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Sample records for ebv-associated post-transplantation b-cell

  1. EBV-associated post-transplantation B-cell lymphoproliferative disorder following allogenic stem cell transplantation for acute lymphoblastic leukaemia: tumor regression after reduction of immunosuppression - a case report

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    Niedobitek Gerald

    2010-03-01

    Full Text Available Abstract Epstein-Barr virus (EBV-associated B-cell post-transplantation lymphoproliferative disorder (PTLD is a severe complication following stem cell transplantation. This is believed to occur as a result of iatrogenic immunosuppression leading to a relaxation of T-cell control of EBV infection and thus allowing viral reactivation and proliferation of EBV-infected B-lymphocytes. In support of this notion, reduction of immunosuppressive therapy may lead to regression of PTLD. We present a case of an 18-year-old male developing a monomorphic B-cell PTLD 2 months after receiving an allogenic stem cell transplant for acute lymphoblastic leukemia. Reduction of immunosuppressive therapy led to regression of lymphadenopathy. Nevertheless, the patient died 3 months afterwards due to extensive graft-vs.-host-disease and sepsis. As a diagnostic lymph node biopsy was performed only after reduction of immunosuppressive therapy, we are able to study the histopathological changes characterizing PTLD regression. We observed extensive apoptosis of blast cells, accompanied by an abundant infiltrate comprising predominantly CD8-positive, Granzyme B-positive T-cells. This observation supports the idea that regression of PTLD is mediated by cytotoxic T-cells and is in keeping with the observation that T-cell depletion, represents a major risk factor for the development of PTLD.

  2. Epigenetic Impact on EBV Associated B-Cell Lymphomagenesis

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    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.

  3. EBV-associated post-transplant lymphoproliferative disorder after umbilical cord blood transplantation in adults with hematological diseases.

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    Sanz, J; Arango, M; Senent, L; Jarque, I; Montesinos, P; Sempere, A; Lorenzo, I; Martín, G; Moscardó, F; Mayordomo, E; Salavert, M; Cañigral, C; Boluda, B; Salazar, C; López-Hontangas, J L; Sanz, M A; Sanz, G F

    2014-03-01

    We analyzed the incidence, clinicopathological features, risk factors and prognosis of patients with EBV-associated post-transplant lymphoproliferative disorder (EBV-PTLD) in 288 adults undergoing umbilical cord blood transplantation (UCBT) at a single institution. Twelve patients developed proven EBV-PTLD at a median time of 73 days (range, 36-812). Three-year cumulative incidence (CI) of EBV-PTLD was 4.3% (95% CI: 1.9-6.7). All patients presented with extranodal involvement. Most frequently affected sites were the liver, spleen, central nervous system (CNS), Waldeyer's ring and BM in 7, 6, 4, 3 and 3 patients, respectively. One patient had polymorphic and 11 had monomorphic EBV-PTLD (7 diffuse large B-cell lymphomas not otherwise specified, 4 plasmablastic lymphomas). We confirmed donor origin and EBV infection in all histological samples. EBV-PTLD was the cause of death in 11 patients at a median time of 23 days (range, 1-84). The 3-year CI of EBV-PTLD was 12.9% (95% CI: 3.2-22.5) and 2.6% (95% CI: 0.5-4.7) for patients receiving reduced-intensity conditioning (RIC) and myeloablative conditioning, respectively (P<0.0001). In conclusion, adults with EBV-PTLD after UCBT showed frequent visceral and CNS involvement. The prognosis was poor despite routine viral monitoring and early intervention. An increased risk of EBV-PTLD was noted among recipients of RIC regimens.

  4. Virus and autoantigen-specific CD4+ T cells are key effectors in a SCID mouse model of EBV-associated post-transplant lymphoproliferative disorders.

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    Linnerbauer, Stefanie; Behrends, Uta; Adhikary, Dinesh; Witter, Klaus; Bornkamm, Georg W; Mautner, Josef

    2014-05-01

    Polyclonal Epstein-Barr virus (EBV)-infected B cell line (lymphoblastoid cell lines; LCL)-stimulated T-cell preparations have been successfully used to treat EBV-positive post-transplant lymphoproliferative disorders (PTLD) in transplant recipients, but function and specificity of the CD4+ component are still poorly defined. Here, we assessed the tumor-protective potential of different CD4+ T-cell specificities in a PTLD-SCID mouse model. Injection of different virus-specific CD4+ T-cell clones showed that single specificities were capable of prolonging mouse survival and that the degree of tumor protection directly correlated with recognition of target cells in vitro. Surprisingly, some CD4+ T-cell clones promoted tumor development, suggesting that besides antigen recognition, still elusive functional differences exist among virus-specific T cells. Of several EBV-specific CD4+ T-cell clones tested, those directed against virion antigens proved most tumor-protective. However, enriching these specificities in LCL-stimulated preparations conferred no additional survival benefit. Instead, CD4+ T cells specific for unknown, probably self-antigens were identified as principal antitumoral effectors in LCL-stimulated T-cell lines. These results indicate that virion and still unidentified cellular antigens are crucial targets of the CD4+ T-cell response in this preclinical PTLD-model and that enriching the corresponding T-cell specificities in therapeutic preparations may enhance their clinical efficacy. Moreover, the expression in several EBV-negative B-cell lymphoma cell lines implies that these putative autoantigen(s) might also qualify as targets for T-cell-based immunotherapy of virus-negative B cell malignancies.

  5. Down-regulation of BLIMP1α by the EBV oncogene, LMP-1, disrupts the plasma cell differentiation program and prevents viral replication in B cells: implications for the pathogenesis of EBV-associated B-cell lymphomas.

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    Vrzalikova, Katerina; Vockerodt, Martina; Leonard, Sarah; Bell, Andrew; Wei, Wenbin; Schrader, Alexandra; Wright, Kenneth L; Kube, Dieter; Rowe, Martin; Woodman, Ciaran B; Murray, Paul G

    2011-06-02

    An important pathogenic event in Epstein-Barr virus (EBV)-associated lymphomas is the suppression of virus replication, which would otherwise lead to cell death. Because virus replication in B cells is intimately linked to their differentiation toward plasma cells, we asked whether the physiologic signals that drive normal B-cell differentiation are absent in EBV-transformed cells. We focused on BLIMP1α, a transcription factor that is required for plasma cell differentiation and that is inactivated in diffuse large B-cell lymphomas. We show that BLIMP1α expression is down-regulated after EBV infection of primary germinal center B cells and that the EBV oncogene, latent membrane protein-1 (LMP-1), is alone capable of inducing this down-regulation in these cells. Furthermore, the down-regulation of BLIMP1α by LMP-1 was accompanied by a partial disruption of the BLIMP1α transcriptional program, including the aberrant induction of MYC, the repression of which is required for terminal differentiation. Finally, we show that the ectopic expression of BLIMP1α in EBV-transformed cells can induce the viral lytic cycle. Our results suggest that LMP-1 expression in progenitor germinal center B cells could contribute to the pathogenesis of EBV-associated lymphomas by down-regulating BLIMP1α, in turn preventing plasma cell differentiation and induction of the viral lytic cycle.

  6. EBV-negative monomorphic B-cell post-transplant lymphoproliferative disorders are pathologically distinct from EBV-positive cases and frequently contain TP53 mutations.

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    Courville, Elizabeth L; Yohe, Sophia; Chou, David; Nardi, Valentina; Lazaryan, Aleksandr; Thakral, Beenu; Nelson, Andrew C; Ferry, Judith A; Sohani, Aliyah R

    2016-10-01

    Monomorphic post-transplant lymphoproliferative disorder commonly resembles diffuse large B-cell lymphoma or Burkitt lymphoma, and most are Epstein-Barr virus (EBV) positive. We retrospectively identified 32 cases of monomorphic post-transplant lymphoproliferative disorder from two institutions and evaluated EBV in situ hybridization; TP53 mutation status; p53, CD30, myc, and BCL2 expression by immunohistochemistry; proliferation index by Ki67; and germinal center vs non-germinal center immunophenotype by Hans criteria. Post-transplant lymphoproliferative disorder arose after hematopoietic stem cell transplant in five and solid organ transplant in 27 patients, a median of 4 and 96 months after transplant, respectively (overall median latency 71 months, range 2-295). The most common morphology was diffuse large B-cell lymphoma (28 cases), with three cases of Burkitt lymphoma, and one case of plasmablastic lymphoma. Ten cases (31%) were EBV negative. Of those with the morphology of diffuse large B-cell lymphoma, the EBV-negative cases were more frequently TP53-mutated (Pnegative (Ppost-transplant lymphoproliferative disorder were older with a longer latency from time of transplant to diagnosis (Ppost-transplant setting and underscores differences between EBV-positive and EBV-negative post-transplant lymphoproliferative disorder in terms of immunophenotype and TP53 mutation frequency, supporting an alternative pathogenesis for EBV-negative post-transplant lymphoproliferative disorder.

  7. Coexistence of age-related EBV-associated follicular hyperplasia and large B-cell EBV+ lymphoma of the elderly. Two distinct features of the same T-cell dysfunction related to senescence?

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    Gibier, Jean-Baptiste; Bouchindhomme, Brigitte; Dubois, Romain; Hivert, Benedicte; Grardel, Nathalie; Copin, Marie-Christine

    2017-03-01

    Age-related EBV-associated lymphoproliferative disorders form a new clinicopathological group. Until recently, this group was associated with diffuse large B-cell lymphoma (DLBCL), characterised by an aggressive clinical presentation and a poor prognosis. Recent findings in Western Caucasian patients, however, suggest that this entity covers a wide spectrum of diseases, ranging from reactive follicular hyperplasia (HR) to DLBCL. We report the case of an 85-year-old Caucasian man showing lymphadenopathy and numerous hypodense lesions of the liver. Examination of a lymph node revealed follicular hyperplasia with EBV expression confined to germinal centres. The patient was treated with Rituximab and subsequently, the lesions of the liver were explored. They showed extensive necrosis and a polymorphic large B-cell population with strong EBV expression. This is the first report to describe age-related EBV-associated follicular hyperplasia at one site coexisting with DLBCL at another. This case warrants undertaking further investigations each time a diagnosis of age-related EBV-HR is associated with extranodal lesions. Copyright © 2016 Elsevier GmbH. All rights reserved.

  8. A case of age-related Epstein-Barr virus (EBV)-associated B cell lymphoproliferative disorder, so-called polymorphous subtype, of the mandible, with a review of the literature.

