 secretion were detected in the culture supernatants of the anti-TIM-1-stimulated B cells as compared with the control IgG-stimulated B cells. When immunized with T-independent antigen TNP-Ficoll, TNP-specific IgG1, IgG2b, and IgG3 Abs were slightly increased in the anti-TIM-1-treated mice. When immunized with T-dependent antigen OVA, serum levels of OVA-specific IgG2b, IgG3, and IgE Abs were significantly increased in the anti-TIM-1-treated mice as compared with the control IgG-treated mice. These results suggest that TIM-1 signaling in B cells augments antibody production by enhancing B cell proliferation and differentiation.

  13. Apoptosis-Inducing-Factor-Dependent Mitochondrial Function Is Required for T Cell but Not B Cell Function.

    Science.gov (United States)

    Milasta, Sandra; Dillon, Christopher P; Sturm, Oliver E; Verbist, Katherine C; Brewer, Taylor L; Quarato, Giovanni; Brown, Scott A; Frase, Sharon; Janke, Laura J; Perry, S Scott; Thomas, Paul G; Green, Douglas R

    2016-01-19

    The role of apoptosis inducing factor (AIF) in promoting cell death versus survival remains controversial. We report that the loss of AIF in fibroblasts led to mitochondrial electron transport chain defects and loss of proliferation that could be restored by ectopic expression of the yeast NADH dehydrogenase Ndi1. Aif-deficiency in T cells led to decreased peripheral T cell numbers and defective homeostatic proliferation, but thymic T cell development was unaffected. In contrast, Aif-deficient B cells developed and functioned normally. The difference in the dependency of T cells versus B cells on AIF for function and survival correlated with their metabolic requirements. Ectopic Ndi1 expression rescued homeostatic proliferation of Aif-deficient T cells. Despite its reported roles in cell death, fibroblasts, thymocytes and B cells lacking AIF underwent normal death. These studies suggest that the primary role of AIF relates to complex I function, with differential effects on T and B cells. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Microenvironment-Centred Dynamics in Aggressive B-Cell Lymphomas

    Directory of Open Access Journals (Sweden)

    Matilde Cacciatore

    2012-01-01

    Full Text Available Aggressive B-cell lymphomas share high proliferative and invasive attitudes and dismal prognosis despite heterogeneous biological features. In the interchained sequence of events leading to cancer progression, neoplastic clone-intrinsic molecular events play a major role. Nevertheless, microenvironment-related cues have progressively come into focus as true determinants for this process. The cancer-associated microenvironment is a complex network of nonneoplastic immune and stromal cells embedded in extracellular components, giving rise to a multifarious crosstalk with neoplastic cells towards the induction of a supportive milieu. The immunological and stromal microenvironments have been classically regarded as essential partners of indolent lymphomas, while considered mainly negligible in the setting of aggressive B-cell lymphomas that, by their nature, are less reliant on external stimuli. By this paper we try to delineate the cardinal microenvironment-centred dynamics exerting an influence over lymphoid clone progression in aggressive B-cell lymphomas.

  15. The acquisition of cytokine responsiveness by murine B cells

    DEFF Research Database (Denmark)

    Poudrier, J; Owens, T

    1994-01-01

    chains and mRNA to levels comparable to those seen in activated T cells. Anti-mu-stimulated B cells responded to IL-2 by incorporation of [3H]thymidine and high rate immunoglobulin (Ig) secretion. Both IL-5 (at optimal concentration) and suboptimal lipopolysaccharide (LPS; 20 ng/ml) induced surface...... expression of IL-2R alpha. The level of expression induced by IL-5 was equivalent to that on anti-Ig-activated B cells. Neither stimulus induced detectable expression of IL-2R beta, and neither induced B cells to respond to IL-2. IL-2R alpha expression was strongly enhanced, and low levels of IL-2R beta...

  16. 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...

  17. Dataset of transcriptional landscape of B cell early activation

    Directory of Open Access Journals (Sweden)

    Alexander S. Garruss

    2015-09-01

    Full Text Available Signaling via B cell receptors (BCR and Toll-like receptors (TLRs result in activation of B cells with distinct physiological outcomes, but transcriptional regulatory mechanisms that drive activation and distinguish these pathways remain unknown. At early time points after BCR and TLR ligand exposure, 0.5 and 2 h, RNA-seq was performed allowing observations on rapid transcriptional changes. At 2 h, ChIP-seq was performed to allow observations on important regulatory mechanisms potentially driving transcriptional change. The dataset includes RNA-seq, ChIP-seq of control (Input, RNA Pol II, H3K4me3, H3K27me3, and a separate RNA-seq for miRNA expression, which can be found at Gene Expression Omnibus Dataset GSE61608. Here, we provide details on the experimental and analysis methods used to obtain and analyze this dataset and to examine the transcriptional landscape of B cell early activation.

  18. Effect of antigen on localization of immunologically specific B cells

    International Nuclear Information System (INIS)

    Ponzio, N.M.; Chapman, J.M.; Thorbecke, G.J.

    1976-01-01

    Studies were conducted to demonstrate homing of memory B cells to sites of antigen localization in lymph nodes, using functional criteria to detect local presence of memory cells at varying intervals after intravenous injection. Cell suspensions were prepared from spleens of donor mice injected with complete Freund's adjuvant. Recipient mice were injected with Escherichia coli endotoxin and immune or normal spleen cells and were gamma-irradiated. Results indicated that passively transferred unilateral B cell memory was established. The development over a period of several days of this difference between left and right lymph nodes suggests that recirculating memory B cells are being progressively selected by antigen in the lymph node, rather than that this difference is due to a specific exit of cells from the circulation towards the antigen

  19. A rare cause of ischemic stroke: Intravasculer B cell lymphoma

    Directory of Open Access Journals (Sweden)

    Şeyma Çiftçi

    2014-08-01

    Full Text Available Intravascular B cell lymphoma is rare and an agressive form of large B cell lymphoma which can affect central nervous system. Because of its varied clinical symptoms and the absence of lymphadenopathy, it is generally diagnosed postmortem. Cerebral infarction due to occlusion of arteries can be seen as a rare clinical form of central nervous system involvement. Large artery atherosclerosis, cardiyoembolism and small artery occlusion are the important causes of ischemic stroke but no any cause is detected in %15-40 of all cases. In this report, with the discussion of a case with ischemia like encephalopathy and multiple cerebral ischemic lesions at different stages in cranial MRI which was diagnosed by the help of brain biopsy as a intravascular B cell lymphoma, it is aimed to take attention intravascular lymphoma as a rare cause of ischemic stroke.

  20. Acute compartment syndrome caused by uncontrolled hypothyroidism.

    Science.gov (United States)

    Modi, Anar; Amin, Hari; Salzman, Matthew; Morgan, Farah

    2017-06-01

    Acute compartment syndrome is increased tissue pressure exceeding perfusion pressure in a closed compartment resulting in nerve and muscle ischemia. Common precipitating causes are crush injuries, burns, substance abuse, osseous or vascular limb trauma. This is a case of 42year old female with history of hypothyroidism who presented to emergency room with acute onset of severe pain and swelling in right lower extremity. Physical examination was concerning for acute compartment syndrome of right leg which was confirmed by demonstration of elevated compartmental pressures. No precipitating causes were readily identified. Further laboratory testing revealed uncontrolled hypothyroidism. Management included emergent fasciotomy and initiating thyroid hormone replacement. This case represents a rare association between acute compartment syndrome and uncontrolled hypothyroidism. We also discuss the pathogenesis of compartment syndrome in hypothyroid patients and emphasize the importance of evaluating for less common causes, particularly in setting of non-traumatic compartment syndrome. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. IgM and IgD B cell receptors differentially respond to endogenous antigens and control B cell fate

    Science.gov (United States)

    Noviski, Mark; Mueller, James L; Satterthwaite, Anne; Garrett-Sinha, Lee Ann; Brombacher, Frank

    2018-01-01

    Naive B cells co-express two BCR isotypes, IgM and IgD, with identical antigen-binding domains but distinct constant regions. IgM but not IgD is downregulated on autoreactive B cells. Because these isotypes are presumed to be redundant, it is unknown how this could impose tolerance. We introduced the Nur77-eGFP reporter of BCR signaling into mice that express each BCR isotype alone. Despite signaling strongly in vitro, IgD is less sensitive than IgM to endogenous antigen in vivo and developmental fate decisions are skewed accordingly. IgD-only Lyn−/− B cells cannot generate autoantibodies and short-lived plasma cells (SLPCs) in vivo, a fate thought to be driven by intense BCR signaling induced by endogenous antigens. Similarly, IgD-only B cells generate normal germinal center, but impaired IgG1+ SLPC responses to T-dependent immunization. We propose a role for IgD in maintaining the quiescence of autoreactive B cells and restricting their differentiation into autoantibody secreting cells. PMID:29521626

  2. Understanding B-cell activation and autoantibody repertoire selection in systemic lupus erythematosus: A B-cell immunomics approach.

    Science.gov (United States)

    Tipton, Christopher M; Hom, Jennifer R; Fucile, Christopher F; Rosenberg, Alexander F; Sanz, Inaki

    2018-07-01

    Understanding antibody repertoires and in particular, the properties and fates of B cells expressing potentially pathogenic antibodies is critical to define the mechanisms underlying multiple immunological diseases including autoimmune and allergic conditions as well as transplant rejection. Moreover, an integrated knowledge of the antibody repertoires expressed by B cells and plasma cells (PC) of different functional properties and longevity is essential to develop new therapeutic strategies, better biomarkers for disease segmentation, and new assays to measure restoration of B-cell tolerance or, at least, of normal B-cell homeostasis. Reaching these goals, however, will require a more precise phenotypic, functional and molecular definition of B-cell and PC populations, and a comprehensive analysis of the antigenic reactivity of the antibodies they express. While traditionally hampered by technical and ethical limitations in human experimentation, new technological advances currently enable investigators to address these questions in a comprehensive fashion. In this review, we shall discuss these concepts as they apply to the study of Systemic Lupus Erythematosus. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Reprogramming of B cells into macrophages: mechanistic insights

    OpenAIRE

    Di Tullio, Alessandro, 1982-

    2012-01-01

    Our earlier work has shown that pre-B cells can be converted into macrophages by the transcription factor C/EBPα at very high frequencies and also that a clonal pre-B cell line with an inducible form of C/EBPα can be converted into macrophage-like cells. Using these systems we have performed a systematic analysis of the questions whether during transdifferentiation the cells retrodifferentiate to a precursor cell state and whether cell cycle is required for reprogramming. As for the first ...

  4. Immunomodulating effects of heparin on human B cell proliferation

    International Nuclear Information System (INIS)

    Wasik, Maria; Stepien-Sopniewska, Barbara; Gorski, Andrzej

    1993-01-01

    Recent data indicate that heparin may act as an immunomodulator. In this paper we have analyzed the effect of this agent on human B cell proliferation ''in vitro'' induced by ''S. aureus'' Cowan. The action of heparin is complex, but there was a trend for inhibition of B cell responses obtained from defibrinated but not heparinized blood samples. This suggest that heparin interacts with platelet products (growth factors, cytokines) and the results of such interactions determine the final effect. (author). 6 refs, 4 figs

  5. Forearm Compartment Syndrome: Evaluation and Management.

    Science.gov (United States)

    Kistler, Justin M; Ilyas, Asif M; Thoder, Joseph J

    2018-02-01

    Compartment syndrome of the forearm is uncommon but can have devastating consequences. Compartment syndrome is a result of osseofascial swelling leading to decreased tissue perfusion and tissue necrosis. There are numerous causes of forearm compartment syndrome and high clinical suspicion must be maintained to avoid permanent disability. The most widely recognized symptoms include pain out of proportion and pain with passive stretch of the wrist and digits. Early diagnosis and decompressive fasciotomy are essential in the treatment of forearm compartment syndrome. Closure of fasciotomy wounds can often be accomplished by primary closure but many patients require additional forms of soft tissue coverage procedures. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Flow cytometric analysis of immunoglobulin heavy chain expression in B-cell lymphoma and reactive lymphoid hyperplasia

    Science.gov (United States)

    Grier, David D; Al-Quran, Samer Z; Cardona, Diana M; Li, Ying; Braylan, Raul C

    2012-01-01

    The diagnosis of B-cell lymphoma (BCL) is often dependent on the detection of clonal immunoglobulin (Ig) light chain expression. In some BCLs, the determination of clonality based on Ig light chain restriction may be difficult. The aim of our study was to assess the utility of flow cytometric analysis of surface Ig heavy chain (HC) expression in lymphoid tissues in distinguishing lymphoid hyperplasias from BCLs, and also differentiating various BCL subtypes. HC expression on B-cells varied among different types of hyperplasias. In follicular hyperplasia, IgM and IgD expression was high in mantle cells while germinal center cells showed poor HC expression. In other hyperplasias, B cell compartments were blurred but generally showed high IgD and IgM expression. Compared to hyperplasias, BCLs varied in IgM expression. Small lymphocytic lymphomas had lower IgM expression than mantle cell lymphomas. Of importance, IgD expression was significantly lower in BCLs than in hyperplasias, a finding that can be useful in differentiating lymphoma from reactive processes. PMID:22400070

  7. Next generation sequencing reveals skewing of the T and B cell receptor repertoires in patients with Wiskott Aldrich syndrome

    Directory of Open Access Journals (Sweden)

    Amy E O'Connell

    2014-07-01

    Full Text Available The Wiskott Aldrich syndrome (WAS is due to mutations of the WAS gene encoding for the cytoskeletal WAS protein (WASp, leading to abnormal downstream signaling from the T cell and B cell antigen receptors (TCR, BCR. We hypothesized that the impaired signaling through the TCR and BCR in WAS would subsequently lead to aberrations in the immune repertoire of WAS patients. Using next generation sequencing, the T cell receptor beta (TRB and B cell immunoglobulin heavy chain (IGH repertoires of 8 patients with WAS and 6 controls were sequenced. Clonal expansions were identified within memory CD4+ cells, as well as in total, naïve and memory CD8+ cells from WAS patients. In the B cell compartment, WAS patient IGH repertoires were also clonally expanded and showed skewed usage of IGHV and IGHJ genes, and increased usage of IGHG constant genes, compared with controls. To our knowledge, this is the first study that demonstrates significant abnormalities of the immune repertoire in WAS patients using next generation sequencing.

  8. Efficacy of Intravenous Cyclophosphamide Pulse Therapy for P-Glycoprotein-expressing B Cell-associated Active True Renal Lupus Vasculitis in Lupus Nephritis

    Science.gov (United States)

    Kawabe, Akio; Tsujimura, Shizuyo; Saito, Kazuyoshi; Tanaka, Yoshiya

    2017-01-01

    True renal lupus vasculitis (TRLV), a vascular lesion usually associated with proliferative lupus nephritis (LN), is resistant to conventional treatments. The expression of P-glycoprotein (P-gp) on activated lymphocytes causes drug resistance. We herein report a patient with TRLV, minimal change LN, overexpression of P-gp on peripheral B cells, and accumulation of P-gp+ B cells at the site of TRLV. High-dose corticosteroids combined with intravenous cyclophosphamide pulse therapy resulted in clinical remission and the long-term normal renal function. PMID:28626187

  9. Anti-HIV-1 B cell responses are dependent on B cell precursor frequency and antigen-binding affinity.

    Science.gov (United States)

    Dosenovic, Pia; Kara, Ervin E; Pettersson, Anna-Klara; McGuire, Andrew T; Gray, Matthew; Hartweger, Harald; Thientosapol, Eddy S; Stamatatos, Leonidas; Nussenzweig, Michel C

    2018-04-16

    The discovery that humans can produce potent broadly neutralizing antibodies (bNAbs) to several different epitopes on the HIV-1 spike has reinvigorated efforts to develop an antibody-based HIV-1 vaccine. Antibody cloning from single cells revealed that nearly all bNAbs show unusual features that could help explain why it has not been possible to elicit them by traditional vaccination and instead would require a sequence of different immunogens. This idea is supported by experiments with genetically modified immunoglobulin (Ig) knock-in mice. Sequential immunization with a series of specifically designed immunogens was required to shepherd the development of bNAbs. However, knock-in mice contain superphysiologic numbers of bNAb precursor-expressing B cells, and therefore how these results can be translated to a more physiologic setting remains to be determined. Here we make use of adoptive transfer experiments using knock-in B cells that carry a synthetic intermediate in the pathway to anti-HIV-1 bNAb development to examine how the relationship between B cell receptor affinity and precursor frequency affects germinal center (GC) B cell recruitment and clonal expansion. Immunization with soluble HIV-1 antigens can recruit bNAb precursor B cells to the GC when there are as few as 10 such cells per mouse. However, at low precursor frequencies, the extent of clonal expansion is directly proportional to the affinity of the antigen for the B cell receptor, and recruitment to GCs is variable and dependent on recirculation.

  10. 324 Facility B-Cell quality process plan

    International Nuclear Information System (INIS)

    Carlson, J.L.

    1998-01-01

    B-Cell is currently being cleaned out (i.e., removal of equipment, fixtures and residual radioactive materials) and deactivated. TPA Milestone M-89-02 dictates that all mixed waste and equipment be removed from B-Cell by 5/31/99. The following sections describe the major activities that remain for completion of the TPA milestone. This includes: (1) Size Reduce Tank 119 and Miscellaneous Equipment. This activity is the restart of hotwork in B-Cell to size reduce the remainder of Tank 119 and other miscellaneous pieces of equipment into sizes that can be loaded into a grout container. This activity also includes the process of preparing the containers for shipment from the cell. The specific activities and procedures used are detailed in a table. (2) Load and Ship Low-Level Waste. This activity covers the process of taking a grouted LLW container from B-Cell and loading it into the cask in the REC airlock and Cask Handling Area (CHA) for shipment to the LLBG. The detailed activities and procedures for this part of cell cleanout are included in second table

  11. Targeting the BCR signalosome in B cell malignancies

    NARCIS (Netherlands)

    de Rooij, M.F.M.

    2017-01-01

    Chronic lymphocytic leukemia (CLL), mantle cell lymphoma (MCL), and Waldenström macroglobulinemia (WM) are B-cell malignancies which are still incurable. In these lymphomas, the cells proliferate in specialized niches in lymph nodes and bone marrow, in which they are provided by stromal-derived

  12. [Ibrutinib: A new drug of B-cell malignancies].

    Science.gov (United States)

    Thieblemont, Catherine

    2015-06-01

    Ibrutinib (Imbruvica®) is a first-in-class, orally administered once-daily, that inhibits B-cell antigen receptor signaling downstream of Bruton's tyrosine kinase (BTK). Ibrutinib has been approved in USA in February 2014 and in France in October 2014 for the treatment of patients with relapsed/refractory mantle cell lymphoma (MCL) or chronic lymphocytic leukaemia (CLL) and for the treatment of patients with CLL and a chromosome 17 deletion (del 17p) or TP53 mutation. In clinical studies, ibrutinib induced an impressive overall response rate (68%) in patients with relapsed/refractory MCL (phase II study). In CLL, ibrutinib has shown to significantly improve progression-free survival, response rate and overall survival in patients with relapsed/refractory CLL, including in those with del 17p. Ibrutinib had an acceptable tolerability profile. Less than 10% of patients discontinued their treatment because of adverse events. Results are pending in other B-cell lymphomas subtypes such as in diffuse large B-cell lymphoma and in follicular lymphoma. An approval extension has already been enregistered for Waldenström disease in USA in January 2015. Given its efficacy and tolerability, ibrutinib is an emerging treatment option for patients with B-cell malignancies. Copyright © 2015 Société Françise du Cancer. Publié par Elsevier Masson SAS. Tous droits réservés. Published by Elsevier Masson SAS. All rights reserved.

  13. Role of Bruton's tyrosine kinase in B cells and malignancies

    NARCIS (Netherlands)

    Pal Singh, S. (Simar); F. Dammeijer (Floris); R.W. Hendriks (Rudi)

    2018-01-01

    textabstractBruton's tyrosine kinase (BTK) is a non-receptor kinase that plays a crucial role in oncogenic signaling that is critical for proliferation and survival of leukemic cells in many B cell malignancies. BTK was initially shown to be defective in the primary immunodeficiency X-linked

  14. Immunomodulatory effect of Mesenchymal Stem Cells on B cells

    Directory of Open Access Journals (Sweden)

    Marcella eFranquesa

    2012-07-01

    Full Text Available The research on T cell immunosuppression therapies has attracted most of the attention in clinical transplantation. However, B cells and humoral immune responses are increasingly acknowledged as crucial mediators of chronic allograft rejection. Indeed, humoral immune responses can lead to renal allograft rejection even in patients whose cell-mediated immune responses are well controlled. On the other hand, newly studied B cell subsets with regulatory effects have been linked to tolerance achievement in transplantation. Better understanding of the regulatory and effector B cell responses may therefore lead to new therapeutic approaches.Mesenchymal Stem Cells (MSC are arising as a potent therapeutic tool in transplantation due to their regenerative and immunomodulatory properties. The research on MSCs has mainly focused on their effects on T cells and although data regarding the modulatory effects of MSCs on alloantigen-specific humoral response in humans is scarce, it has been demonstrated that MSCs significantly affect B cell functioning. In the present review we will analyze and discuss the results in this field.

  15. Profiling of diffuse large B-cell lymphoma by immunohistochemistry

    DEFF Research Database (Denmark)

    Sjö, Lene Dissing; Poulsen, Christian Bjørn; Hansen, Mads

    2007-01-01

    Diffuse large B-cell lymphoma (DLBCL) is a frequent lymphoma subtype with a heterogeneous behavior and a variable response to conventional chemotherapy. This clinical diversity is believed to reflect differences in the molecular pathways leading to lymphomagenesis. In this study, we have analyzed...

  16. Likelihood-Based Inference of B Cell Clonal Families.

    Directory of Open Access Journals (Sweden)

    Duncan K Ralph

    2016-10-01

    Full Text Available The human immune system depends on a highly diverse collection of antibody-making B cells. B cell receptor sequence diversity is generated by a random recombination process called "rearrangement" forming progenitor B cells, then a Darwinian process of lineage diversification and selection called "affinity maturation." The resulting receptors can be sequenced in high throughput for research and diagnostics. Such a collection of sequences contains a mixture of various lineages, each of which may be quite numerous, or may consist of only a single member. As a step to understanding the process and result of this diversification, one may wish to reconstruct lineage membership, i.e. to cluster sampled sequences according to which came from the same rearrangement events. We call this clustering problem "clonal family inference." In this paper we describe and validate a likelihood-based framework for clonal family inference based on a multi-hidden Markov Model (multi-HMM framework for B cell receptor sequences. We describe an agglomerative algorithm to find a maximum likelihood clustering, two approximate algorithms with various trade-offs of speed versus accuracy, and a third, fast algorithm for finding specific lineages. We show that under simulation these algorithms greatly improve upon existing clonal family inference methods, and that they also give significantly different clusters than previous methods when applied to two real data sets.

  17. Prognostic significance of metallothionein in B-cell lymphomas

    DEFF Research Database (Denmark)

    Poulsen, Christian Bjørn; Borup, Rehannah; Borregaard, Niels

    2006-01-01

    -cell (ABC) and 3 of 9 type-3 lesions. In contrast, MT mRNA was low to undetectable in 16 germinal center B-cell (GCB)-type DLBCLs. Only 1 of 15 patients with up-regulated MT mRNA achieved a sustained remission, suggesting that up-regulated MT mRNA constitutes a significant risk factor for treatment failure...

  18. Lymphoma classification update: B-cell non-Hodgkin lymphomas.

    Science.gov (United States)

    Jiang, Manli; Bennani, N Nora; Feldman, Andrew L

    2017-05-01

    Lymphomas are classified based on the normal counterpart, or cell of origin, from which they arise. Because lymphocytes have physiologic immune functions that vary both by lineage and by stage of differentiation, the classification of lymphomas arising from these normal lymphoid populations is complex. Recent genomic data have contributed additional complexity. Areas covered: Lymphoma classification follows the World Health Organization (WHO) system, which reflects international consensus and is based on pathological, genetic, and clinical factors. A 2016 revision to the WHO classification of lymphoid neoplasms recently was reported. The present review focuses on B-cell non-Hodgkin lymphomas, the most common group of lymphomas, and summarizes recent changes most relevant to hematologists and other clinicians who care for lymphoma patients. Expert commentary: Lymphoma classification is a continually evolving field that needs to be responsive to new clinical, pathological, and molecular understanding of lymphoid neoplasia. Among the entities covered in this review, the 2016 revision of the WHO classification particularly impact the subclassification and genetic stratification of diffuse large B-cell lymphoma and high-grade B-cell lymphomas, and reflect evolving criteria and nomenclature for indolent B-cell lymphomas and lymphoproliferative disorders.

  19. Clinical aspects of lower leg compartment syndrome

    NARCIS (Netherlands)

    Brand, Johan Gerard Henric van den

    2004-01-01

    A compartment syndrome is a condition in which increased pressure within a limited space compromises the circulation and function of tissues within that space. Although pathofysiology is roughly similar in chronic exertional and acute compartment syndrome of the lower leg, the clinical

  20. Critical role for thymic CD19+CD5+CD1dhiIL-10+ regulatory B cells in immune homeostasis.

    Science.gov (United States)

    Xing, Chen; Ma, Ning; Xiao, He; Wang, Xiaoqian; Zheng, Mingke; Han, Gencheng; Chen, Guojiang; Hou, Chunmei; Shen, Beifen; Li, Yan; Wang, Renxi

    2015-03-01

    This study tested the hypothesis that besides the spleen, LNs, peripheral blood, and thymus contain a regulatory IL-10-producing CD19(+)CD5(+)CD1d(high) B cell subset that may play a critical role in the maintenance of immune homeostasis. Indeed, this population was identified in the murine thymus, and furthermore, when cocultured with CD4(+) T cells, this population of B cells supported the maintenance of CD4(+)Foxp3(+) Tregs in vitro, in part, via the CD5-CD72 interaction. Mice homozygous for Cd19(Cre) (CD19(-/-)) express B cells with impaired signaling and humoral responses. Strikingly, CD19(-/-) mice produce fewer CD4(+)Foxp3(+) Tregs and a greater percentage of CD4(+)CD8(-) and CD4(-)CD8(+) T cells. Consistent with these results, transfer of thymic CD19(+)CD5(+)CD1d(hi) B cells into CD19(-/-) mice resulted in significantly up-regulated numbers of CD4(+)Foxp3(+) Tregs with a concomitant reduction in CD4(+)CD8(-) and CD4(-)CD8(+) T cell populations in the thymus, spleen, and LNs but not in the BM of recipient mice. In addition, thymic CD19(+)CD5(+)CD1d(hi) B cells significantly suppressed autoimmune responses in lupus-like mice via up-regulation of CD4(+)Foxp3(+) Tregs and IL-10-producing Bregs. This study suggests that thymic CD19(+)CD5(+)CD1d(hi)IL-10(+) Bregs play a critical role in the maintenance of immune homeostasis. © Society for Leukocyte Biology.

  1. Assessment of selected B cells populations in the workers of X-ray departments

    Directory of Open Access Journals (Sweden)

    Piotr Kłuciński

    2014-08-01

    Full Text Available Objectives: Workers of X-ray departments are occupationally exposed to long-term low levels of ionizing radiation (LLIR, which may affect their humoral immunity. The aim of the study was to assess the influence of LLIR on the number and proportion of B cells (CD19+, B1 cells (CD5+CD19+ and memory B cells (CD27+CD19+ in peripheral blood of such workers. Materials and Methods: In the study group of 47 X-ray departments workers and the control group consisting of 38 persons, the number and percentage of CD19+, CD5+CD19+, CD27+CD19+ cells as well as CD5+CD19+/CD19+ and CD27+CD19+/CD19+ cell ratios were assessed using flow cytometry. Additionally, the study group was divided into 2 groups by the length of employment below and over 15 years and analysis adjusted for age and smoking habit was performed. Results: The total number of CD19+ cells showed significant increase in the group of workers in comparison with the persons from the control group, whereas the percentage of CD5+CD19+ cells as well as CD27+CD19+/CD19+ and CD5+CD19+/CD19+ cell ratios were lower. Percentage, number of CD5+CD19+ cells and CD5+CD19+/CD19+ cell ratio were significantly lower in the workers with length of employment longer than 15 years in comparison with those employed below 15 years. Moreover, we found positive associations between the number of CD19+ cells and employment as well as smoking habit, whereas the number of CD5+CD19+ cells was positively associated with cigarette smoking alone. Percentage of CD5+CD19+ cells as well as CD5+CD19+/CD19+ and CD27+CD19+/CD19+ cell ratios were negatively correlated with employment. Conclusions: The study suggests association between the suppressive influence of low level ionizing radiation on circulating in peripheral blood, especially of B1 cells as well as of memory B cells, in workers of X-ray units, which is adverse in relation to microbiological threat.

  2. Switched Memory B Cells Are Increased in Oligoarticular and Polyarticular Juvenile Idiopathic Arthritis and Their Change Over Time Is Related to Response to Tumor Necrosis Factor Inhibitors.

    Science.gov (United States)

    Marasco, Emiliano; Aquilani, Angela; Cascioli, Simona; Moneta, Gian Marco; Caiello, Ivan; Farroni, Chiara; Giorda, Ezio; D'Oria, Valentina; Marafon, Denise Pires; Magni-Manzoni, Silvia; Carsetti, Rita; De Benedetti, Fabrizio

    2018-04-01

    To investigate whether abnormalities in B cell subsets in patients with juvenile idiopathic arthritis (JIA) correlate with clinical features and response to treatment. A total of 109 patients diagnosed as having oligoarticular JIA or polyarticular JIA were enrolled in the study. B cell subsets in peripheral blood and synovial fluid were analyzed by flow cytometry. Switched memory B cells were significantly increased in patients compared to age-matched healthy controls (P < 0.0001). When patients were divided according to age at onset of JIA, in patients with early-onset disease (presenting before age 6 years) the expansion in switched memory B cells was more pronounced than that in patients with late-onset disease and persisted throughout the disease course. In longitudinal studies, during methotrexate (MTX) treatment, regardless of the presence or absence of active disease, the number of switched memory B cells increased significantly (median change from baseline 36% [interquartile range {IQR} 15, 66]). During treatment with MTX plus tumor necrosis factor inhibitors (TNFi), in patients maintaining disease remission, the increase in switched memory B cells was significantly lower than that in patients who experienced active disease (median change from baseline 4% [IQR -6, 32] versus 41% [IQR 11, 73]; P = 0.004). The yearly rate of increases in switched memory B cells was 1.5% in healthy controls, 1.2% in patients who maintained remission during treatment with MTX plus TNFi, 4.7% in patients who experienced active disease during treatment with MTX plus TNFi, and ~4% in patients treated with MTX alone. Switched memory B cells expand during the disease course at a faster rate in JIA patients than in healthy children. This increase is more evident in patients with early-onset JIA. TNFi treatment inhibits this increase in patients who achieve and maintain remission, but not in those with active disease. © 2018, American College of Rheumatology.

  3. Type I CD20 Antibodies Recruit the B Cell Receptor for Complement-Dependent Lysis of Malignant B Cells

    NARCIS (Netherlands)

    Engelberts, Patrick J.; Voorhorst, Marleen; Schuurman, Janine; van Meerten, Tom; Bakker, Joost M.; Vink, Tom; Mackus, Wendy J. M.; Breij, Esther C. W.; Derer, Stefanie; Valerius, Thomas; van de Winkel, Jan G. J.; Parren, Paul W. H. I.; Beurskens, Frank J.

    2016-01-01

    Human IgG1 type I CD20 Abs, such as rituximab and ofatumumab (OFA), efficiently induce complement-dependent cytotoxicity (CDC) of CD20(+) B cells by binding of C1 to hexamerized Fc domains. Unexpectedly, we found that type I CD20 Ab F(ab ')2 fragments, as well as C1q-binding-deficient IgG mutants,

  4. Assessment of CD37 B-cell antigen and cell of origin significantly improves risk prediction in diffuse large B-cell lymphoma

    DEFF Research Database (Denmark)

    Xu-Monette, Zijun Y; Li, Ling; Byrd, John C

    2016-01-01

    CD37 (tetraspanin TSPAN26) is a B-cell surface antigen widely expressed on mature B cells. CD37 is involved in immune regulation and tumor suppression but its function has not been fully elucidated. We assessed CD37 expression in de novo diffuse large B-cell lymphoma (DLBCL), and investigated its...