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    Kikuchi, Kentaro; Fukunaga, Shuichi; Inoue, Harumi; Miyazaki, Yuji; Kojima, Masaru; Ide, Fumio; Kusama, Kaoru

    2013-06-01

    Epstein-Barr virus (EBV) is known to be associated with the development of lymphomas in immunocompromised patients. Recently, age-related immune impairment has been recognized as a predisposing factor in the development of EBV-driven lymphoproliferative disorders (LPDs) in elderly patients without any known immunodeficiency or prior lymphoma. In approximately 70% of reported cases, the affected sites have been extranodal, such as the skin, lung, tonsil and stomach. However, age-related EBV-associated B cell (EBV + B cell) LPD is extremely rare in the oral cavity. Here we report a 71-year-old Japanese man who developed an EBV + B cell LPD resembling classical Hodgkin lymphoma (CHL)--so-called polymorphous subtype-of the mandible. Histopathologically, infiltration of large atypical lymphoid cells including Hodgkin or Reed-Sternberg-like cells into granulation tissue with marked necrosis was found in the mandibular bone. Immunohistochemical analysis revealed that the large atypical Hodgkin or Reed-Sternberg-like cells were CD3-, CD15-, CD20+, CD30+ and Epstein-Barr virus (EBV)-latent infection membrane protein-1 (LMP-1)+. In situ hybridization (ISH) demonstrated EBV-encoded small RNA (EBER) + in numerous Hodgkin or Reed-Sternberg-like cells. EBNA-2 was detected by polymerase chain reaction (PCR) using an extract from the formalin-fixed, paraffin-embedded specimen. To our knowledge, this is the first reported case of the polymorphous subtype of age-related EBV + B cell LPD affecting the mandible.

  9. Deconvoluting post-transplant immunity: cell subset-specific mapping reveals pathways for activation and expansion of memory T, monocytes and B cells.

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    Yevgeniy A Grigoryev

    Full Text Available A major challenge for the field of transplantation is the lack of understanding of genomic and molecular drivers of early post-transplant immunity. The early immune response creates a complex milieu that determines the course of ensuing immune events and the ultimate outcome of the transplant. The objective of the current study was to mechanistically deconvolute the early immune response by purifying and profiling the constituent cell subsets of the peripheral blood. We employed genome-wide profiling of whole blood and purified CD4, CD8, B cells and monocytes in tandem with high-throughput laser-scanning cytometry in 10 kidney transplants sampled serially pre-transplant, 1, 2, 4, 8 and 12 weeks. Cytometry confirmed early cell subset depletion by antibody induction and immunosuppression. Multiple markers revealed the activation and proliferative expansion of CD45RO(+CD62L(- effector memory CD4/CD8 T cells as well as progressive activation of monocytes and B cells. Next, we mechanistically deconvoluted early post-transplant immunity by serial monitoring of whole blood using DNA microarrays. Parallel analysis of cell subset-specific gene expression revealed a unique spectrum of time-dependent changes and functional pathways. Gene expression profiling results were validated with 157 different probesets matching all 65 antigens detected by cytometry. Thus, serial blood cell monitoring reflects the profound changes in blood cell composition and immune activation early post-transplant. Each cell subset reveals distinct pathways and functional programs. These changes illuminate a complex, early phase of immunity and inflammation that includes activation and proliferative expansion of the memory effector and regulatory cells that may determine the phenotype and outcome of the kidney transplant.

  10. Epstein-Barr Virus (EBV)-associated gastric carcinoma.

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    Iizasa, Hisashi; Nanbo, Asuka; Nishikawa, Jun; Jinushi, Masahisa; Yoshiyama, Hironori

    2012-12-01

    The ubiquitous Epstein-Barr virus (EBV) is associated with several human tumors, which include lymphoid and epithelial malignancies. It is known that EBV persistently infects the memory B cell pool of healthy individuals by activating growth and survival signaling pathways that can contribute to B cell lymphomagenesis. Although the monoclonal proliferation of EBV-infected cells can be observed in epithelial tumors, such as nasopharyngeal carcinoma and EBV-associated gastric carcinoma, the precise role of EBV in the carcinogenic progress is not fully understood. This review features characteristics and current understanding of EBV-associated gastric carcinoma. EBV-associated gastric carcinoma comprises almost 10% of all gastric carcinoma cases and expresses restricted EBV latent genes (Latency I). Firstly, definition, epidemiology, and clinical features are discussed. Then, the route of infection and carcinogenic role of viral genes are presented. Of particular interest, the association with frequent genomic CpG methylation and role of miRNA for carcinogenesis are topically discussed. Finally, the possibility of therapies targeting EBV-associated gastric carcinoma is proposed.

  11. Susceptibility-weighted imaging and diffusion-weighted imaging findings in central nervous system monomorphic B cell post-transplant lymphoproliferative disorder before and after treatment and comparison with primary B cell central nervous system lymphoma.

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    Ginat, Daniel Thomas; Purakal, Alixandra; Pytel, Peter

    2015-11-01

    The purpose of this article is to review the MRI features of monomorphic central nervous system post-transplant lymphoproliferative disorder (CNS PTLD), including diffusion-weighted and susceptibility-weighted sequences before and after treatment and to compare the imaging findings with those of primary central nervous system B cell lymphoma (PCNS BCL). Retrospective review of the brain MRI characteristics in patients with pathology proven monomorphic CNS PTLD and PCNS BCL was performed. In particular, the enhancement, diffusion-weighted, susceptibility-weighted MRI characteristics of the lesions were evaluated. In addition, the diffusion-weighted, susceptibility-weighted MRI features after treatment for CNS PTLD were evaluated. A total of 12 lesions in six patients with CNS PTLD and 12 lesions in nine patients with PCNS BCL were identified on MRI. Among the CNS PTLD lesions with post-contrast images, 80 % demonstrated peripheral enhancement. All of the CNS PTLD lesions contained foci of intratumoral susceptibility signal (ITSS) and the average mean ADC values and ratios were 0.892 × 10(-3) mm(2)/s (standard deviation: 0.082 × 10(-3) mm(2)/s) and 1.19 (standard deviation: 0.15), respectively. On the other hand, 75 % of the PCNS BCL displayed diffuse enhancement, two cases (16.7 %) contained ITSS, and the mean ADC values and ratios were 0.721 × 10(-3) mm(2)/s (standard deviation: 0.093 × 10(-3) mm(2)/s), and 0.99 (standard deviation: 0.17), respectively. Thus, the presence of heterogeneous lesions with ITSS that do not necessarily have as extensive restricted diffusion as PCNS BCL is suggestive of CNS PTLD in the appropriate clinical setting. The preliminary data in this series suggests that diffusion-weighted imaging may serve as a useful biomarker for monitoring treatment response, in which successful treatment of CNS PTLD may result in increased ADC values. In addition, foci of susceptibility effect in CNS PTLD tend to persist or increase over the course of

  12. EBV-positive B cell cerebral lymphoma 12 years after sex-mismatched kidney transplantation: post-transplant lymphoproliferative disorder or donor-derived lymphoma?

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    Phelan, Paul J

    2010-06-01

    We present a follow-up case report of possible transmission of lymphoma 12 years after deceased-donor renal transplantation from a male donor who was found at autopsy to have had an occult lymphoma. The female recipient underwent prompt transplant nephrectomy. However, 12 years later, she presented with cerebral B cell lymphoma. A donor origin for the cerebral lymphoma was supported by in situ hybridization demonstration of a Y chromosome in the lymphoma. There was a dramatic resolution of the cerebral lesions with tapering of immunosuppression and introduction of rituximab treatment. The finding of a Y chromosome in the cerebral lymphoma does not exclude a host contribution to lymphoma development.

  13. Expression of HSV-1 receptors in EBV-associated lymphoproliferative disease determines susceptibility to oncolytic HSV

    NARCIS (Netherlands)

    Wang, P.Y.; Currier, M.A.; Hansford, L.; Kaplan, D.; Chiocca, E.A.; Uchida, H.; Goins, W.F.; Cohen, J.B.; Glorioso, J.C.; Kuppevelt, T.H. van; Mo, X.; Cripe, T.P.

    2013-01-01

    Epstein-Barr virus (EBV)-associated B-cell lymphoproliferative disease (LPD) after hematopoietic stem cell or solid organ transplantation remains a life-threatening complication. Expression of the virus-encoded gene product, EBER, has been shown to prevent apoptosis via blockade of PKR activation. A

  14. Prevention of EBV lymphoma development by oncolytic myxoma virus in a murine xenograft model of post-transplant lymphoproliferative disease

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    Kim, Manbok, E-mail: manbok66@dankook.ac.kr [Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610 (United States); Rahman, Masmudur M. [Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610 (United States); Cogle, Christopher R. [Department of Hematology/Oncology, University of Florida, Gainesville, FL 32610 (United States); McFadden, Grant [Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610 (United States)

    2015-07-10

    Epstein–Barr virus (EBV) has been associated with a variety of epithelial and hematologic malignancies, including B-, T- and NK cell-lymphomas, Hodgkin's disease (HD), post-transplant lymphoproliferative diseases (LPDs), nasopharyngeal and gastric carcinomas, smooth muscle tumors, and HIV-associated lymphomas. Currently, treatment options for EBV-associated malignancies are limited. We have previously shown that myxoma virus specifically targets various human solid tumors and leukemia cells in a variety of animal models, while sparing normal human or murine tissues. Since transplant recipients of bone marrow or solid organs often develop EBV-associated post-transplant LPDs and lymphoma, myxoma virus may be of utility to prevent EBV-associated malignancies in immunocompromised transplant patients where treatment options are frequently limited. In this report, we demonstrate the safety and efficacy of myxoma virus purging as a prophylactic strategy for preventing post-transplant EBV-transformed human lymphomas, using a highly immunosuppressed mouse xenotransplantation model. This provides support for developing myxoma virus as a potential oncolytic therapy for preventing EBV-associated LPDs following transplantation of bone marrow or solid organ allografts. - Highlights: • Myxoma virus effectively infects and purges EBV lymphoma cells in vivo. • Oncolytic myxoma virus effectively eradicates oncogenic EBV tumorigenesis. • Ex vivo pre-treatment of myxoma virus can be effective as a preventive treatment modality for post-transplant lymphoproliferative diseases.

  15. Prevention of EBV lymphoma development by oncolytic myxoma virus in a murine xenograft model of post-transplant lymphoproliferative disease.

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    Kim, Manbok; Rahman, Masmudur M; Cogle, Christopher R; McFadden, Grant

    2015-07-10

    Epstein-Barr virus (EBV) has been associated with a variety of epithelial and hematologic malignancies, including B-, T- and NK cell-lymphomas, Hodgkin's disease (HD), post-transplant lymphoproliferative diseases (LPDs), nasopharyngeal and gastric carcinomas, smooth muscle tumors, and HIV-associated lymphomas. Currently, treatment options for EBV-associated malignancies are limited. We have previously shown that myxoma virus specifically targets various human solid tumors and leukemia cells in a variety of animal models, while sparing normal human or murine tissues. Since transplant recipients of bone marrow or solid organs often develop EBV-associated post-transplant LPDs and lymphoma, myxoma virus may be of utility to prevent EBV-associated malignancies in immunocompromised transplant patients where treatment options are frequently limited. In this report, we demonstrate the safety and efficacy of myxoma virus purging as a prophylactic strategy for preventing post-transplant EBV-transformed human lymphomas, using a highly immunosuppressed mouse xenotransplantation model. This provides support for developing myxoma virus as a potential oncolytic therapy for preventing EBV-associated LPDs following transplantation of bone marrow or solid organ allografts.

  16. EBV-associated gastric carcinoma in high- and low-incidence areas for nasopharyngeal carcinoma

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    Boysen, T.; Mohammadi, M.; Melbye, M.;

    2009-01-01

    BACKGROUND: Approximately 10% of gastric carcinomas are associated with Epstein-Barr virus (EBV). The Inuit in Greenland have a high incidence of EBV-associated nasopharyngeal carcinoma. METHODS: We conducted a population-based case-control study comparing gastric carcinomas in Greenland...... and in Denmark. RESULTS: The prevalence rate of EBV-associated gastric carcinomas was 8.5% in both populations. CONCLUSION: The findings of this study argue against a general susceptibility to EBV-associated carcinomas among the Inuit....

  17. Emerging therapeutic strategies for Epstein-Barr virus+ post-transplant lymphoproliferative disorder.

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    Hatton, Olivia; Martinez, Olivia M; Esquivel, Carlos O

    2012-05-01

    De novo malignancies represent an increasing concern in the transplant population, particularly as long-term graft and patient survival improves. EBV-associated B-cell lymphoma in the setting of PTLD is the leading malignancy in children following solid organ transplantation. Therapeutic strategies can be categorized as pharmacologic, biologic, and cell-based but the variable efficacy of these approaches and the complexity of PTLD suggest that new treatment options are warranted. Here, we review current therapeutic strategies for treatment of PTLD. We also describe the life cycle of EBV, addressing the viral mechanisms that contribute to the genesis and persistence of EBV+ B-cell lymphomas. Specifically, we focus on the oncogenic signaling pathways activated by the EBV LMP1 and LMP2a to understand the underlying mechanisms and mediators of lymphomagenesis with the goal of identifying novel, rational therapeutic targets for the treatment of EBV-associated malignancies.

  18. Rapidly progressive post-transplant lymphoproliferative disease following withdrawal of sirolimus.

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    Mendelson, Marc; Barday, Zunaid; Eastman, Roland; Le Feuvre, David; Candy, Sally; Wu, Hue-Tsi; Swanepoel, Charles

    2012-08-24

    Sirolimus, a potent inhibitor of B- and T-cell activation. is a commonly used immunosuppressant after renal transplantation. Withdrawal of sirolimus from the immunosuppression regimen may reduce B-cell surveillance. We present a case of rapidly progressive central nervous system (CNS) polymorphic Epstein-Barr virus (EBV)-related post-transplant lymphoproliferative disorder following the withdrawal of sirolimus.

  19. Successful Treatment of Posttransplant EBV-Associated Lymphoma and Plasmacytoma Solely Localized to the CNS

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    Per Boye Hansen

    2012-01-01

    Full Text Available Two patients with diabetic nephropathy were diagnosed with primary central nervous system posttransplant Epstein-Barr-virus-associated lymphoproliferative disorder (PTLD 3 years after renal transplantation. The histological diagnoses of the isolated brain tumors were diffuse large B-cell lymphoma and plasmacytoma. Considerable co-morbidity precluded intensive chemotherapy. The first patient with lymphoid CD20+ PTLD had a partial resection of her tumor performed. She was treated with 4 weekly doses of rituximab, ganciclovir and prednisolone; the posttransplant immune suppression (tacrolimus was reduced. After 4 weeks of treatment a magnetic resonance imaging (MRI demonstrated complete regression of the CNS lesion. The patient continues to receive rituximab (every second month, valgangciclovir and low-dose prednisolone. Twenty-two months after initiation of therapy, she is still in complete remission. The second patient was only treated with craniospinal irradiation involving the medulla to the second cervical vertebra and valgangciclovir. Moreover, the posttransplant immune suppression was reduced. A new MRI two months after initiation of therapy showed a complete regression of the lesions in the CNS; this was again demonstrated by a MRI after 19 months. These 2 cases illustrate interesting alternative treatments of PTLD. To our knowledge, an EBV-associated PTLD of plasmacytic origin isolated to the CNS has never been described before.

  20. High-Dose Y-90-Ibritumomab Tiuxetan Added to Reduced-Intensity Allogeneic Stem Cell Transplant Regimen for Relapsed or Refractory Aggressive B-Cell Lymphoma

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    2016-07-08

    Post-Transplant Lymphoproliferative Disorder; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent B-Cell Non-Hodgkin Lymphoma; Recurrent Burkitt Lymphoma; Refractory B-Cell Non-Hodgkin Lymphoma; Refractory Burkitt Lymphoma; Refractory Diffuse Large B-Cell Lymphoma

  1. Occurrence and prognostic relevance of CD30 expression in post-transplant lymphoproliferative disorders

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    Vase, Maja Ølholm; Maksten, Eva Futtrup; Bendix, Knud;

    2015-01-01

    Post-transplant lymphoproliferative disorders (PTLDs) are potentiallyfatal, often Epstein-Barr virus (EBV)-driven neoplasias developing in immunocompromised hosts. Initial treatment usually consists of a reduction in immunosuppressive therapy and/or rituximab with or without chemotherapy. However...... favorable outcome. For diffuse large B-cell lymphoma (DLBCL)-type PTLD this was regardless of EBV status, and remained significant in multivariate analysis. Cell-of-origin had no independent prognostic value in our series of DLBCL PTLD....

  2. Characterization of post transplantation lymphoma in feline renal transplant recipients.

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    Durham, A C; Mariano, A D; Holmes, E S; Aronson, L

    2014-01-01

    The development of malignant neoplasia following solid organ transplantation and immunosuppression is well recognized in man. Post-transplantation malignant tumours include non-melanoma skin cancers, non-Hodgkin's lymphoma and Kaposi's sarcoma and many of these cancers have a known or suspected viral cause. A similar increased incidence of cancer is seen in cats that have received a renal transplant and lymphoma is the predominant neoplasm in this population. This study examines a population of cats that received renal transplants at the University of Pennsylvania School of Veterinary Medicine and subsequently developed neoplasia. From 1998 to 2010, 111 cats were transplanted and 25 cats developed cancer (22.5%). Fourteen of the 25 cats were diagnosed with lymphoma (56%), making it the most common tumour in this patient population. The median interval between transplantation and diagnosis of lymphoma was 617 days and the median survival time (MST) following the diagnosis of lymphoma was 2 days. Tissues from seven of these cats were available for histopathological review as either samples collected at necropsy examination (n = 5) or biopsy submissions (n = 2). Five of these cats had multiorgan involvement with sites including the liver, spleen, peripheral and mesenteric lymph nodes, small intestine, urinary bladder, heart, mesenteric fat and body wall. Four of the cats with multiorgan disease had involvement of the renal allograft two of which also had lymphoma of the native kidney. All lymphomas were classified as mid to high grade, diffuse large B-cell lymphoma, which is also the most common lymphoma subtype in human cases of post-transplantation lymphoproliferative disorders.

  3. Post-transplantation diabetes mellitus: an overview

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    Igor Aleksandrovich Sklyanik

    2015-04-01

    Full Text Available This review presents an analysis of clinical and experimental studies related to post-transplantation diabetes mellitus (PTDM – a specific complication after solid organ transplantation.A search of the databases eLibrary, PubMed and Scopus using the keywords «posttransplantation diabetes mellitus», «new onset diabetes after transplantation», «transplantation» and «immunosuppression» yielded in 523 results, including four from Russian literature (one original research manuscript. The analysis included original research, reviews, meta-analyses and monographs published not before 2005 in Russian and English. A total of 60 relevant original researches and reviews were included in this review.Diagnostic criteria, disease risk factors and potential pathogenic mechanisms were all considered. The mechanisms of the diabetogenic effect of modern immunosuppressive drugs were analysed. The principles of pre- and post-transplantation screening for PTDM and optimal management strategies for patients with PTDM are presented. The current controversial issues concerning the various aspects of PTDM are discussed.

  4. Human-derived IgG level as an indicator for EBV-associated lymphoma model in Hu-PBL/SCID chimeras.

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    Tang, Yunlian; He, Rongfang; Zhang, Yang; Liu, Fang; Cheng, Ailan; Wu, Yimou; Gan, Runliang

    2011-05-09

    Epstein-Barr virus (EBV) has a close association with various types of human lymphomas. Animal models are essential to elucidate the pathogenesis of human EBV-associated lymphomas. The aim of the present study is to evaluate the association between human IgG concentration and EBV-associated lymphoma development in huPBL/SCID mice. Human peripheral blood lymphocytes (hu-PBL) from EBV-seropositive donors were inoculated intraperitoneally into SCID mouse. Immunohistochemical staining was used to examine differentiated antigens of tumor cells. EBV infection of the induced tumors was detected by in situ hybridization. IgG concentrations in the serums of 12 SCID mice were measured by unidirectional immunodiffusion assay. 21 out of 29 mice developed tumors in their body. Immunohistochemical staining showed that all induced tumors were LCA (leukocyte common antigen) positive, B-cell markers (CD20, CD79a) positive, and T-cell markers (both CD3 and CD45RO) negative. The tumors can be diagnosed as human B-cell lymphomas by these morphological and immunohistochemical features. In situ hybridization exhibited resultant tumor cells had EBV encoded small RNA-1 (EBER-1). Human-derived IgG could be found in the serum from SCID mice on the 15th day following hu-PBL transplantation, and IgG levels increased with the tumor development in 6 hu-PBL/SCID chimeras. Intraperitoneal transfer of hu-PBLs from EBV+ donors to SCID mice leads to high human IgG levels in mouse serum and B cell lymphomas. Our findings suggest that increasing levels of human-derived IgG in peripheral blood from hu-PBL/SCID mice could be used to monitor EBV-related human B-cell lymphoma development in experimental animals.