  5. 324 Facility B-cell quality process plan

    International Nuclear Information System (INIS)

    Carlson, J.L.

    1998-01-01

    B-Cell is currently being cleaned out (i.e., removal of equipment, fixtures and residual radioactive materials) and deactivated. TPA Milestone M-89-02 dictates that all mixed waste and equipment be removed from B-Cell by 5/31/99. The following sections describe the major activities that remain for completion of the TPA milestone. These include: Size Reduce Tank 119 and Miscellaneous Equipment; Load and Ship Low-Level Waste; Remove and Size Reduce the 1B Rack; Collect Dispersible Material from Cell Floor; Remove and Size Reduce the 2A Rack; Size Reduce the 1A Rack; Load and Ship Mixed Waste to PUREX Tunnels; and Move Spent Fuel to A-Cell;

  6. Rituximab and chemotherapy in diffuse large B-cell lymphoma.

    Science.gov (United States)

    Sonet, Anne; Bosly, André

    2009-06-01

    Rituximab is an anti-CD20 chimeric monoclonal antibody with activity in nearly all subtypes of B-cell lymphomas. Association of rituximab with chemotherapy (mostly the cyclophosphamide, doxorubicin, vincristine and prednisolone [CHOP] regimen) in diffuse large B-cell lymphoma (DLBCL) represents an extraordinary revolution in the prognosis of DLBCL, and is the new standard of therapy in elderly and young, low-risk patients. Despite the lack of randomized, clinical trials in younger patients with high risk, rituximab is also a standard of care in these patients in clinical practice, at least in North America. The practice is based on observational trials (e.g., the British Columbia Registry) and the missing logic in classifying patients as 'younger' or 'older': 60 years old or 65 years old. In Europe, trials are ongoing to establish the best treatment for young, high-risk patients. Association of rituximab and chemotherapy deeply modifies prognostic factors defined before the rituximab era.

  7. Th1 and Th2 help for B cells

    DEFF Research Database (Denmark)

    Poudrier, J; Owens, T

    1995-01-01

    that IL-5 (125 U/ml) synergizes with Th1 cells to induce B cell responses to IL-2, that are maintained following T-cell removal, e.g. autonomous. Th1 help in the absence of IL-5 resulted in weak or undetectable responses following T cell removal. The mechanism of IL-5 synergy involved persistence of IL-2R...... anti-Ig did not circumvent the need for IL-5 for autonomous IL-2 responses. Consistent with the above, interaction with an IL-5-producing Th2 clone induced strong autonomous B cell responses to IL-2. Qualitative differences of Th2 help over that of Th1 may thus be attributable to their differential...

  8. T. B-cell subpopulation in patients with malignant diseases

    International Nuclear Information System (INIS)

    Ogawa, Motoyoshi; Goto, Tatsuhiko; Naruto, Mamiko.

    1978-01-01

    T, B cells in the peripheural blood of patients with malignant diseases were investigated. The percentages of T cells in patients with malignant lymphomas correlated to the extent of disease determined by clinical stagings of Ann Arbor's classification, in stages III and IV T-cells decreased to compare with those in stages I and II, while B-cells did not show any changes. Absolute numbers of lymphocytes, blastogenesis induced by PHA or PWM decreased remarkably during combination chemotherapies and during radiotherapy whereas the percentages of T-cells measuring in the same patients did not influenced consistently by these treatments. The DNA pattern of lymphocytes during treatments was examined by Flow-Microphotometry and the result suggested that those lymphocytes were damaged by treatments and subsequently they were refractory to the action of mitogens. The results indicate that selective timing needs between chemotherapy and immunotherapy. (auth.)

  9. Epigenetic Impact on EBV Associated B-Cell Lymphomagenesis

    Directory of Open Access Journals (Sweden)

    Shatadru Ghosh Roy

    2016-11-01

    Full Text Available Epigenetic modifications leading to either transcriptional repression or activation, play an indispensable role in the development of human cancers. Epidemiological study revealed that approximately 20% of all human cancers are associated with tumor viruses. Epstein-Barr virus (EBV, the first human tumor virus, demonstrates frequent epigenetic alterations on both viral and host genomes in associated cancers—both of epithelial and lymphoid origin. The cell type-dependent different EBV latent gene expression patterns appear to be determined by the cellular epigenetic machinery and similarly viral oncoproteins recruit epigenetic regulators in order to deregulate the cellular gene expression profile resulting in several human cancers. This review elucidates the epigenetic consequences of EBV–host interactions during development of multiple EBV-induced B-cell lymphomas, which may lead to the discovery of novel therapeutic interventions against EBV-associated B-cell lymphomas by alteration of reversible patho-epigenetic markings.

  10. Bilateral proliferative retinopathy in B-cell acute lymphoblastic leukemia

    Directory of Open Access Journals (Sweden)

    Devesh Kumawat

    2018-01-01

    Full Text Available A 4-year-old child with B-cell acute lymphoblastic leukemia presented with vitreous hemorrhage due to proliferative retinopathy in both eyes. Pars plana vitrectomy was performed in both eyes to clear nonresolving vitreous hemorrhage after systemic stabilization. Visual recovery was limited by the disc drag in the right eye and subfoveal exudation in the left eye. Etiopathogenesis and management of proliferative retinopathy in acute leukemias are discussed.

  11. Genetics and Pathogenesis of Diffuse Large B-Cell Lymphoma.

    Science.gov (United States)

    Schmitz, Roland; Wright, George W; Huang, Da Wei; Johnson, Calvin A; Phelan, James D; Wang, James Q; Roulland, Sandrine; Kasbekar, Monica; Young, Ryan M; Shaffer, Arthur L; Hodson, Daniel J; Xiao, Wenming; Yu, Xin; Yang, Yandan; Zhao, Hong; Xu, Weihong; Liu, Xuelu; Zhou, Bin; Du, Wei; Chan, Wing C; Jaffe, Elaine S; Gascoyne, Randy D; Connors, Joseph M; Campo, Elias; Lopez-Guillermo, Armando; Rosenwald, Andreas; Ott, German; Delabie, Jan; Rimsza, Lisa M; Tay Kuang Wei, Kevin; Zelenetz, Andrew D; Leonard, John P; Bartlett, Nancy L; Tran, Bao; Shetty, Jyoti; Zhao, Yongmei; Soppet, Dan R; Pittaluga, Stefania; Wilson, Wyndham H; Staudt, Louis M

    2018-04-12

    Diffuse large B-cell lymphomas (DLBCLs) are phenotypically and genetically heterogeneous. Gene-expression profiling has identified subgroups of DLBCL (activated B-cell-like [ABC], germinal-center B-cell-like [GCB], and unclassified) according to cell of origin that are associated with a differential response to chemotherapy and targeted agents. We sought to extend these findings by identifying genetic subtypes of DLBCL based on shared genomic abnormalities and to uncover therapeutic vulnerabilities based on tumor genetics. We studied 574 DLBCL biopsy samples using exome and transcriptome sequencing, array-based DNA copy-number analysis, and targeted amplicon resequencing of 372 genes to identify genes with recurrent aberrations. We developed and implemented an algorithm to discover genetic subtypes based on the co-occurrence of genetic alterations. We identified four prominent genetic subtypes in DLBCL, termed MCD (based on the co-occurrence of MYD88 L265P and CD79B mutations), BN2 (based on BCL6 fusions and NOTCH2 mutations), N1 (based on NOTCH1 mutations), and EZB (based on EZH2 mutations and BCL2 translocations). Genetic aberrations in multiple genes distinguished each genetic subtype from other DLBCLs. These subtypes differed phenotypically, as judged by differences in gene-expression signatures and responses to immunochemotherapy, with favorable survival in the BN2 and EZB subtypes and inferior outcomes in the MCD and N1 subtypes. Analysis of genetic pathways suggested that MCD and BN2 DLBCLs rely on "chronic active" B-cell receptor signaling that is amenable to therapeutic inhibition. We uncovered genetic subtypes of DLBCL with distinct genotypic, epigenetic, and clinical characteristics, providing a potential nosology for precision-medicine strategies in DLBCL. (Funded by the Intramural Research Program of the National Institutes of Health and others.).

  12. Abdominal compartment syndrome with acute reperfusion syndrome

    International Nuclear Information System (INIS)

    Maleeva, A.

    2017-01-01

    Abdominal compartment syndrome was recognized clinically in the 19th century when Marey and Burt observed its association with declines in respiratory function. Abdominal compartment syndrome is first used as a medical terminology from Fietsman in a case of ruptured abdominal aortic aneurysm. A condition caused by abnormally increased pressure within the abdomen. Causes of abdominal compartment syndrome include trauma, surgery, or infection. Common symptoms: abdominal distension, fast heart rate, insufficient urine production, or low blood pressure Medical procedure: nasogastric intubation Surgery: laparotomy Specialists: radiologist, primary care provider (PCP), surgeon, and emergency medicine doctor [6, 10]. Keywords: Stomach. Gastroparesis . Diabetes Mellitus [bg

  13. The small FOXP1 isoform predominantly expressed in activated B cell-like diffuse large B-cell lymphoma and full-length FOXP1 exert similar oncogenic and transcriptional activity in human B cells.

    Science.gov (United States)

    van Keimpema, Martine; Grüneberg, Leonie J; Schilder-Tol, Esther J M; Oud, Monique E C M; Beuling, Esther A; Hensbergen, Paul J; de Jong, Johann; Pals, Steven T; Spaargaren, Marcel

    2017-03-01

    The forkhead transcription factor FOXP1 is generally regarded as an oncogene in activated B cell-like diffuse large B-cell lymphoma. Previous studies have suggested that a small isoform of FOXP1 rather than full-length FOXP1, may possess this oncogenic activity. Corroborating those studies, we herein show that activated B cell-like diffuse large B-cell lymphoma cell lines and primary activated B cell-like diffuse large B-cell lymphoma cells predominantly express a small FOXP1 isoform, and that the 5'-end of the Foxp1 gene is a common insertion site in murine lymphomas in leukemia virus- and transposon-mediated insertional mutagenesis screens. By combined mass spectrometry, (quantative) reverse transcription polymerase chain reaction/sequencing, and small interfering ribonucleic acid-mediated gene silencing, we determined that the small FOXP1 isoform predominantly expressed in activated B cell-like diffuse large B-cell lymphoma lacks the N-terminal 100 amino acids of full-length FOXP1. Aberrant overexpression of this FOXP1 isoform (ΔN100) in primary human B cells revealed its oncogenic capacity; it repressed apoptosis and plasma cell differentiation. However, no difference in potency was found between this small FOXP1 isoform and full-length FOXP1. Furthermore, overexpression of full-length FOXP1 or this small FOXP1 isoform in primary B cells and diffuse large B-cell lymphoma cell lines resulted in similar gene regulation. Taken together, our data indicate that this small FOXP1 isoform and full-length FOXP1 have comparable oncogenic and transcriptional activity in human B cells, suggesting that aberrant expression or overexpression of FOXP1, irrespective of the specific isoform, contributes to lymphomagenesis. These novel insights further enhance the value of FOXP1 for the diagnostics, prognostics, and treatment of diffuse large B-cell lymphoma patients. Copyright© Ferrata Storti Foundation.

  14. Memory control by the B cell antigen receptor.

    Science.gov (United States)

    Engels, Niklas; Wienands, Jürgen

    2018-05-01

    The generation of memory B cells (MBCs) that have undergone immunoglobulin class switching from IgM, which dominates primary antibody responses, to other immunoglobulin isoforms is a hallmark of immune memory. Hence, humoral immunological memory is characterized by the presence of serum immunoglobulins of IgG subtypes known as the γ-globulin fraction of blood plasma proteins. These antibodies reflect the antigen experience of B lymphocytes and their repeated triggering. In fact, efficient protection against a previously encountered pathogen is critically linked to the production of pathogen-specific IgG molecules even in those cases where the primary immune response required cellular immunity, for example, T cell-mediated clearance of intracellular pathogens such as viruses. Besides IgG, also IgA and IgE can provide humoral immunity depending on the microbe's nature and infection route. The molecular mechanisms underlying the preponderance of switched immunoglobulin isotypes during memory antibody responses are a matter of active and controversial debate. Here, we summarize the phenotypic characteristics of distinct MBC subpopulations and discuss the decisive roles of different B cell antigen receptor isotypes for the functional traits of class-switched B cell populations. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. B cell remote-handled waste shipment cask alternatives study

    International Nuclear Information System (INIS)

    RIDDELLE, J.G.

    1999-01-01

    The decommissioning of the 324 Facility B Cell includes the onsite transport of grouted remote-handled radioactive waste from the 324 Facility to the 200 Areas for disposal. The grouted waste has been transported in the leased ATG Nuclear Services 3-82B Radioactive Waste Shipping Cask (3-82B cask). Because the 3-82B cask is a U.S. Nuclear Regulatory Commission (NRC)-certified Type B shipping cask, the lease cost is high, and the cask operations in the onsite environment may not be optimal. An alternatives study has been performed to develop cost and schedule information on alternative waste transportation systems to assist in determining which system should be used in the future. Five alternatives were identified for evaluation. These included continued lease of the 3-82B cask, fabrication of a new 3-82B cask, development and fabrication of an onsite cask, modification of the existing U.S. Department of Energy-owned cask (OH-142), and the lease of a different commercially available cask. Each alternative was compared to acceptance criteria for use in the B Cell as an initial screening. Only continued leasing of the 3-82B cask, fabrication of a new 3-82B cask, and the development and fabrication of an onsite cask were found to meet all of the B Cell acceptance criteria

  16. Quantitative regulation of B cell division destiny by signal strength.

    Science.gov (United States)

    Turner, Marian L; Hawkins, Edwin D; Hodgkin, Philip D

    2008-07-01

    Differentiation to Ab secreting and isotype-switched effector cells is tightly linked to cell division and therefore the degree of proliferation strongly influences the nature of the immune response. The maximum number of divisions reached, termed the population division destiny, is stochastically distributed in the population and is an important parameter in the quantitative outcome of lymphocyte responses. In this study, we further assessed the variables that regulate B cell division destiny in vitro in response to T cell- and TLR-dependent stimuli. Both the concentration and duration of stimulation were able to regulate the average maximum number of divisions undergone for each stimulus. Notably, a maximum division destiny was reached during provision of repeated saturating stimulation, revealing that an intrinsic limit to proliferation exists even under these conditions. This limit was linked directly to division number rather than time of exposure to stimulation and operated independently of the survival regulation of the cells. These results demonstrate that a B cell population's division destiny is regulable by the stimulatory conditions up to an inherent maximum value. Division destiny is a crucial parameter in regulating the extent of B cell responses and thereby also the nature of the immune response mounted.

  17. Defective Circulating Regulatory B Cells in Patients with Dilated Cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Jiao Jiao

    2018-03-01

    Full Text Available Background/Aims: Newly identified IL-10-producing regulatory B cells (Bregs have been shown to play an important role in the suppression of immune responses. Chronic immune activation participates in the pathogenesis of dilated cardiomyopathy (DCM but whether Bregs are involved in its development remains unclear. We aimed to investigate the circulating frequency and function of Bregs in DCM. Methods: In total, 35 DCM patients (20 men and 15 women and 44 healthy controls (23 men and 21 women were included in the experiment, and the frequency of Bregs was detected using flow cytometry. Results: According to our results, the frequency of circulating IL-10-producing Bregs was significantly lower in DCM patients compared with healthy controls. Furthermore, the CD24hiCD27+ B cell subset in which IL-10-producing Bregs were mainly enriched from DCM patients showed impaired IL-10 expression and a decreased ability to suppress the TNF-α production of CD4+CD25- Tconv cells and to maintain Tregs differentiation. Correlation analysis showed that the frequency of IL-10-producing Bregs and the suppressive function of CD24hiCD27+ B cells were positively correlated with left ventricular ejection fraction and negatively correlated with NT-proBNP in DCM patients. Conclusions: In conclusion, the reduced frequency and impaired functions suggest a potential role of Bregs in the development of DCM.

  18. Generation of memory B cells and their reactivation.

    Science.gov (United States)

    Inoue, Takeshi; Moran, Imogen; Shinnakasu, Ryo; Phan, Tri Giang; Kurosaki, Tomohiro

    2018-05-01

    The successful establishment of humoral memory response depends on at least two layers of defense. Pre-existing protective antibodies secreted by long-lived plasma cells act as a first line of defense against reinfection ("constitutive humoral memory"). Previously, a second line of defense in which pathogen-experienced memory B cells are rapidly reactivated to produce antibodies ("reactive humoral memory"), was considered as simply a back-up system for the first line (particularly for re-infection with homologous viruses). However, in the case of re-infection with similar but different strains of viruses, or in response to viral escape mutants, the reactive humoral memory plays a crucial role. Here, we review recent progress in our understanding of how memory B cells are generated in the pre-GC stage and during the GC reaction, and how these memory B cells are robustly reactivated with the help of memory Tfh cells to generate the secondary antibody response. In addition, we discuss how these advances may be relevant to the quest for a vaccine that can induce broadly reactive antibodies against influenza and HIV. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. B-cell-depleting Therapy in Systemic Lupus Erythematosus

    Science.gov (United States)

    Ramos-Casals, Manuel; Sanz, Iñaki; Bosch, Xavier; Stone, John H.; Khamashta, Munther A.

    2014-01-01

    The emergence of a new class of agents (B-cell-depleting therapies) has opened a new era in the therapeutic approach to systemic lupus erythematosus, with belimumab being the first drug licensed for use in systemic lupus erythematosus in more than 50 years. Four agents deserve specific mention: rituximab, ocrelizumab, epratuzumab, and belimumab. Controlled trials have shown negative results for rituximab, promising results for epratuzumab, and positive results for belimumab. Despite these negative results, rituximab is the most-used agent in patients who do not respond or are intolerant to standard therapy and those with life-threatening presentations. B-cell-depleting agents should not be used in patients with mild disease and should be tailored according to individual patient characteristics, including ethnicity, organ involvement, and the immunological profile. Forthcoming studies of B-cell-directed strategies, particularly data from investigations of off-label rituximab use and postmarketing studies of belimumab, will provide new insights into the utility of these treatments in the routine management of patients with systemic lupus erythematosus. PMID:22444096

  20. TRPM4 expression is associated with activated B cell subtype and poor survival in diffuse large B cell lymphoma

    DEFF Research Database (Denmark)

    Loo, Suet K; Ch'ng, Ewe S; Md Salleh, Md Salzihan

    2017-01-01

    to investigate TRPM4 protein expression pattern in non-malignant tissues and DLBCL cases, and its association with clinico-demographic parameters and survival in DLBCL. METHODS AND RESULTS: Analysis of publicly available DLBCL microarray data sets showed that TRPM4 transcripts were up-regulated in DLBCL compared...... to normal germinal centre B (GCB) cells, were expressed more highly in the activated B cell-like DLBCL (ABC-DLBCL) subtype and higher TRPM4 transcripts conferred worse overall survival (OS) in R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone)-treated DLBCL cases (P ... immunohistochemical analysis showed that TRPM4 was expressed in various human tissues but not in normal B cells within lymphoid tissues (reactive tonsil, lymph node and appendix). TRPM4 protein was present in 26% (n = 49 of 189) of our cohort of R-CHOP-treated DLBCL cases and this was associated significantly...

  1. Abdominal Compartment Syndrome in Surgical Patients

    African Journals Online (AJOL)

    abdominal hypertension and abdominal compartment syndrome, affect ... timely surgical intervention is crucial. Key words: .... On the second postoperative day, he was noted to be restless ... Although surgery is very effective in managing ACS.

  2. Compartment syndrome in a labrador retriever

    International Nuclear Information System (INIS)

    Williams, J.; Bailey, M.Q.; Schertel, E.R.; Valentine, A.

    1994-01-01

    Compartment syndrome is an elevation of interstitial pressure in a closed osseofascial compartment that results in microvascular compromise. This report documents a clinical syndrome in the crus of a fourteen-month-old intact male Labrador Retriever which was consistent with trauma-induced compartment syndrome. A six month history of recurring trauma or complications resulted in the need for referral. Survey radiography and ultrasonography aided in the diagnosis, but the definitive answer was provided by femoral angiography. The patient was successfully treated and was discharged with normal limb function. One year later, there were no complications observed. Compartment syndrome is not uncommon in humans, and is routinely considered in certain blunt and most penetrating traumas. However, few reports of this complication in animals are found

  3. Multi-compartment microscopic diffusion imaging

    OpenAIRE

    Kaden, Enrico; Kelm, Nathaniel D.; Carson, Robert P.; Does, Mark D.; Alexander, Daniel C.

    2016-01-01

    This paper introduces a multi-compartment model for microscopic diffusion anisotropy imaging. The aim is to estimate microscopic features specific to the intra- and extra-neurite compartments in nervous tissue unconfounded by the effects of fibre crossings and orientation dispersion, which are ubiquitous in the brain. The proposed MRI method is based on the Spherical Mean Technique (SMT), which factors out the neurite orientation distribution and thus provides direct estimates of the microsco...

  4. Type i CD20 antibodies recruit the B cell receptor for complement-dependent lysis of malignant B cells

    DEFF Research Database (Denmark)

    Engelberts, P. J.; Voorhorst, M.; Schuurman, J.

    2016-01-01

    . We hypothesized that CD20 Ab-induced clustering of the IgM or IgG BCR was involved in accessory CDC. Indeed, accessory CDC was consistently observed in B cell lines expressing an IgM BCR and in some cell lines expressing an IgG BCR, but it was absent in BCR- B cell lines. A direct relationship...... between BCR expression and accessory CDC was established by transfecting the BCR into CD20+ cells: OFA-F(ab')2 fragments were able to induce CDC in the CD20+BCR+ cell population, but not in the CD20+BCR- population. Importantly, OFA-F(ab')2 fragments were able to induce CDC ex vivo in malignant B cells...... isolated from patients with mantle cell lymphoma and Waldenström macroglobulinemia. In summary, accessory CDC represents a novel effector mechanism that is dependent on type I CD20 Ab-induced BCR clustering. Accessory CDC may contribute to the excellent capacity of type I CD20 Abs to induce CDC...

  5. Splenic B cells and antigen-specific B cells process anti-Ig in a similar manner

    International Nuclear Information System (INIS)

    Myers, C.D.; Vitetta, E.S.

    1989-01-01

    B lymphocytes can process and present antigen to T cells. However, the fate of native antigen after its binding to specific B cells, i.e., the intracellular events involved in the processing and recycling of the antigenic fragments to the cell surface for antigen presentation, are not well understood. In the present study, we demonstrate that murine B cells degrade anti-Ig molecules bound to their surface and release acid soluble fragments into the supernatant. We also demonstrate that the kinetics of this process are identical for anti-mu, anti-delta, and anti-light chain antibodies, indicating that both surface IgM and surface IgD are equally effective in binding antigen and directing its processing. We also describe the effects of azide, chloroquine, and irradiation on this process. To extend these studies to the processing of specifically bound antigen, we demonstrate that highly purified trinitrophenyl antigen-binding cells degrade anti-Ig molecules with the same kinetics as unpurified splenic B cells. Thus, this purified population provides a suitable model system for the analysis of antigen degradation by antigen-specific cells

  6. 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

  7. Pathogenesis of herpes simplex virus in B cell-suppressed mice: the relative roles of cell-mediated and humoral immunity.

    Science.gov (United States)

    Kapoor, A K; Nash, A A; Wildy, P

    1982-07-01

    B cell responses of Balb/c mice were suppressed using sheep anti-mouse IgM serum. At 4 weeks, both B cell-suppressed and normal littermates were infected in the ear pinna with herpes simplex virus type 1 (HSV-1). The B cell-suppressed mice failed to produce neutralizing herpes antibodies in their sera but had a normal cell-mediated immunity (CMI) response as measured by a delayed hypersensitivity skin test. Although the infection was eliminated from the ear in both B cell-suppressed and normal mice by day 10 after infection, there was an indication that B cell-suppressed mice had a more florid primary infection of the peripheral and central nervous system and also a higher incidence of a latent infection. These results support the hypothesis that antibody is important in restricting the spread of virus to the central nervous system, whereas CMI is important in clearing the primary infection in the ear pinna.

  8. Ia-restricted B-B cell interaction. I. The MHC haplotype of bone marrow cells present during B cell ontogeny dictates the self-recognition specificity of B cells in the polyclonal B cell activation by a B cell differentiation factor, B151-TRF2

    International Nuclear Information System (INIS)

    Ono, S.; Takahama, Y.; Hamaoka, T.

    1987-01-01

    We have demonstrated that B cell recognition of Ia molecules is involved in polyclonal B cell differentiation by B151-TRF2. The present study was undertaken to examine the Ia recognition specificity of B151-TRF2-responsive B cells in fully major histocompatibility complex (MHC)-allogeneic P1----P2, semiallogeneic P1----(P1 x P2)F1, and double donor (P1 + P2)----(P1 x P2)F1 and (P1 + P2)----P1 radiation bone marrow chimeras. The B cells from both P1----P2 and P1----(P1 x P2)F1 chimeras could give rise to in vitro immunoglobulin M-producing cells upon stimulation with B151-TRF2 comparable in magnitude to that of normal P1 B cells, and their responses were inhibited by anti-I-AP1 but not by anti-I-AP2 monoclonal antibody even in the presence of mitomycin C-treated T cell-depleted P2 spleen cells as auxiliary cells. In contrast, the B151-TRF2 responses of P1 B cells isolated from both (P1 + P2)----(P1 x P2)F1 and (P1 + P2)----P1 double bone marrow chimeras became sensitive to the inhibition of not only anti-I-AP1 but also anti-I-AP2 monoclonal antibody only when the culture was conducted in the presence of P2 auxiliary cells, demonstrating that they adaptively differentiate to recognize as self-structures allogeneic as well as syngeneic Ia molecules. Moreover, the experiments utilizing B cells from H-2-congenic mice and B cell hybridoma clones as auxiliary cells revealed that B151-TRF2-responsive B cells recognize Ia molecules expressed on B cells. Taken together, these results demonstrate that B151-TRF2-responsive B cells recognize Ia molecules expressed by B cells as self-structures and that their self-recognition specificity is dictated by the MHC haplotype of bone marrow cells present during the B cell ontogeny but not by the MHC haplotype of a radiation-resistant host environment

  9. Quantifying changes in the cellular thiol-disulfide status during differentiation of B cells into antibody-secreting plasma cells

    DEFF Research Database (Denmark)

    Hansen, Rosa Rebecca Erritzøe; Otsu, Mieko; Braakman, Ineke

    2013-01-01

    by the differentiation, steady-state levels of glutathionylated protein thiols are less than 0.3% of the total protein cysteines, even in fully differentiated cells, and the overall protein redox state is not affected until late in differentiation, when large-scale IgM production is ongoing. A general expansion......Plasma cells produce and secrete massive amounts of disulfide-containing antibodies. To accommodate this load on the secretory machinery, the differentiation of resting B cells into antibody-secreting plasma cells is accompanied by a preferential expansion of the secretory compartments of the cells...... of the ER does not affect global protein redox status until an extensive production of cargo proteins has started....

  10. B cell receptor accessory molecule CD79α: characterisation and expression analysis in a cartilaginous fish, the spiny dogfish (Squalus acanthias).

    Science.gov (United States)

    Li, Ronggai; Wang, Tiehui; Bird, Steve; Zou, Jun; Dooley, Helen; Secombes, Christopher J

    2013-06-01

    CD79α (also known as Igα) is a component of the B cell antigen receptor complex and plays an important role in B cell signalling. The CD79α protein is present on the surface of B cells throughout their life cycle, and is absent on all other healthy cells, making it a highly reliable marker for B cells in mammals. In this study the spiny dogfish (Squalus acanthias) CD79α (SaCD79α) is described and its expression studied under constitutive and stimulated conditions. The spiny dogfish CD79α cDNA contains an open reading frame of 618 bp, encoding a protein of 205 amino acids. Comparison of the SaCD79α gene with that of other species shows that the gross structure (number of exons, exon/intron boundaries, etc.) is highly conserved across phylogeny. Additionally, analysis of the 5' flanking region shows SaCD79α lacks a TATA box and possesses binding sites for multiple transcription factors implicated in its B cell-specific gene transcription in other species. Spiny dogfish CD79α is most highly expressed in immune tissues, such as spleen, epigonal and Leydig organ, and its transcript level significantly correlates with those of spiny dogfish immunoglobulin heavy chains. Additionally, CD79α transcription is up-regulated, to a small but significant degree, in peripheral blood cells following stimulation with pokeweed mitogen. These results strongly indicate that, as in mammals, spiny dogfish CD79α is expressed by shark B cells where it associates with surface-bound immunoglobulin to form a fully functional BCR, and thus may serve as a pan-B cell marker in future shark immunological studies. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Zinc finger protein 521 antagonizes early B-cell factor 1 and modulates the B-lymphoid differentiation of primary hematopoietic progenitors.

    Science.gov (United States)

    Mega, Tiziana; Lupia, Michela; Amodio, Nicola; Horton, Sarah J; Mesuraca, Maria; Pelaggi, Daniela; Agosti, Valter; Grieco, Michele; Chiarella, Emanuela; Spina, Raffaella; Moore, Malcolm A S; Schuringa, Jan Jacob; Bond, Heather M; Morrone, Giovanni

    2011-07-01

    Zinc finger protein 521 (EHZF/ZNF521) is a multi-functional transcription co-factor containing 30 zinc fingers and an amino-terminal motif that binds to the nucleosome remodelling and histone deacetylase (NuRD) complex. ZNF521 is believed to be a relevant player in the regulation of the homeostasis of the hematopoietic stem/progenitor cell compartment, however the underlying molecular mechanisms are still largely unknown. Here, we show that this protein plays an important role in the control of B-cell development by inhibiting the activity of early B-cell factor-1 (EBF1), a master factor in B-lineage specification. In particular, our data demonstrate that: (1) ZNF521 binds to EBF1 via its carboxyl-terminal portion and this interaction is required for EBF1 inhibition; (2) NuRD complex recruitment by ZNF521 is not essential for the inhibition of transactivation of EBF1-dependent promoters; (3) ZNF521 represses EBF1 target genes in a human B-lymphoid molecular context; and (4) RNAi-mediated silencing of ZNF521/Zfp521 in primary human and murine hematopoietic progenitors strongly enhances the generation of B-lymphocytes in vitro. Taken together, our data indicate that ZNF521 can antagonize B-cell development and lend support to the notion that it may contribute to conserve the multipotency of primitive lympho-myeloid progenitors by preventing or delaying their EBF1-driven commitment toward the B-cell lineage.

  12. B-cell activation with CD40L or CpG measures the function of B-cell subsets and identifies specific defects in immunodeficient patients.