  5. Post-transplantation primary central nervous system lymphoma in a patient with systemic lupus erythematosus and prolonged use of immunosuppressant.

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    Tse, Teresa P K; Chan, Allan N L; Chan, Tony K T; Po, Y C

    2014-12-01

    Post-transplantation primary central nervous system lymphoma is an uncommon and fatal post-transplant lymphoproliferative disorder. Such lymphomas have been described in only a few case series in the literature. The incidence of this condition is rising with improved survival after organ transplantation. A case of post-transplantation primary central nervous system lymphoma in a young Chinese woman with systemic lupus erythematosus is described here. She presented with right-sided weakness and memory loss after tooth extraction 2 weeks before admission. Contrast computed tomography of the brain demonstrated a contrast rim-enhancing lesion over the left frontal lobe. With a history of recent dental procedure, long-term immunosuppressive therapy and computed tomography findings, cerebral abscess was highly suspected. Emergency operation was performed. Histopathology showed post-transplantation primary central nervous system lymphoma, with cells positive for B-cell marker CD20. Immunosuppressant was stopped and she was treated with radiotherapy and rituximab (anti-CD20 monoclonal antibody). She remained disease-free at 16 months. Post-transplantation primary central nervous system lymphoma is rare with variable presentation and radiological features. We believe rituximab may have a role in the treatment of such lymphomas.

  6. Post-transplant distal limb syndrome

    Directory of Open Access Journals (Sweden)

    María Florencia Borghi Torzillo

    2017-02-01

    Full Text Available The post-transplant distal limb syndrome is a not well known entity, with a prevalence of 5% in patients with renal transplant. Its diagnosis is based on clinical symptoms, bone scintigraphy and MRI, it has a benign course and the patient recovers without sequel. We present the case of a 37-year-old male, with medical history of hypertension, Berger's disease in 1999 that required dialysis three times a week for four years (2009-2013 and renal transplant in 2013. The patient consults on January 2014 referring severe pain in both feet, with sudden onset; he remembers the exact date of the beginning of the pain and denies trauma, pain prevents ambulation. The bone scintigraphy shows pathological uptake in both feet with no difference between the two. Although there is no treatment for this disease, it has a benign course

  7. Post-transplantation Infections in Bolivia.

    Science.gov (United States)

    Arze, S; Arze, L; Abecia, C

    2016-03-01

    Over 26 years, we found 46 infectious episodes in 350 kidney transplant recipients. Fifteen were urinary tract infections, recurrent in 4 patients. There were 8 cytomegalovirus infections, three of them fatal when intravenous (IV) ganciclovir was not available. Seven patients had a reactivation of tuberculosis (TB) in the pleura, cervical spine, lumbar spine, knee, ankle, skin and peritoneum, respectively, and were all resolved satisfactorily with conventional anti-TB therapy. Three patients transplanted before routine prophylaxis with the use of acyclovir developed an extensive herpes zoster infection in the 1st 6 months after transplantation, which was resolved with the use of oral acyclovir, and 1 had a disseminated herpes simplex infection resolved with the use of IV acyclovir. Three patients transplanted before routine prophylaxis with trimethoprim sulfa developed Pneumocystis carinii pneumonia in the 1st 6 months after transplantation, which was fatal in one of them. In 2 patients, we found a Nocardia infection, confined to the lung, which was cured in one of the cases and systemic and fatal in the other. Two patients transplanted before routine prophylaxis with the use of nystatin developed esophageal candidiasis in the 1st 6 months after transplantation. One patient developed infective endocarditis in a stenotic bicuspid aortic valve and died 10 years later after another incident of infective endocarditis at the prosthetic aortic valve. Two patients developed an extensive condyloma at the penis, perianal region, and perineum owing to human papillomavirus, requiring extensive surgical resection and podophyllin applications. Another patient developed fatal post-transplantation lymphoproliferative disease due to Epstein-Barr virus infection 15 years after transplantation. One patient developed a severe and fatal mucocutaneous leishmaniasis with no response to conventional antimonial therapy. It is interesting to note that despite Chagas disease being endemic

  8. A spectrum of basaloid morphology in a subset of EBV-associated "lymphoepithelial carcinomas" of major salivary glands

    DEFF Research Database (Denmark)

    Friborg, Jeppe Tang; Therkildsen, Marianne Hamilton; Homoe, Preben;

    2012-01-01

    salivary gland carcinomas. Amongst primary LEC of major salivary gland, most cases reported in the literature have represented typical nasopharynx-like tumors. Variants of Epstein-Barr Virus (EBV) associated LEC have not been described previously, to the best of our knowledge. In this report, we describe 4...... EBV-associated major salivary gland LECs with prominent basaloid morphology, which represent 22 % of a cohort of 18 salivary LECs from an Inuit population in Greenland. The features described in these cases raise a differential diagnosis of other basaloid tumors, particularly in light of the salivary...

  9. Isolated Post-Transplantation Lymphoproliferative Disease Involving the Breast and Axilla as Peripheral T-cell Lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Ji-Young [Department of Radiology, Kangnam Sacred Heart Hospital, Hallym University College of Medicine, Seoul 150-950 (Korea, Republic of); Cha, Eun Suk; Lee, Jee Eun [Department of Radiology, Ewha Womans University School of Medicine, Seoul 158-710 (Korea, Republic of); Sung, Sun Hee [Department of Pathology, Ewha Womans University School of Medicine, Seoul 158-710 (Korea, Republic of)

    2013-07-01

    Post-transplantation lymphoproliferative disorders (PTLDs) are a heterogeneous group of diseases that represent serious complications following immunosuppressive therapy for solid organ or hematopoietic-cell recipients. In contrast to B-cell PTLD, T-cell PTLD is less frequent and is not usually associated with Epstein Barr Virus infection. Moreover, to our knowledge, isolated T-cell PTLD involving the breast is extremely rare and this condition has never been reported previously in the literature. Herein, we report a rare case of isolated T-cell PTLD of the breast that occurred after a patient had been treated for allogeneic peripheral blood stem cell transplantation due to acute myeloblastic leukemia.

  10. Establishment and operation of a Good Manufacturing Practice-compliant allogeneic Epstein-Barr virus (EBV)-specific cytotoxic cell bank for the treatment of EBV-associated lymphoproliferative disease.

    Science.gov (United States)

    Vickers, Mark A; Wilkie, Gwen M; Robinson, Nicolas; Rivera, Nadja; Haque, Tanzina; Crawford, Dorothy H; Barry, Jacqueline; Fraser, Neil; Turner, David M; Robertson, Victoria; Dyer, Phil; Flanagan, Peter; Newlands, Helen R; Campbell, John; Turner, Marc L

    2014-11-01

    Epstein-Barr virus (EBV) is associated with several malignancies, including post-transplant lymphoproliferative disorder (PTLD). Conventional treatments for PTLD are often successful, but risk organ rejection and cause significant side effects. EBV-specific cytotoxic T lymphocytes (CTLs) generated in vitro from peripheral blood lymphocytes provide an alternative treatment modality with few side effects, but autologous CTLs are difficult to use in clinical practice. Here we report the establishment and operation of a bank of EBV-specific CTLs derived from 25 blood donors with human leucocyte antigen (HLA) types found at high frequency in European populations. Since licensure, there have been enquiries about 37 patients, who shared a median of three class I and two class II HLA types with these donors. Cells have been infused into ten patients with lymphoproliferative disease, eight of whom achieved complete remission. Neither patient with refractory disease was matched for HLA class II. Both cases of EBV-associated non-haematopoietic sarcoma receiving cells failed to achieve complete remission. Thirteen patients died before any cells could be issued, emphasizing that the bank should be contacted before patients become pre-terminal. Thus, this third party donor-derived EBV-specific CTL cell bank can supply most patients with appropriately matched cells and most recipients have good outcomes.

  11. 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.

  12. Hypomethylation and Over-Expression of the Beta Isoform of BLIMP1 is Induced by Epstein-Barr Virus Infection of B Cells; Potential Implications for the Pathogenesis of EBV-Associated Lymphomas

    Directory of Open Access Journals (Sweden)

    Katerina Vrzalikova

    2012-10-01

    Full Text Available B-lymphocyte-induced maturation protein 1 (BLIMP1 exists as two major isoforms, α and β, which arise from alternate promoters. Inactivation of the full length BLIMP1α isoform is thought to contribute to B cell lymphomagenesis by blocking post-germinal centre (GC B cell differentiation. In contrast, the shorter β isoform is functionally impaired and over-expressed in several haematological malignancies, including diffuse large B cell lymphomas (DLBCL. We have studied the influence on BLIMP1β expression of the Epstein-Barr virus (EBV, a human herpesvirus that is implicated in the pathogenesis of several GC-derived lymphomas, including a subset of DLBCL and Hodgkin’s lymphoma (HL. We show that BLIMP1β expression is increased following the EBV infection of normal human tonsillar GC B cells. We also show that this change in expression is accompanied by hypomethylation of the BLIMP1β-specific promoter. Furthermore, we confirmed previous reports that the BLIMP1β promoter is hypomethylated in DLBCL cell lines and show for the first time that BLIMP1β is hypomethylated in the Hodgkin/Reed-Sternberg (HRS cells of HL. Our results provide evidence in support of a role for BLIMP1β in the pathogenesis of EBV-associated B cell lymphomas.

  13. Treatment options for post-transplantation diabetes mellitus.

    Science.gov (United States)

    Sharif, Adnan

    2015-01-01

    Treatment options for management of post-transplantation diabetes mellitus (PTDM) are limited with regards to the availability of strong clinical evidence base. This is a concern as PTDM is common after solid organ transplantation and associated with poor clinical outcomes. PTDM and type 2 diabetes mellitus are distinct pathophysiological entities that have important differences with regards to aetiology, clinical course and management. Therefore, any clinical evidence of treatment benefit from the general population with type 2 diabetes mellitus may not be directly translated to the solid organ transplant recipient. In addition, the potential risk and benefit of using many of these therapeutic agents must take account of the complicated post-transplantation milieu of immunosuppression. While there is reasonable evidence base for treatment of diabetes mellitus in the general population, the same is not true in a post-transplantation setting. In this article the treatment options available for PTDM will be discussed, with a transplant-specific focus on the pros and cons of each particular component of the glucose lowering therapy armoury.