    Science.gov (United States)

    Marasco, Emiliano; Farroni, Chiara; Cascioli, Simona; Marcellini, Valentina; Scarsella, Marco; Giorda, Ezio; Piano Mortari, Eva; Leonardi, Lucia; Scarselli, Alessia; Valentini, Diletta; Cancrini, Caterina; Duse, Marzia; Grimsholm, Ola; Carsetti, Rita

    2017-01-01

    Around 65% of primary immunodeficiencies are antibody deficiencies. Functional tests are useful tools to study B-cell functions in vitro. However, no accepted guidelines for performing and evaluating functional tests have been issued yet. Here, we report our experience on the study of B-cell functions in infancy and throughout childhood. We show that T-independent stimulation with CpG measures proliferation and differentiation potential of memory B cells. Switched memory B cells respond better than IgM memory B cells. On the other hand, CD40L, a T-dependent stimulus, does not induce plasma cell differentiation, but causes proliferation of naïve and memory B cells. During childhood, the production of plasmablasts in response to CpG increases with age mirroring the development of memory B cells. The response to CD40L does not change with age. In patients with selective IgA deficiency (SIgAD), we observed that switched memory B cells are reduced due to the absence of IgA memory B cells. In agreement, IgA plasma cells are not generated in response to CpG. Unexpectedly, B cells from SIgAD patients show a reduced proliferative response to CD40L. Our results demonstrate that functional tests are an important tool to assess the functions of the humoral immune system. © 2016 The Authors. European Journal of Immunology published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Intrinsic Plasma Cell Differentiation Defects in B Cell Expansion with NF-κB and T Cell Anergy Patient B Cells

    Directory of Open Access Journals (Sweden)

    Swadhinya Arjunaraja

    2017-08-01

    Full Text Available B cell Expansion with NF-κB and T cell Anergy (BENTA disease is a novel B cell lymphoproliferative disorder caused by germline, gain-of-function mutations in the lymphocyte scaffolding protein CARD11, which drives constitutive NF-κB signaling. Despite dramatic polyclonal expansion of naive and immature B cells, BENTA patients also present with signs of primary immunodeficiency, including markedly reduced percentages of class-switched/memory B cells and poor humoral responses to certain vaccines. Using purified naive B cells from our BENTA patient cohort, here we show that BENTA B cells exhibit intrinsic defects in B cell differentiation. Despite a profound in vitro survival advantage relative to normal donor B cells, BENTA patient B cells were severely impaired in their ability to differentiate into short-lived IgDloCD38hi plasmablasts or CD138+ long-lived plasma cells in response to various stimuli. These defects corresponded with diminished IgG antibody production and correlated with poor induction of specific genes required for plasma cell commitment. These findings provide important mechanistic clues that help explain both B cell lymphocytosis and humoral immunodeficiency in BENTA disease.

  14. Antibody repertoires in humanized NOD-scid-IL2Rγ(null mice and human B cells reveals human-like diversification and tolerance checkpoints in the mouse.

    Directory of Open Access Journals (Sweden)

    Gregory C Ippolito

    Full Text Available Immunodeficient mice reconstituted with human hematopoietic stem cells enable the in vivo study of human hematopoiesis. In particular, NOD-scid-IL2Rγ(null engrafted mice have been shown to have reasonable levels of T and B cell repopulation and can mount T-cell dependent responses; however, antigen-specific B-cell responses in this model are generally poor. We explored whether developmental defects in the immunoglobulin gene repertoire might be partly responsible for the low level of antibody responses in this model. Roche 454 sequencing was used to obtain over 685,000 reads from cDNA encoding immunoglobulin heavy (IGH and light (IGK and IGL genes isolated from immature, naïve, or total splenic B cells in engrafted NOD-scid-IL2Rγ(null mice, and compared with over 940,000 reads from peripheral B cells of two healthy volunteers. We find that while naïve B-cell repertoires in humanized mice are chiefly indistinguishable from those in human blood B cells, and display highly correlated patterns of immunoglobulin gene segment use, the complementarity-determining region H3 (CDR-H3 repertoires are nevertheless extremely diverse and are specific for each individual. Despite this diversity, preferential D(H-J(H pairings repeatedly occur within the CDR-H3 interval that are strikingly similar across all repertoires examined, implying a genetic constraint imposed on repertoire generation. Moreover, CDR-H3 length, charged amino-acid content, and hydropathy are indistinguishable between humans and humanized mice, with no evidence of global autoimmune signatures. Importantly, however, a statistically greater usage of the inherently autoreactive IGHV4-34 and IGKV4-1 genes was observed in the newly formed immature B cells relative to naïve B or total splenic B cells in the humanized mice, a finding consistent with the deletion of autoreactive B cells in humans. Overall, our results provide evidence that key features of the primary repertoire are shaped by

  15. Diffuse large B-cell lymphoma of the oral cavity

    International Nuclear Information System (INIS)

    Carlos Bortoluzzi, Marcelo

    2010-01-01

    The authors report a case of diffuse large B-cell lymphoma (DLBL) of the oral cavity. The patient was a 73-year-old white man who first presented at the Division of Stomatology with a large nodular mass in the hard palate and a nodular lesion in the upper lip, which were diagnosed as DLBL. The patient was treated with eight cycles of CHOP chemotherapy (cyclophosphamide, doxorubicin, vincristine and prednisone), but the disease recurred 22 months after the end of the therapy. Both primary sites hard palate and upper lip were involved again and the patient was resubmitted to chemotherapy. (author)

  16. B cell markers in Ph1-positive acute lymphoblastic leukemia.

    Science.gov (United States)

    Alimena, G; De Rossi, G; Gastaldi, R; Guglielmi, C; Mandelli, F

    1980-01-01

    A case of acute lymphoblastic leukemia (ALL) where the blast cells had B cell markers and displayed the presence of a typical Ph1 chromosome, originated by a standard t (9;22) translocation, is reported. Cytological and clinical aspects during the entire course of the disease were consistent with the diagnosis of ALL. Evidence of differentiation along a well-defined lymphoid cell line in a Ph1-positive cell confirms the presence of the Ph1 chromosome in conditions other than chronic granulocytic leukemia and shows that it possibly does not occur in an exclusively undifferentiated totipotent stem cell.

  17. The A-myb transcription factor in neoplastic and normal B cells.

    Science.gov (United States)

    Golay, J; Facchinetti, V; Ying, G; Introna, M

    1997-07-01

    The myb family of transcription factors has been strongly implicated in the regulation of cell growth and differentiation in the haematopoietic system. The v-myb oncogene, carried by avian defective retroviruses, causes leukaemias in the chicken and transforms haematopoietic cells in vitro. Its normal cellular equivalent c-myb, has been shown to promote the proliferation and block the differentiation of haematopoietic cells in several experimental models and is required for fetal haematopoiesis. Two other members of the family have been cloned more recently, A-myb and B-myb, which show sequence homology with c-myb in several domains, of which the DNA binding domain as well as other regulatory domains. Both have been shown to be transcription factors. B-myb is also involved in the control of proliferation and differentiation, but, unlike c-myb, it is expressed in many cell types. The third member of the family, A-myb, shows the most restricted pattern of expression, suggesting a very specific role for this transcription factor. A-myb is expressed in a subpopulation of normal B lymphocytes activated in vivo and localised in the germinal center of peripheral lymphoid organs and is not detected at significant levels in all other mature or immature haematopoietic populations studied, including bone marrow cells, T lymphocytes, granulocytes, monocytes, either at rest or after in vitro activation. These studies indicate that A-myb plays a role during a narrow window of normal B cell differentiation. A-myb expression has also been studied in a wide range of neoplastic B cells, representing the whole spectrum of B cell differentiation. A-myb is strongly expressed in Burkitt's lymphomas (BL) and slg+ B-acute lymphoblastic leukaemias (B-ALL) and not in all other leukaemias/lymphomas tested, with the exception of a subset of CLL (about 25% of cases). It is intriguing that the A-myb genome has been localised relatively close to the c-myc gene on chromosome 8, suggesting that

  18. CD47 limits antibody dependent phagocytosis against non-malignant B cells.

    Science.gov (United States)

    Gallagher, Sandra; Turman, Sean; Lekstrom, Kristen; Wilson, Susan; Herbst, Ronald; Wang, Yue

    2017-05-01

    Recent studies have demonstrated the importance of CD47 in protecting malignant B cells from antibody dependent cellular phagocytosis (ADCP). Combined treatment of anti-CD47 and -CD20 antibodies synergistically augment elimination of tumor B cells in xenograft mouse models. This has led to the development of novel reagents that can potentially enhance killing of malignant B cells in patients. B cell depleting therapy is also a promising treatment for autoimmune patients. In the current study, we aimed to investigate whether or not CD47 protects non-malignant B cells from ADCP. We show that CD47 is expressed on all B cells in mice, with the highest level on plasma cells in bone marrow and spleen. Although its expression is dispensable for B cell development in mice, CD47 on B cells limits antibody mediated phagocytosis. B cell depletion following in vivo anti-CD19 treatment is more efficient in CD47-/- mice than in wild type mice. In vitro, both naïve and activated B cells from CD47-/- mice are more sensitive to ADCP than wild type B cells. Lastly, we show in an ADCP assay that blocking CD47 can enhance anti-CD19 antibody mediated phagocytosis of wild type B cells. These results suggest that in addition to its already demonstrated benefit in cancer, targeting CD47 may be used as an adjunct in combination with B cell depletion antibodies for treatment of autoimmune diseases. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Anatomical variations within the deep posterior compartment of the leg and important clinical consequences.

    Science.gov (United States)

    Hislop, M; Tierney, P

    2004-09-01

    The management of musculoskeletal conditions makes up a large part of a sports medicine practitioner's practice. A thorough knowledge of anatomy is an essential component of the armament necessary to decipher the large number of potential conditions that may confront these practitioners. To cloud the issue further, anatomical variations may be present, such as supernumerary muscles, thickened fascial bands or variant courses of nerves and blood vessels, which can themselves manifest as acute or chronic conditions that lead to significant morbidity or limitation of activity. There are a number of contentious areas within the literature surrounding the anatomy of the leg, particularly involving the deep posterior compartment. Conditions such as chronic exertional compartment syndrome, tibial periostitis (shin splints), peripheral nerve entrapment and tarsal tunnel syndrome may all be affected by subtle anatomical variations. This paper primarily focuses on the deep posterior compartment of the leg and uses the gross dissection of cadaveric specimens to describe definitively the anatomy of the deep posterior compartment. Variant fascial attachments of flexor digitorum longus are documented and potential clinical sequelae such as chronic exertional compartment syndrome and tarsal tunnel syndrome are discussed.

  20. FcγRIIb on myeloid cells rather than on B cells protects from collagen-induced arthritis.

    Science.gov (United States)

    Yilmaz-Elis, A Seda; Ramirez, Javier Martin; Asmawidjaja, Patrick; van der Kaa, Jos; Mus, Anne-Marie; Brem, Maarten D; Claassens, Jill W C; Breukel, Cor; Brouwers, Conny; Mangsbo, Sara M; Boross, Peter; Lubberts, Erik; Verbeek, J Sjef

    2014-06-15

    Extensive analysis of a variety of arthritis models in germline KO mice has revealed that all four receptors for the Fc part of IgG (FcγR) play a role in the disease process. However, their precise cell type-specific contribution is still unclear. In this study, we analyzed the specific role of the inhibiting FcγRIIb on B lymphocytes (using CD19Cre mice) and in the myeloid cell compartment (using C/EBPαCre mice) in the development of arthritis induced by immunization with either bovine or chicken collagen type II. Despite their comparable anti-mouse collagen autoantibody titers, full FcγRIIb knockout (KO), but not B cell-specific FcγRIIb KO, mice showed a significantly increased incidence and severity of disease compared with wild-type control mice when immunized with bovine collagen. When immunized with chicken collagen, disease incidence was significantly increased in pan-myeloid and full FcγRIIb KO mice, but not in B cell-specific KO mice, whereas disease severity was only significantly increased in full FcγRIIb KO mice compared with incidence and severity in wild-type control mice. We conclude that, although anti-mouse collagen autoantibodies are a prerequisite for the development of collagen-induced arthritis, their presence is insufficient for disease development. FcγRIIb on myeloid effector cells, as a modulator of the threshold for downstream Ab effector pathways, plays a dominant role in the susceptibility to collagen-induced arthritis, whereas FcγRIIb on B cells, as a regulator of Ab production, has a minor effect on disease susceptibility. Copyright © 2014 by The American Association of Immunologists, Inc.

  1. Lack of galectin-3 disturbs mesenteric lymph node homeostasis and B cell niches in the course of Schistosoma mansoni infection.

    Directory of Open Access Journals (Sweden)

    Felipe L Oliveira

    Full Text Available Galectin-3 is a β-galactoside-binding protein that has been shown to regulate pathophysiological processes, including cellular activation, differentiation and apoptosis. Recently, we showed that galectin-3 acts as a potent inhibitor of B cell differentiation into plasma cells. Here, we have investigated whether galectin-3 interferes with the lymphoid organization of B cell compartments in mesenteric lymph nodes (MLNs during chronic schistosomiasis, using WT and galectin-3(-/- mice. Schistosoma mansoni synthesizes GalNAcβ1-4(Fucα1-3GlcNAc(Lac-DiNAc structures (N-acetylgalactosamine β1-4 N-acetylglucosamine, which are known to interact with galectin-3 and elicit an intense humoral response. Antigens derived from the eggs and adult worms are continuously drained to MLNs and induce a polyclonal B cell activation. In the present work, we observed that chronically-infected galectin-3(-/- mice exhibited a significant reduced amount of macrophages and B lymphocytes followed by drastic histological changes in B lymphocyte and plasma cell niches in the MLNs. The lack of galectin-3 favored an increase in the lymphoid follicle number, but made follicular cells more susceptible to apoptotic stimuli. There were an excessive quantity of apoptotic bodies, higher number of annexin V(+/PI(- cells, and reduced clearance of follicular apoptotic cells in the course of schistosomiasis. Here, we observed that galectin-3 was expressed in non-lymphoid follicular cells and its absence was associated with severe damage to tissue architecture. Thus, we convey new information on the role of galectin-3 in regulation of histological events associated with B lymphocyte and plasma cell niches, apoptosis, phagocytosis and cell cycle properties in the MLNs of mice challenged with S.mansoni.

  2. Reciprocal influence of B cells and tumor macro and microenvironments in the ApcMin/+ model of colorectal cancer.

    Science.gov (United States)

    Mion, Francesca; Vetrano, Stefania; Tonon, Silvia; Valeri, Viviana; Piontini, Andrea; Burocchi, Alessia; Petti, Luciana; Frossi, Barbara; Gulino, Alessandro; Tripodo, Claudio; Colombo, Mario P; Pucillo, Carlo E

    2017-01-01

    One of the most fascinating aspects of the immune system is its dynamism, meant as the ability to change and readapt according to the organism needs. Following an insult, we assist to the spontaneous organization of different immune cells which cooperate, locally and at distance, to build up an appropriate response. Throughout tumor progression, adaptations within the systemic tumor environment, or macroenvironment, result in the promotion of tumor growth, tumor invasion and metastasis to distal organs, but also to dramatic changes in the activity and composition of the immune system. In this work, we show the changes of the B-cell arm of the immune system following tumor progression in the Apc Min/+ model of colorectal cancer. Tumor macroenvironment leads to an increased proportion of total and IL-10-competent B cells in draining LNs while activates a differentiation route that leads to the expansion of IgA + lymphocytes in the spleen and peritoneum. Importantly, serum IgA levels were significantly higher in Apc Min/+ than Wt mice. The peculiar involvement of IgA response in the adenomatous transformation had correlates in the gut-mucosal compartment where IgA-positive elements increased from normal mucosa to areas of low grade dysplasia while decreasing upon overt carcinomatous transformation. Altogether, our findings provide a snapshot of the tumor education of B lymphocytes in the Apc Min/+ model of colorectal cancer. Understanding how tumor macroenvironment affects the differentiation, function and distribution of B lymphocytes is pivotal to the generation of specific therapies, targeted to switching B cells to an anti-, rather than pro-, tumoral phenotype.

  3. B-Cell Activation and Tolerance Mediated by B-Cell Receptor, Toll-Like Receptor, and Survival Signal Crosstalk in SLE Pathogenesis

    Science.gov (United States)

    2017-09-01

    Dec, 2016 "Integrating innate , adaptive, & survival signals to control B cell selection, homeostasis and tolerance" Pasteur Institute of Shanghai...secondary lymphoid tissues. Aging Dis. 2: 361–373. 8. Goenka, R., J. L. Scholz, M. S. Naradikian, and M. P. Cancro. 2014. Memory B cells form in aged...Scholz, and M. P. Cancro. 2011. A B- cell subset uniquely responsive to innate stimuli accumulates in aged mice. Blood 118: 1294–1304. 10. Rubtsov, A

  4. The Transcriptional Coactivator Bob1 Is Associated With Pathologic B Cell Responses in Autoimmune Tissue Inflammation

    NARCIS (Netherlands)

    Levels, Maria J.; Van Tok, Melissa N.; Cantaert, Tineke; Canete, Juan D.; Kroese, Frans G. M.; Germar, Kristine; Spits, Hergen; Baeten, Dominique L. P.; Yeremenko, Nataliya G.

    Objective. The molecular mechanisms steering abnormal B cell responses in autoimmune diseases remain poorly understood. We undertook this study to identify molecular switches controlling pathologic B cell responses in rheumatoid arthritis (RA). Methods. Candidate molecules were identified by gene

  5. Iliopsoas compartment lesions: a radiologic evaluation

    International Nuclear Information System (INIS)

    Leao, Alberto Ribeiro de Souza; Amaral, Raquel Portugal Guimaraes; Abud, Thiago Giansante; Demarchi, Guilherme Tadeu Sauaia; Freire Filho, Edison de Oliveira; Novack, Paulo Rogerio; Campos, Flavio do Amaral; Shigueoka, David Carlos; Fernandes, Artur da Rocha Correa; Szejnfeld, Jacob; D'Ippolito, Giuseppe

    2007-01-01

    The iliopsoas compartment, a posterior boundary of the retroperitoneum, is comprised of the psoas major, psoas minor and iliac muscles. The symptoms picture in patients presenting with pathological involvement of this compartment may show a wide range of nonspecific clinical presentations that may lead to delayed diagnosis. However, in the search of an etiological diagnosis, it is already known that inflammation, tumors, and hemorrhages account for almost all the lesions affecting the iliopsoas compartment. By means of a retrospective analysis of radiological studies in patients with iliopsoas compartment lesions whose diagnosis was confirmed by anatomopathological evaluation or clinical follow-up, we have reviewed its anatomy as well as the main forms of involvement, with the purpose of identifying radiological signs that may help to narrow down the potential differential diagnoses. As each lesion is approached we will discuss the main radiological findings such as presence of gas in pyogenic abscesses, bone destruction and other bone changes of vertebral bodies in lesions secondary to tuberculosis, involvement of fascial planes in cases of neoplasms, and differences in signal density and intensity of hematomas secondary to hemoglobin degradation, among others. So, we have tried to present cases depicting the most frequent lesions involving the iliopsoas compartment, with emphasis on those signs that can lead us to a more specific etiological diagnosis. (author)

  6. Iliopsoas compartment lesions: a radiologic evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Leao, Alberto Ribeiro de Souza; Amaral, Raquel Portugal Guimaraes; Abud, Thiago Giansante; Demarchi, Guilherme Tadeu Sauaia; Freire Filho, Edison de Oliveira; Novack, Paulo Rogerio; Campos, Flavio do Amaral; Shigueoka, David Carlos; Fernandes, Artur da Rocha Correa; Szejnfeld, Jacob; D' Ippolito, Giuseppe [Universidade Federal de Sao Paulo (UNIFESP-EPM), Sao Paulo, SP (Brazil). Dept. de Diagnostico por Imagem]. E-mail: ar.leao@uol.com.br; Santos, Jose Eduardo Mourao [Universidade Federal de Sao Paulo (UNIFESP-EPM), Sao Paulo, SP (Brazil)

    2007-07-15

    The iliopsoas compartment, a posterior boundary of the retroperitoneum, is comprised of the psoas major, psoas minor and iliac muscles. The symptoms picture in patients presenting with pathological involvement of this compartment may show a wide range of nonspecific clinical presentations that may lead to delayed diagnosis. However, in the search of an etiological diagnosis, it is already known that inflammation, tumors, and hemorrhages account for almost all the lesions affecting the iliopsoas compartment. By means of a retrospective analysis of radiological studies in patients with iliopsoas compartment lesions whose diagnosis was confirmed by anatomopathological evaluation or clinical follow-up, we have reviewed its anatomy as well as the main forms of involvement, with the purpose of identifying radiological signs that may help to narrow down the potential differential diagnoses. As each lesion is approached we will discuss the main radiological findings such as presence of gas in pyogenic abscesses, bone destruction and other bone changes of vertebral bodies in lesions secondary to tuberculosis, involvement of fascial planes in cases of neoplasms, and differences in signal density and intensity of hematomas secondary to hemoglobin degradation, among others. So, we have tried to present cases depicting the most frequent lesions involving the iliopsoas compartment, with emphasis on those signs that can lead us to a more specific etiological diagnosis. (author)

  7. Gaucher disease and comorbidities: B-cell malignancy and parkinsonism.

    Science.gov (United States)

    Cox, Timothy M; Rosenbloom, Barry E; Barker, Roger A

    2015-07-01

    Data emerging from the International Collaborative Gaucher Group (ICGG) Gaucher Registry together with other contemporary clinical surveys have revealed a close association between Gaucher disease and non-Hodgkin's B-cell lymphoma and myeloma and Gaucher disease and Parkinson's disease. Several possible explanations for increased B-cell proliferation and neoplasia in Gaucher disease have been proposed, including the possible influence of sphingosine (derived from the extra lysosomal metabolism of glucosylceramide), gene modifiers, splenectomy and immune system deregulation induced by cytokines, chemokines, and hydrolases released from Gaucher cells. Parkinson's disease is frequently seen in the otherwise-healthy relatives of Gaucher disease patients leading to the finding that GBA mutations represent a genetic risk factor for Parkinson's disease. The mechanism of the association between GBA mutations and Parkinson's disease has yet to be elucidated but the pathogenesis appears distinct from that of Gaucher disease. Several pathogenic pathways have been proposed including lysosomal and/or mitochondrial dysfunction. The effect of Gaucher disease specific therapies on the incidence of cancer or Parkinson's disease are not clear and will likely be evaluated in future ICGG Gaucher Registry studies. © 2015 Wiley Periodicals, Inc.

  8. Bcl-2 antisense therapy in B-cell malignancies.

    Science.gov (United States)

    Chanan-Khan, Asher

    2005-07-01

    Bcl-2 is an apoptosis regulating protein, overexpression of which is associated with chemotherapy resistant disease, aggressive clinical course, and poor survival in patients with B-cell lymphoproliferative disorders. Overexpression of Bcl-2 protein results in an aberrant intrinsic apoptotic pathway that confers a protective effect on malignant cells against a death signal (e.g., chemotherapy or radiotherapy). Downregulation of this oncoprotein, thus, represents a possible new way to target clinically aggressive disease. Preclinical studies have shown that this oncoprotein can be effectively decreased by Bcl-2 antisense in malignant lymphoid cells and can reverse chemotherapy resistance, as well as enhance the anti-apoptotic potential of both chemotherapeutic and biologic agents. Ongoing clinical trials are exploring the role of Bcl-2 downregulation with oblimersen (Bcl-2 antisense) in patients with non-Hodgkin's lymphoma, chronic lymphocytic leukemia and multiple myeloma. Early results from these studies are promising and support the proof of the principle. As these studies are completed and mature data emerges, the role of Bcl-2 antisense therapy in the treatment of B-cell malignancies will become clearer.

  9. Towards the generation of B-cell receptor retrogenic mice.

    Directory of Open Access Journals (Sweden)

    Jenny Freitag

    Full Text Available Transgenic expression of B- and T-cell receptors (BCRs and TCRs, respectively has been a standard tool to study lymphocyte development and function in vivo. The generation of transgenic mice is time-consuming and, therefore, a faster method to study the biology of defined lymphocyte receptors in vivo would be highly welcome. Using 2A peptide-linked multicistronic retroviral vectors to transduce stem cells, TCRs can be expressed rapidly in mice of any background. We aimed at adopting this retrogenic technology to the in vivo expression of BCRs. Using a well characterised BCR specific for hen egg lysozyme (HEL, we achieved surface expression of the retrogenically encoded BCR in a Rag-deficient pro B-cell line in vitro. In vivo, retrogenic BCRs were detectable only intracellularly but not on the surface of B cells from wild type or Rag2-deficient mice. This data, together with the fact that no BCR retrogenic mouse model has been published in the 7 years since the method was originally published for TCRs, strongly suggests that achieving BCR-expression in vivo with retrogenic technology is highly challenging if not impossible.

  10. Primary intravascular large B-cell lymphoma of pituitary

    Directory of Open Access Journals (Sweden)

    K R Anila

    2012-01-01

    Full Text Available A 68-year-old retired nurse, who was a known hypertensive on medication, presented with prolonged fever of 2-month duration without any clinical evidence of infection. On examination she had altered mental status. She also had other nonspecific complaints such as sleep disturbances, loss of weight, etc. On investigation, she was found to have anemia, thrombocytopenia, raised erythrocyte sedimentation rate (ESR, C-reactive protein (CRP, and lactate dehydrogenase (LDH values. She also had electrolyte imbalance. Radiological evaluation of brain showed mass lesion in the sella turcica, suggestive of pituitary adenoma. Biochemical evaluation showed hypopituitarism. Trans-sphenoidal biopsy was done. Based on histopathological and immunohistochemical findings a diagnosis of intravascular large B-cell lymphoma (IVLBCL of pituitary was made. Our patient′s condition deteriorated rapidly and she succumbed to her illness before therapy could be initiated. We are reporting this case because of the rare subtype of large B-cell lymphoma presenting at an extremely unusual primary site.

  11. Modulation of B-cell receptor and microenvironment signaling by a guanine exchange factor in B-cell malignancies

    International Nuclear Information System (INIS)

    Liao, Wei; Sharma, Sanjai

    2016-01-01

    Objective: Chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL) cells over-express a guanine exchange factor (GEF), Rasgrf-1. This GEF increases active Ras as it catalyzes the removal of GDP from Ras so that GTP can bind and activate Ras. This study aims to study the mechanism of action of Rasgrf-1 in B-cell malignancies. Methods: N-terminus truncated Rasgrf-1 variants have a higher GEF activity as compared to the full-length transcript therefore a MCL cell line with stable over-expression of truncated Rasgrf-1 was established. The B-cell receptor (BCR) and chemokine signaling pathways were compared in the Rasgrf-1 over-expressing and a control transfected cell line. Results: Cells over-expressing truncated form of Rasgrf-1 have a higher proliferative rate as compared to control transfected cells. BCR was activated by lower concentrations of anti-IgM antibody in Rasgrf-1 over-expressing cells as compared to control cells indicating that these cells are more sensitive to BCR signaling. BCR signaling also phosphorylates Rasgrf-1 that further increases its GEF function and amplifies BCR signaling. This activation of Rasgrf-1 in over-expressing cells resulted in a higher expression of phospho-ERK, AKT, BTK and PKC-alpha as compared to control cells. Besides BCR, Rasgrf-1 over-expressing cells were also more sensitive to microenvironment stimuli as determined by resistance to apoptosis, chemotaxis and ERK pathway activation. Conclusions: This GEF protein sensitizes B-cells to BCR and chemokine mediated signaling and also upregulates a number of other signaling pathways which promotes growth and survival of these cells

  12. Expression of the Grb2-related protein of the lymphoid system in B cell subsets enhances B cell antigen receptor signaling through mitogen-activated protein kinase pathways.

    Science.gov (United States)

    Yankee, Thomas M; Solow, Sasha A; Draves, Kevin D; Clark, Edward A

    2003-01-01

    Adapter proteins play a critical role in regulating signals triggered by Ag receptor cross-linking. These small molecules link receptor proximal events with downstream signaling pathways. In this study, we explore the expression and function of the Grb2-related protein of the lymphoid system (GrpL)/Grb2-related adaptor downstream of Shc adapter protein in human B cells. GrpL is expressed in naive B cells and is down-regulated following B cell Ag receptor ligation. By contrast, germinal center and memory B cells express little or no GrpL. Using human B cell lines, we detected constitutive interactions between GrpL and B cell linker protein, Src homology (SH)2 domain-containing leukocyte protein of 76 kDa, hemopoietic progenitor kinase 1, and c-Cbl. The N-terminal SH3 domain of GrpL binds c-Cbl while the C-terminal SH3 domain binds B cell linker protein and SH2 domain-containing leukocyte protein of 76 kDa. Exogenous expression of GrpL in a GrpL-negative B cell line leads to enhanced Ag receptor-induced extracellular signal-related kinase and p38 mitogen-activated protein kinase phosphorylation. Thus, GrpL expression in human B cell subsets appears to regulate Ag receptor-mediated signaling events.

  13. Dual-reactive B cells are autoreactive and highly enriched in the plasmablast and memory B cell subsets of autoimmune mice

    Science.gov (United States)

    Fournier, Emilie M.; Velez, Maria-Gabriela; Leahy, Katelyn; Swanson, Cristina L.; Rubtsov, Anatoly V.; Torres, Raul M.

    2012-01-01

    Rare dual-reactive B cells expressing two types of Ig light or heavy chains have been shown to participate in immune responses and differentiate into IgG+ cells in healthy mice. These cells are generated more often in autoreactive mice, leading us to hypothesize they might be relevant in autoimmunity. Using mice bearing Igk allotypic markers and a wild-type Ig repertoire, we demonstrate that the generation of dual-κ B cells increases with age and disease progression in autoimmune-prone MRL and MRL/lpr mice. These dual-reactive cells express markers of activation and are more frequently autoreactive than single-reactive B cells. Moreover, dual-κ B cells represent up to half of plasmablasts and memory B cells in autoimmune mice, whereas they remain infrequent in healthy mice. Differentiation of dual-κ B cells into plasmablasts is driven by MRL genes, whereas the maintenance of IgG+ cells is partly dependent on Fas inactivation. Furthermore, dual-κ B cells that differentiate into plasmablasts retain the capacity to secrete autoantibodies. Overall, our study indicates that dual-reactive B cells significantly contribute to the plasmablast and memory B cell populations of autoimmune-prone mice suggesting a role in autoimmunity. PMID:22927551

  14. B-cell subset alterations and correlated factors in HIV-1 infection.

    Science.gov (United States)

    Pensieroso, Simone; Galli, Laura; Nozza, Silvia; Ruffin, Nicolas; Castagna, Antonella; Tambussi, Giuseppe; Hejdeman, Bo; Misciagna, Donatella; Riva, Agostino; Malnati, Mauro; Chiodi, Francesca; Scarlatti, Gabriella

    2013-05-15

    During HIV-1 infection, the development, phenotype, and functionality of B cells are impaired. Transitional B cells and aberrant B-cell populations arise in blood, whereas a declined percentage of resting memory B cells is detected. Our study aimed at pinpointing the demographic, immunological, and viral factors driving these pathological findings, and the role of antiretroviral therapy in reverting these alterations. B-cell phenotype and correlating factors were evaluated. Variations in B-cell subsets were evaluated by flow cytometry in HIV-1-infected individuals naive to therapy, elite controllers, and patients treated with antiretroviral drugs (virological control or failure). Multivariable analysis was performed to identify variables independently associated with the B-cell alterations. Significant differences were observed among patients' groups in relation to all B-cell subsets. Resting memory B cells were preserved in patients naive to therapy and elite controllers, but reduced in treated patients. Individuals naive to therapy and experiencing multidrug failure, as well as elite controllers, had significantly higher levels of activated memory B cells compared to healthy controls. In the multivariate analysis, plasma viral load and nadir CD4 T cells independently correlated with major B-cell alterations. Coinfection with hepatitis C but not hepatitis B virus also showed an impact on specific B-cell subsets. Successful protracted antiretroviral treatment led to normalization of all B-cell subsets with exception of resting memory B cells. Our results indicate that viremia and nadir CD4 T cells are important prognostic markers of B-cell perturbations and provide evidence that resting memory B-cell depletion during chronic infection is not reverted upon successful antiretroviral therapy.