  14. EB病毒相关淋巴增生性疾病的分类和治疗%Classification and treatment of EBV-associated lymphoproliferative disorders

    Institute of Scientific and Technical Information of China (English)

    王学文

    2009-01-01

    Since its discovery as the first human tumor associated virus, Epstein-Barr virus (EBV) has been implicated in the development of a wide range of B-cell lymphoproliferative disorders, including Burkitt' slymphoma, classic Hodgkin' s lymphoma and lymphomas arising in immunocompromised individuals (posttransplant and HIV-associated lymphoproliferative disorders). T-cell lymphoproliferative disorders that have been reported to be EBV associated include a subset of peripheral T-cell lymphomas, angioimmunoblastic T-cell lymphoma, extranodal nasal type natural killer/T-cell lymphoma, and other rare histotypes. EBV encodes a series of products interacting with or exhibiting homology to wide variety of antiapoptotic molecules,cytokines, and signal transducers, hence promoting EBV infection, immortalization and transformation.However, the exact mechanism by which EBV promotes oncogenesis is still an area of active debate. This review is focused on the pathology, diagnosis, classification, and pathogenesis of EBV-associated lymphomas.Recent advances in EBV cell-based immunotherapy, which is beginning to show promise in the treatment of EBV-related disorders, are discussed.%自从EB病毒(EBV)作为第一种人类肿瘤病毒被发现以来,EBV已涉及广泛的B细胞淋巴增生性疾病(LPD)的发生,包括伯基特(Burkitt)淋巴瘤、经典的霍奇金淋巴瘤(cHL)及免疫减损个体发生的淋巴瘤(移植后和HIV相关的LPD).EBV相关的T细胞LPD已有报道,包括外周T细胞淋巴瘤、血管性免疫母细胞性T细胞淋巴瘤及其他罕见的组织学类型.EBV编码一系列与之相互作用或同源的产物,它包括多种抗凋亡分子、细胞因子和信号转导蛋白,从而促进EBV感染、无限增生化(永生)和转化.EBV促发肿瘤的确切机制正在被活跃地思考和讨论中.文章重点综述EBV相关淋巴瘤的病理学、诊断、分类、发病学以及以EBV的细胞为基础的免疫治疗用于EBV相关疾病,后者在临床应用中已展示希望.

  15. Verotoxin targets lymphoma infiltrates of patients with post-transplant lymphoproliferative disease.

    Science.gov (United States)

    Arbus, G S; Grisaru, S; Segal, O; Dosch, M; Pop, M; Lala, P; Nutikka, A; Lingwood, C A

    2000-10-01

    Post-transplant lymphoproliferative disease (PTLD) is an invasive, EBV expressing B lymphoma and a major cause of morbidity and mortality following organ transplantation. Presently there is limited therapy available; rather the patient often loses the allograft or succumbs to the malignancy. CD77 (or globotriaosyl ceramide -Gb(3)) is a germinal center B cell marker [Gregory et al. Int J Cancer 1998;42:213-20; Gregory et al., J Immunol 1987;139:313-8; Mangeney et al. Eur J Immunol 1991;21:1131-40], expressed on most EBV infected B cells and is the receptor for the E. coli derived verotoxin (VT) [Lingwood CA. Advances in Lipid Research 1993;25:189-212]. We present the basis of a possible novel approach to PTLD therapy utilizing the specific targeting of VT to the infiltrating lymphoma cells. Biopsies of adenoid, kidney or liver tissue of four PTLD patients were stained with verotoxin to determine expression of CD77. VT is a potent inducer of necrosis/apoptosis of receptor positive cells. In each PTLD case, the infiltrating EBV positive B lymphoma cells were strongly and selectively stained with VT, identifying CD77 as a new marker for these cells. For such individuals, VT might provide the basis of an approach to control their malignancy.

  16. POST-TRANSPLANT LYMPHOPROLIFERATIVE DISORDERS: ROLE OF VIRAL INFECTION, GENETIC LESIONS AND ANTIGEN STIMULATION IN THE PATHOGENESIS OF THE DISEASE

    Directory of Open Access Journals (Sweden)

    Daniela Capello

    2009-11-01

    Full Text Available Post-transplant lymphoproliferative disorders (PTLD are a life-threatening complication of solid organ transplantation or, more rarely, hematopoietic stem cell transplantation. The majority of PTLD is of B-cell origin and associated with Epstein–Barr virus (EBV infection. PTLD generally display involvement of extranodal sites, aggressive histology and aggressive clinical behavior. The molecular pathogenesis of PTLD involves infection by oncogenic viruses, namely Epstein-Barr virus, as well as genetic or epigenetic alterations of several cellular genes. At variance with lymphoma arising in immunocompetent hosts, whose genome is relatively stable, a fraction of PTLD are characterized by microsatellite instability as a consequence of defects in the DNA mismatch repair mechanism. Apart from microsatellite instability, molecular alterations of cellular genes recognized in PTLD include alterations of cMYC, BCL6, TP53, DNA hypermethylation, and aberrant somatic hypermutation of protooncogenes. The occurrence of IGV mutations in the overwhelming majority of PTLD documents that malignant transformation targets germinal centre (GC B-cells and their descendants both in EBV–positive and EBV–negative cases. Analysis of phenotypic markers of B-cell histogenesis, namely BCL6, MUM1 and CD138, allows further distinction of PTLD histogenetic categories. PTLD expressing the BCL6+/MUM1+/-/CD138- profile reflect B-cells actively experiencing the GC reaction, and comprise diffuse large B-cell lymphoma (DLBCL centroblastic and Burkitt lymphoma. PTLD expressing the BCL6-/MUM1+/CD138- phenotype putatively derive from B-cells that have concluded the GC reaction, and comprise the majority of polymorphic PTLD and a fraction of DLBCL immunoblastic. A third group of PTLD is reminiscent of post-GC and preterminally differentiated B-cells that show the BCL6-/MUM1+/CD138+ phenotype, and are morphologically represented by either polymorphic PTLD or DLBCL immunoblastic.

  17. Epstein-Barr virus (EBV) association and latency profile in pediatric Burkitt's lymphoma: experience of a single institution in Argentina.

    Science.gov (United States)

    Lara, Julia; Cohen, Melina; De Matteo, Elena; Aversa, Luis; Preciado, Maria Victoria; Chabay, Paola

    2014-05-01

    The aim of this study is to characterize EBV expression and latency pattern in pediatric Burkitt's lymphoma in a single institution in Argentina. EBV-encoded RNA or protein was analyzed in 27 patients. EBERs was expressed in 37% of patients (29% of immunocompetent and 100% of immunosuppressed patients). EBV-positive cases were observed exclusively in patients younger than 5 years old. EBV association with immunocompetent patients exhibits the sporadic pattern in region under study, while its presence in patients infected with HIV was higher than described previously. EBV latency I profile was present in most of the patients, except for two immunosuppressed patients who displayed LMP1 expression.

  18. Epstein-Barr Virus-Negative Post-Transplant Lymphoproliferative Diseases: Three Distinct Cases from a Single Center

    Directory of Open Access Journals (Sweden)

    Şule Mine Bakanay

    2014-03-01

    Full Text Available Three cases of Epstein-Barr virus (EBV-negative post-transplant lymphoproliferative disease that occurred 6 to 8 years after renal transplantation are reported. The patients respectively had gastric mucosa-associated lymphoid tissue lymphoma, gastric diffuse large B-cell lymphoma, and atypical Burkitt lymphoma. Absence of EBV in the tissue samples was demonstrated by both in situ hybridization for EBV early RNA and polymerase chain reaction for EBV DNA. Patients were treated with reduction in immunosuppression and combined chemotherapy plus an anti-CD20 monoclonal antibody, rituximab. Despite the reduction in immunosuppression, patients had stable renal functions without loss of graft functions. The patient with atypical Burkitt lymphoma had an abnormal karyotype, did not respond to treatment completely, and died due to disease progression. The other patients are still alive and in remission 5 and 3 years after diagnosis, respectively. EBV-negative post-transplant lymphoproliferative diseases are usually late-onset and are reported to have poor prognosis. Thus, reduction in immunosuppression is usually not sufficient for treatment and more aggressive approaches like rituximab with combined chemotherapy are required.

  19. Epstein-barr virus-negative post-transplant lymphoproliferative diseases: three distinct cases from a single center.

    Science.gov (United States)

    Bakanay, Sule Mine; Kaygusuz, Gülşah; Topçuoğlu, Pervin; Sengül, Sule; Tunçalı, Timur; Keven, Kenan; Kuzu, Işınsu; Uysal, Akın; Arat, Mutlu

    2014-03-01

    Three cases of Epstein-Barr virus (EBV)-negative post-transplant lymphoproliferative disease that occurred 6 to 8 years after renal transplantation are reported. The patients respectively had gastric mucosa-associated lymphoid tissue lymphoma, gastric diffuse large B-cell lymphoma, and atypical Burkitt lymphoma. Absence of EBV in the tissue samples was demonstrated by both in situ hybridization for EBV early RNA and polymerase chain reaction for EBV DNA. Patients were treated with reduction in immunosuppression and combined chemotherapy plus an anti-CD20 monoclonal antibody, rituximab. Despite the reduction in immunosuppression, patients had stable renal functions without loss of graft functions. The patient with atypical Burkitt lymphoma had an abnormal karyotype, did not respond to treatment completely, and died due to disease progression. The other patients are still alive and in remission 5 and 3 years after diagnosis, respectively. EBV-negative post-transplant lymphoproliferative diseases are usually late-onset and are reported to have poor prognosis. Thus, reduction in immunosuppression is usually not sufficient for treatment and more aggressive approaches like rituximab with combined chemotherapy are required.

  20. Epstein-Barr virus-related post-transplant lymphoproliferative disorder occurring after bone marrow transplantation for aplastic anemia in Down's syndrome.

    Science.gov (United States)

    Furuya, Aya; Ishida, Mitsuaki; Hodohara, Keiko; Yoshii, Miyuki; Okuno, Hiroko; Horinouchi, Akiko; Nakanishi, Ryota; Harada, Ayumi; Iwai, Muneo; Yoshida, Keiko; Kagotani, Akiko; Yoshida, Takashi; Okabe, Hidetoshi

    2014-01-01

    It is well established that Down's syndrome exhibits a predisposition to development of leukemia, however, association between aplastic anemia and Down's syndrome is exceptional. Herein, we describe a case of aplastic anemia occurring in Down's syndrome following post-transplant lymphoproliferative disorder (PTLD) after bone marrow transplantation (BMT). A 27-year-old Japanese male with Down's syndrome presented with a headache. Laboratory tests revealed severe pancytopenia, and bone marrow biopsy demonstrated hypocellular bone marrow with decrease of trilineage cells, which led to a diagnosis of aplastic anemia. One year after diagnosis, he was incidentally found to have an anterior mediastinal tumor, which was histopathologically diagnosed as seminoma. Subsequently, he received BMT from a female donor, and engraftment was observed. Three months after transplantation, he experienced cough and high fever. Biopsy specimen from the lung revealed diffuse proliferation of large-sized lymphoid cells expressing CD20 and EBER. These lymphoid cells had XY chromosomes. Thus, a diagnosis of EBV-associated PTLD was made. This is the seventh documented case of aplastic anemia occurring in Down's syndrome. Association between aplastic anemia and Down's syndrome has not been established, therefore, additional clinicopathological studies are needed. Moreover, this is the first case to undergo BMT for aplastic anemia in Down's syndrome. Although engraftment was observed, he developed EBV-positive PTLD. The neoplastic cells of the present case were considered to be of recipient origin, although the majority of PTLD cases with BMT are of donor origin.

  1. Voriconazole-induced periostitis: beyond post-transplant patients.

    Science.gov (United States)

    Reber, Joshua D; McKenzie, Gavin A; Broski, Stephen M

    2016-06-01

    Voriconazole-induced periostitis (VIP) is a rare but increasingly encountered entity since Food and Drug Administration (FDA) approval of the second generation antifungal medication in 2002. Literature reports most commonly include transplant recipients on immunosuppressive therapy simultaneously requiring antifungal therapy. Nontransplant patients receiving long-term voriconazole have an equal risk of developing the disease, but may experience a delay in diagnosis due to a lack of familiarity with the process outside of the post-transplant and/or immunosuppressed population. We present a case of VIP in a nontransplant, immunocompetent patient on suppressive antifungal therapy for prior abdominal aortic stent graft fungal infection. Radiologist review of current medications and recognition of periostitis on multiple imaging modalities may hasten the diagnosis and lead to earlier treatment and resolution of symptoms.

  2. Post-transplant lymphoproliferative disorders of oral cavity.

    Science.gov (United States)

    Ojha, Junu; Islam, Nadim; Cohen, Donald M; Marshal, David; Reavis, Michael R; Bhattacharyya, Indraneel

    2008-05-01

    Post-transplant lymphoproliferative disorders (PTLD) are long-term complications of immunosuppression after solid organ/bone marrow transplantation. In most cases, PTLD arises as a result of primary or reactivated Epstein-Barr virus infection in a host with impaired cellular immunity. PTLD is most often seen in the gastrointestinal tract, although it has also been reported in other organ systems, including the central nervous system and, rarely, in the head and neck. It is characterized histologically by abnormal lymphoid cell proliferation. Although many forms of PTLD do not meet all of the histologic criteria of lymphoma, they often behave clinically in a malignant fashion if left untreated. We present 3 rare cases of PTLD manifesting in the oral cavity as mucosal masses after solid organ transplantation. There are only 8 published reports of PTLD in the literature presenting as oral lesions. The clinical, pathologic, and therapeutic spectra of PTLD are discussed.

  3. HSV-tk/GCV gene therapy mediated by EBV-LMP1 for EBV-associated cancer

    Directory of Open Access Journals (Sweden)

    Midan Ai

    2008-09-01

    Full Text Available Abstract Background To investigate the feasibility of gene therapy in treating Epstein-Barr virus (EBV-associated cancer by employing the suicide gene, herpes simplex virus thymidine kinase/ganciclovir (HSV-tk/GCV, which uses the signaling pathway through the HIV-long terminal repeat (LTR gene which is expressed from a nuclear factor-κB (NF-κB-binding motif-containing promoter that is regulated by EBV-latent membrane protein 1 (LMP1 via NF-κB. Methods First, we constructed the plasmid pVLTR-tk, which was regulated by EBV-LMP1 via NF-κB, and then investigated the cytotoxic effect of the pVLTR-tk/GCV on cancer cells, using MTT assays, clonogenic assays, flow cytometry, and animal experiments. Results The activation of TK was increased after transfection of the pVLTR-tk into the EBV-LMP1 positive cells. After GCV treatment, the clonogenicity and survival of the cells substantially declined, and a bystander effect was also observed. The LMP1 positive cells exhibited remarkable apoptosis following pVLTR-tk/GCV treatment, and the pVLTR-tk/GCV restrained tumor growth in vivo for EBV-LMP1 positive cancers. Conclusion The pVLTR-tk/GCV suicide gene system may be used as a new gene targeting strategy for EBV-associated cancer.

  4. A 5-year old male with “leukemic form” of disseminated post-transplant lymphoproliferative disorder

    Directory of Open Access Journals (Sweden)

    Saadiya Haque

    2010-03-01

    Full Text Available Post-transplant lymphoproliferative disorder (PTLD represents an abnormal lymphoid proliferation that occurs in recipients of solid organ or bone marrow allograft. It includes a diverse group of diseases ranging from polymorphic B-cell hyperplasia to frank malignant lymphoma. Clinical presentation is variable, ranging from asymptomatic to generalized lymphadenopathy, mononucleosis-like syndrome, nodal or extranodal tumors (usually gastrointestinal tract, systemic lymphomatous involvement, and rare (less than 1% of cases fulminant disseminated disease. PTLD is more common in children than in adults. Younger patients usually present with mononucleosis-like symptoms. We present an unusual case of a 5-year old male who developed a widely disseminated leukemic form of PTLD, involving lymph nodes, tonsils, multiple organs, bone marrow, cerebrospinal fluid, and peripheral blood.

  5. EBV-Induced Human CD8+ NKT Cells Synergize CD4+ NKT Cells Suppressing EBV-Associated Tumors upon Induction of Th1-Bias

    Institute of Scientific and Technical Information of China (English)

    Wei Xiao; Li Li; Rui Zhou; Ruijing Xiao; Yujuan Wang; Xiang Ji; Mengjun Wu; Lan Wang; Wei Huang; Xiaoling Zheng; Xinti Tan; Lang Chen; Tao Xiong; Jie Xiong; Youxin Jin; Jinquan Tan; Yuling He

    2009-01-01

    CD8+ natural killer T (NKT) cells from EBV-associated turnout patients are quantitatively and functionally impaired. EBV-induced CD8+ NKT cells drive syngeneic T cells into a Thl-bias response to suppress EBV-associated malignancies. IL-4-biased CD4+ NKT cells do not affect either syngeneic T cell cytotoxicity or Th cytokine secretion. Circulating mDC1 cells from patients with EBV-associated malignancies impair the production of IFN-γ by CD8+ NKT cells. In this study, we have established a human-thymus-SCID chimaera model to further investigate the underlying mechanism of EBV-induced CD8+ NKT cells in suppressing EBV-associated malignancies. In the human-thymus-SCID chimera, EBV-induced CD8+ NKT cells suppress EBV-associated malignancies in a manner dependent on the Th1-bias response and syngeneic CD3+ T cells. However, adoptive transfer with CD4+ NKT cells alone inhibits T cell immunity. Interestingly, CD4+ NKT cells themselves secrete high levels of IL-2, enhancing the persistence of adoptively transferred CD8+ NKT cells and T cells, thereby leading to a more pronounced T cell anti-tumour response in chimaeras co-transferred with CD4+ and CD8+ NKT cells. Thus, immune reconstitution with EBV-induced CD4+ and CD8+ NKT cells synergistically enhances T cell tumour immunity, providing a potential prophylactic and therapeutic treatment for EBV-associated malignancies. Cellular & Molecular Immunology. 2009;6(5):367-379.

  6. Epstein-Barr virus (EBV)-associated lymphoid lesions of the head and neck.

    Science.gov (United States)

    Auerbach, Aaron; Aguilera, Nadine S

    2015-01-01

    Epstein Barr virus (EBV)-related lymphoproliferative processes occur in the head and neck ranging from reactive processes such as infectious mononucleosis to high grade malignant lymphomas. EBV is a ubiquitous herpes virus that infects more than 90% of adults worldwide, and is generally transferred though saliva. Primary infection can occur throughout life. EBV is the first virus linked to malignancies, both epithelial and lymphoid. Both T and B cell lymphomas can be associated with EBV and evidence shows that an individual's response to the acute EBV infection may be critical in the development of subsequent lymphoma. Currently, in situ hybridization for EBER is the most sensitive available test to detect EBV and should be routinely performed in lymphoproliferative lesions of the head and neck. Immunohistochemistry for EBV related proteins, such as LMP1, is much less sensitive than EBER in situ hybridization, but can help determine latency patterns of EBV infection. Although relatively rare, primary EBV-related lymphomas must be considered in the differential of atypical lymphoid proliferations in the head and neck. We present selected EBV-related disorders of the head and neck discussing etiology as well as differential diagnosis.