  15. Post-dialysis urea concentration: comparison between one- compartment model and two-compartment model

    International Nuclear Information System (INIS)

    Tamrin, N S Ahmad; Ibrahim, N

    2014-01-01

    The reduction of the urea concentration in blood can be numerically projected by using one-compartment model and two-compartment model with no variation in body fluid. This study aims to compare the simulated values of post-dialysis urea concentration for both models with the clinical data obtained from the hospital. The clinical assessment of adequacy of a treatment is based on the value of Kt/V. Further, direct calculation using clinical data and one-compartment model are presented in the form of ratio. It is found that the ratios of postdialysis urea concentration simulated using two-compartment model are higher compared to the ratios of post-dialysis urea concentration using one-compartment model. In addition, most values of post-dialysis urea concentration simulated using two-compartment model are much closer to the clinical data compared to values simulated using one-compartment model. Kt/V values calculated directly using clinical data are found to be higher than Kt/V values derived from one-compartment model

  16. Cigarette smoke-induced emphysema : A role for the B cell?

    NARCIS (Netherlands)

    van der Strate, BWA; Postma, DS; Brandsma, CA; Melgert, BN; Luinge, MA; Geerlings, M; Hylkema, MN; van den Berg, Anke; Timens, W; Kerstjens, HAM

    2006-01-01

    Rationale: Little is known about what drives the inflammatory reaction in the development of chronic obstructive lung disease. B cells have been found. Objective: To study the involvement of B cells in the development of emphysema. Methods: The presence of B-cell follicles and their interaction with

  17. Monovalent engagement of the BCR activates ovalbumin-specific transnuclear B cells

    NARCIS (Netherlands)

    Avalos, Ana M.; Bilate, Angelina M.; Witte, Martin D.; Tai, Albert K.; He, Jiang; Frushicheva, Maria P.; Thill, Peter D.; Meyer-Wentrup, Friederike; Theile, Christopher S.; Chakraborty, Arup K.; Zhuang, Xiaowei; Ploegh, Hidde L.

    2014-01-01

    Valency requirements for B cell activation upon antigen encounter are poorly understood. OB1 transnuclear B cells express an IgG1 B cell receptor (BCR) specific for ovalbumin (OVA), the epitope of which can be mimicked using short synthetic peptides to allow antigen-specific engagement of the BCR.

  18. Galectin-1 is required for the regulatory function of B cells.

    Science.gov (United States)

    Alhabbab, R; Blair, P; Smyth, L A; Ratnasothy, K; Peng, Q; Moreau, A; Lechler, R; Elgueta, R; Lombardi, G

    2018-02-09

    Galectin-1 (Gal-1) is required for the development of B cells in the bone marrow (BM), however very little is known about the contribution of Gal-1 to the development of B cell regulatory function. Here, we report an important role for Gal-1 in the induction of B cells regulatory function. Mice deficient of Gal-1 (Gal-1 -/- ) showed significant loss of Transitional-2 (T2) B cells, previously reported to include IL-10 + regulatory B cells. Gal-1 -/- B cells stimulated in vitro via CD40 molecules have impaired IL-10 and Tim-1 expression, the latter reported to be required for IL-10 production in regulatory B cells, and increased TNF-α expression compared to wild type (WT) B cells. Unlike their WT counterparts, T2 and T1 Gal-1 -/- B cells did not suppress TNF-α expression by CD4 + T cells activated in vitro with allogenic DCs (allo-DCs), nor were they suppressive in vivo, being unable to delay MHC-class I mismatched skin allograft rejection following adoptive transfer. Moreover, T cells stimulated with allo-DCs show an increase in their survival when co-cultured with Gal-1 -/- T2 and MZ B cells compared to WT T2 and MZ B cells. Collectively, these data suggest that Gal-1 contributes to the induction of B cells regulatory function.

  19. Transitional-2 B cells acquire regulatory function during tolerance induction and contribute to allograft survival.

    Science.gov (United States)

    Moreau, Aurélie; Blair, Paul A; Chai, Jian-Guo; Ratnasothy, Kulachelvy; Stolarczyk, Emilie; Alhabbab, Rowa; Rackham, Chloe L; Jones, Peter M; Smyth, Lesley; Elgueta, Raul; Howard, Jane K; Lechler, Robert I; Lombardi, Giovanna

    2015-03-01

    In humans, tolerance to renal transplants has been associated with alterations in B-cell gene transcription and maintenance of the numbers of circulating transitional B cells. Here, we use a mouse model of transplantation tolerance to investigate the contribution of B cells to allograft survival. We demonstrate that transfer of B cells from mice rendered tolerant to MHC class I mismatched skin grafts can prolong graft survival in a dose-dependent and antigen-specific manner to a degree similar to that afforded by graft-specific regulatory T (Treg) cells. Tolerance in this model was associated with an increase in transitional-2 (T2) B cells. Only T2 B cells from tolerized mice, not naïve T2 nor alloantigen experienced T2, were capable of prolonging skin allograft survival, and suppressing T-cell activation. Tolerized T2 B cells expressed lower levels of CD86, increased TIM-1, and demonstrated a preferential survival in vivo. Furthermore, we demonstrate a synergistic effect between tolerized B cells and graft-specific Treg cells. IL-10 production by T2 B cells did not contribute to tolerance, as shown by transfer of B cells from IL-10(-/-) mice. These results suggest that T2 B cells in tolerant patients may include a population of regulatory B cells that directly inhibit graft rejection. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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    Lifescience Database Archive (English)

    Full Text Available Oth.Bld.10.AllAg.Lymphoma,_B-Cell hg19 TFs and others Blood Lymphoma, B-Cell SRX092...416,SRX092414 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Oth.Bld.10.AllAg.Lymphoma,_B-Cell.bed ...

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    Lifescience Database Archive (English)

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  11. File list: His.Bld.20.AllAg.Lymphoma,_B-Cell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  12. File list: ALL.Bld.20.AllAg.Pro-B_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  13. File list: His.Bld.50.AllAg.Pro-B_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  14. File list: His.Bld.20.AllAg.Pro-B_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  15. [The perichromatin compartment of the cell nucleus].

    Science.gov (United States)

    Bogoliubov, D S

    2014-01-01

    In this review, the data on the structure and composition of the perichromatin compartment, a special border area between the condensed chromatin and the interchromatin space of the cell nucleus, are discussed in the light of the concept of nuclear functions in complex nuclear architectonics. Morphological features, molecular composition and functions of main extrachromosomal structures of the perichromatin compartment, perichromatin fibrils (PFs) and perichromatin granules (PGs) including nuclear stress-bodies (nSBs) that are derivates of the PGs under heat shock, are presented. A special attention was paid to the features of the molecular compositions of PFs and PGs in different cell types and at different physiological conditions.

  16. Effects of combustible stacking in large compartments

    DEFF Research Database (Denmark)

    Gentili, Filippo; Giuliani, Luisa; Bontempi, Franco

    2013-01-01

    This paper focuses on the modelling of fire in case of various distributions of combustible materials in a large compartment. Large compartments often represent a challenge for structural fire safety, because of lack of prescriptive rules to follow and difficulties of taking into account the effect...... of non uniform distribution of the combustible materials and fire propagation. These aspects are discussed in this paper with reference to an industrial steel building, taken as case study. Fires triggered by the burning of wooden pallets stored in the premises have been investigated with respect...

  17. Maternal and fetal mechanisms of B cell regulation during pregnancy: human Chorionic Gonadotropin stimulates B cells to produce IL-10 while alpha-fetoprotein drives them into apoptosis

    Directory of Open Access Journals (Sweden)

    Franziska Fettke

    2016-12-01

    Full Text Available Maternal immune tolerance towards the fetus is an essential requisite for pregnancy. While T cell functions are well documented, little is known about the participation of B cells. We have previously suggested that IL-10 producing B cells are involved in pregnancy tolerance in mice and humans. By employing murine and human systems, we report now that fetal trophoblasts positively regulate the generation of IL-10 producing B cells. We next studied the participation of hormones produced by the placenta as well as the fetal protein alpha-fetoprotein (AFP in B cell modulation. Human Chorionic Gonadotropin (hCG, but not progesterone, estrogen or a combination of both, was able to promote changes in B cell phenotype and boost their IL-10 production, which was abolished after blocking hCG. The hCG-induced B cell phenotype was not associated with augmented galactosylation, sialylation or fucosylation of IgG subclasses in their Fc. In vitro, hCG induced the synthesis of asymmetrically glycosylated antibodies in their Fab region. Interestingly, AFP had dual effects depending on the concentration. At concentrations corresponding to maternal serum levels, it did not modify the phenotype or IL-10 secretion of B cells. At fetal concentrations, however, AFP was able to drive B cells into apoptosis, which may indicate a protective mechanism to avoid maternal B cells to reach the fetus.Our data suggests that the fetus secrete factors that promote a pregnancy-friendly B cell phenotype, unraveling interesting aspects of B cell function and modulation by pregnancy hormones and fetal proteins.

  18. Proton pump inhibitors induce apoptosis of human B-cell tumors through a caspase-independent mechanism involving reactive oxygen species.

    Science.gov (United States)

    De Milito, Angelo; Iessi, Elisabetta; Logozzi, Mariantonia; Lozupone, Francesco; Spada, Massimo; Marino, Maria Lucia; Federici, Cristina; Perdicchio, Maurizio; Matarrese, Paola; Lugini, Luana; Nilsson, Anna; Fais, Stefano

    2007-06-01

    Proton pumps like the vacuolar-type H+ ATPase (V-ATPase) are involved in the control of cellular pH in normal and tumor cells. Treatment with proton pump inhibitors (PPI) induces sensitization of cancer cells to chemotherapeutics via modifications of cellular pH gradients. It is also known that low pH is the most suitable condition for a full PPI activation. Here, we tested whether PPI treatment in unbuffered culture conditions could affect survival and proliferation of human B-cell tumors. First, we showed that PPI treatment increased the sensitivity to vinblastine of a pre-B acute lymphoblastic leukemia (ALL) cell line. PPI, per se, induced a dose-dependent inhibition of proliferation of tumor B cells, which was associated with a dose- and time-dependent apoptotic-like cytotoxicity in B-cell lines and leukemic cells from patients with pre-B ALL. The effect of PPI was mediated by a very early production of reactive oxygen species (ROS), that preceded alkalinization of lysosomal pH, lysosomal membrane permeabilization, and cytosol acidification, suggesting an early destabilization of the acidic vesicular compartment. Lysosomal alterations were followed by mitochondrial membrane depolarization, release of cytochrome c, chromatin condensation, and caspase activation. However, inhibition of caspase activity did not affect PPI-induced cell death, whereas specific inhibition of ROS by an antioxidant (N-acetylcysteine) significantly delayed cell death and protected both lysosomal and mitochondrial membranes. The proapoptotic activity of PPI was consistent with a clear inhibition of tumor growth following PPI treatment of B-cell lymphoma in severe combined immunodeficient mice. This study further supports the importance of acidity and pH gradients in tumor cell homeostasis and suggests new therapeutic approaches for human B-cell tumors based on PPI.

  19. B cell receptor inhibition as a target for CLL therapy.

    Science.gov (United States)

    Jeyakumar, Deepa; O'Brien, Susan

    2016-03-01

    Inhibitors of the B cell receptor (BCR) represent an attractive therapeutic option for patients with chronic lymphocytic leukemia. Recently approved inhibitors of Bruton's tyrosine kinase (ibrutinib) and phosphatidylinositol 3-kinase (idelalisib), are promising agents because they are generally well tolerated and highly effective. These agents may be particularly important in the treatment of older patients who are less able to tolerate the myelosuppression (and infections) associated with chemoimmunotherapy. As a class of medications, BCR inhibitors have some unique side effects including redistribution lymphocytosis. Ibrutinib has specific toxicities including increased risk for bleeding and atrial fibrillation. Idelalisib also has some unique toxicities consisting of transaminitis, diarrhea and pneumonitis. Ongoing clinical trials are evaluating these agents in combination with antibodies, chemotherapy and other small molecules. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. T cell-B cell interactions in primary immunodeficiencies.

    Science.gov (United States)

    Tangye, Stuart G; Deenick, Elissa K; Palendira, Umaimainthan; Ma, Cindy S

    2012-02-01

    Regulated interactions between cells of the immune system facilitate the generation of successful immune responses, thereby enabling efficient neutralization and clearance of pathogens and the establishment of both cell- and humoral-mediated immunological memory. The corollary of this is that impediments to efficient cell-cell interactions, normally necessary for differentiation and effector functions of immune cells, underly the clinical features and disease pathogenesis of primary immunodeficiencies. In affected individuals, these defects manifest as impaired long-term humoral immunity and susceptibility to infection by specific pathogens. In this review, we discuss the importance of, and requirements for, effective interactions between B cells and T cells during the formation of CD4(+) T follicular helper cells and the elicitation of cytotoxic function of virus-specific CD8(+) T cells, as well as how these processes are abrogated in primary immunodeficiencies due to loss-of-function mutations in defined genes. © 2012 New York Academy of Sciences.

  1. [Primary cutaneous B-cell lymphomas: study of 22 cases].

    Science.gov (United States)

    Martín Carrasco, Pablo; Morillo Andújar, Mercedes; Pérez Ruiz, Carmen; de Zulueta Dorado, Teresa; Cabrera Pérez, Rocío; Conejo-Mir, Julián

    2016-09-02

    Primary cutaneous B-cell lymphoma (CBCL) is a very low prevalence neoplasm and constitutes 25% of all primary cutaneous lymphomas. Our objective was to discover the epidemiological, clinic and histologic characteristics of CBCL in our area. Retrospective descriptive study with patients with histologic diagnosis of CBCL followed up in our department between 2004 and 2015. Twenty-two patients with CBCL were included; 65% were men and 35% were women. Follicle centre lymphoma was the most common subtype (41%). Only 3 cases presented with node involvement and one with bone marrow invasion. Five recurrences were detected and one patient died because of the CBCL. This is one of the first CBCL series in theSpanish population. The incidence, sex, age, subtype distribution, clinical features and immunohistochemical patterns are very similar to those of the other series. Copyright © 2016 Elsevier España, S.L.U. All rights reserved.

  2. B Cell Depletion: Rituximab in Glomerular Disease and Transplantation

    Directory of Open Access Journals (Sweden)

    S. Marinaki

    2013-12-01

    Full Text Available B cells play a central role in the pathogenesis of many autoimmune diseases. Selective targeting can be achieved with the use of the monoclonal antibody rituximab. In addition to being a drug for non-Hodgkin's lymphoma, rituximab is also an FDA-approved treatment for refractory rheumatoid arthritis and, since recently, ANCA vasculitis. It has shown efficacy in many autoimmune diseases. This review will discuss current evidence and the rationale of the use of rituximab in glomerular diseases, including randomized controlled trials. The focus will be on the use of rituximab in idiopathic membranous nephropathy, systemic lupus erythematosus and ANCA-associated vasculitis. The emerging role of rituximab in renal transplantation, where it seems to be important for the desensitization protocols for highly sensitized patients as well as for the preconditioning of ABO-incompatible recipients and the treatment of antibody-mediated rejection, will also be addressed.

  3. Cerebral toxoplasmosis in a diffuse large B cell lymphoma patient

    International Nuclear Information System (INIS)

    Savsek, Lina; Opaskar, Tanja Ros

    2016-01-01

    Toxoplasmosis is an opportunistic protozoal infection that has, until now, probably been an underestimated cause of encephalitis in patients with hematological malignancies, independent of stem cell or bone marrow transplant. T and B cell depleting regimens are probably an important risk factor for reactivation of a latent toxoplasma infection in these patients. We describe a 62-year-old HIV-negative right-handed Caucasian female with systemic diffuse large B cell lymphoma who presented with sudden onset of high fever, headache, altered mental status, ataxia and findings of pancytopenia, a few days after receiving her final, 8 th cycle of rituximab, cyclophosphamide, vincristine, doxorubicin, prednisolone (R-CHOP) chemotherapy regimen. A progression of lymphoma to the central nervous system was suspected. MRI of the head revealed multiple on T2 and fluid attenuated inversion recovery (FLAIR) hyperintense parenchymal lesions with mild surrounding edema, located in both cerebral and cerebellar hemispheres that demonstrated moderate gadolinium enhancement. The polymerase chain reaction on cerebrospinal fluid (CSF PCR) was positive for Toxoplasma gondii. The patient was diagnosed with toxoplasmic encephalitis and successfully treated with sulfadiazine, pyrimethamine and folic acid. Due to the need for maintenance therapy with rituximab for lymphoma remission, the patient now continues with secondary prophylaxis of toxoplasmosis. With this case report, we wish to emphasize the need to consider cerebral toxoplasmosis in patients with hematological malignancies on immunosuppressive therapy when presenting with new neurologic deficits. In such patients, there are numerous differential diagnoses for cerebral toxoplasmosis, and the CNS lymphoma is the most difficult among all to distinguish it from. If left untreated, cerebral toxoplasmosis has a high mortality rate; therefore early recognition and treatment are of essential importance

  4. Circulating regulatory B cell subsets in patients with neuromyelitis optica spectrum disorders.

    Science.gov (United States)

    Han, Jinming; Sun, Li; Wang, Zhongkun; Fan, Xueli; Wang, Lifang; Song, Yang-Yang; Zhu, Jie; Jin, Tao

    2017-07-01

    This study analyzed the populations of three different subsets of regulatory B cells (Bregs) in the peripheral blood mononuclear cells (PBMCs) of patients with neuromyelitis optica spectrum disorders (NMOSDs) and explored the relationship between the changes in these subsets of Bregs and the severity of NMOSD. A total of 22 patients with relapsed NMOSDs before treatment were recruited in our study, along with 20 age and gender-matched healthy controls, from May 2015 to March 2016. The percentages and numbers for three different subsets of Bregs including the CD19 + CD24 hi CD38 hi , CD19 + CD24 hi CD27 + , and CD19 + CD5 + CD1d hi populations were evaluated in parallel by flow cytometry. Afterwards, correlations between the change of three different subsets of Bregs and disease severity were analyzed. We found significantly lower percentages of CD19 + CD24 hi CD38 hi and CD19 + CD5 + CD1d hi Bregs in NMOSDs patients than in healthy individuals. In contrast, the CD19 + CD24 hi CD27 + Bregs population was significantly higher in NMOSDs patients than in healthy individuals. However, the three different Bregs subsets showed no significant correlation with expanded disability status scale (EDSS) or annualized relapse rate (ARR). Our findings suggest that the subsets of Bregs may play complex roles in the pathogenesis of NMOSDs and are not correlated with clinical disease severity. Further insights into the potential role of subsets of Bregs could increase our basic knowledge of NMOSDs pathogenesis.

  5. A role for adhesion molecules in contact-dependent T help for B cells

    DEFF Research Database (Denmark)

    Owens, T

    1991-01-01

    The role of cell contact in T-dependent B cell activation was examined. Small resting B cells from C57BL/6 mice were cultured with CBA-derived, non-alloreactive cloned T helper cells in anti-T cell receptor V beta 8-coated microwells. This induced polyclonal B cell activation to enter cell cycle...... that continued cell contact involving adhesion/accessory molecules induces B cells to proliferate and to respond to T cell lymphokines. A signaling role for cell interaction molecules on B cells is proposed, similar to the role of these and analogous molecules on T cells....

  6. Local partial depletion of CD11b+ cells and their influence on choroidal neovascularization using the CD11b-HSVTK mouse model.

    Science.gov (United States)

    Brockmann, Claudia; Kociok, Norbert; Dege, Sabrina; Davids, Anja-Maria; Brockmann, Tobias; Miller, Kelly R; Joussen, Antonia M

    2018-03-14

    To assess the influence of retinal macrophages and microglia on the formation of choroidal neovascularization (CNV). Therefore, we used a transgenic mouse (CD11b-HSVTK) in which the application of ganciclovir (GCV) results in a depletion of CD11b + cells. We first investigated if a local depletion of CD11b + macrophages and microglia in the retina is feasible. In a second step, the influence of CD11b + cell depletion on CNV formation was analysed. One eye of each CD11b-HSVTK mouse was injected with GCV, and the fellow eye received sodium chloride solution (NaCl). Cell counting was performed at day 3 and 7 (one injection) or at day 14 and 21 (two injections). Choroidal neovascularization (CNV) was induced by argon laser and analysed at day 14. The most effective CD11b + cell depletion was achieved 7 days after a single injection and 14 days after two injections of GCV. After two injections of GCV, we found a significant reduction of CD11b + cells in central (52 ± 23.9 cells/mm 2 ) and peripheral retina (53 ± 20.6 cells/mm 2 ); compared to eyes received NaCl (216 ± 49.0 and 210 ± 50.5 cells/mm 2 , p depletion of CD11b + cells in the retina. Nevertheless, only a partial depletion of CD11b + cells could be achieved compared to baseline data without any intravitreal injections. Our results did not reveal a significant reduction in CNV areas. In the light of previous knowledge, the potential influence of systemic immune cells on CNV formation might be more relevant than expected. © 2018 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  7. Human Infant Memory B Cell and CD4+ T Cell Responses to HibMenCY-TT Glyco-Conjugate Vaccine.

    Directory of Open Access Journals (Sweden)

    Angela Fuery

    Full Text Available Carrier-specific T cell and polysaccharide-specific B cell memory responses are not well characterised in infants following glyco-conjugate vaccination. We aimed to determine if the number of Meningococcal (Men C- and Y- specific memory B cells and; number and quality of Tetanus Toxoid (TT carrier-specific memory CD4+ T cells are associated with polysaccharide-specific IgG post HibMenCY-TT vaccination. Healthy infants received HibMenCY-TT vaccine at 2, 4 and 6 months with a booster at 12 months. Peripheral blood mononuclear cells were isolated and polysaccharide-specific memory B cells enumerated using ELISpot. TT-specific memory CD4+ T cells were detected and phenotyped based on CD154 expression and intracellular TNF-α, IL-2 and IFN-γ expression following stimulation. Functional polysaccharide-specific IgG titres were measured using the serum bactericidal activity (SBA assay. Polysaccharide-specific Men C- but not Men Y- specific memory B cell frequencies pre-boost (12 months were significantly associated with post-boost (13 months SBA titres. Regression analysis showed no association between memory B cell frequencies post-priming (at 6 or 7 months and SBA at 12 months or 13 months. TT-specific CD4+ T cells were detected at frequencies between 0.001 and 0.112 as a percentage of CD3+ T cells, but their numbers were not associated with SBA titres. There were significant negative associations between SBA titres at M13 and cytokine expression at M7 and M12.Induction of persistent polysaccharide-specific memory B cells prior to boosting is an important determinant of secondary IgG responses in infants. However, polysaccharide-specific functional IgG responses appear to be independent of the number and quality of circulating carrier-specific CD4+ T cells after priming.

  8. B-cell exposure to self-antigen induces IL-10 producing B cells as well as IL-6- and TNF-α-producing B-cell subsets in healthy humans

    DEFF Research Database (Denmark)

    Langkjær, Anina; Kristensen, Birte; Hansen, Bjarke E

    2012-01-01

    Human B cells are able to secrete IL-10 after stimulation with mitogens, but their ability to produce IL-10 and regulate T-cell responses after stimulation with self-antigens is unclear. We co-cultured thyroglobulin-pulsed B cells from healthy donors with autologous T cells and observed production...... of IL-10 and TGF-β, in addition to TNF-α and IL-6. Pulsing with foreign antigen, tetanus toxoid (TT), induced a Th1-response with minimal IL-10 production. After thyroglobulin-pulsing, 1.10±0.50% of B cells and 1.00±0.20% of CD4(+) T cells produced IL-10, compared to 0.29±0.19% of B cells (P=0.01) and 0.......13±0.15% of CD4(+) T cells (P=0.006) following TT-pulsing. Thyroglobulin-stimulated, IL-10-secreting B cells were enriched within CD5(+) and CD24(high) cells. While thyroglobulin-pulsed B cells induced only modest proliferation of CD4(+) T cells, B cells pulsed with TT induced vigorous proliferation. Thus, B...

  9. Loss of PRDM1/BLIMP-1 function contributes to poor prognosis of activated B-cell-like diffuse large B-cell lymphoma

    DEFF Research Database (Denmark)

    Xia, Yi; Xu-Monette, Z Y; Tzankov, A

    2017-01-01

    PRDM1/BLIMP-1, a master regulator of plasma-cell differentiation, is frequently inactivated in activated B-cell-like (ABC) diffuse large B-cell lymphoma (DLBCL) patients. Little is known about its genetic aberrations and relevant clinical implications. A large series of patients with de novo DLBC...

  10. EBI2 overexpression in mice leads to B1 B-cell expansion and chronic lymphocytic leukemia-like B-cell malignancies.

    Science.gov (United States)

    Niss Arfelt, Kristine; Barington, Line; Benned-Jensen, Tau; Kubale, Valentina; Kovalchuk, Alexander L; Daugvilaite, Viktorija; Christensen, Jan Pravsgaard; Thomsen, Allan Randrup; Egerod, Kristoffer L; Bassi, Maria R; Spiess, Katja; Schwartz, Thue W; Wang, Hongsheng; Morse, Herbert C; Holst, Peter J; Rosenkilde, Mette M

    2017-02-16

    Human and mouse chronic lymphocytic leukemia (CLL) develops from CD5 + B cells that in mice and macaques are known to define the distinct B1a B-cell lineage. B1a cells are characterized by lack of germinal center (GC) development, and the B1a cell population is increased in mice with reduced GC formation. As a major mediator of follicular B-cell migration, the G protein-coupled receptor Epstein-Barr virus-induced gene 2 ( EBI2 or GPR183 ) directs B-cell migration in the lymphoid follicles in response to its endogenous ligands, oxysterols. Thus, upregulation of EBI2 drives the B cells toward the extrafollicular area, whereas downregulation is essential for GC formation. We therefore speculated whether increased expression of EBI2 would lead to an expanded B1 cell subset and, ultimately, progression to CLL. Here, we demonstrate that B-cell-targeted expression of human EBI2 (hEBI2) in mice reduces GC-dependent immune responses, reduces total immunoglobulin M (IgM) and IgG levels, and leads to increased proliferation and upregulation of cellular oncogenes. Furthermore, hEBI2 overexpression leads to an abnormally expanded CD5 + B1a B-cell subset (present as early as 4 days after birth), late-onset lymphoid cancer development, and premature death. These findings are highly similar to those observed in CLL patients and identify EBI2 as a promoter of B-cell malignancies.

  11. Genetic modification of human B-cell development: B-cell development is inhibited by the dominant negative helix loop helix factor Id3

    NARCIS (Netherlands)

    Jaleco, A. C.; Stegmann, A. P.; Heemskerk, M. H.; Couwenberg, F.; Bakker, A. Q.; Weijer, K.; Spits, H.

    1999-01-01

    Transgenic and gene targeted mice have contributed greatly to our understanding of the mechanisms underlying B-cell development. We describe here a model system that allows us to apply molecular genetic techniques to the analysis of human B-cell development. We constructed a retroviral vector with a

  12. The progeny of a single virgin B cell predominates the human recall B cell response to the capsular polysaccharide of Haemophilus influenzae type b

    DEFF Research Database (Denmark)

    Barington, T; Hougs, L; Juul, L

    1996-01-01

    of the cells originated from a common virgin B cell. Kinetic considerations implied that an extremely selected population of hypermutated memory B cells must have existed in these individuals before the first systemic immunization with the Ag. A possible role for the mucosal immune system in the priming...

  13. Low GILT expression is associated with poor patient survival in diffuse large B-cell lymphoma

    Directory of Open Access Journals (Sweden)

    Hannah ePhipps-Yonas

    2013-12-01

    Full Text Available The MHC class II-restricted antigen processing pathway presents antigenic peptides acquired in the endocytic route for the activation of CD4+ T cells. Multiple cancers express MHC class II, which may influence the anti-tumor immune response and patient outcome. Low MHC class II expression is associated with poor survival in diffuse large B-cell lymphoma (DLBCL, the most common form of aggressive non-Hodgkin lymphoma. Therefore, we investigated whether gamma-interferon-inducible lysosomal thiol reductase (GILT, an upstream component of the MHC class II-restricted antigen processing pathway that is not regulated by the transcription factor class II transactivator, may be important in DLBCL biology. GILT reduces protein disulfide bonds in the endocytic compartment, exposing additional epitopes for MHC class II binding and facilitating antigen presentation. In each of four independent gene expression profiling cohorts with a total of 585 DLBCL patients, low GILT expression was significantly associated with poor overall survival. In contrast, low expression of a classical MHC class II gene, HLA-DRA, was associated with poor survival in one of four cohorts. The association of low GILT expression with poor survival was independent of established clinical and molecular prognostic factors, the International Prognostic Index and the cell of origin classification, respectively. Immunohistochemical analysis of GILT expression in 96 DLBCL cases demonstrated variation in GILT protein expression within tumor cells which correlated strongly with GILT mRNA expression. These studies identify a novel association between GILT expression and clinical outcome in lymphoma. Our findings underscore the role of antigen processing in DLBCL and suggest that molecules targeting this pathway warrant investigation as potential therapeutics.

  14. B cell sub-types following acute malaria and associations with clinical immunity.

    Science.gov (United States)

    Sullivan, Richard T; Ssewanyana, Isaac; Wamala, Samuel; Nankya, Felistas; Jagannathan, Prasanna; Tappero, Jordan W; Mayanja-Kizza, Harriet; Muhindo, Mary K; Arinaitwe, Emmanuel; Kamya, Moses; Dorsey, Grant; Feeney, Margaret E; Riley, Eleanor M; Drakeley, Chris J; Greenhouse, Bryan; Sullivan, Richard

    2016-03-03

    Repeated exposure to Plasmodium falciparum is associated with perturbations in B cell sub-set homeostasis, including expansion atypical memory B cells. However, B cell perturbations immediately following acute malaria infection have been poorly characterized, especially with regard to their relationship with immunity to malaria. To better understand the kinetics of B cell sub-sets following malaria, the proportions of six B cell sub-sets were assessed at five time points following acute malaria in four to 5 years old children living in a high transmission region of Uganda. B cell sub-set kinetics were compared with measures of clinical immunity to malaria-lower parasite density at the time of malaria diagnosis and recent asymptomatic parasitaemia. Atypical memory B cell and transitional B cell proportions increased following malaria. In contrast, plasmablast proportions were highest at the time of malaria diagnosis and rapidly declined following treatment. Increased proportions of atypical memory B cells were associated with greater immunity to malaria, whereas increased proportions of transitional B cells were associated with evidence of less immunity to malaria. These findings highlight the dynamic changes in multiple B cell sub-sets following acute, uncomplicated malaria, and how these sub-sets are associated with developing immunity to malaria.

  15. B Cells Promote Th1- Skewed NKT Cell Response by CD1d-TCR Interaction.

    Science.gov (United States)

    Shin, Jung Hoon; Park, Se-Ho

    2013-10-01

    CD1d expressing dendritic cells (DCs) are good glyco-lipid antigen presenting cells for NKT cells. However, resting B cells are very weak stimulators for NKT cells. Although α-galactosylceramide (α-GalCer) loaded B cells can activate NKT cells, it is not well defined whether B cells interfere NKT cell stimulating activity of DCs. Unexpectedly, we found in this study that B cells can promote Th1-skewed NKT cell response, which means a increased level of IFN-γ by NKT cells, concomitant with a decreased level of IL-4, in the circumstance of co-culture of DCs and B Cells. Remarkably, the response promoted by B cells was dependent on CD1d expression of B cells.

  16. B cells exposed to enterobacterial components suppress development of experimental colitis

    DEFF Research Database (Denmark)

    Schmidt, Esben Gjerløff Wedebye; Larsen, Hjalte List; Kristensen, Nanna Ny

    2012-01-01

    ). RESULTS: We demonstrate that splenic B cells exposed to ebx produce large amounts of IL-10 in vitro and express CD1d and CD5 previously known to be associated with regulatory B cells. In SCID mice transplanted with colitogenic CD4(+) CD25(-) T cells, co-transfer of ebx-B cells significantly suppressed...... development of colitis. Suppression was dependent on B cell-derived IL-10, as co-transfer of IL-10 knockout ebx-B cells failed to suppress colitis. Ebx-B cell-mediated suppression of colitis was associated with a decrease in interferon gamma (IFN-¿)-producing T(H) 1 cells and increased frequencies of Foxp3......-expressing T cells. CONCLUSIONS: These data demonstrate that splenic B cells exposed to enterobacterial components acquire immunosuppressive functions by which they can suppress development of experimental T cell-mediated colitis in an IL-10-dependent way. (Inflamm Bowel Dis 2011;)....

  17. CEACAM1 induces B-cell survival and is essential for protective antiviral antibody production

    Science.gov (United States)

    Khairnar, Vishal; Duhan, Vikas; Maney, Sathish Kumar; Honke, Nadine; Shaabani, Namir; Pandyra, Aleksandra A.; Seifert, Marc; Pozdeev, Vitaly; Xu, Haifeng C.; Sharma, Piyush; Baldin, Fabian; Marquardsen, Florian; Merches, Katja; Lang, Elisabeth; Kirschning, Carsten; Westendorf, Astrid M.; Häussinger, Dieter; Lang, Florian; Dittmer, Ulf; Küppers, Ralf; Recher, Mike; Hardt, Cornelia; Scheffrahn, Inka; Beauchemin, Nicole; Göthert, Joachim R.; Singer, Bernhard B.; Lang, Philipp A.; Lang, Karl S.