  7. Early onset post-transplant lymphoproliferative disease is associated with allograft localization

    NARCIS (Netherlands)

    Bakker, NA; van Imhoff, GW; Verschuuren, EAM; van Son, WJ; van der Heide, JJH; Veeger, NJGM; Kluin, PM; Kluin-Nelemans, HC

    2005-01-01

    Post-transplant lymphoproliferative disease (PTLD) is a major complication after solid organ transplantation. We analyzed incidence, patient characteristics, clinical presentation, and prognostic factors for treatment outcome and survival of PTLD patients transplanted at our center. Records from adu

  8. Post-transplant lymphoproliferative disorder: Case reports of three children with kidney transplant

    Directory of Open Access Journals (Sweden)

    Spasojević-Dimitrijeva Brankica

    2014-01-01

    Full Text Available Introduction. Post-transplant lymphoproliferative disorder (PTLD is a heterogeneous group of diseases, characterized by abnormal lymphoid proliferation following transplantation. It is a disease of the immunosuppressed state, and its occurrence is mostly associated with the use of T-cell depleting agents, and also intensification of immunosuppressive regimens. In the majority of cases, PTLD is a consequence of Epstein-Barr virus (EBV infection and is a B-cell hyperplasia with CD-20 positive lymphocytes. The 2008 World Health Organization classification for lymphoid malignancies divides PTLD into four major categories: early lesions, polymorphic PTLD, monomorphic PTLD and Hodgkin PTLD. The treatment and prognosis depend on histology. The cornerstone of PTLD therapy includes reduction/withdrawal of immunosuppression, monoclonal anti CD-20 antibody (rituximab and chemotherapy. Outline of Cases. We reported here our experiences with three patients, two girls aged 7.5 and 15 and a 16-year old boy. They had different organ involvement: brain, combined spleen-liver and intestines, respectively. Even though EBV was a trigger of lymphoid proliferation as it was confirmed by histopathology or in cerebrospinal fluid, qualitative EBV-PCR was positive only in one patient at disease presentation. Reduction of immunosuppression therapy was applied in treatment of all three patients, while two of them received rituximab and ganciclovir. They had an excellent outcome besides many difficulties in diagnosis and management of disease. Conclusion. Qualitative EBV-PCR is not useful marker in pediatric transplant recipients. Our suggestion is that patients with the risk factors like T-cell depleting agents, immunosuppressant protocol or increasing immunosuppressive therapy and EBV miss-match with donor must be more accurately monitored with quantitative EBV PCR. [Projekat Ministarstva nauke Republike Srbije, br. 175085

  9. Cerebral Post-Transplant Lymphoproliferative Disorder Occurring after Renal Transplantation: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Suh, Jang Ho; Byun, Woo Mok; Kim, Hong Chul; Hwang, Min Su [Dept. of Radiology, Yeungnam University College of Medicine, Daegu (Korea, Republic of)

    2012-04-15

    Post-transplant lymphoproliferative disorder (PTLD) is a complication of organ transplantation and immunosuppression. A 36-year-old woman with a history of renal transplantation visited the hospital complaining of headache and on pathology was diagnosed with cerebral PTLD manifesting as multiple rim enhanced masses in both hemispheres. We report here a case of post-transplant lymphoproliferative disorder involving the cerebrum occurring after renal transplantation, and describe the MRI findings for this patient

  10. [Post-transplant lymphoproliferative disease in liver transplant recipients--Merkur University Hospital single center experience].

    Science.gov (United States)

    Filipec-Kanizaj, Tajana; Budimir, Jelena; Colić-Cvrlje, Vesna; Kardum-Skelin, Ika; Sustercić, Dunja; Naumovski-Mihalić, Slavica; Mrzljak, Anna; Kolonić, Slobodanka Ostojić; Sobocan, Nikola; Bradić, Tihomir; Dolić, Zrinka Misetić; Kocman, Branislav; Katicić, Miroslava; Zidovec-Lepej, Snjezana; Vince, Adriana

    2011-09-01

    Post-transplant lymphoproliferative disorder (PTLD) is an increasingly recognized condition as the number of solid organ and bone marrow transplant recipients increases. It can be a life threatening fulminant disorder and affects approximately 8% of solid organ transplant recipients. Epstein-Barr virus (EBV) is closely involved in the pathogenesis of PTLD and the majority of PTLD cases arise in response to primary infection with EBV or to re-activation of previously acquired EBV. The principal risk factors underlying the development of PTLD are the degree of overall immunosuppression and EBV serostatus of the recipient. The most commonly used pathologic classification of PTLD is the World Health Organization classification, which divides PTLD into three categories: early lesions, polymorphic PTLD, and monomorphic PTLD. Early lesions are characterized by reactive plasmacytic hyperplasia. Polymorphic PTLD may be either polyclonal or monoclonal and is characterized by destruction of the underlying lymphoid architecture, necrosis, and nuclear atypia. In monomorphic PTLD, the majority of cases (>80%) arise from B cells, similar to non-Hodgkin's lymphoma in immunocompetent hosts. The most common subtype is diffuse large B-cell lymphoma, but Burkitt's/Burkitt's-like lymphoma and plasma cell myeloma are also seen. Rarely T-cell variants occur, which include peripheral T-cell lymphomas and, rarely, other uncommon types, including gamma/delta T-cell lymphoma and T-natural killer (NK) cell varieties. Hodgkin's disease-like lymphoma is very unusual. An accurate diagnosis of PTLD requires a high index of suspicion, since the disorder may present subtly and/or extranodally. Radiologic evidence of a mass or the presence of elevated serum markers (such as increased LDH levels) are suggestive of PTLD, with positive finding on ultrasonography, computed tomography, magnetic resonance and/or positron emission tomography scanning (possibly indicating metabolically active areas) also

  11. POST-TRANSPLANT LYMPHOPROLIFERATIVE DISORDERS: ROLE OF VIRAL INFECTION, GENETIC LESIONS AND ANTIGEN STIMULATION IN THE PATHOGENESIS OF THE DISEASE

    Directory of Open Access Journals (Sweden)

    Gianluca Gaidano

    2009-11-01

    Full Text Available

    Post-transplant lymphoproliferative disorders (PTLD are a life-threatening complication of solid organ transplantation or, more rarely, hematopoietic stem cell transplantation. The majority of PTLD is of B-cell origin and associated with Epstein–Barr virus (EBV infection. PTLD generally display involvement of extranodal sites, aggressive histology and aggressive clinical behavior. The molecular pathogenesis of PTLD involves infection by oncogenic viruses, namely Epstein-Barr virus, as well as genetic or epigenetic alterations of several cellular genes. At variance with lymphoma arising in immunocompetent hosts, whose genome is relatively stable, a fraction of PTLD are characterized by microsatellite instability as a consequence of defects in the DNA mismatch repair mechanism. Apart from microsatellite instability, molecular alterations of cellular genes recognized in PTLD include alterations of cMYC, BCL6, TP53, DNA hypermethylation, and aberrant somatic hypermutation of protooncogenes. The occurrence of IGV mutations in the overwhelming majority of PTLD documents that malignant transformation targets germinal centre (GC B-cells and their descendants both in EBV–positive and EBV–negative cases. Analysis of phenotypic markers of B-cell histogenesis, namely BCL6, MUM1 and CD138, allows further distinction of PTLD histogenetic categories. PTLD expressing the BCL6+/MUM1+/-/CD138- profile reflect B-cells actively experiencing the GC reaction, and comprise diffuse large B-cell lymphoma (DLBCL centroblastic and Burkitt lymphoma. PTLD expressing the BCL6-/MUM1+/CD138- phenotype putatively derive from B-cells that have concluded the GC reaction, and comprise the majority of polymorphic PTLD and a fraction of

  12. B Cell Function in Severe Combined Immunodeficiency after Stem Cell or Gene Therapy: A Review

    Science.gov (United States)

    Buckley, Rebecca H.

    2010-01-01

    While bone marrow transplantation has resulted in life-saving T cell reconstitution in infants with severe combined immunodeficiency (SCID), correction of B cell function has been more problematic. This review examines B cell reconstitution results presented in 19 reports from the United States and Europe on post-transplantation immune reconstitution in SCID over the past two decades. The analysis considered whether pre-transplantation conditioning regimens were used, the overall survival rate, the percentage with donor B cell chimerism, the percentage with B cell function, and the percentage of survivors requiring immunoglobulin (IG) replacement. The survival rates were higher at those Centers that did not use pre-transplant conditioning or post-transplantation graft-versus-host disease prophylaxis. The percentage of survivors with B cell chimerism and/or function was higher and the percentage requiring IG replacement was lower at those Centers that used pre-transplant conditioning. However there were substantial numbers of patients requiring IG replacement at all Centers. Thus, pre-transplant conditioning does not guarantee that B cell function will develop. Since most infants with SCID either present with serious infections or are diagnosed as newborns, one must decide whether there is justification for using agents that compromise innate immunity and have intrinsic toxicities to gain B cell immune reconstitution. PMID:20371393

  13. Minimal Residual Disease Diagnostics and Chimerism in the Post-Transplant Period in Acute Myeloid Leukemia

    Directory of Open Access Journals (Sweden)

    Ulrike Bacher

    2011-01-01

    Full Text Available In acute myeloid leukemia (AML, the selection of poor-risk patients for allogeneic hematopoietic stem cell transplantation (HSCT is associated with rather high post-transplant relapse rates. As immunotherapeutic intervention is considered to be more effective before the cytomorphologic manifestation of relapse, post-transplant monitoring gains increasing attention in stem cell recipients with a previous diagnosis of AML. Different methods for detection of chimerism (e.g., microsatellite analysis or quantitative real-time PCR are available to quantify the ratio of donor and recipient cells in the post-transplant period. Various studies demonstrated the potential use of mixed chimerism kinetics to predict relapse of the AML. CD34+-specific chimerism is associated with a higher specificity of chimerism analysis. Nevertheless, a decrease of donor cells can have other causes as well. Therefore, efforts continue to introduce minimal residual disease (MRD monitoring based on molecular mutations in the post-transplant period. The NPM1 (nucleophosmin mutations can be monitored by sensitive quantitative real-time PCR in subsets of stem cell recipients with AML, but for approximately 20% of patients, suitable molecular mutations for post-transplant MRD monitoring are not available so far. This emphasizes the need for an expansion of the panel of MRD markers in the transplant setting.

  14. Post-Transplant Recurrence of Hepatocellular Carcinoma and Elevated NLR

    Science.gov (United States)

    Rustagi, Tarun

    2010-01-01

    interest in the systemic proinflammatory effects exerted by tumors. Several inflammatory markers such as C-reactive protein and neutrophil-lymphocyte ratio (NLR) have been suggested as surrogate markers of tumor biology. NLR is one such marker of inflammation that has been linked with several malignancies. NLR >5 has been shown to be a marker of survival in colorectal cancer patients. Similarly, a few studies have demonstrated the efficacy of NLR in predicting outcome in patients undergoing liver resection for HCC; however, none directly compared the incidence of elevated NLR in LT patients with and without HCC recurrence. Our study results indicate no statistical difference in incidence of elevated NLR between the two groups. We suggest that elevated NLR might not be closely correlated to recurrence of HCC post-transplant, although the small sample size might be a limiting factor. Larger studies are necessary to more definitively evaluate this relationship.