    2015-01-01

    B cells are essential for antiviral immune defence because they produce neutralizing antibodies, present antigen and maintain the lymphoid architecture. Here we show that intrinsic signalling of CEACAM1 is essential for generating efficient B-cell responses. Although CEACAM1 exerts limited influence on the proliferation of B cells, expression of CEACAM1 induces survival of proliferating B cells via the BTK/Syk/NF-κB-axis. The absence of this signalling cascade in naive Ceacam1−/− mice limits the survival of B cells. During systemic infection with cytopathic vesicular stomatitis virus, Ceacam1−/− mice can barely induce neutralizing antibody responses and die early after infection. We find, therefore, that CEACAM1 is a crucial regulator of B-cell survival, influencing B-cell numbers and protective antiviral antibody responses. PMID:25692415

  18. B-Cell Dysregulation in Crohn's Disease Is Partially Restored with Infliximab Therapy.

    Directory of Open Access Journals (Sweden)

    Wilhelmina M C Timmermans

    Full Text Available B-cell depletion can improve a variety of chronic inflammatory diseases, but does not appear beneficial for patients with Crohn's disease.To elucidate the involvement of B cells in Crohn's disease, we here performed an 'in depth' analysis of intestinal and blood B-cells in this chronic inflammatory disease.Patients with Crohn's disease were recruited to study B-cell infiltrates in intestinal biopsies (n = 5, serum immunoglobulin levels and the phenotype and molecular characteristics of blood B-cell subsets (n = 21. The effects of infliximab treatment were studied in 9 patients.Granulomatous tissue showed infiltrates of B lymphocytes rather than Ig-secreting plasma cells. Circulating transitional B cells and CD21low B cells were elevated. IgM memory B cells were reduced and natural effector cells showed decreased replication histories and somatic hypermutation (SHM levels. In contrast, IgG and IgA memory B cells were normally present and their Ig gene transcripts carried increased SHM levels. The numbers of transitional and natural effector cells were normal in patients who responded clinically well to infliximab.B cells in patients with Crohn's disease showed signs of chronic stimulation with localization to granulomatous tissue and increased molecular maturation of IgA and IgG. Therapy with TNFα-blockers restored the defect in IgM memory B-cell generation and normalized transitional B-cell levels, making these subsets candidate markers for treatment monitoring. Together, these results suggest a chronic, aberrant B-cell response in patients with Crohn's disease, which could be targeted with new therapeutics that specifically regulate B-cell function.

  19. B cell follicle-like structures in multiple sclerosis-with focus on the role of B cell activating factor

    DEFF Research Database (Denmark)

    Morten, Haugen; Frederiksen, Jette L; Vinter, Matilda Degn

    2014-01-01

    B lymphocytes play an important role in the pathogenesis of multiple sclerosis (MS). Follicle-like structures (FLS) have recently been found in the subarachnoid space in the leptomeninges in some patients with secondary progressive MS (SPMS). They contain proliferating B lymphocytes, plasma cells......, helper T lymphocytes and a network of follicular dendritic cells. FLS have been shown to correlate with increased cortical demyelination, neuronal loss, meningeal infiltration and central nervous system inflammation, as well as lower age at disease onset and progression to severe disability and death....... In this review, we will discuss the role of FLS in MS pathogenesis and disease course and the possible influence by B cell activating factor (BAFF) and C-X-C motif chemokine 13 (CXCL13)....

  20. Increased frequency of circulating CD19+CD24hiCD38hi B cells with regulatory capacity in patients with Ankylosing spondylitis (AS naïve for biological agents.

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    María-Belén Bautista-Caro

    Full Text Available Our objective was to study the frequency of circulating CD19+CD24hiCD38hi B cells (Breg in AS patients. To this end, peripheral blood was drawn from AS patients naïve for TNF blockers (AS/nb (n = 42 and healthy controls (HC (n = 42. Six patients donated blood for a second time, 6 months after initiating treatment with anti-TNFα drugs. After isolation by Ficoll-Hypaque, PBMCs were stained with antibodies to CD3, CD4, CD19, CD24, and CD38, and examined by cytometry. For functional studies, total CD19+ B cells were isolated from PBMCs of 3 HC by magnetical sorting. Breg-depleted CD19+ B cells were obtained after CD19+CD24hiCD38hi B cells were removed from total CD19+ cells by cytometry. Total CD19+ B cells or Breg-depleted CD19+ B cells were established in culture and stimulated through their BCR. Secretion of IFNγ was determined by ELISA in culture supernatants. When compared with HC, AS/nb patients demonstrated a significantly increased frequency of Breg cells, which was independent of disease activity. Anti-TNFα drugs induced a significant reduction of circulating Breg numbers, which were no longer elevated after six months of treatment. Functional in vitro studies showed that the secretion of IFNγ was significantly higher in Breg-depleted as compared with total CD19+ B cells, indicating that Breg can downmodulate B cell pro-inflammatory cytokine secretion. In summary, an increased frequency of circulating CD19+CD24hiCD38hi B cells is observed in AS/nb patients, that is not related with disease activity; anti-TNFα drugs are able to downmodulate circulating Breg numbers in AS.

  1. Leg 201Tl-SPECT in chronic exertional compartment syndrome

    International Nuclear Information System (INIS)

    Elkadri, N.; Slim, I.; Blondet, C.; Choquet, Ph.; Constantinesco, A.; Lecocq, J.

    2004-01-01

    Leg 201 Tl-SPECT in chronic exertional compartment syndrome Background: The chronic exertional compartment syndrome is one of the most frequent origins regarding leg pain due to sport training. The diagnosis can be established by invasive compartment pressure measurement. The aim of this study is to evaluate the role that could have 201 Tl-SPECT for patients with suspicion of compartment syndrome. Patients and methods: 51 leg 201 Tl-SPECT exams were performed (exercise - and rest without reinjection) in 49 patients; 28 had compartment syndrome confirmed by pressure measurement. About 100 MBq of 201 Tl were injected during exercise, when pain appeared or at least after 25 minutes exercise. We studied mean percentages of level uptake for each compartment, referred to the maximal uptake of both legs. Results: 47 compartments were concerned by compartment syndrome and 361 compartments were not. Scintigraphic patterns in compartments are reversible ischaemia (45%), uptake stability (36%) or reverse redistribution (19%); these patterns are not linked to compartment syndrome. However, there is a significant difference of rest 201 Tl level uptake between compartments with and without compartment syndrome and a significant correlation between muscular pressure measurement and rest level uptake. Conclusion: 201 Tl-SPECT shows that only ischaemia does not explain compartment syndrome. Moreover, it allows to predict pressure variation during exercise but it does not offer any interest in order to select patients for muscular invasive pressure measurement. (author)

  2. Herpes simplex virus replication compartments can form by coalescence of smaller compartments

    International Nuclear Information System (INIS)

    Taylor, Travis J; McNamee, Elizabeth E.; Day, Cheryl; Knipe, David M.

    2003-01-01

    Herpes simplex virus (HSV) uses intranuclear compartmentalization to concentrate the viral and cellular factors required for the progression of the viral life cycle. Processes as varied as viral DNA replication, late gene expression, and capsid assembly take place within discrete structures within the nucleus called replication compartments. Replication compartments are hypothesized to mature from a few distinct structures, called prereplicative sites, that form adjacent to cellular nuclear matrix-associated ND10 sites. During productive infection, the HSV single-stranded DNA-binding protein ICP8 localizes to replication compartments. To further the understanding of replication compartment maturation, we have constructed and characterized a recombinant HSV-1 strain that expresses an ICP8 molecule with green fluorescent protein (GFP) fused to its C terminus. In transfected Vero cells that were infected with HSV, the ICP8-GFP protein localized to prereplicative sites in the presence of the viral DNA synthesis inhibitor phosphonoacetic acid (PAA) or to replication compartments in the absence of PAA. A recombinant HSV-1 strain expressing the ICP8-GFP virus replicated in Vero cells, but the yield was increased by 150-fold in an ICP8-complementing cell line. Using the ICP8-GFP protein as a marker for replication compartments, we show here that these structures start as punctate structures early in infection and grow into large, globular structures that eventually fill the nucleus. Large replication compartments were formed by small structures that either moved through the nucleus to merge with adjacent compartments or remained relatively stationary within the nucleus and grew by accretion and fused with neighboring structures

  3. SAP modulates B cell functions in a genetic background-dependent manner.

    Science.gov (United States)

    Detre, Cynthia; Yigit, Burcu; Keszei, Marton; Castro, Wilson; Magelky, Erica M; Terhorst, Cox

    2013-06-01

    Mutations affecting the SLAM-associated protein (SAP) are responsible for the X-linked lympho-proliferative syndrome (XLP), a severe primary immunodeficiency syndrome with disease manifestations that include fatal mononucleosis, B cell lymphoma and dysgammaglobulinemia. It is well accepted that insufficient help by SAP-/- CD4+ T cells, in particular during the germinal center reaction, is a component of dysgammaglobulinemia in XLP patients and SAP-/- animals. It is however not well understood whether in XLP patients and SAP-/- mice B cell functions are affected, even though B cells themselves do not express SAP. Here we report that B cell intrinsic responses to haptenated protein antigens are impaired in SAP-/- mice and in Rag-/- mice into which B cells derived from SAP-/- mice together with wt CD4+ T cells had been transferred. This impaired B cells functions are in part depending on the genetic background of the SAP-/- mouse, which affects B cell homeostasis. Surprisingly, stimulation with an agonistic anti-CD40 causes strong in vivo and in vitro B cell responses in SAP-/- mice. Taken together, the data demonstrate that genetic factors play an important role in the SAP-related B cell functions. The finding that anti-CD40 can in part restore impaired B cell responses in SAP-/- mice, suggests potentially novel therapeutic interventions in subsets of XLP patients. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. IL-4Rα-associated antigen processing by B cells promotes immunity in Nippostrongylus brasiliensis infection.

    Directory of Open Access Journals (Sweden)

    William G C Horsnell

    2013-10-01

    Full Text Available In this study, B cell function in protective T(H2 immunity against N. brasiliensis infection was investigated. Protection against secondary infection depended on IL-4Rα and IL-13; but not IL-4. Protection did not associate with parasite specific antibody responses. Re-infection of B cell-specific IL-4Rα⁻/⁻ mice resulted in increased worm burdens compared to control mice, despite their equivalent capacity to control primary infection. Impaired protection correlated with reduced lymphocyte IL-13 production and B cell MHC class II and CD86 surface expression. Adoptive transfer of in vivo N. brasiliensis primed IL-4Rα expressing B cells into naïve BALB/c mice, but not IL-4Rα or IL-13 deficient B cells, conferred protection against primary N. brasiliensis infection. This protection required MHC class II compatibility on B cells suggesting cognate interactions by B cells with CD4⁺ T cells were important to co-ordinate immunity. Furthermore, the rapid nature of these protective effects by B cells suggested non-BCR mediated mechanisms, such as via Toll Like Receptors, was involved, and this was supported by transfer experiments using antigen pulsed Myd88⁻/⁻ B cells. These data suggest TLR dependent antigen processing by IL-4Rα-responsive B cells producing IL-13 contribute significantly to CD4⁺ T cell-mediated protective immunity against N. brasiliensis infection.

  5. Selective induction of DNA repair pathways in human B cells activated by CD4+ T cells.

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    Xiaosheng Wu

    Full Text Available Greater than 75% of all hematologic malignancies derive from germinal center (GC or post-GC B cells, suggesting that the GC reaction predisposes B cells to tumorigenesis. Because GC B cells acquire expression of the highly mutagenic enzyme activation-induced cytidine deaminase (AID, GC B cells may require additional DNA repair capacity. The goal of this study was to investigate whether normal human B cells acquire enhanced expression of DNA repair factors upon AID induction. We first demonstrated that several DNA mismatch repair, homologous recombination, base excision repair, and ATR signaling genes were overexpressed in GC B cells relative to naïve and memory B cells, reflecting activation of a process we have termed somatic hyperrepair (SHR. Using an in vitro system, we next characterized activation signals required to induce AID expression and SHR. Although AID expression was induced by a variety of polyclonal activators, SHR induction strictly required signals provided by contact with activated CD4+ T cells, and B cells activated in this manner displayed reduced levels of DNA damage-induced apoptosis. We further show the induction of SHR is independent of AID expression, as GC B cells from AID-/-mice retained heightened expression of SHR proteins. In consideration of the critical role that CD4+ T cells play in inducing the SHR process, our data suggest a novel role for CD4+ T cells in the tumor suppression of GC/post-GC B cells.

  6. A two-scale model for correlation between B cell VDJ usage in zebrafish

    Science.gov (United States)

    Pan, Keyao; Deem, Michael

    2011-03-01

    The zebrafish (Danio rerio) is one of the model animals for study of immunology. The dynamics of the adaptive immune system in zebrafish is similar to that in higher animals. In this work, we built a two-scale model to simulate the dynamics of B cells in primary and secondary immune reactions in zebrafish and to explain the reported correlation between VDJ usage of B cell repertoires in distinct zebrafish. The first scale of the model consists of a generalized NK model to simulate the B cell maturation process in the 10-day primary immune response. The second scale uses a delay ordinary differential equation system to model the immune responses in the 6-month lifespan of zebrafish. The generalized NK model shows that mature B cells specific to one antigen mostly possess a single VDJ recombination. The probability that mature B cells in two zebrafish have the same VDJ recombination increases with the B cell population size or the B cell selection intensity and decreases with the B cell hypermutation rate. The ODE model shows a distribution of correlation in the VDJ usage of the B cell repertoires in two six-month-old zebrafish that is highly similar to that from experiment. This work presents a simple theory to explain the experimentally observed correlation in VDJ usage of distinct zebrafish B cell repertoires after an immune response.

  7. CD19 CAR-targeted T cells induce long-term remission and B Cell Aplasia in an immunocompetent mouse model of B cell acute lymphoblastic leukemia.

    Directory of Open Access Journals (Sweden)

    Marco L Davila

    Full Text Available Although many adults with B cell acute lymphoblastic leukemia (B-ALL are induced into remission, most will relapse, underscoring the dire need for novel therapies for this disease. We developed murine CD19-specific chimeric antigen receptors (CARs and an immunocompetent mouse model of B-ALL that recapitulates the disease at genetic, cellular, and pathologic levels. Mouse T cells transduced with an all-murine CD3ζ/CD28-based CAR that is equivalent to the one being used in our clinical trials, eradicate B-ALL in mice and mediate long-term B cell aplasias. In this model, we find that increasing conditioning chemotherapy increases tumor eradication, B cell aplasia, and CAR-modified T cell persistence. Quantification of recipient B lineage cells allowed us to estimate an in vivo effector to endogenous target ratio for B cell aplasia maintenance. In mice exhibiting a dramatic B cell reduction we identified a small population of progenitor B cells in the bone marrow that may serve as a reservoir for long-term CAR-modified T cell stimulation. Lastly, we determine that infusion of CD8+ CAR-modified T cells alone is sufficient to maintain long-term B cell eradication. The mouse model we report here should prove valuable for investigating CAR-based and other therapies for adult B-ALL.

  8. Similar disturbances in B cell activity and regulatory T cell function in Henoch-Schonlein purpura and systemic lupus erythematosus

    International Nuclear Information System (INIS)

    Beale, M.G.; Nash, G.S.; Bertovich, M.J.; MacDermott, R.P.

    1982-01-01

    The immunoglobulin synthesizing activities of peripheral mononuclear cells (MNC) from five patients with Henoch-Schonlein purpura (HSP) and eight patients with active systemic lupus erythematosus (SLE) were compared. Cumulative amounts of IgM, IgG, and IgA synthesized and secreted by unstimulated and PWM-stimulated patient cells over a 12-day period were determied in a solid-phase radioimmunoassay. In unstimulated control cultures mean rates of IgM, IgG, and IgA synthesis were less than 250 ng/ml. The synthetic activities of patient MNC were markedly increased. In HSP cultures IgA was the major immunoglobulin class produced (2810 x/divide 1.33 ng/ml) followed by IgG (1754 x/divide 1.32 ng/ml) and IgM (404 x/divide 1.16 ng/ml). In SLE cultures IgA and IgG syntheses were equally elevated (4427 x/divide 1.20 and 4438 x/divide 1.49 ng/ml, respectively) whereas IgM synthesis averaged 967 x/divide 1.66 ng/ml. PWM stimulation of pateient MNC caused a sharp decline in the synthesis of all three immunoglobulin classes. After T cell depletion B cell-enriched fractions from HSP and SLE patients maintained high levels of IgA and IgG synthesis that were inhibited by PWM and by normal allogeneic but not autologous T cells. In PWM-stimulted co-cultures, patient T cells nonspecifically suppressed the synthetic activities of autologous and control B cells. in contrast patient B cells achieved normal levels of immunoglobulin synthesis when cultured with control T cells plus PWM. In longitudinal studies patient B and T cell disturbances persisted despite clinical improvement

  9. Decreased neutrophil-associated miRNA and increased B-cell associated miRNA expression during tuberculosis.

    Science.gov (United States)

    van Rensburg, I C; du Toit, L; Walzl, G; du Plessis, N; Loxton, A G

    2018-05-20

    MicroRNAs are short non-coding RNAs that regulate gene expression by binding to, and suppressing the expression of genes. Research show that microRNAs have potential to be used as biomarkers for diagnosis, treatment response and can be used for therapeutic interventions. Furthermore, microRNA expression has effects on immune cell functions, which may lead to disease. Considering the important protective role of neutrophils and B-cells during M.tb infection, we evaluated the expression of microRNAs, known to alter function of these cells, in the context of human TB. We utilised real-time PCR to evaluate the levels of microRNA transcripts in the peripheral blood of TB cases and healthy controls. We found that neutrophil-associated miR-197-3p, miR-99b-5p and miR-191-5p transcript levels were significantly lower in TB cases. Additionally, B-cell-associated miR-320a, miR-204-5p, miR331-3p and other transcript levels were higher in TB cases. The miRNAs differentially expressed in neutrophils are predominantly implicated in signalling pathways leading to cytokine productions. Here, the decreased expression in TB cases may imply a lack of suppression on signalling pathways, which may lead to increased production of pro-inflammatory cytokines such as interferon-gamma. Furthermore, the miRNAs differentially expressed in B-cells are mostly involved in the induction/suppression of apoptosis. Further functional studies are however required to elucidate the significance and functional effects of changes in the expression of these microRNAs. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Mouse dendritic cells pulsed with capsular polysaccharide induce resistance to lethal pneumococcal challenge: roles of T cells and B cells.

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    Noam Cohen

    Full Text Available Mice are exceedingly sensitive to intra-peritoneal (IP challenge with some virulent pneumococci (LD50 = 1 bacterium. To investigate how peripheral contact with bacterial capsular polysaccharide (PS antigen can induce resistance, we pulsed bone marrow dendritic cells (BMDC of C57BL/6 mice with type 4 or type 3 PS, injected the BMDC intra-foot pad (IFP and challenged the mice IP with supra-lethal doses of pneumococci. We examined the responses of T cells and B cells in the draining popliteal lymph node and measured the effects on the bacteria in the peritoneum and blood. We now report that: 1 The PS co-localized with MHC molecules on the BMDC surface; 2 PS-specific T and B cell proliferation and IFNγ secretion was detected in the draining popliteal lymph nodes on day 4; 3 Type-specific resistance to lethal IP challenge was manifested only after day 5; 4 Type-specific IgM and IgG antibodies were detected in the sera of only some of the mice, but B cells were essential for resistance; 5 Control mice vaccinated with a single injection of soluble PS did not develop a response in the draining popliteal lymph node and were not protected; 6 Mice injected with unpulsed BMDC also did not resist challenge: In unprotected mice, pneumococci entered the blood shortly after IP inoculation and multiplied exponentially in both blood and peritoneum killing the mice within 20 hours. Mice vaccinated with PS-pulsed BMDC trapped the bacteria in the peritoneum. The trapped bacteria proliferated exponentially IP, but died suddenly at 18-20 hours. Thus, a single injection of PS antigen associated with intact BMDC is a more effective vaccine than the soluble PS alone. This model system provides a platform for studying novel aspects of PS-targeted vaccination.

  11. Prevalence of polyreactive innate clones among graft--infiltrating B cells in human cardiac allograft vasculopathy.

    Science.gov (United States)

    Chatterjee, Debanjana; Moore, Carolina; Gao, Baoshan; Clerkin, Kevin J; See, Sarah B; Shaked, David; Rogers, Kortney; Nunez, Sarah; Veras, Yokarla; Addonizio, Linda; Givertz, Michael M; Naka, Yoshifumi; Mancini, Donna; Vasilescu, Rodica; Marboe, Charles; Restaino, Susan; Madsen, Joren C; Zorn, Emmanuel

    2018-03-01

    Cardiac allograft vasculopathy (CAV) has been associated with graft-infiltrating B cells, although their characteristics are still unclear. In this study we examined the frequency, localization and reactivity profile of graft-infiltrating B cells to determine their contribution to the pathophysiology of CAV. B cells, plasma cells and macrophages were examined by immunohistochemistry in 56 allografts with CAV, 49 native failed hearts and 25 autopsy specimens. A total of 102 B-cell clones were immortalized directly from the infiltrates of 3 fresh cardiac samples with CAV. Their secreted antibodies were assessed using enzyme-linked immunoassay and flow cytometry. B-cell infiltration was observed around coronary arteries in 93% of allograft explants with CAV. Comparatively, intragraft B cells were less frequent and less dense in the intraventricular myocardium from where routine biopsies are obtained. Plasma cells and macrophages were also detected in 85% and 95% of explants, respectively. Remarkably, B-cell infiltrates were not associated with circulating donor-specific antibodies (DSA) or prior episodes of antibody-mediated rejection (AMR). Among all B-cell clones generated from 3 explants with CAV, a majority secreted natural antibodies reactive to multiple autoantigens and apoptotic cells, a characteristic of innate B cells. Our study reveals a high frequency of infiltrating B cells around the coronary arteries of allografts with CAV, independent of DSA or AMR. These cells are enriched for innate B cells with a polyreactive profile. The findings shift the focus from conventional DSA-producing B cells to the potentially pathogenic polyreactive B cells in the development of clinical CAV. Copyright © 2018 International Society for the Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

  12. Translocation of the B cell receptor to lipid rafts is inhibited in B cells from BLV-infected, persistent lymphocytosis cattle

    International Nuclear Information System (INIS)

    Hamilton, Valerie T.; Stone, Diana M.; Cantor, Glenn H.

    2003-01-01

    Bovine leukemia virus (BLV) infection causes a significant polyclonal expansion of CD5 + , IgM+ B lymphocytes known as persistent lymphocytosis (PL) in approximately 30% of infected cattle. There is evidence that this expanded B cell population has altered signaling, and resistance to apoptosis has been proposed as one mechanism of B cell expansion. In human and murine B cells, antigen binding initiates movement of the B cell receptor (BCR) into membrane microdomains enriched in sphingolipids and cholesterol, termed lipid rafts. Lipid rafts include members of the Src-family kinases and exclude certain phosphatases. Inclusion of the BCR into lipid rafts plays an important role in regulation of early signaling events and subsequent antigen internalization. Viral proteins may also influence signaling events in lipid rafts. Here we demonstrate that the largely CD5 + B cell population in PL cattle has different mobilization and internalization of the BCR when compared to the largely CD5-negative B cells in BLV-negative cattle. Unlike B cells from BLV-negative cattle, the BCR in B cells of BLV-infected, PL cattle resists movement into lipid rafts upon stimulation and is only weakly internalized. Expression of viral proteins as determined by detection of the BLV transmembrane (TM) envelope glycoprotein gp30 did not alter these events in cells from PL cattle. This exclusion of the BCR from lipid rafts may, in part, explain signaling differences seen between B cells of BLV-infected, PL, and BLV-negative cattle and the resistance to apoptosis speculated to contribute to persistent lymphocytosis

  13. TGFβ activated kinase 1 (TAK1 at the crossroad of B cell receptor and Toll-like receptor 9 signaling pathways in human B cells.

    Directory of Open Access Journals (Sweden)

    Dániel Szili

    Full Text Available B cell development and activation are regulated by combined signals mediated by the B cell receptor (BCR, receptors for the B-cell activating factor of the tumor necrosis factor family (BAFF-R and the innate receptor, Toll-like receptor 9 (TLR9. However, the underlying mechanisms by which these signals cooperate in human B cells remain unclear. Our aim was to elucidate the key signaling molecules at the crossroads of BCR, BAFF-R and TLR9 mediated pathways and to follow the functional consequences of costimulation.Therefore we stimulated purified human B cells by combinations of anti-Ig, B-cell activating factor of the tumor necrosis factor family (BAFF and the TLR9 agonist, CpG oligodeoxynucleotide. Phosphorylation status of various signaling molecules, B cell proliferation, cytokine secretion, plasma blast generation and the frequency of IgG producing cells were investigated. We have found that BCR induced signals cooperate with BAFF-R- and TLR9-mediated signals at different levels of cell activation. BCR and BAFF- as well as TLR9 and BAFF-mediated signals cooperate at NFκB activation, while BCR and TLR9 synergistically costimulate mitogen activated protein kinases (MAPKs, ERK, JNK and p38. We show here for the first time that the MAP3K7 (TGF beta activated kinase, TAK1 is responsible for the synergistic costimulation of B cells by BCR and TLR9, resulting in an enhanced cell proliferation, plasma blast generation, cytokine and antibody production. Specific inhibitor of TAK1 as well as knocking down TAK1 by siRNA abrogates the synergistic signals. We conclude that TAK1 is a key regulator of receptor crosstalk between BCR and TLR9, thus plays a critical role in B cell development and activation.

  14. Evaluation of CD307a expression patterns during normal B-cell maturation and in B-cell malignancies by flow cytometry.

    Science.gov (United States)

    Auat, Mariangeles; Cardoso, Chandra Chiappin; Santos-Pirath, Iris Mattos; Rudolf-Oliveira, Renata Cristina Messores; Matiollo, Camila; Lange, Bárbara Gil; da Silva, Jessica Pires; Dametto, Gisele Cristina; Pirolli, Mayara Marin; Colombo, Maria Daniela Holthausen Perico; Santos-Silva, Maria Claudia

    2018-02-24

    Flow cytometric immunophenotyping is deemed a fundamental tool for the diagnosis of B-cell neoplasms. Currently, the investigation of novel immunophenotypic markers has gained importance, as they can assist in the precise subclassification of B-cell malignancies by flow cytometry. Therefore, the purpose of the present study was to evaluate the expression of CD307a during normal B-cell maturation and in B-cell malignancies as well as to investigate its potential role in the differential diagnosis of these entities. CD307a expression was assessed by flow cytometry in normal precursor and mature B cells and in 115 samples collected from patients diagnosed with precursor and mature B-cell neoplasms. CD307a expression was compared between neoplastic and normal B cells. B-acute lymphoblastic leukemia cases exhibited minimal expression of CD307a, displaying a similar expression pattern to that of normal B-cell precursors. Mantle cell lymphoma (MCL) cases showed the lowest levels of CD307a among mature B-cell neoplasms. CD307a expression was statistically lower in MCL cases than in chronic B lymphocytic leukemia (CLL) and marginal zone lymphoma (MZL) cases. No statistical differences were observed between CD307a expression in neoplastic and normal plasma cells. These results indicate that the assessment of CD307a expression by flow cytometry could be helpful to distinguish CLL from MCL, and the latter from MZL. Although these results are not entirely conclusive, they provide a basis for further studies in a larger cohort of patients. © 2018 International Clinical Cytometry Society. © 2018 International Clinical Cytometry Society.

  15. Physiology of B cells in mice with X-linked immunodeficiency (xid). III. Disappearance of xid B cells in double bone marrow chimeras

    International Nuclear Information System (INIS)

    Sprent, J.; Bruce, J.

    1984-01-01

    Evidence is presented that B cells from mice with X-linked immunodeficiency (xid) differentiate at a slower rate than normal B cells. This conclusion stems from studies in which (B6 X CBA/J)F1 mice were heavily irradiated (1,000 rads) and reconstituted with a mixture of T-depleted marrow cells taken from (a) nondefective B6 mice (H-2b) and (b) xid CBA/N or nondefective CBA/Ca mice (both H-2k). With transfer of CBA/Ca plus B6 marrow cells, the irradiated recipients become repopulated with B cells derived from both parental marrow sources; except for an early imbalance (probably reflecting Hh resistance), the degree of chimerism remained relatively stable over a period of more than 6 months. Very different results occurred with transfer of a mixture of xid CBA/N and normal B6 marrow. Within the first 2 months after marrow reconstitution, a low but significant proportion of the B cells in both spleen and lymph nodes were of CBA/N origin. Thereafter the proportion of these cells fell progressively, and by 6-9 months virtually all of the B cells were of B6 origin. This gradual decline in CBA/N-derived cells did not apply to other cell types, i.e., T cells or pluripotential stem cells. Analogous results were obtained with transfer of CBA/N vs. CBA/Ca marrow cells into sublethally irradiated (750 rads) (CBA/N X DBA/2)F1 male vs. female mice. For example, CBA/N-marrow derived B cells differentiated effectively and survived for long periods in F1 male mice (xid----xid) but not in F1 female mice (xid----normal). The finding that xid B cells eventually disappear in the presence of normal B cells strengthens the view that xid B cells are an abnormal population not represented in normal mice

  16. Identification of B cells as a major site for cyprinid herpesvirus 3 latency.

    Science.gov (United States)

    Reed, Aimee N; Izume, Satoko; Dolan, Brian P; LaPatra, Scott; Kent, Michael; Dong, Jing; Jin, Ling

    2014-08-01

    Cyprinid herpesvirus 3 (CyHV-3), commonly known as koi herpesvirus (KHV), is a member of the Alloherpesviridae, and is a recently discovered emerging herpesvirus that is highly pathogenic for koi and common carp. Our previous study demonstrated that CyHV-3 becomes latent in peripheral white blood cells (WBC). In this study, CyHV-3 latency was further investigated in IgM(+) WBC. The presence of the CyHV-3 genome in IgM(+) WBC was about 20-fold greater than in IgM(-) WBC. To determine whether CyHV-3 expressed genes during latency, transcription from all eight open reading frames (ORFs) in the terminal repeat was investigated in IgM(+) WBC from koi with latent CyHV-3 infection. Only a spliced ORF6 transcript was found to be abundantly expressed in IgM(+) WBC from CyHV-3 latently infected koi. The spliced ORF6 transcript was also detected in vitro during productive infection as early as 1 day postinfection. The ORF6 transcript from in vitro infection begins at -127 bp upstream of the ATG codon and ends +188 bp downstream of the stop codon, +20 bp downstream of the polyadenylation signal. The hypothetical protein of ORF6 contains a consensus sequence with homology to a conserved domain of EBNA-3B and ICP4 from Epstein-Barr virus and herpes simplex virus 1, respectively, both members of the Herpesviridae. This is the first report of latent CyHV-3 in B cells and identification of gene transcription during latency for a member of the Alloherpesviridae. This is the first demonstration that a member of the Alloherpesviridae, cyprinid herpesvirus 3 (CyHV-3), establishes a latent infection in the B cells of its host, Cyprinus carpio. In addition, this is the first report of identification of gene transcription during latency for a member of Herpesvirales outside Herpesviridae. This is also the first report that the hypothetical protein of latent transcript of CyHV-3 contains a consensus sequence with homology to a conserved domain of EBNA-3B from Epstein-Barr virus and ICP4

  17. Suppressive effect on polyclonal B-cell activation of a synthetic peptide homologous to a transmembrane component of oncogenic retroviruses

    Energy Technology Data Exchange (ETDEWEB)

    Mitani, M.; Cianciolo, G.J.; Snyderman, R.; Yasuda, M.; Good, R.A.; Day, N.K.

    1987-01-01

    Purified feline leukemia virus, UV light-inactivated feline leukemia virus, and a synthetic peptide (CKS-17) homologous to a well-conserved region of the transmembrane components of several human and animal retroviruses were each studied for their effect on IgG production by feline peripheral blood lymphocytes. Using a reverse hemolytic plaque assay, both the viable virus and the UV-inactivated feline leukemia virus, but not the CKS-17, activated B lymphocytes to secrete IgG. When staphylococcal protein A, a polyclonal B-cell activator, was used to stimulate IgG synthesis by feline lymphocytes, the viable virus, the UV-inactivated virus, and the CKS-17 peptide each strongly suppressed IgG secretion without compromising viability of the lymphocytes. These finding suggest that the immunosuppressive influences of feline leukemia virus on immunoglobulin synthesis may reside in a conserved portion of the envelope glycoprotein that includes the region homologous to CKS-17.

  18. Suppressive effect on polyclonal B-cell activation of a synthetic peptide homologous to a transmembrane component of oncogenic retroviruses

    International Nuclear Information System (INIS)

    Mitani, M.; Cianciolo, G.J.; Snyderman, R.; Yasuda, M.; Good, R.A.; Day, N.K.

    1987-01-01

    Purified feline leukemia virus, UV light-inactivated feline leukemia virus, and a synthetic peptide (CKS-17) homologous to a well-conserved region of the transmembrane components of several human and animal retroviruses were each studied for their effect on IgG production by feline peripheral blood lymphocytes. Using a reverse hemolytic plaque assay, both the viable virus and the UV-inactivated feline leukemia virus, but not the CKS-17, activated B lymphocytes to secrete IgG. When staphylococcal protein A, a polyclonal B-cell activator, was used to stimulate IgG synthesis by feline lymphocytes, the viable virus, the UV-inactivated virus, and the CKS-17 peptide each strongly suppressed IgG secretion without compromising viability of the lymphocytes. These finding suggest that the immunosuppressive influences of feline leukemia virus on immunoglobulin synthesis may reside in a conserved portion of the envelope glycoprotein that includes the region homologous to CKS-17

  19. Multifocal Extranodal Involvement of Diffuse Large B-Cell Lymphoma

    Directory of Open Access Journals (Sweden)

    Devrim Cabuk

    2013-01-01

    Full Text Available Endobronchial involvement of extrapulmonary malignant tumors is uncommon and mostly associated with breast, kidney, colon, and rectum carcinomas. A 68-year-old male with a prior diagnosis of colon non-Hodgkin lymphoma (NHL was admitted to the hospital with a complaint of cough, sputum, and dyspnea. The chest radiograph showed right hilar enlargement and opacity at the right middle zone suggestive of a mass lesion. Computed tomography of thorax revealed a right-sided mass lesion extending to thoracic wall with the destruction of the third and the fourth ribs and a right hilar mass lesion. Fiberoptic bronchoscopy was performed in order to evaluate endobronchial involvement and showed stenosis with mucosal tumor infiltration in right upper lobe bronchus. The pathological examination of bronchoscopic biopsy specimen reported diffuse large B-cell lymphoma and the patient was accepted as the endobronchial recurrence of sigmoid colon NHL. The patient is still under treatment of R-ICE (rituximab-ifosfamide-carboplatin-etoposide chemotherapy and partial regression of pulmonary lesions was noted after 3 courses of treatment.

  20. Prognostic Assessment in Patients with Indolent B-Cell Lymphomas

    Directory of Open Access Journals (Sweden)

    Luca Arcaini

    2012-01-01

    Full Text Available Follicular lymphoma (FL is an indolent lymphoma with long median survival. Many studies have been performed to build up prognostic scores potentially useful to identify patients with poorer outcome. In 2004, an international consortium coordinated by the International Follicular Lymphoma Prognostic Factor project was established and a new prognostic study was launched (FLIPI2 using progression-free survival (PFS as main endpoint and integrating all the modern parameters prospectively collected. Low-grade non-Hodgkin lymphomas were once considered as a heterogenous group of lymphomas characterized by an indolent clinical course. Each entity is characterized by unique clinicobiologic features. Some studies have been focused on prognostic factors in single lymphoma subtypes, with the development of specific-entity scores based on retrospective series, for instance splenic marginal zone lymphoma (SMZL. A widely accepted prognostic tool for clinical usage for indolent non-follicular B-cell lymphomas is largely awaited. In this paper we summarized the current evidence regarding prognostic assessment of indolent follicular and non-follicular lymphomas.

  1. B Cell Intrinsic Mechanisms Constraining IgE Memory

    Directory of Open Access Journals (Sweden)

    Brice Laffleur

    2017-11-01

    Full Text Available Memory B cells and long-lived plasma cells are key elements of adaptive humoral immunity. Regardless of the immunoglobulin class produced, these cells can ensure long-lasting protection but also long-lasting immunopathology, thus requiring tight regulation of their generation and survival. Among all antibody classes, this is especially true for IgE, which stands as the most potent, and can trigger dramatic inflammatory reactions even when present in minute amounts. IgE responses and memory crucially protect against parasites and toxic components of venoms, conferring selective advantages and explaining their conservation in all mammalian species despite a parallel broad spectrum of IgE-mediated immunopathology. Long-term memory of sensitization and anaphylactic responses to allergens constitute the dark side of IgE responses, which can trigger multiple acute or chronic pathologic manifestations, some punctuated with life-threatening events. This Janus face of the IgE response and memory, both necessary and potentially dangerous, thus obviously deserves the most elaborated self-control schemes.

  2. Epigenetic Heterogeneity of B-Cell Lymphoma: Chromatin Modifiers

    Science.gov (United States)

    Hopp, Lydia; Nersisyan, Lilit; Löffler-Wirth, Henry; Arakelyan, Arsen; Binder, Hans

    2015-01-01

    We systematically studied the expression of more than fifty histone and DNA (de)methylating enzymes in lymphoma and healthy controls. As a main result, we found that the expression levels of nearly all enzymes become markedly disturbed in lymphoma, suggesting deregulation of large parts of the epigenetic machinery. We discuss the effect of DNA promoter methylation and of transcriptional activity in the context of mutated epigenetic modifiers such as EZH2 and MLL2. As another mechanism, we studied the coupling between the energy metabolism and epigenetics via metabolites that act as cofactors of JmjC-type demethylases. Our study results suggest that Burkitt’s lymphoma and diffuse large B-cell Lymphoma differ by an imbalance of repressive and poised promoters, which is governed predominantly by the activity of methyltransferases and the underrepresentation of demethylases in this regulation. The data further suggest that coupling of epigenetics with the energy metabolism can also be an important factor in lymphomagenesis in the absence of direct mutations of genes in metabolic pathways. Understanding of epigenetic deregulation in lymphoma and possibly in cancers in general must go beyond simple schemes using only a few modes of regulation. PMID:26506391

  3. Epigenetic Heterogeneity of B-Cell Lymphoma: Chromatin Modifiers

    Directory of Open Access Journals (Sweden)

    Lydia Hopp

    2015-10-01

    Full Text Available We systematically studied the expression of more than fifty histone and DNA (demethylating enzymes in lymphoma and healthy controls. As a main result, we found that the expression levels of nearly all enzymes become markedly disturbed in lymphoma, suggesting deregulation of large parts of the epigenetic machinery. We discuss the effect of DNA promoter methylation and of transcriptional activity in the context of mutated epigenetic modifiers such as EZH2 and MLL2. As another mechanism, we studied the coupling between the energy metabolism and epigenetics via metabolites that act as cofactors of JmjC-type demethylases. Our study results suggest that Burkitt’s lymphoma and diffuse large B-cell Lymphoma differ by an imbalance of repressive and poised promoters, which is governed predominantly by the activity of methyltransferases and the underrepresentation of demethylases in this regulation. The data further suggest that coupling of epigenetics with the energy metabolism can also be an important factor in lymphomagenesis in the absence of direct mutations of genes in metabolic pathways. Understanding of epigenetic deregulation in lymphoma and possibly in cancers in general must go beyond simple schemes using only a few modes of regulation.

  4. EVALUATION OF CYTOKINE GENE POLYMORPHISM IN B CELL LYMPHOID MALIGNANCIES

    Directory of Open Access Journals (Sweden)

    E. L. Nazarova

    2014-01-01

    Full Text Available Previous studies with some solid tumors has shown that polymorphisms of certain cytokine genes may be used as predictors of clinical outcome in the patients. It seemed important to evaluate potential correlations between production of certain pro- and anti-inflammatory cytokines and co-receptor molecules, and promoter polymorphism of the cytokine genes involved into regulation of cell proliferation, differentiation, apoptosis, lipid metabolism and blood clotting in the patients with hematological malignancies. The article contains our results concerning associations between of IL-1β, -2, -4, -10, -17, TNFα, and allelic polymorphisms of their genes in 62 patients with B cell lymphoid malignancies in an ethnically homogenous group (self-identified as Russians. We have shown that the GА and AA genotypes of the G-308A polymorphism in TNFα gene are significantly associated with increased production of this cytokine, being more common in aggressive non-Hodgkin lymphomas, more rare in multiple myeloma and in indolent non-Hodgkin lymphomas.

  5. Antibody and B cell responses to Plasmodium sporozoites

    Directory of Open Access Journals (Sweden)

    Johanna N Dups

    2014-11-01

    Full Text Available Antibodies are capable of blocking infection of the liver by Plasmodium sporozoites. Accordingly the induction of anti-sporozoite antibodies is a major aim of various vaccine approaches to malaria. In recent years our knowledge of the specificity and quantities of antibodies required for protection has been greatly expanded by clinical trials of various whole sporozoite and subunit vaccines. Moreover, the development of humanized mouse models and transgenic parasites have also aided our ability to assess the specificity of antibodies and their ability to block infection. Nonetheless, considerable gaps remain in our knowledge - in particular in understanding what antigens are recognized by infection blocking antibodies and in knowing how we can induce robust, long-lived antibody responses. Maintaining high levels of circulating antibodies is likely to be of primary importance, as antibodies must block infection in the short time it takes for sporozoites to reach the liver from the skin. It is clear that a better understanding of the development of protective B cell-mediated immunity will aid the development and refinement of malaria vaccines.

  6. Changes in B Cell Populations and Merozoite Surface Protein-1-Specific Memory B Cell Responses after Prolonged Absence of Detectable P. falciparum Infection.

    Directory of Open Access Journals (Sweden)

    Cyrus Ayieko

    Full Text Available Clinical immunity to malaria declines in the absence of repeated parasite exposure. However, little is known about how B cell populations and antigen-specific memory B cells change in the absence of P. falciparum infection. A successful indoor residual insecticide spraying campaign in a highland area of western Kenya, led to an absence of blood-stage P. falciparum infection between March 2007 and April 2008. We assessed memory B cell responses in 45 adults at the beginning (April 2008 and end (April 2009 of a subsequent 12-month period during which none of the adults had evidence of asymptomatic parasitemia or clinical disease. Antibodies and memory B cells to the 42-kDa portion of the merozoite surface protein-1 (MSP-142 were measured using ELISA and ELISPOT assays, respectively. B cell populations were characterized by flow cytometry. From 2008 to 2009, the prevalence of MSP-142-specific memory B cells (45% vs. 55%, respectively, P = 0.32 or antibodies (91% vs. 82%, respectively, P = 0.32 did not differ significantly, although specific individuals did change from positive to negative and vice versa, particularly for memory B cells, suggesting possible low-level undetected parasitemia may have occurred in some individuals. The magnitude of MSP-142-specific memory B cells and levels of antibodies to MSP-142 also did not differ from 2008 to 2009 (P>0.10 for both. However, from 2008 to 2009 the proportions of both class-switched atypical (CD19+IgD-CD27-CD21-IgM- and class-switched activated (CD19+IgD-CD27+CD21-IgM- memory B cells decreased (both P<0.001. In contrast, class-switched resting classical memory B cells (CD19+IgD-CD27+CD21+IgM- increased (P<0.001. In this area of seasonal malaria transmission, a one- year absence of detectable P. falciparum infection was not associated with changes in the prevalence or level of MSP-142 specific memory B cells, but was associated with major changes in overall memory B cell subsets.

  7. Multi-compartment Aerosol Transport Model

    Energy Technology Data Exchange (ETDEWEB)

    Hubbard, Joshua Allen; Santarpia, Joshua; Brotherton, Christopher M.; Omana, Michael Alexis; Rivera, Danielle; Lucero, Gabriel Anthony

    2017-06-01

    A simple aerosol transport model was developed for a multi-compartmented cleanroom. Each compartment was treated as a well-mixed volume with ventilating supply and return air. Gravitational settling, intercompartment transport, and leakage of exterior air into the system were included in the model. A set of first order, coupled, ordinary differential equations was derived from the conservation equations of aerosol mass and air mass. The system of ODEs was then solved in MATLAB using pre-existing numerical methods. The model was verified against cases of (1) constant inlet-duct concentration, and (2) exponentially decaying inlet-duct concentration. Numerical methods resulted in normalized error of less than 10 -9 when model solutions were compared to analytical solutions. The model was validated against experimental measurements from a single field test and showed good agreement in the shape and magnitude of the aerosol concentration profile with time.

  8. A modern definition of mediastinal compartments.

    Science.gov (United States)

    Carter, Brett W; Tomiyama, Noriyuki; Bhora, Faiz Y; Rosado de Christenson, Melissa L; Nakajima, Jun; Boiselle, Phillip M; Detterbeck, Frank C; Marom, Edith M

    2014-09-01

    Division of the mediastinum into compartments is used to help narrow the differential diagnosis of newly detected mediastinal masses, to assist in planning biopsy and surgical procedures, and to facilitate communication among clinicians of multiple disciplines. Several traditional mediastinal division schemes exist based upon arbitrary landmarks on the lateral chest radiograph. We describe a modern, computed tomography-based mediastinal division scheme, which has been accepted by the International Thymic Malignancy Interest Group as a new standard. This clinical classification defines a prevascular (anterior), a visceral (middle), and a paravertebral (posterior) compartment, with anatomic boundaries defined clearly by computed tomography. It is our intention that this definition be used in the reporting of clinical cases and the design of prospective clinical trials.

  9. Hermetic compartments leak-tightness enhancement

    International Nuclear Information System (INIS)

    Murani, J.

    2000-01-01

    In connection with the enhancement of the nuclear safety of the Jaslovske Bohunice V-1 NPP actions for the increase of the leak tightness are performed. The reconstruction has been done in the following directions: hermetic compartments leak tightness enhancement; air lock installation; installation of air lock in SP 4 vent system; integrated leakage rate test to hermetic compartments with leak detection. After 'major' leaks on the hermetic boundary components had been eliminated, since 1994 works on a higher qualitative level began. The essence of the works consists in the detection and identification of leaks in the structural component of the hermetic boundary during the planned refueling outages. The results of the Small Reconstruction and gradual enhancement of leak tightness are presented

  10. Monoterpene biosynthesis potential of plant subcellular compartments.

    Science.gov (United States)

    Dong, Lemeng; Jongedijk, Esmer; Bouwmeester, Harro; Van Der Krol, Alexander

    2016-01-01

    Subcellular monoterpene biosynthesis capacity based on local geranyl diphosphate (GDP) availability or locally boosted GDP production was determined for plastids, cytosol and mitochondria. A geraniol synthase (GES) was targeted to plastids, cytosol, or mitochondria. Transient expression in Nicotiana benthamiana indicated local GDP availability for each compartment but resulted in different product levels. A GDP synthase from Picea abies (PaGDPS1) was shown to boost GDP production. PaGDPS1 was also targeted to plastids, cytosol or mitochondria and PaGDPS1 and GES were coexpressed in all possible combinations. Geraniol and geraniol-derived products were analyzed by GC-MS and LC-MS, respectively. GES product levels were highest for plastid-targeted GES, followed by mitochondrial- and then cytosolic-targeted GES. For each compartment local boosting of GDP biosynthesis increased GES product levels. GDP exchange between compartments is not equal: while no GDP is exchanged from the cytosol to the plastids, 100% of GDP in mitochondria can be exchanged to plastids, while only 7% of GDP from plastids is available for mitochondria. This suggests a direct exchange mechanism for GDP between plastids and mitochondria. Cytosolic PaGDPS1 competes with plastidial GES activity, suggesting an effective drain of isopentenyl diphosphate from the plastids to the cytosol. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  11. Perfluoroalkyl acid distribution in various plant compartments ...

    Science.gov (United States)

    Crop uptake of perfluoroalkyl acids (PFAAs) from biosolids-amended soil has been identified as a potential pathway for PFAA entry into the terrestrial food chain. This study compared the uptake of PFAAs in greenhouse-grown radish (Raphanus sativus), celery (Apium graveolens var.dulce), tomato (Lycopersicon lycopersicum), and sugar snap pea (Pisum sativum var. macrocarpon) from an industrially impacted biosolids-amended soil, a municipal biosolids­ amended soil, and a control soil. Individual concentrations of PFAAs, on a dry weight basis, in mature, edible portions of crops grown in soil amended with PFAA industrially impacted biosolids were highest for perfluorooctanoate (PFOA; 67 ng/g) in radish root, perfluorobutanoate (PFBA;232 ng/g) in celery shoot, and PFBA (150 ng/g) in pea fruit. Comparatively, PFAA concentrations in edible compartments of crops grown in the municipal biosolids-amended soil and in the control soil were less than 25 ng/g. Bioaccumulation factors (BAFs) were calculated for the root, shoot, and fruit compartments (as applicable) of all crops grown in the industrially impacted soil. BAFs were highest for PFBA in the shoots of all crops, as well as in the fruit compartment of pea. Root­ soil concentration factors (RCFs) for tomato and pea were independent of PFAA chain length, while radish and celery RCFs showed a slight decrease with increasing chain length. Shoot-soil concentration factors (SCFs) for all crops showed a decrease with incre

  12. Salus: Kernel Support for Secure Process Compartments

    Directory of Open Access Journals (Sweden)

    Raoul Strackx

    2015-01-01

    Full Text Available Consumer devices are increasingly being used to perform security and privacy critical tasks. The software used to perform these tasks is often vulnerable to attacks, due to bugs in the application itself or in included software libraries. Recent work proposes the isolation of security-sensitive parts of applications into protected modules, each of which can be accessed only through a predefined public interface. But most parts of an application can be considered security-sensitive at some level, and an attacker who is able to gain inapplication level access may be able to abuse services from protected modules. We propose Salus, a Linux kernel modification that provides a novel approach for partitioning processes into isolated compartments sharing the same address space. Salus significantly reduces the impact of insecure interfaces and vulnerable compartments by enabling compartments (1 to restrict the system calls they are allowed to perform, (2 to authenticate their callers and callees and (3 to enforce that they can only be accessed via unforgeable references. We describe the design of Salus, report on a prototype implementation and evaluate it in terms of security and performance. We show that Salus provides a significant security improvement with a low performance overhead, without relying on any non-standard hardware support.

  13. Evaluation of acute compartment syndrome of extremities in ...

    African Journals Online (AJOL)

    Arun Kumar Agnihotri

    compartment syndrome in children; Acute compartment syndrome and fasciotomy. INTRODUCTIONᴪ .... these patients were manipulated under general anaesthesia ... of these children. The clinical diagnosis of increased ICP is not easy.

  14. Compartment syndrome can also be seen in the forearm

    DEFF Research Database (Denmark)

    Asmar, Ali; Broholm, Rikke; Bülow, Jens

    2014-01-01

    Chronic compartment syndrome is a challenge for the clinician and symptomatic similar to neuropathies, tenosynovitis, stress fractures and referred pain from lumbar cervicalis. Thus, chronic compartment syndrome of the upper extremities is probably an underdiagnosed condition. In patients...

  15. 14 CFR 23.853 - Passenger and crew compartment interiors.

    Science.gov (United States)

    2010-01-01

    ... Photographic Film PH1.25 (available from the American National Standards Institute, 1430 Broadway, New York, N... stowage compartments and compartments for stowing small items such as magazines and maps) must be self...

  16. B cell depletion reduces T cell activation in pancreatic islets in a murine autoimmune diabetes model.

    Science.gov (United States)

    Da Rosa, Larissa C; Boldison, Joanne; De Leenheer, Evy; Davies, Joanne; Wen, Li; Wong, F Susan

    2018-06-01

    Type 1 diabetes is a T cell-mediated autoimmune disease characterised by the destruction of beta cells in the islets of Langerhans, resulting in deficient insulin production. B cell depletion therapy has proved successful in preventing diabetes and restoring euglycaemia in animal models of diabetes, as well as in preserving beta cell function in clinical trials in the short term. We aimed to report a full characterisation of B cell kinetics post B cell depletion, with a focus on pancreatic islets. Transgenic NOD mice with a human CD20 transgene expressed on B cells were injected with an anti-CD20 depleting antibody. B cells were analysed using multivariable flow cytometry. There was a 10 week delay in the onset of diabetes when comparing control and experimental groups, although the final difference in the diabetes incidence, following prolonged observation, was not statistically significant (p = 0.07). The co-stimulatory molecules CD80 and CD86 were reduced on stimulation of B cells during B cell depletion and repopulation. IL-10-producing regulatory B cells were not induced in repopulated B cells in the periphery, post anti-CD20 depletion. However, the early depletion of B cells had a marked effect on T cells in the local islet infiltrate. We demonstrated a lack of T cell activation, specifically with reduced CD44 expression and effector function, including IFN-γ production from both CD4 + and CD8 + T cells. These CD8 + T cells remained altered in the pancreatic islets long after B cell depletion and repopulation. Our findings suggest that B cell depletion can have an impact on T cell regulation, inducing a durable effect that is present long after repopulation. We suggest that this local effect of reducing autoimmune T cell activity contributes to delay in the onset of autoimmune diabetes.

  17. Recombinant human interleukin 2 acts as a B cell growth and differentiation promoting factor

    OpenAIRE

    Emmrich, F.; Moll, Heidrun; Simon, Markus M.

    2009-01-01

    Human B cells appropriately activated by a B cell mitogen are rendered susceptible to human Interleukin 2 (IL-2) as demonstrated with recombinant human IL-2 (rec. h IL-2). They show increased proliferation and drastically enhanced immunoglobulin secretion. Susceptibility to IL-2 is accompanied with the expression of the IL-2 receptor (Tac antigen) on B cells. The data suggest that IL-2 is one of the lymphokines directly involved in the activation of B lymphocytes.

  18. Aborted germinal center reactions and B cell memory by follicular T cells specific for a B cell receptor V region peptide.

    Science.gov (United States)

    Heiser, Ryan A; Snyder, Christopher M; St Clair, James; Wysocki, Lawrence J

    2011-07-01

    A fundamental problem in immunoregulation is how CD4(+) T cells react to immunogenic peptides derived from the V region of the BCR that are created by somatic mechanisms, presented in MHC II, and amplified to abundance by B cell clonal expansion during immunity. BCR neo Ags open a potentially dangerous avenue of T cell help in violation of the principle of linked Ag recognition. To analyze this issue, we developed a murine adoptive transfer model using paired donor B cells and CD4 T cells specific for a BCR-derived peptide. BCR peptide-specific T cells aborted ongoing germinal center reactions and impeded the secondary immune response. Instead, they induced the B cells to differentiate into short-lived extrafollicular plasmablasts that secreted modest quantities of Ig. These results uncover an immunoregulatory process that restricts the memory pathway to B cells that communicate with CD4 T cells via exogenous foreign Ag.

  19. EBI2 overexpression in mice leads to B1 B cell expansion and chronic lymphocytic leukemia-(CLL)-like B cell malignancies

    DEFF Research Database (Denmark)

    Niss Arfelt, Kristine; Barington, Line; Benned-Jensen, Tau

    2017-01-01

    -targeted expression of human EBI2 in mice reduces germinal center-dependent immune responses, reduces total IgM and IgG levels, and leads to increased proliferation and upregulation of cellular oncogenes. Furthermore, hEBI2 overexpression leads to an abnormally expanded CD5+ B1a B cell subset present as early as 4......Human and mouse chronic lymphocytic leukemia (CLL) develop from CD5+ B cells that in mice and macaques are known to define the distinct B1a B cell lineage. B1a cells are characterized by lack of germinal center development and the B1a cell population is increased in mice with reduced germinal...... cells towards the extrafollicular area, whereas downregulation is essential for germinal center formation. We therefore speculated whether increased expression of EBI2 would lead to an expanded B1 cell subset and, ultimately, progression to chronic lymphocytic leukemia. Here we demonstrate that B cell...

  20. One Patient, Two Uncommon B-Cell Neoplasms: Solitary Plasmacytoma following Complete Remission from Intravascular Large B-Cell Lymphoma Involving Central Nervous System

    Directory of Open Access Journals (Sweden)

    Joycelyn Lee

    2014-01-01

    Full Text Available Second lymphoid neoplasms are an uncommon but recognized feature of non-Hodgkin’s lymphomas, putatively arising secondary to common genetic or environmental risk factors. Previous limited evaluations of clonal relatedness between successive mature B-cell malignancies have yielded mixed results. We describe the case of a man with intravascular large B-cell lymphoma involving the central nervous system who went into clinical remission following immunochemotherapy and brain radiation, only to relapse 2 years later with a plasmacytoma of bone causing cauda equina syndrome. The plasmacytoma stained strongly for the cell cycle regulator cyclin D1 on immunohistochemistry, while the original intravascular large cell lymphoma was negative, a disparity providing no support for clonal identity between the 2 neoplasms. Continued efforts atcataloging and evaluating unique associations of B-cell malignancies are critical to improving understanding of overarching disease biology in B-cell malignancies.

  1. Clonal dominance and transplantation dynamics in hematopoietic stem cell compartments.

    Directory of Open Access Journals (Sweden)

    Peter Ashcroft

    2017-10-01

    Full Text Available Hematopoietic stem cells in mammals are known to reside mostly in the bone marrow, but also transitively passage in small numbers in the blood. Experimental findings have suggested that they exist in a dynamic equilibrium, continuously migrating between these two compartments. Here we construct an individual-based mathematical model of this process, which is parametrised using existing empirical findings from mice. This approach allows us to quantify the amount of migration between the bone marrow niches and the peripheral blood. We use this model to investigate clonal hematopoiesis, which is a significant risk factor for hematologic cancers. We also analyse the engraftment of donor stem cells into non-conditioned and conditioned hosts, quantifying the impact of different treatment scenarios. The simplicity of the model permits a thorough mathematical analysis, providing deeper insights into the dynamics of both the model and of the real-world system. We predict the time taken for mutant clones to expand within a host, as well as chimerism levels that can be expected following transplantation therapy, and the probability that a preconditioned host is reconstituted by donor cells.

  2. B Cells Promote Th1- Skewed NKT Cell Response by CD1d-TCR Interaction

    OpenAIRE

    Shin, Jung Hoon; Park, Se-Ho

    2013-01-01

    CD1d expressing dendritic cells (DCs) are good glyco-lipid antigen presenting cells for NKT cells. However, resting B cells are very weak stimulators for NKT cells. Although ?-galactosylceramide (?-GalCer) loaded B cells can activate NKT cells, it is not well defined whether B cells interfere NKT cell stimulating activity of DCs. Unexpectedly, we found in this study that B cells can promote Th1-skewed NKT cell response, which means a increased level of IFN-? by NKT cells, concomitant with a d...

  3. Molecular characterization of neoplastic and normal "sister" lymphoblastoid B-cell lines from chronic lymphocytic leukemia

    DEFF Research Database (Denmark)

    Lanemo Myhrinder, Anna; Hellqvist, Eva; Bergh, Ann-Charlotte

    2013-01-01

    Chronic lymphocytic leukemia (CLL) B-cells resemble self-renewing CD5 + B-cells carrying auto/xeno-antigen-reactive B-cell receptors (BCRs) and multiple innate pattern-recognition receptors, such as Toll-like receptors and scavenger receptors. Integration of signals from BCRs with multiple surface...... a comprehensive genotypic and phenotypic characterization of available CLL and normal B-cell-derived lymphoblastoid cell lines (LCLs) from the same individuals (n = 17). Authenticity and verification studies of CLL-patient origin were done by IGHV sequencing, fluorescence in situ hybridization (FISH) and DNA...

  4. Human B cells produce chemokine CXCL10 in the presence of Mycobacterium tuberculosis specific T cells

    DEFF Research Database (Denmark)

    Hoff, Soren T; Salman, Ahmed M; Ruhwald, Morten

    2015-01-01

    BACKGROUND: The role of B cells in human host response to Mycobacterium tuberculosis (Mtb) infection is still controversial, but recent evidence suggest that B cell follicle like structures within the lung may influence host responses through regulation of the local cytokine environment. A candid......BACKGROUND: The role of B cells in human host response to Mycobacterium tuberculosis (Mtb) infection is still controversial, but recent evidence suggest that B cell follicle like structures within the lung may influence host responses through regulation of the local cytokine environment...

  5. Radioimmunotherapy of B-cell non-Hodgkin’s lymphoma

    Directory of Open Access Journals (Sweden)

    Caroline eBodet-Milin

    2013-07-01

    Full Text Available This manuscript reviews current advances in the use of radioimmunotherapy (RIT for the treatment of B-cell non-Hodgkin’s lymphoma (NHL. RIT has been in use for more than 20 years and has progressed significantly with the discovery of new molecular targets, the development of new stable chelates, the humanization of monoclonal antibodies (MAbs, and the use of pretargeting techniques. Today, two products targeting the CD20 antigen are approved: 131I-tositumomab, (Bexxar® and 90Y-ibritumomab tiuxetan, (Zevalin®. 131I-tositumomab is available in the United States, and 90Y-ibritumumab tiuxetan in Europe, the United States, Asia, and Africa. RIT can be integrated in clinical practice using non-ablative activities for treatment of patients with relapsed or refractory follicular lymphoma (FL or as consolidation after induction chemotherapy in front-line treatment in FL patients. Despite the lack of phase III studies to clearly define the efficacy of RIT in the management of B lymphoma in the era of rituximab-based therapy, RIT efficacy in NHL has been demonstrated. In relapsing refractory FL and transformed NHL, RIT as a monotherapy induces around 30% complete response with a possibility of durable remissions. RIT consolidation after induction therapy significantly improves the quality of the response. Dose-limiting toxicity of RIT is hematological, depending on bone marrow involvement and prior treatment. Non-hematological toxicity is generally low. Different studies have been published assessing innovative protocols of RIT or new indications, in particular treatment in patients with aggressive lymphomas. High-dose treatment, RIT as consolidation after different therapeutic induction modalities, RIT in first-line treatment or fractionated RIT showed promising results. New MAbs, in particular humanized MAbs, or combinations of naked and radiolabeled MAbs, also appear promising. Personalized dosimetry protocols should be developed to determine

  6. B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and classical Burkitt's lymphoma: A case report and review

    OpenAIRE

    Chettiankandy, Tabita Joy; Tupkari, Jagdish Vishnu; Kumar, Keshav; Ahire, Manisha Sandeep

    2016-01-01

    B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma (DLBCL) and classical Burkitt's lymphoma (BL), is a diagnostic provisional category in the World Health Organization 2008 classification of lymphomas. This category was designed as a measure to accommodate borderline cases that cannot be reliably classified into a single distinct disease entity after all available morphological, immunophenotypical and molecular studies have been performed. Typica...

  7. 46 CFR 169.627 - Compartments containing diesel fuel tanks.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Compartments containing diesel fuel tanks. 169.627... SCHOOL VESSELS Machinery and Electrical Ventilation § 169.627 Compartments containing diesel fuel tanks. Unless they are adequately ventilated, enclosed compartments or spaces containing diesel fuel tanks and...

  8. Plasma and memory B-cell kinetics in infants following a primary schedule of CRM 197-conjugated serogroup C meningococcal polysaccharide vaccine.

    Science.gov (United States)

    Kelly, Dominic F; Snape, Matthew D; Perrett, Kirsten P; Clutterbuck, Elizabeth A; Lewis, Susan; Blanchard Rohner, Geraldine; Jones, Meryl; Yu, Ly-Mee; Pollard, Andrew J

    2009-05-01

    The induction of persistent protective levels of pathogen-specific antibody is an important goal of immunization against childhood infections. However, antibody persistence is poor after immunization in infancy versus later in life. Serogroup C meningococci (MenC) are an important cause of bacteraemia and meningitis in children. The use of protein-polysaccharide conjugate vaccines against MenC has been associated with a significant decline in the incidence of invasive disease. However, vaccine effectiveness is negligible by more than 1 year after a three-dose priming series in infancy and corresponds to a rapid decline in antibody following an initial immune response. The cellular mechanisms underlying the generation of persistent antibody in this age group are unclear. An essential prelude to larger studies of peripheral blood B cells is an understanding of B-cell kinetics following immunization. We measured MenC- and diphtheria-specific plasma and memory B-cell kinetics in infants receiving a CRM(197) (cross-reactive material; mutant diphtheria toxoid)-conjugated MenC vaccine at 2, 3 and 4 months of age. Plasma cell responses were more delayed after the first dose when compared with the rapid appearance of plasma cells after the third dose. Memory B cells were detectable at all time-points following the third dose as opposed to the low frequency seen following a first dose. This study provides data on B-cell kinetics following a primary schedule of immunization in young infants upon which to base further studies of the underlying cellular mechanism of humoral immunity.

  9. Propylthiouracil and peripheral neuropathy

    Directory of Open Access Journals (Sweden)

    Valentina Van Boekel

    1992-06-01

    Full Text Available Peripheral neuropathy is a rare manifestation in hyperthyroidism. We describe the neurological manifestations of a 38 year old female with Graves' disease who developed peripheral neuropathy in the course of her treatment with propylthiouracil. After the drug was tapered off, the neurological signs disappeared. Therefore, we call attention for a possible toxic effect on peripheral nervous system caused by this drug.

  10. Prediction of linear B-cell epitopes of hepatitis C virus for vaccine development

    Science.gov (United States)

    2015-01-01

    Background High genetic heterogeneity in the hepatitis C virus (HCV) is the major challenge of the development of an effective vaccine. Existing studies for developing HCV vaccines have mainly focused on T-cell immune response. However, identification of linear B-cell epitopes that can stimulate B-cell response is one of the major tasks of peptide-based vaccine development. Owing to the variability in B-cell epitope length, the prediction of B-cell epitopes is much more complex than that of T-cell epitopes. Furthermore, the motifs of linear B-cell epitopes in different pathogens are quite different (e. g. HCV and hepatitis B virus). To cope with this challenge, this work aims to propose an HCV-customized sequence-based prediction method to identify B-cell epitopes of HCV. Results This work establishes an experimentally verified dataset comprising the B-cell response of HCV dataset consisting of 774 linear B-cell epitopes and 774 non B-cell epitopes from the Immune Epitope Database. An interpretable rule mining system of B-cell epitopes (IRMS-BE) is proposed to select informative physicochemical properties (PCPs) and then extracts several if-then rule-based knowledge for identifying B-cell epitopes. A web server Bcell-HCV was implemented using an SVM with the 34 informative PCPs, which achieved a training accuracy of 79.7% and test accuracy of 70.7% better than the SVM-based methods for identifying B-cell epitopes of HCV and the two general-purpose methods. This work performs advanced analysis of the 34 informative properties, and the results indicate that the most effective property is the alpha-helix structure of epitopes, which influences the connection between host cells and the E2 proteins of HCV. Furthermore, 12 interpretable rules are acquired from top-five PCPs and achieve a sensitivity of 75.6% and specificity of 71.3%. Finally, a conserved promising vaccine candidate, PDREMVLYQE, is identified for inclusion in a vaccine against HCV. Conclusions This work

  11. B-cell receptor signaling as a driver of lymphoma development and evolution.

    Science.gov (United States)

    Niemann, Carsten U; Wiestner, Adrian

    2013-12-01

    The B-cell receptor (BCR) is essential for normal B-cell development and maturation. In an increasing number of B-cell malignancies, BCR signaling is implicated as a pivotal pathway in tumorigenesis. Mechanisms of BCR activation are quite diverse and range from chronic antigenic drive by microbial or viral antigens to autostimulation of B-cells by self-antigens to activating mutations in intracellular components of the BCR pathway. Hepatitis C virus infection can lead to the development of splenic marginal zone lymphoma, while Helicobacter pylori infection is associated with the development of mucosa-associated lymphoid tissue lymphomas. In some of these cases, successful treatment of the infection removes the inciting antigen and results in resolution of the lymphoma. Chronic lymphocytic leukemia has been recognized for decades as a malignancy of auto-reactive B-cells and its clinical course is in part determined by the differential response of the malignant cells to BCR activation. In a number of B-cell malignancies, activating mutations in signal transduction components of the BCR pathway have been identified; prominent examples are activated B-cell-like (ABC) diffuse large B-cell lymphomas (DLBCL) that carry mutations in CD79B and CARD11 and display chronic active BCR signaling resulting in constitutive activation of the NF-κB pathway. Despite considerable heterogeneity in biology and clinical course, many mature B-cell malignancies are highly sensitive to kinase inhibitors that disrupt BCR signaling. Thus, targeted therapy through inhibition of BCR signaling is emerging as a new treatment paradigm for many B-cell malignancies. Here, we review the role of the BCR in the pathogenesis of B-cell malignancies and summarize clinical results of the emerging class of kinase inhibitors that target this pathway. Copyright © 2013. Published by Elsevier Ltd.

  12. Enteral Feeding in Abdominal Compartment Syndrome

    Directory of Open Access Journals (Sweden)

    Ye. V Grigoryev

    2009-01-01

    Full Text Available Objective: to substantiate the choice of a gastrointestinal tract (GIT function support regimen as a mode for correction of the abdominal compartment syndrome (ACS. Subjects and methods. Forty-three patients with different causes of inadequate GIT function of various origin and ACS (disseminated peritonitis (45%, pancreatitis (24%, and severe concomitant injury (31% were examined. Group 1 (control received complete parenteral nutritional feeding (n=23; APACHE II scores, 21±4; calculated probability of fatal outcome, 33.5%. In Group II (study, complete parenteral feeding in the first 24 hours after stabilization was supplemented with GIT function support with Pepsisorb (Nutricia in doses of 500, 1000, and 1500 ml on days 1, 2, and 3, respectively (n=20; APACHE II scores, 20±6; calculated probability of fatal outcome, 37.1%. During early enteral nutritional support, the SOFA score was significantly less than that in Group 1 on days 2—3; the oxygenation index significantly increased on day 3; the value of intra-abdominal hypertension decreased to the control values. The positive effect of the GIT function support regimen on regression of the multiple organ dysfunction syndrome (MODS was confirmed by the lowered levels of biological markers (von Willebrand factor (WF and endothelin-1 as markers of endothelial damage of MODS. Correlation analysis showed a direct correlation between the markers of endothelial damage and the SOFA scores (r=0.34; p=0.05 for WF and r=0.49;p=0.03 for endothelin. Conclusion. The GIT function support regimen via early enteral alimentation with Peptisorb, which was initiated in the first 24 hours after admission, is able to level off the manifestations of the early stages of the abdominal compartment syndrome, with the acceptable values of oxygen balance and water-electrolyte and osmotic homeostasis being achieved. Key words: abdominal compartment syndrome, nutritional support, biological markers, oxygenation index

  13. Logical analysis of diffuse large B-cell lymphomas.

    Science.gov (United States)

    Alexe, G; Alexe, S; Axelrod, D E; Hammer, P L; Weissmann, D

    2005-07-01

    The goal of this study is to re-examine the oligonucleotide microarray dataset of Shipp et al., which contains the intensity levels of 6817 genes of 58 patients with diffuse large B-cell lymphoma (DLBCL) and 19 with follicular lymphoma (FL), by means of the combinatorics, optimisation, and logic-based methodology of logical analysis of data (LAD). The motivations for this new analysis included the previously demonstrated capabilities of LAD and its expected potential (1) to identify different informative genes than those discovered by conventional statistical methods, (2) to identify combinations of gene expression levels capable of characterizing different types of lymphoma, and (3) to assemble collections of such combinations that if considered jointly are capable of accurately distinguishing different types of lymphoma. The central concept of LAD is a pattern or combinatorial biomarker, a concept that resembles a rule as used in decision tree methods. LAD is able to exhaustively generate the collection of all those patterns which satisfy certain quality constraints, through a systematic combinatorial process guided by clear optimization criteria. Then, based on a set covering approach, LAD aggregates the collection of patterns into classification models. In addition, LAD is able to use the information provided by large collections of patterns in order to extract subsets of variables, which collectively are able to distinguish between different types of disease. For the differential diagnosis of DLBCL versus FL, a model based on eight significant genes is constructed and shown to have a sensitivity of 94.7% and a specificity of 100% on the test set. For the prognosis of good versus poor outcome among the DLBCL patients, a model is constructed on another set consisting also of eight significant genes, and shown to have a sensitivity of 87.5% and a specificity of 90% on the test set. The genes selected by LAD also work well as a basis for other kinds of statistical

  14. Multi-compartment linear noise approximation

    International Nuclear Information System (INIS)

    Challenger, Joseph D; McKane, Alan J; Pahle, Jürgen

    2012-01-01

    The ability to quantify the stochastic fluctuations present in biochemical and other systems is becoming increasing important. Analytical descriptions of these fluctuations are attractive, as stochastic simulations are computationally expensive. Building on previous work, a linear noise approximation is developed for biochemical models with many compartments, for example cells. The procedure is then implemented in the software package COPASI. This technique is illustrated with two simple examples and is then applied to a more realistic biochemical model. Expressions for the noise, given in the form of covariance matrices, are presented. (paper)

  15. [Intraabdominal hypertension and abdominal compartment syndrome

    DEFF Research Database (Denmark)

    Sonne, M.; Hilligsø, Jens Georg

    2008-01-01

    Intraabdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are rare conditions with high mortality. IAH is an intraabdominal pressure (IAP) above 12 mmHg and ACS an IAP above 20 mmHg with evidence of organ dysfunction. IAP is measured indirectly via the bladder or stomach. Various...... medical and surgical conditions increase the intraabdominal volume. When the content exceeds the compliance of the abdominal wall, the IAP rises. Increased IAP affects the functioning of the brain, lungs, circulation, kidneys, and bowel. The treatment of ACS is a reduction of IAP Udgivelsesdato: 2008/2/11...

  16. Phosphodiesterase profile of human B lymphocytes from normal and atopic donors and the effects of PDE inhibition on B cell proliferation

    Science.gov (United States)

    Gantner, Florian; Götz, Christine; Gekeler, Volker; Schudt, Christian; Wendel, Albrecht; Hatzelmann, Armin

    1998-01-01

    CD19+ B lymphocytes were purified from the peripheral blood of normal and atopic subjects to analyse and compare the phosphodiesterase (PDE) activity profile, PDE mRNA expression and the importance of PDE activity for the regulation of B cell function.The majority of cyclic AMP hydrolyzing activity of human B cells was cytosolic PDE4, followed by cytosolic PDE7-like activity; marginal PDE3 activity was found only in the particulate B cell fraction. PDE1, PDE2 and PDE5 activities were not detected.By cDNA-PCR analysis mRNA of the PDE4 subtypes A, B (splice variant PDE4B2) and D were detected. In addition, a weak signal for PDE3A was found.No differences in PDE activities or mRNA expression of PDE subtypes were found in B cells from either normal or atopic subjects.Stimulation of B lymphocytes with the polyclonal stimulus lipopolysaccharide (LPS) induced a proliferative response in a time- and concentration-dependent manner, which was increased in the presence of interleukin-4 (IL-4). PDE4 inhibitors (rolipram, piclamilast) led to an increase in the cellular cyclic AMP concentration and to an augmentation of proliferation, whereas a PDE3 inhibitor (motapizone) was ineffective, which is in accordance with the PDE profile found. The proliferation enhancing effect of the PDE4 inhibitors was partly mimicked by the cyclic AMP analogues dibutyryl (db) cyclic AMP and 5,6-dichloro-1-β-D-ribofuranosylbenzimidazole-3′,5′-cyclic monophosphorothioate, Sp-isomer (dcl-cBIMPS), respectively. However, at concentrations exceeding 100 μM db-cyclic AMP suppressed B lymphocyte proliferation, probably as a result of cytotoxicity. Prostaglandin E2 (PGE2, 1 μM) and forskolin (10 μM) did not affect B cell proliferation, even when given in combination with rolipram.Inhibition of protein kinase A (PKA) by differentially acting selective inhibitors (KT 5720, Rp-8-Br-cyclic AMPS) decreased the proliferative response of control cells and reversed the proliferation enhancing effects

  17. The FOX and the mutants in mature human B cells and DLBCL: The role of FOXP1 in mature human B cell biology and lymphomagenesis & prevalence of oncogenic MyD88 and CD79B mutations in diffuse large B cell lymphoma

    NARCIS (Netherlands)

    van Keimpema, M.

    2015-01-01

    The transcription factor FOXP1 is prominently expressed in mature B cells and is a potential oncogene in B cell non-Hodgkin lymphomas; however, the functions of FOXP1 in mature B cells and B cell lymphomagenesis have not yet been fully explored. In the first part of this thesis, the roles of FOXP1

  18. Peripheral Neuropathy and Agent Orange

    Science.gov (United States)

    ... Enter ZIP code here Enter ZIP code here Peripheral Neuropathy and Agent Orange VA presumes Veterans' early-onset ... 10 percent disabling by VA's rating regulations. About peripheral neuropathy Peripheral neuropathy is a condition of the peripheral ...

  19. Impaired B cell development in the absence of Krüppel-like factor 3.

    Science.gov (United States)

    Vu, Thi Thanh; Gatto, Dominique; Turner, Vivian; Funnell, Alister P W; Mak, Ka Sin; Norton, Laura J; Kaplan, Warren; Cowley, Mark J; Agenès, Fabien; Kirberg, Jörg; Brink, Robert; Pearson, Richard C M; Crossley, Merlin

    2011-11-15

    Krüppel-like factor 3 (Klf3) is a member of the Klf family of transcription factors. Klfs are widely expressed and have diverse roles in development and differentiation. In this study, we examine the function of Klf3 in B cell development by studying B lymphopoiesis in a Klf3 knockout mouse model. We show that B cell differentiation is significantly impaired in the bone marrow, spleen, and peritoneal cavity of Klf3 null mice and confirm that the defects are cell autonomous. In the bone marrow, there is a reduction in immature B cells, whereas recirculating mature cells are noticeably increased. Immunohistology of the spleen reveals a poorly structured marginal zone (MZ) that may in part be caused by deregulation of adhesion molecules on MZ B cells. In the peritoneal cavity, there are significant defects in B1 B cell development. We also report that the loss of Klf3 in MZ B cells is associated with reduced BCR signaling strength and an impaired ability to respond to LPS stimulation. Finally, we show increased expression of a number of Klf genes in Klf3 null B cells, suggesting that a Klf regulatory network may exist in B cells.

  20. Function of Bruton's tyrosine kinase during B cell development is partially independent of its catalytic activity

    NARCIS (Netherlands)

    S. Middendorp; G.M. Dingjan (Gemma); A. Maas (Alex); K. Dahlenborg; R.W. Hendriks (Rudi)

    2003-01-01

    textabstractThe Tec family member Bruton's tyrosine kinase (Btk) is a cytoplasmic protein tyrosine kinase that transduces signals from the pre-B and B cell receptor (BCR). Btk is involved in pre-B cell maturation by regulating IL-7 responsiveness, cell surface phenotype changes,

  1. EBV-positive diffuse large B-cell lymphoma of the elderly

    NARCIS (Netherlands)

    C.Y. Ok (Chi Young); T.G. Papathomas (Thomas); L.J. Medeiros (L. Jeffrey); K.H. Young (Ken)

    2013-01-01

    textabstractEpstein-Barr virus (EBV) positive diffuse large B-cell lymphoma (DLBCL) of the elderly, initially described in 2003, is a provisional entity in the 2008World Health Organization classification system and is defined as an EBV-positive monoclonal large B-cell proliferation that occurs in

  2. Docking of B-cell epitope antigen to specific hepatitis B antibody

    Indian Academy of Sciences (India)

    The interaction of pres1 region of hepatitis B virus B-cell epitope antigen with specific hepatitis B neutralizing monoclonal antibody was examined by docking study. We modelled the 3D complex structure of B-cell epitope antigen residues CTTPAQGNSMFPSCCCTKPTDGNCY by homology modelling and docked it with the ...

  3. Evaluating the B-cell density with various activation functions using White Noise Path Integral Approach

    Science.gov (United States)

    Aban, C. J. G.; Bacolod, R. O.; Confesor, M. N. P.

    2015-06-01

    A The White Noise Path Integral Approach is used in evaluating the B-cell density or the number of B-cell per unit volume for a basic type of immune system response based on the modeling done by Perelson and Wiegel. From the scaling principles of Perelson [1], the B- cell density is obtained where antigens and antibodies mutates and activation function f(|S-SA|) is defined describing the interaction between a specific antigen and a B-cell. If the activation function f(|S-SA|) is held constant, the major form of the B-cell density evaluated using white noise analysis is similar to the form of the B-cell density obtained by Perelson and Wiegel using a differential approach.A piecewise linear functionis also used to describe the activation f(|S-SA|). If f(|S-SA|) is zero, the density decreases exponentially. If f(|S-SA|) = S-SA-SB, the B- cell density increases exponentially until it reaches a certain maximum value. For f(|S-SA|) = 2SA-SB-S, the behavior of B-cell density is oscillating and remains to be in small values.

  4. Changes in Circulating B Cell Subsets Associated with Aging and Acute SIV Infection in Rhesus Macaques.

    Science.gov (United States)

    Chang, W L William; Gonzalez, Denise F; Kieu, Hung T; Castillo, Luis D; Messaoudi, Ilhem; Shen, Xiaoying; Tomaras, Georgia D; Shacklett, Barbara L; Barry, Peter A; Sparger, Ellen E

    2017-01-01

    Aging and certain viral infections can negatively impact humoral responses in humans. To further develop the nonhuman primate (NHP) model for investigating B cell dynamics in human aging and infectious disease, a flow cytometric panel was developed to characterize circulating rhesus B cell subsets. Significant differences between human and macaque B cells included the proportions of cells within IgD+ and switched memory populations and a prominent CD21-CD27+ unswitched memory population detected only in macaques. We then utilized the expanded panel to analyze B cell alterations associated with aging and acute simian immunodeficiency virus (SIV) infection in the NHP model. In the aging study, distinct patterns of B cell subset frequencies were observed for macaques aged one to five years compared to those between ages 5 and 30 years. In the SIV infection study, B cell frequencies and absolute number were dramatically reduced following acute infection, but recovered within four weeks of infection. Thereafter, the frequencies of activated memory B cells progressively increased; these were significantly correlated with the magnitude of SIV-specific IgG responses, and coincided with impaired maturation of anti-SIV antibody avidity, as previously reported for HIV-1 infection. These observations further validate the NHP model for investigation of mechanisms responsible for B cells alterations associated with immunosenescence and infectious disease.

  5. B-cell lymphoma in a dog with ehrlichiosis (Ehrlichia canis) and systemic histoplasmosis (Histoplasma capsulatum).

    Science.gov (United States)

    Brunker, Jill D; Hoover, John P

    2007-03-01

    A mixed breed dog treated for ehrlichiosis and systemic histoplasmosis developed a refractory thrombocytopenia. When an abdominal mass was detected, exploratory laparotomy and biopsies confirmed lymphoma, which on immunohistochemical stains was determined to be of B-cell origin. Conceivably, the B-cell lymphoma in this dog was associated with chronic inflammation from ehrlichiosis, histoplasmosis, or both.

  6. The VP7 Outer Capsid Protein of Rotavirus Induces Polyclonal B-Cell Activation

    Science.gov (United States)

    Blutt, Sarah E.; Crawford, Sue E.; Warfield, Kelly L.; Lewis, Dorothy E.; Estes, Mary K.; Conner, Margaret E.

    2004-01-01

    The early response to a homologous rotavirus infection in mice includes a T-cell-independent increase in the number of activated B lymphocytes in the Peyer's patches. The mechanism of this activation has not been previously determined. Since rotavirus has a repetitively arranged triple-layered capsid and repetitively arranged antigens can induce activation of B cells, one or more of the capsid proteins could be responsible for the initial activation of B cells during infection. To address this question, we assessed the ability of rotavirus and virus-like particles to induce B-cell activation in vivo and in vitro. Using infectious rotavirus, inactivated rotavirus, noninfectious but replication-competent virus, and virus-like particles, we determined that neither infectivity nor RNA was necessary for B-cell activation but the presence of the rotavirus outer capsid protein, VP7, was sufficient for murine B-cell activation. Preincubation of the virus with neutralizing VP7 antibodies inhibited B-cell activation. Polymyxin B treatment and boiling of the virus preparation were performed, which ruled out possible lipopolysaccharide contamination as the source of activation and confirmed that the structural conformation of VP7 is important for B-cell activation. These findings indicate that the structure and conformation of the outer capsid protein, VP7, initiate intestinal B-cell activation during rotavirus infection. PMID:15194774

  7. Toll-like receptors in the pathogenesis of human B cell malignancies

    NARCIS (Netherlands)

    Isaza-Correa, Johana M.; Liang, Zheng; van den Berg, Anke; Diepstra, Arjan; Visser, Lydia

    2014-01-01

    Toll-like receptors (TLRs) are important players in B-cell activation, maturation and memory and may be involved in the pathogenesis of B-cell lymphomas. Accumulating studies show differential expression in this heterogeneous group of cancers. Stimulation with TLR specific ligands, or agonists of

  8. Differentiation of purified malignant B cells induced by PMA or by activated normal T cells

    NARCIS (Netherlands)

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

    1993-01-01

    We studied the in vitro differentiation (immunoglobulin production) of purified malignant B cells of 21 patients with different B-cell malignancies, including chronic lymphocytic leukemia (CLL), prolymphocytic leukemia (PLL), hairy cell leukemia (HCL) and non-Hodgkin lymphoma (NHL). Direct

  9. DEFECTS IN INSULIN-SECRETION IN NIDDM - B-CELL GLUCOSE INSENSITIVITY OR GLUCOSE TOXICITY

    NARCIS (Netherlands)

    VANHAEFTEN, TW

    In NIDDM, first-phase insulin release to glucose is (almost) absent. However, in contrast to older studies which suggested that in NIDDM the B-cell is ''blind'' for glucose, recent evidence indicates that the B-cell is not insensitive for glucose as far as second phase release is concerned. This

  10. Excessive amounts of mu heavy chain block B-cell development.

    Science.gov (United States)

    Zhu, Lingqiao; Chang, Cheong-Hee; Dunnick, Wesley

    2011-09-01

    Antigen-independent B-cell development occurs in several stages that depend on the expression of Ig heavy and light chain. We identified a line of mice that lacked mature B cells in the spleen. This mouse line carried approximately 11 copies of a transgene of the murine heavy chain constant region locus, and B-lineage cells expressed excessive amounts of the intracellular μ heavy chain. B-cell development failed in the bone marrow at the pro/pre B-cell transition, and examination of other lines with various copy numbers of the same transgene suggested that deficiencies in B-cell development increased with increased transgene copy number. Expression of a transgenic (Tg) light chain along with the Tg μ heavy chain led to minimal rescue of B-cell development in the bone marrow and B cells in the spleen. There are several potential mechanisms for the death of pro/pre B cells as a consequence of excess heavy chain expression.

  11. Microfluidic squeezing for intracellular antigen loading in polyclonal B-cells as cellular vaccines

    Science.gov (United States)

    Lee Szeto, Gregory; van Egeren, Debra; Worku, Hermoon; Sharei, Armon; Alejandro, Brian; Park, Clara; Frew, Kirubel; Brefo, Mavis; Mao, Shirley; Heimann, Megan; Langer, Robert; Jensen, Klavs; Irvine, Darrell J.

    2015-05-01

    B-cells are promising candidate autologous antigen-presenting cells (APCs) to prime antigen-specific T-cells both in vitro and in vivo. However to date, a significant barrier to utilizing B-cells as APCs is their low capacity for non-specific antigen uptake compared to “professional” APCs such as dendritic cells. Here we utilize a microfluidic device that employs many parallel channels to pass single cells through narrow constrictions in high throughput. This microscale “cell squeezing” process creates transient pores in the plasma membrane, enabling intracellular delivery of whole proteins from the surrounding medium into B-cells via mechano-poration. We demonstrate that both resting and activated B-cells process and present antigens delivered via mechano-poration exclusively to antigen-specific CD8+T-cells, and not CD4+T-cells. Squeezed B-cells primed and expanded large numbers of effector CD8+T-cells in vitro that produced effector cytokines critical to cytolytic function, including granzyme B and interferon-γ. Finally, antigen-loaded B-cells were also able to prime antigen-specific CD8+T-cells in vivo when adoptively transferred into mice. Altogether, these data demonstrate crucial proof-of-concept for mechano-poration as an enabling technology for B-cell antigen loading, priming of antigen-specific CD8+T-cells, and decoupling of antigen uptake from B-cell activation.

  12. Secondary immunization generates clonally related antigen-specific plasma cells and memory B cells.

    Science.gov (United States)

    Frölich, Daniela; Giesecke, Claudia; Mei, Henrik E; Reiter, Karin; Daridon, Capucine; Lipsky, Peter E; Dörner, Thomas

    2010-09-01

    Rechallenge with T cell-dependent Ags induces memory B cells to re-enter germinal centers (GCs) and undergo further expansion and differentiation into plasma cells (PCs) and secondary memory B cells. It is currently not known whether the expanded population of memory B cells and PCs generated in secondary GCs are clonally related, nor has the extent of proliferation and somatic hypermutation of their precursors been delineated. In this study, after secondary tetanus toxoid (TT) immunization, TT-specific PCs increased 17- to 80-fold on days 6-7, whereas TT-specific memory B cells peaked (delayed) on day 14 with a 2- to 22-fold increase. Molecular analyses of V(H)DJ(H) rearrangements of individual cells revealed no major differences of gene usage and CDR3 length between TT-specific PCs and memory B cells, and both contained extensive evidence of somatic hypermutation with a pattern consistent with GC reactions. This analysis identified clonally related TT-specific memory B cells and PCs. Within clusters of clonally related cells, sequences shared a number of mutations but also could contain additional base pair changes. The data indicate that although following secondary immunization PCs can derive from memory B cells without further somatic hypermutation, in some circumstances, likely within GC reactions, asymmetric mutation can occur. These results suggest that after the fate decision to differentiate into secondary memory B cells or PCs, some committed precursors continue to proliferate and mutate their V(H) genes.

  13. Cutaneous B-cell lymphoma : classification, prognostic factors and management recommendations

    NARCIS (Netherlands)

    Senff, Nancy Johanna

    2009-01-01

    The term primary cutaneous B-cell lymphomas refers to a heterogeneous group of B-cell non-Hodgkin lymphomas, that present in the skin without evidence of extracutaneous disease at the time of diagnosis. In recent years, there has been considerable debate regarding the classification and terminology

  14. A multi-scale model for correlation in B cell VDJ usage of zebrafish

    International Nuclear Information System (INIS)

    Pan, Keyao; Deem, Michael W

    2011-01-01

    The zebrafish (Danio rerio) is one of the model animals used for the study of immunology because the dynamics in the adaptive immune system of zebrafish are similar to that in higher animals. In this work, we built a multi-scale model to simulate the dynamics of B cells in the primary and secondary immune responses of zebrafish. We use this model to explain the reported correlation between VDJ usage of B cell repertoires in individual zebrafish. We use a delay ordinary differential equation (ODE) system to model the immune responses in the 6-month lifespan of a zebrafish. This mean field theory gives the number of high-affinity B cells as a function of time during an infection. The sequences of those B cells are then taken from a distribution calculated by a 'microscopic' random energy model. This generalized NK model shows that mature B cells specific to one antigen largely possess a single VDJ recombination. The model allows first-principle calculation of the probability, p, that two zebrafish responding to the same antigen will select the same VDJ recombination. This probability p increases with the B cell population size and the B cell selection intensity. The probability p decreases with the B cell hypermutation rate. The multi-scale model predicts correlations in the immune system of the zebrafish that are highly similar to that from experiment

  15. A multi-scale model for correlation in B cell VDJ usage of zebrafish

    Science.gov (United States)

    Pan, Keyao; Deem, Michael W.

    2011-10-01

    The zebrafish (Danio rerio) is one of the model animals used for the study of immunology because the dynamics in the adaptive immune system of zebrafish are similar to that in higher animals. In this work, we built a multi-scale model to simulate the dynamics of B cells in the primary and secondary immune responses of zebrafish. We use this model to explain the reported correlation between VDJ usage of B cell repertoires in individual zebrafish. We use a delay ordinary differential equation (ODE) system to model the immune responses in the 6-month lifespan of a zebrafish. This mean field theory gives the number of high-affinity B cells as a function of time during an infection. The sequences of those B cells are then taken from a distribution calculated by a 'microscopic' random energy model. This generalized NK model shows that mature B cells specific to one antigen largely possess a single VDJ recombination. The model allows first-principle calculation of the probability, p, that two zebrafish responding to the same antigen will select the same VDJ recombination. This probability p increases with the B cell population size and the B cell selection intensity. The probability p decreases with the B cell hypermutation rate. The multi-scale model predicts correlations in the immune system of the zebrafish that are highly similar to that from experiment.

  16. Rituximab in the treatment of primary cutaneous B-cell lymphoma: a review.

    Science.gov (United States)

    Fernández-Guarino, M; Ortiz-Romero, P L; Fernández-Misa, R; Montalbán, C

    2014-06-01

    Rituximab is a chimeric mouse-human antibody that targets the CD20 antigen, which is found in both normal and neoplastic B cells. In recent years, it has been increasingly used to treat cutaneous B-cell lymphoma and is now considered an alternative to classic treatment (radiotherapy and surgery) of 2 types of indolent lymphoma, namely, primary cutaneous follicle center lymphoma and primary cutaneous marginal zone B-cell lymphoma. Rituximab is also administered as an alternative to polychemotherapy in the treatment of primary cutaneous large B-cell lymphoma, leg type. Its use as an alternative drug led to it being administered intralesionally, with beneficial effects. In the present article, we review the literature published on the use of rituximab to treat primary cutaneous B-cell lymphoma. Copyright © 2012 Elsevier España, S.L. and AEDV. All rights reserved.

  17. Preparation of antisera specific for human B cells by immunization of rabbits with immune complexes

    International Nuclear Information System (INIS)

    Welsh, K.I.; Turner, M.J.

    1976-01-01

    Three rabbit antisera are described which are specific without absorption (titer 1:100) for separated human B cells, as measured by complement and non-complement fixing assays. The method of production of these sera involved injections of rabbits with precipitin lines formed between 10μ1 of three separate detergent solubilized membrane preparations and 4μ1 aliquots of rabbit antisera to human B cells. In addition to being B cell specific, the three sera block the MLC reaction, inhibit aggregated IgG binding to B cells, and show differential degrees of B cell lysis when tested on a panel of separated B and T cells. These and other properties suggest that the target specificities of the antibodies are the human equivalent of the murine Ia antigens. (author)

  18. B cells are multifunctional players in multiple sclerosis pathogenesis: insights from therapeutic interventions

    Directory of Open Access Journals (Sweden)

    Nele eClaes

    2015-12-01

    Full Text Available Multiple sclerosis (MS is a severe disease of the central nervous system (CNS characterized by autoimmune inflammation and neurodegeneration. Historically, damage to the CNS was thought to be mediated predominantly by activated pro-inflammatory T cells. B cell involvement in the pathogenesis of MS was solely attributed to autoantibody production. The first clues for the involvement of antibody-independent B cell functions in MS pathology came from positive results in clinical trials of the B cell depleting treatment rituximab in patients with relapsing-remitting (RR MS. The survival of antibody-secreting plasma cells and decrease in T cell numbers indicated the importance of other B cell functions in MS such as antigen presentation, costimulation and cytokine production. Rituximab provided us with an example of how clinical trials can lead to new research opportunities concerning B cell biology. Moreover, analysis of the antibody-independent B cell functions in MS has gained interest since these trials. Limited information is present on the effects of current immunomodulatory therapies on B cell functions, although effects of both first-line (interferon, glatiramer acetate, dimethyl fumarate and teriflunomide, second-line (fingolimod, natalizumab and even third-line (monoclonal antibody therapies treatments on B cell subtype distribution, expression of functional surface markers and secretion of different cytokines by B cells have been studied to some extent. In this review, we summarize the effects of different MS related treatments on B cell functions that have been described up to now in order to find new research opportunities and contribute to the understanding of the pathogenesis of MS.

  19. B cell activation by outer membrane vesicles--a novel virulence mechanism.

    Directory of Open Access Journals (Sweden)

    Maria Laura A Perez Vidakovics

    2010-01-01

    Full Text Available Secretion of outer membrane vesicles (OMV is an intriguing phenomenon of Gram-negative bacteria and has been suggested to play a role as virulence factors. The respiratory pathogens Moraxella catarrhalis reside in tonsils adjacent to B cells, and we have previously shown that M. catarrhalis induce a T cell independent B cell response by the immunoglobulin (Ig D-binding superantigen MID. Here we demonstrate that Moraxella are endocytosed and killed by human tonsillar B cells, whereas OMV have the potential to interact and activate B cells leading to bacterial rescue. The B cell response induced by OMV begins with IgD B cell receptor (BCR clustering and Ca(2+ mobilization followed by BCR internalization. In addition to IgD BCR, TLR9 and TLR2 were found to colocalize in lipid raft motifs after exposure to OMV. Two components of the OMV, i.e., MID and unmethylated CpG-DNA motifs, were found to be critical for B cell activation. OMV containing MID bound to and activated tonsillar CD19(+ IgD(+ lymphocytes resulting in IL-6 and IgM production in addition to increased surface marker density (HLA-DR, CD45, CD64, and CD86, whereas MID-deficient OMV failed to induce B cell activation. DNA associated with OMV induced full B cell activation by signaling through TLR9. Importantly, this concept was verified in vivo, as OMV equipped with MID and DNA were found in a 9-year old patient suffering from Moraxella sinusitis. In conclusion, Moraxella avoid direct interaction with host B cells by redirecting the adaptive humoral immune response using its superantigen-bearing OMV as decoys.

  20. Diagnostic value of immunoglobulin κ light chain gene rearrangement analysis in B-cell lymphomas.

    Science.gov (United States)

    Kokovic, Ira; Jezersek Novakovic, Barbara; Novakovic, Srdjan

    2015-03-01

    Analysis of the immunoglobulin κ light chain (IGK) gene is an alternative method for B-cell clonality assessment in the diagnosis of mature B-cell proliferations in which the detection of clonal immunoglobulin heavy chain (IGH) gene rearrangements fails. The aim of the present study was to evaluate the added value of standardized BIOMED-2 assay for the detection of clonal IGK gene rearrangements in the diagnostic setting of suspected B-cell lymphomas. With this purpose, 92 specimens from 80 patients with the final diagnosis of mature B-cell lymphoma (37 specimens), mature T-cell lymphoma (26 specimens) and reactive lymphoid proliferation (29 specimens) were analyzed for B-cell clonality. B-cell clonality analysis was performed using the BIOMED-2 IGH and IGK gene clonality assays. The determined sensitivity of the IGK assay was 67.6%, while the determined sensitivity of the IGH assay was 75.7%. The sensitivity of combined IGH+IGK assay was 81.1%. The determined specificity of the IGK assay was 96.2% in the group of T-cell lymphomas and 96.6% in the group of reactive lesions. The determined specificity of the IGH assay was 84.6% in the group of lymphomas and 86.2% in the group of reactive lesions. The comparison of GeneScan (GS) and heteroduplex pretreatment-polyacrylamide gel electrophoresis (HD-PAGE) methods for the analysis of IGK gene rearrangements showed a higher efficacy of GS analysis in a series of 27 B-cell lymphomas analyzed by both methods. In the present study, we demonstrated that by applying the combined IGH+IGK clonality assay the overall detection rate of B-cell clonality was increased by 5.4%. Thus, we confirmed the added value of the standardized BIOMED-2 IGK assay for assessment of B-cell clonality in suspected B-cell lymphomas with inconclusive clinical and cyto/histological diagnosis.

  1. B cells promote obesity-associated periodontitis and oral pathogen-associated inflammation.

    Science.gov (United States)

    Zhu, Min; Belkina, Anna C; DeFuria, Jason; Carr, Jordan D; Van Dyke, Thomas E; Gyurko, Robert; Nikolajczyk, Barbara S

    2014-08-01

    Individuals with T2D and PD suffer significantly from the ability of one disease to intensify the other. Disease-associated inflammation is one mechanism thought to fuel this pathogenic feed-forward loop. Several lines of evidence indicate that proinflammatory B cells promote T2D and PD; thus, B cells are top candidates for a cell type that predisposes PD in T2D. To test directly the role of B cells in T2D-associated PD, we compared outcomes from oral Porphyromonas gingivalis challenge of lean WT or B cell-null mice with outcomes from mice that were obese and insulin-resistant before challenge. Obese WT mice responded to oral P. gingivalis challenge with significant periodontal bone loss, whereas obese B cell-null mice were protected completely from PD. By contrast, lean WT and B cell-null mice suffer similar periodontal bone loss in response to oral pathogen. B cells from obese/insulin-resistant hosts also support oral osteoclastogenesis and both oral and systemic production of inflammatory cytokines, including pro-osteoclastogenic TNF-α and MIP-2, an ortholog of human IL-8. B cells furthermore impact AT inflammation in obese, P. gingivalis-infected hosts. Taken together, these data show that fundamentally different mechanisms regulate PD in lean and obese hosts, with B cells able to promote PD only if the hosts are "primed" by obesity. These results justify more intense analysis of obesity-associated changes in B cells that predispose PD in human T2D. © 2014 Society for Leukocyte Biology.

  2. Differential Effects of Tacrolimus versus Sirolimus on the Proliferation, Activation and Differentiation of Human B Cells.

    Directory of Open Access Journals (Sweden)

    Opas Traitanon

    Full Text Available The direct effect of immunosuppressive drugs calcineurin inhibitor (Tacrolimus, TAC and mTOR inhibitor (Sirolimus, SRL on B cell activation, differentiation and proliferation is not well documented. Purified human B cells from healthy volunteers were stimulated through the B Cell Receptor with Anti-IgM + anti-CD40 + IL21 in the absence / presence of TAC or SRL. A variety of parameters of B cell activity including activation, differentiation, cytokine productions and proliferation were monitored by flow cytometry. SRL at clinically relevant concentrations (6 ng/ml profoundly inhibited CD19(+ B cell proliferation compared to controls whereas TAC at similar concentrations had a minimal effect. CD27(+ memory B cells were affected more by SRL than naïve CD27- B cells. SRL effectively blocked B cell differentiation into plasma cells (CD19(+CD138(+ and Blimp1(+/Pax5(low cells even at low dose (2 ng/ml, and totally eliminated them at 6 ng/ml. SRL decreased absolute B cell counts, but the residual responding cells acquired an activated phenotype (CD25(+/CD69(+ and increased the expression of HLA-DR. SRL-treated stimulated B cells on a per cell basis were able to enhance the proliferation of allogeneic CD4(+CD25(- T cells and induce a shift toward the Th1 phenotype. Thus, SRL and TAC have different effects on B lymphocytes. These data may provide insights into the clinical use of these two agents in recipients of solid organ transplants.

  3. Interaction of the B cell-specific transcriptional coactivator OCA-B and galectin-1 and a possible role in regulating BCR-mediated B cell proliferation.

    Science.gov (United States)

    Yu, Xin; Siegel, Rachael; Roeder, Robert G

    2006-06-02

    OCA-B is a B cell-specific transcriptional coactivator for OCT factors during the activation of immunoglobulin genes. In addition, OCA-B is crucial for B cell activation and germinal center formation. However, the molecular mechanisms for OCA-B function in these processes are not clear. Our previous studies documented two OCA-B isoforms and suggested a novel mechanism for the function of the myristoylated, membrane-bound form of OCA-B/p35 as a signaling molecule. Here, we report the identification of galectin-1, and related galectins, as a novel OCA-B-interacting protein. The interaction of OCA-B and galectin-1 can be detected both in vivo and in vitro. The galectin-1 binding domain in OCA-B has been localized to the N terminus of OCA-B. In B cells lacking OCA-B expression, increased galectin-1 expression, secretion, and cell surface association are observed. Consistent with these observations, and a reported inhibitory interaction of galectin-1 with CD45, the phosphatase activity of CD45 is reduced modestly, but significantly, in OCA-B-deficient B cells. Finally, galectin-1 is shown to negatively regulate B cell proliferation and tyrosine phosphorylation upon BCR stimulation. Together, these results raise the possibility that OCA-B may regulate BCR signaling through an association with galectin-1.

  4. Soluble suppressor supernatants elaborated by concanavalin A-activated human mononuclear cells. Characterization of a soluble suppressor of B cell immunoglobulin production

    International Nuclear Information System (INIS)

    Fleisher, T.A.; Greene, W.C.; Blaese, R.M.; Waldmann, T.A.

    1981-01-01

    Human peripheral blood mononuclear cells (PBMC) activated with the mitogenic lectin concanavalin A (Con A) elaborate a soluble immune suppressor supernatant (SISS) that contains at least 2 distinct suppressor factors. One of these, SISS-B, inhibits polyclonal B cell immunoglobulin production, whereas the other, SISS-T, suppresses T cell proliferation to both mitogens and antigens. The latter mediator is discussed in the companion paper. Characteristics of the human soluble suppressor of B cell immunoglobulin production (SISS-B) include: 1) inhibition by a noncytotoxic mechanism, 2) loss of activity in the presence of the monosaccharide L-rhamnose, 3) appearance within 8 to 16 hr after the addition of Con A, 4) elaboration by cells irradiated with 500 or 2000 rads, 5) production by highly purified T cells, 6) stability at pH 2.5 but instability at 56/sup o/C, and 7) m.w. of 60 to 80,000. These data indicate that after Con A activation, selected T cells not only become potent suppressor cells, but also generate a soluble saccharide-specific factor(s) that inhibits polyclonal immunoglobulin production by human B cells

  5. The Tol2 transposon system mediates the genetic engineering of T-cells with CD19-specific chimeric antigen receptors for B-cell malignancies.

    Science.gov (United States)

    Tsukahara, T; Iwase, N; Kawakami, K; Iwasaki, M; Yamamoto, C; Ohmine, K; Uchibori, R; Teruya, T; Ido, H; Saga, Y; Urabe, M; Mizukami, H; Kume, A; Nakamura, M; Brentjens, R; Ozawa, K

    2015-02-01

    Engineered T-cell therapy using a CD19-specific chimeric antigen receptor (CD19-CAR) is a promising strategy for the treatment of advanced B-cell malignancies. Gene transfer of CARs to T-cells has widely relied on retroviral vectors, but transposon-based gene transfer has recently emerged as a suitable nonviral method to mediate stable transgene expression. The advantages of transposon vectors compared with viral vectors include their simplicity and cost-effectiveness. We used the Tol2 transposon system to stably transfer CD19-CAR into human T-cells. Normal human peripheral blood lymphocytes were co-nucleofected with the Tol2 transposon donor plasmid carrying CD19-CAR and the transposase expression plasmid and were selectively propagated on NIH3T3 cells expressing human CD19. Expanded CD3(+) T-cells with stable and high-level transgene expression (~95%) produced interferon-γ upon stimulation with CD19 and specifically lysed Raji cells, a CD19(+) human B-cell lymphoma cell line. Adoptive transfer of these T-cells suppressed tumor progression in Raji tumor-bearing Rag2(-/-)γc(-/-) immunodeficient mice compared with control mice. These results demonstrate that the Tol2 transposon system could be used to express CD19-CAR in genetically engineered T-cells for the treatment of refractory B-cell malignancies.

  6. Activation of the PI3K/AKT pathway by microRNA-22 results in CLL B-cell proliferation.

    Science.gov (United States)

    Palacios, F; Abreu, C; Prieto, D; Morande, P; Ruiz, S; Fernández-Calero, T; Naya, H; Libisch, G; Robello, C; Landoni, A I; Gabus, R; Dighiero, G; Oppezzo, P

    2015-01-01

    Chronic lymphocytic leukemia (CLL) is characterized by accumulation of clonal B cells arrested in G0/G1 stages that coexist, in different proportions, with proliferative B cells. Understanding the crosstalk between the proliferative subsets and their milieu could provide clues on CLL biology. We previously identified one of these subpopulations in the peripheral blood from unmutated patients that appears to be a hallmark of a progressive disease. Aiming to characterize the molecular mechanism underlying this proliferative behavior, we performed gene expression analysis comparing the global mRNA and microRNA expression of this leukemic subpopulation, and compared it with their quiescent counterparts. Our results suggest that proliferation of this fraction depend on microRNA-22 overexpression that induces phosphatase and tensin homolog downregulation and phosphoinositide 3-kinase (PI3K)/AKT pathway activation. Transfection experiments demonstrated that miR-22 overexpression in CLL B cells switches on PI3K/AKT, leading to downregulation of p27(-Kip1) and overexpression of Survivin and Ki-67 proteins. We also demonstrated that this pathway could be triggered by microenvironment signals like CD40 ligand/interleukin-4 and, more importantly, that this regulatory loop is also present in lymph nodes from progressive unmutated patients. Altogether, these results underline the key role of PI3K/AKT pathway in the generation of the CLL proliferative pool and provide additional rationale for the usage of PI3K inhibitors.

  7. Specific Antibody Production by Blood B Cells is Retained in Late Stage Drug-naïve HIV-infected Africans

    Directory of Open Access Journals (Sweden)

    Lydie Béniguel

    2004-01-01

    Full Text Available Unseparated peripheral blood mononuclear cells (PBMCs obtained from drug-naïve African individuals living in a context of multi-infections and presenting with high viral load (VL, were cultured in vitro and tested for their ability to produce antibodies (Abs reacting with HIV-1 antigens. Within these PBMCs, circulating B cells were differentiated in vitro and produced IgG Abs against not only ENV, but also GAG and POL proteins. Under similar experimental conditions, HAART treated patients produced Abs to ENV proteins only. The in vitro antibody production by drug-naïve individuals' PBMCs depended on exogenous cytokines (IL-2 and IL-10 but neither on the re-stimulation of reactive cells in cultures by purified HIV-1-gp 160 antigen nor on the re-engagement of CD40 surface molecules. Further, it was not abrogated by the addition of various monoclonal Abs (mAbs to co-stimulatory molecules. This suggests that the in vitro antibody production by drug-naïve individuals' PBMCs resulted from the maturation of already envelope and core antigen-primed, differentiated B cells, presumably pre-plasma cells, which are not known to circulate at homeostasy. As in vitro produced Abs retained the capacity of binding antigen and forming complexes, this study provides pre-clinical support for functional humoral responses despite major HIV- and other tropical pathogen-induced B cell perturbations.

  8. FOXP1 suppresses immune response signatures and MHC class II expression in activated B-cell-like diffuse large B-cell lymphomas

    DEFF Research Database (Denmark)

    Brown, P J; Wong, K K; Felce, S L

    2016-01-01

    The FOXP1 (forkhead box P1) transcription factor is a marker of poor prognosis in diffuse large B-cell lymphoma (DLBCL). Here microarray analysis of FOXP1-silenced DLBCL cell lines identified differential regulation of immune response signatures and major histocompatibility complex class II (MHC II......) genes as some of the most significant differences between germinal center B-cell (GCB)-like DLBCL with full-length FOXP1 protein expression versus activated B-cell (ABC)-like DLBCL expressing predominantly short FOXP1 isoforms. In an independent primary DLBCL microarray data set, multiple MHC II genes......, including human leukocyte antigen DR alpha chain (HLA-DRA), were inversely correlated with FOXP1 transcript expression (PABC-DLBCL cells led to increased cell-surface expression of HLA-DRA and CD74. In R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone...

  9. Arbuscules of vesicular-arbuscular mycorrhizal fungi inhabit an acidic compartment within plant roots.

    Science.gov (United States)

    Guttenberger, M

    2000-08-01

    The most widespread type of mycorrhiza is the so-called vesicular-arbuscular mycorrhiza. In this endomycorrhiza, fungal hyphae penetrate plant cell walls in the root cortex. There they form densely branched arbuscules. Fungus and plant plasma membrane are separated by a common interfacial apoplast. The pH of the compartment between the symbionts is of pivotal importance for nutrient transfer. Histochemical experiments were conducted to check for an acidic nature of the interface in the model system Glomus versiforme (Karst.) Berch-Allium porrum L. Two chemically different acidotropic dyes (neutral red and LysoSensor Green DND-189) stained the arbuscules intensely. The staining of arbuscules could be eliminated by addition of the protonophore carbonylcyanide m-chlorophenylhydrazone (CCCP) or treatments leading to membrane rupture. Therefore, the staining of the arbuscules was based on the ion-trap mechanism, which indicates acidic, membrane-bound compartments. Microscopic examination of stained arbuscules at high optical resolution revealed a peripheral accumulation of the dye. Since plasmolysis rapidly destained the arbuscules, it is concluded that the dyes accumulate in the arbuscular interface, indicating the highly acidic nature of this compartment. The findings are discussed with respect to their relevance for the nutrient transfer in mycorrhizas. In addition, evidence for a discontinuity in the arbuscular interface between the stem and the branches of the arbuscule is given.

  10. Analysis of Efficacy and Tolerability of Bruton Tyrosine Kinase Inhibitor Ibrutinib in Various B-cell Malignancies in the General Community: A Single-center Experience.

    Science.gov (United States)

    Ali, Naveed; Malik, Faizan; Jafri, Syed Imran Mustafa; Naglak, Mary; Sundermeyer, Mark; Pickens, Peter V

    2017-07-01

    Ibrutinib, an irreversible inhibitor of Bruton tyrosine kinase (BTK), is a novel drug that has shown significant efficacy and survival benefit for treatment of various B-cell malignancies. The primary objective of the present study was to investigate the efficacy of ibrutinib therapy in various B-cell malignancies in the general community. The secondary objectives included studying the adverse effects, ibrutinib-induced peripheral lymphocytosis, and effect on immunoglobulin levels. The present study was a retrospective observational cohort analysis conducted at Abington Jefferson Health. The clinical response was determined from the hematologist's assessment and evaluated independently using the response criteria for each B-cell malignancy. Adverse effects were graded according to the Common Terminology Criteria for Adverse Events, version 4.0. The Wilcoxon signed-rank test was used to compare immunoglobulin levels before and after ibrutinib. Forty five patients with B-cell malignancies and receiving ibrutinib therapy were eligible. The median age was 73 years (range, 49-96 years), and 84.4% of the patients had received ≥ 1 previous therapy. The best overall response rate of all cohorts combined was 63.8%. The greatest overall response rate was observed in patients with chronic lymphocytic leukemia or small lymphocytic lymphoma (76.1%), followed by those with Waldenström macroglobulinemia (75%). Of the 45 patients, 88.9% experienced adverse effects. Antiplatelet activity of ibrutinib was most commonly observed (30.5%). Of note, 5 patients (11%) developed new-onset atrial fibrillation after drug initiation. Peripheral lymphocytosis after drug initiation was observed in most patients, with a peak level at 1 month (median lymphocyte count, 2.7 × 10 3 cells/μL). Although the IgG levels at 3, 6, and 12 months had decreased (P = .01 for all) compared with the levels before ibrutinib, the IgA levels had not increased at 3, 6, 12, and 24 months (P = .6, P = .5

  11. Metabolic activity is necessary for activation of T suppressor cells by B cells

    International Nuclear Information System (INIS)

    Elkins, K.L.; Stashak, P.W.; Baker, P.J.

    1990-01-01

    Ag-primed B cells must express cell-surface IgM, but not IgD or Ia Ag, and must remain metabolically active, in order to activate suppressor T cells (Ts) specific for type III pneumococcal polysaccharide. Ag-primed B cells that were gamma-irradiated with 1000r, or less, retained the ability to activate Ts; however, Ag-primed B cells exposed to UV light were not able to do so. gamma-Irradiated and UV-treated Ag-primed B cells both expressed comparable levels of cell-surface IgM, and both localized to the spleen after in vivo transfer; neither could proliferate in vitro in response to mitogens. By contrast, gamma-irradiated primed B cells were still able to synthesize proteins, whereas UV-treated primed B cells could not. These findings suggest that in order for Ag-primed B cells to activate Ts, they must (a) express cell-associated IgM (sIgM) antibody bearing the idiotypic determinants of antibody specific for type III pneumococcal polysaccharide, and (b) be able to synthesize protein for either the continued expression of sIgM after cell transfer, or for the elaboration of another protein molecule that is also required for the activation of Ts; this molecule does not appear to be Ia Ag

  12. Bone marrow pre-B cells and the clonal anergy theory of immunologic tolerance.

    Science.gov (United States)

    Nossal, G J

    1987-03-01

    This review begins with a summary of a decade's research from the author's own laboratory which documents the fact that B lymphocytes can receive and store negative, down-regulatory signals from an encounter with antigen, and that the sensitivity to such negative signalling depends critically on maturational status, the most immature B cells being the most susceptible. The review then examines the relationship between these experimentally-induced models of immunologic tolerance, with the pre-B to B cell transition as the critical stage for examination, and the real-life phenomenon of self-tolerance. It makes the point that no repertoire-purging mechanism to ensure self-tolerance can afford to be too effective, for fear of purging too many useful cells, given the number and variability of self-antigens. The review then examines certain dilemmas posed by recent findings in cellular and molecular immunology. These include: 1) the preferential use of particular VH gene families by B cells at different stages of the differentiation process; 2) the apparent frequency of B lymphocytes with the potential for antiself-reactivity in the B cell repertoire; and 3) the existence of a new type of B cell, the Ly-1-positive B cell, with peculiar characteristics. These findings are considered within the particular contexts of pre-B-to-B cell transition and tolerance induction through clonal anergy mechanisms.

  13. Characterization of Antigen-Specific B Cells Using Nominal Antigen-Coated Flow-Beads

    Science.gov (United States)

    Akl, Ahmed; Lepetit, Maud; Crochette, Romain; Giral, Magali; Lepourry, Julie; Pallier, Annaick; Castagnet, Stéphanie; Dugast, Emilie; Guillot-Gueguen, Cécile; Jacq-Foucher, Marylène; Saulquin, Xavier; Cesbron, Anne; Laplaud, David; Nicot, Arnaud; Brouard, Sophie; Soulillou, Jean-Paul

    2013-01-01

    In order to characterize the reactivity of B cells against nominal antigens, a method based on the coupling of antigens onto the surface of fluorescent core polystyrene beads was developed. We first demonstrate that murine B cells with a human MOG-specific BCR are able to interact with MOG-coated beads and do not recognize beads coated with human albumin or pp65. B cells purified from human healthy volunteer blood or immunized individuals were tested for their ability to interact with various nominal antigens, including viral, vaccine, self and alloantigens, chosen for their usefulness in studying a variety of pathological processes. A substantial amount of B cells binding self-antigen MOG-coated beads can be detected in normal blood. Furthermore, greater frequencies of B cell against anti-Tetanic Toxin or anti-EBNA1 were observed in primed individuals. This method can reveal increased frequencies of anti-HLA committed B cells in patients with circulating anti-HLA antibodies compared to unsensitized patients and normal individuals. Of interest, those specific CD19 cells were preferentially identified within CD27−IgD+ (i-e naïve) subset. These observations suggest that a broad range of medical situations could benefit from a tool that allows the detection, the quantification and the characterization of antigen-specific blood B cells. PMID:24386360

  14. Surface receptor Toso controls B cell-mediated regulation of T cell immunity.

    Science.gov (United States)

    Yu, Jinbo; Duong, Vu Huy Hoang; Westphal, Katrin; Westphal, Andreas; Suwandi, Abdulhadi; Grassl, Guntram A; Brand, Korbinian; Chan, Andrew C; Föger, Niko; Lee, Kyeong-Hee

    2018-05-01

    The immune system is tightly controlled by regulatory processes that allow for the elimination of invading pathogens, while limiting immunopathological damage to the host. In the present study, we found that conditional deletion of the cell surface receptor Toso on B cells unexpectedly resulted in impaired proinflammatory T cell responses, which led to impaired immune protection in an acute viral infection model and was associated with reduced immunopathological tissue damage in a chronic inflammatory context. Toso exhibited its B cell-inherent immunoregulatory function by negatively controlling the pool of IL-10-competent B1 and B2 B cells, which were characterized by a high degree of self-reactivity and were shown to mediate immunosuppressive activity on inflammatory T cell responses in vivo. Our results indicate that Toso is involved in the differentiation/maintenance of regulatory B cells by fine-tuning B cell receptor activation thresholds. Furthermore, we showed that during influenza A-induced pulmonary inflammation, the application of Toso-specific antibodies selectively induced IL-10-competent B cells at the site of inflammation and resulted in decreased proinflammatory cytokine production by lung T cells. These findings suggest that Toso may serve as a novel therapeutic target to dampen pathogenic T cell responses via the modulation of IL-10-competent regulatory B cells.

  15. The impact of inflammation and immune activation on B cell differentiation during HIV-1 infection

    Directory of Open Access Journals (Sweden)

    Nicolas eRuffin

    2012-01-01

    Full Text Available HIV-1 infection is characterized by continuous antigenic stimulation, chronic immune activation and impaired survival of T and B cells. A decline of resting memory B cells has previously been reported to occur in both children and adults infected with HIV-1; these cells are responsible for mounting and maintaining an adequate serological response to antigens previously encountered in life through natural infection or vaccination. Further understanding of the mechanisms leading to impaired B cell differentiation and germinal center reaction might be essential to design new HIV vaccines and therapies that could improve humoral immune responses in HIV-1 infected individuals. In the present article we summarize the literature and present our view on critical mechanisms of B cell development which are impaired during HIV-1 infection. We also discuss the impact of microbial translocation, a driving force for persistent inflammation during HIV-1 infection, on survival of terminally differentiated B cells and how the altered expression of cytokines/chemokines pivotal for communication between T and B cells in lymphoid tissues may impair formation of memory B cells.

  16. PU.1 cooperates with IRF4 and IRF8 to suppress pre-B cell leukemia

    Science.gov (United States)

    Pang, Swee Heng Milon; Minnich, Martina; Gangatirkar, Pradnya; Zheng, Zhiqiang; Ebert, Anja; Song, Guangchun; Dickins, Ross A; Corcoran, Lynn M; Mullighan, Charles G.; Busslinger, Meinrad; Huntington, Nicholas D; Nutt, Stephen L; Carotta, Sebastian

    2016-01-01

    The Ets family transcription factor PU.1 and the interferon regulatory factor (IRF)4 and IRF8 regulate gene expression by binding to composite DNA sequences known as Ets/interferon consensus elements (EICE). Although all three factors are expressed from the onset of B cell development, single deficiency of these factors in B cell progenitors only mildly impacts on bone marrow B-lymphopoiesis. Here we tested whether PU.1 cooperates with IRF factors in regulating early B cell development. Lack of PU.1 and IRF4 resulted in a partial block in development the pre-B cell stage. The combined deletion of PU.1 and IRF8 reduced recirculating B cell numbers. Strikingly, all PU.1/IRF4 and approximately 50% of PU.1/IRF8 double deficient mice developed pre-B cell acute lymphoblastic leukemia (B-ALL) associated with reduced expression of the established B-lineage tumor suppressor genes, Ikaros and Spi-B. These genes are directly regulated by PU.1/IRF4/IRF8, and restoration of Ikaros or Spi-B expression inhibited leukemic cell growth. In summary, we demonstrate that PU.1, IRF4 and IRF8 cooperate to regulate early B cell development and to prevent pre-B-ALL formation. PMID:26932576

  17. Modeling malware propagation using a carrier compartment

    Science.gov (United States)

    Hernández Guillén, J. D.; Martín del Rey, A.

    2018-03-01

    The great majority of mathematical models proposed to simulate malware spreading are based on systems of ordinary differential equations. These are compartmental models where the devices are classified according to some types: susceptible, exposed, infectious, recovered, etc. As far as we know, there is not any model considering the special class of carrier devices. This type is constituted by the devices whose operative systems is not targeted by the malware (for example, iOS devices for Android malware). In this work a novel mathematical model considering this new compartment is considered. Its qualitative study is presented and a detailed analysis of the efficient control measures is shown by studying the basic reproductive number.

  18. The upper hand on compartment syndrome.

    LENUS (Irish Health Repository)

    Dolan, Roisin T

    2012-11-01

    Metacarpal fractures are common injuries, accounting for approximately 30% to 40% of all hand fractures and with a lifetime incidence of 2.5%. Traditionally regarded as an innocuous injury, metacarpal fractures tend to be associated with successful outcomes after closed reduction and immobilization. Hand compartment syndrome (HCS) is a rare clinical entity with potential devastating consequences in terms of loss of function and quality-of-life outcomes. We discuss the case of a 44-year-old woman presenting with multiple closed metacarpal fractures as a result of low-energy trauma, complicated by acute HCS. We review the presentation, clinical assessment, and optimal surgical management of acute HCS with reference to international literature.

  19. Upregulation of CD19⁺CD24(hi)CD38(hi) regulatory B cells is associated with a reduced risk of acute lung injury in elderly pneumonia patients.

    Science.gov (United States)

    Song, Haihan; Xi, Jianjun; Li, Guang-Gang; Xu, Shumin; Wang, Chunmei; Cheng, Tingting; Li, Hongqiang; Zhang, Ying; Liu, Xiandong; Bai, Jianwen

    2016-04-01

    Acute lung injury (ALI) is a common complication in elderly pneumonia patients who have a rapid progression, and is accompanied by a high mortality rate. Because the treatment options of ALI are limited to supportive care, identifying pneumonia patients who are at higher risk of ALI development is the emphasis of many studies. Here, we approach this problem from an immunological perspective by examining CD19(+)CD24(hi)CD38(hi) B cells, an important participant in acute and chronic inflammation. We find that elderly pneumonia patients have elevated CD19(+)CD24(hi)CD38(hi) B cell frequency compared to healthy individuals. This B cell population may express a higher level of IL-10, which has been was shown to suppress CD4(+) T cell-mediated proinflammatory cytokine interferon gamma (IFNg) and tumor necrosis factor alpha (TNFa) production, through an IL-10-dependent mechanism. We also observe that the frequency of CD19(+)CD24(hi)CD38(hi) B cell is positively correlated with the frequency of CD4(+)CD25(+)Foxp3(+)Tregs in peripheral blood. Moreover, consistent with CD19(+)CD24(hi)CD38(hi) B cell's anti-inflammatory role, we find that pneumonia patients who later developed ALI have reduced level of CD19(+)CD24(hi)CD38(hi) B cells. Together, our results demonstrated that CD19(+)CD24(hi)CD38(hi) B cells in pneumonia patients possess regulatory function in vivo, and are associated with a reduced ALI risk.

  20. Rgs13 constrains early B cell responses and limits germinal center sizes.

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    Il-Young Hwang

    Full Text Available Germinal centers (GCs are microanatomic structures that develop in secondary lymphoid organs in response to antigenic stimulation. Within GCs B cells clonally expand and their immunoglobulin genes undergo class switch recombination and somatic hypermutation. Transcriptional profiling has identified a number of genes that are prominently expressed in GC B cells. Among them is Rgs13, which encodes an RGS protein with a dual function. Its canonical function is to accelerate the intrinsic GTPase activity of heterotrimeric G-protein α subunits at the plasma membrane, thereby limiting heterotrimeric G-protein signaling. A unique, non-canonical function of RGS13 occurs following translocation to the nucleus, where it represses CREB transcriptional activity. The functional role of RGS13 in GC B cells is unknown. To create a surrogate marker for Rgs13 expression and a loss of function mutation, we inserted a GFP coding region into the Rgs13 genomic locus. Following immunization GFP expression rapidly increased in activated B cells, persisted in GC B cells, but declined in newly generated memory B and plasma cells. Intravital microscopy of the inguinal lymph node (LN of immunized mice revealed the rapid appearance of GFP(+ cells at LN interfollicular regions and along the T/B cell bor