  15. Cellular Immunotherapy Following Chemotherapy in Treating Patients With Recurrent Non-Hodgkin Lymphomas, Chronic Lymphocytic Leukemia or B-Cell Prolymphocytic Leukemia

    Science.gov (United States)

    2016-07-29

    Post-transplant Lymphoproliferative Disorder; B-Cell Prolymphocytic Leukemia; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell 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 Small Lymphocytic Lymphoma; Refractory Chronic Lymphocytic Leukemia; Refractory Hairy Cell Leukemia; B-Cell Lymphoma, Unclassifiable, With Features Intermediate Between Diffuse Large B-Cell Lymphoma and Burkitt Lymphoma; B-Cell Lymphoma, Unclassifiable, With Features Intermediate Between Diffuse Large B-Cell Lymphoma and Classical Hodgkin Lymphoma; Recurrent Lymphoplasmacytic Lymphoma

  16. Combined immunodeficiency and Epstein-Barr virus-induced B cell malignancy in humans with inherited CD70 deficiency

    DEFF Research Database (Denmark)

    Abolhassani, Hassan; Edwards, Emily S. J.; Ikinciogullari, Aydan

    2017-01-01

    is a novel cause of combined immunodeficiency and EBV-associated diseases, reminiscent of inherited CD27 deficiency. Overall, human CD70-CD27 interactions therefore play a nonredundant role in T and B cell-mediated immunity, especially for protection against EBV and humoral immunity.......In this study, we describe four patients from two unrelated families of different ethnicities with a primary immunodeficiency, predominantly manifesting as susceptibility to Epstein-Barr virus (EBV)-related diseases. Three patients presented with EBV-associated Hodgkin's lymphoma...... and hypogammaglobulinemia; one also had severe varicella infection. The fourth had viral encephalitis during infancy. Homozygous frameshift or in-frame deletions in CD70 in these patients abolished either CD70 surface expression or binding to its cognate receptor CD27. Blood lymphocyte numbers were normal...

  17. Genome-wide analysis of Epstein-Barr virus (EBV) isolated from EBV-associated gastric carcinoma (EBVaGC).

    Science.gov (United States)

    Liu, Ying; Yang, Wenjun; Pan, Yaqi; Ji, Jiafu; Lu, Zheming; Ke, Yang

    2016-01-26

    Epstein-Barr virus (EBV) is linked to the development of a variety of malignancies, including EBV-associated gastric carcinoma (EBVaGC). In this study, EBVaGC was detected in 15 (7.3%) of 206 GC cases. To identify the EBV genomic variation, EBV genomic sequences isolated from 9 EBVaGC biopsy specimens were successfully retrieved, designated EBVaGC1 to EBVaGC9. By comparative analysis of these strains with another 6 completely sequenced EBV strains, EBV-wild type, B95-8, AG876, GD1, GD2, and HKNPC1, it was demonstrated that EBVaGC1 to 9 were most closely related to the GD1 strain. Phylogenetic analysis of the GC biopsy specimen-derived EBV (GC-EBV) genomes was subsequently performed to assess their genomic diversity and it exhibited the greatest divergence from the type 2 strain, AG876. Compared with the reference EBV strain GD1, they harbored 961 variations in total, including 919 substitutions, 23 insertions, and 19 deletions. Single nucleotide polymorphism (SNP) density varied substantially across all known open reading frames and was highest in latency-associated genes. Moreover, we identified 2 interstrain recombinants at the EBNA1 locus, which provided a further mechanism for the generation of diversity. Some T-cell epitope sequences in EBNA1 and LMP2A genes showed extensive variation across strains, which implied their importance in the development of vaccines and T-cell therapy. In conclusion, we reported the first genome-wide view of sequence variation of EBV isolated from primary EBVaGC biopsy specimens, which might serve as an effective method for further understanding the genomic variations contribute to EBVaGC carcinogenesis and treatment.

  18. Carcinoma of the tongue in a renal transplant recipient: A rare post-transplant malignancy

    Directory of Open Access Journals (Sweden)

    Jai Prakash

    2015-01-01

    Full Text Available Current immunosuppression improved long-term outcome of transplant patients, but it also increased the incidence of de novo malignancy. Organ transplant recipients have a threeto four-fold increased risk of developing carcinoma in comparison with the general population. Common malignancies encountered after transplantation include cancer of the skin, lips, post-transplant lymphoproliferative disease, ano-genital carcinoma and Kaposi sarcoma. Squamous cell carcinoma of the tongue is very rare. We report here a case of squamous cell carcinoma of the tongue in an adult male patient who developed it 11 years post-transplant. He underwent right hemiglossectomy and his graft function remained stable.

  19. Three different histological subtypes of Epstein-Barr virus-negative post-transplant lymphoproliferative disorder in a patient with hepatitis C infection.

    Science.gov (United States)

    Kobayashi, Mikiko; Asano, Naoko; Fukushima, Mana; Honda, Takayuki

    2014-09-01

    We report a rare case in which Epstein-Barr virus (EBV)-negative polymorphic B-cell post-transplant lymphoproliferative disorder (PTLD) and EBV-negative monomorphic T-cell PTLD [anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma (ALCL)] were observed simultaneously in the same cervical lymph node, 34 months after liver transplantation for hepatitis C liver cirrhosis. Although hepatitis C recurred after 2 months, he had no other complications until PTLD occurred 34 months post-transplantation. The patient underwent reduction of the immunosuppressive drug and rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone therapy, and he was considered to have achieved complete remission. However, PTLD recurred, and he died 6 months after the initial diagnosis. Autopsy revealed only EBV-negative monomorphic T-cell PTLD (ALK-negative ALCL) that involved the liver, spleen, bilateral kidneys, stomach, bladder, heart, bone marrow, right ureter, and pons. Thus, recurrent PTLD may show a different histological type from the primary disorder, as PTLD has a multiclonal potentiality that causes various types of lymphomas. Therefore, it may be difficult to predict PTLD-related prognosis from the initial PTLD histological identification.

  20. Acute cellular rejection is a risk factor for bronchiolitis obliterans syndrome independent of post-transplant baseline FEV1

    DEFF Research Database (Denmark)

    Burton, C.M.; Iversen, M.; Carlsen, J.

    2009-01-01

    BACKGROUND: Post-transplant baseline forced expiratory volume in 1 second (FEV(1)) constitutes a systematic bias in analyses of bronchiolitis obliterans syndrome (BOS). This retrospective study evaluates risk factors for BOS adjusting for the confounding of post-transplant baseline FEV(1). METHODS...

  1. Yttrium Y 90 Ibritumomab Tiuxetan and Rituximab in Treating Patients With Post-Transplant Lymphoproliferative Disorder

    Science.gov (United States)

    2013-01-24

    Post-transplant Lymphoproliferative Disorder; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Stage III Adult Burkitt Lymphoma; Stage III Adult Diffuse Large Cell Lymphoma; Stage IV Adult Burkitt Lymphoma; Stage IV Adult Diffuse Large Cell Lymphoma; Waldenström Macroglobulinemia

  2. Post-transplant Lymphoproliferative disorder in the United States : Young Caucasian males are at highest risk

    NARCIS (Netherlands)

    Dharnidharka, VR; Tejani, AH; Ho, PL; Harmon, WE

    2002-01-01

    We have previously documented Caucasian race and cadaver donor source as risk factors for post-transplant lymphoproliferative disorder (PTLD) development in recipients registered in the North American Pediatric Renal Transplant Cooperative Study (NAPRTCS). We analyzed data from the Scientific Regist

  3. The risk factors of post-transplant lymphoproliferative disorders following haploidentical hematopoietic stem cell transplantation

    Institute of Scientific and Technical Information of China (English)

    张春丽

    2014-01-01

    Objective Post-transplant lymphoproliferative disorder(PTLD)occurring after allogeneic hematopoietic stem cell transplantation(allo-HSCT)is rare but severe.Risk factors including pre-HSCT exposure variables,conditioning regimens,transplant-related complications,and post-HSCT immune reconstitution were investigated in the development of PTLD after allo-HSCT.Methods A

  4. The role of diet and physical activity in post-transplant weight gain after renal transplantation

    NARCIS (Netherlands)

    Zelle, Dorien M.; Kok, Trijntje; Dontje, Manon L.; Danchell, Eva I.; Navis, Gerjan; van Son, Willem J.; Bakker, Stephan J. L.; Corpeleijn, Eva

    2013-01-01

    Background Long-term survival of renal transplant recipients (RTR) has not improved over the past 20yr. The question rises to what extent lifestyle factors play a role in post-transplant weight gain and its associated risks after transplantation. Methods Twenty-six RTR were measured for body weight,

  5. B cell helper assays.

    Science.gov (United States)

    Abrignani, Sergio; Tonti, Elena; Casorati, Giulia; Dellabona, Paolo

    2009-01-01

    Activation, proliferation and differentiation of naïve B lymphocytes into memory B cells and plasma cells requires engagement of the B cell receptor (BCR) coupled to T-cell help (1, 2). T cells deliver help in cognate fashion when they are activated upon recognition of specific MHC-peptide complexes presented by B cells. T cells can also deliver help in a non-cognate or bystander fashion, when they do not find specific MHC-peptide complexes on B cells and are activated by alternative mechanisms. T-cell dependent activation of B cells can be studied in vitro by experimental models called "B cell helper assays" that are based on the co-culture of B cells with activated T cells. These assays allow to decipher the molecular bases for productive T-dependent B cell responses. We show here examples of B cell helper assays in vitro, which can be reproduced with any subset of T lymphocytes that displays the appropriate helper signals.

  6. Characterization of variants in the promoter of BZLF1 gene of EBV in nonmalignant EBV-associated diseases in Chinese children

    Directory of Open Access Journals (Sweden)

    Yang Shuang

    2010-05-01

    Full Text Available Abstract Background Diseases associated with Epstein-Barr virus (EBV infections, such as infectious mononucleosis (IM, EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH and chronic active EBV infection (CAEBV are not rare in Chinese children. The association of type 1 or type 2 EBV and variants of the EBV BZLF1 promoter zone (Zp with these diseases is unclear. Results The objective of this study was to investigate the relationship between EBV genotypes (Zp variants and EBV type 1 and 2 and the clinical phenotypes of EBV-associated diseases in Chinese children. The Zp region was directly sequenced in 206 EBV-positive DNA samples from the blood of patients with IM, EBV-HLH, CAEBV, and healthy controls. Type 1 or type 2 EBV was examined by PCR for EBNA2 and EBNA3C subtypes. Four polymorphic Zp variants were identified: Zp-P, Zp-V3, Zp-P4 and Zp-V1, a new variant. The Zp-V3 variant was significantly associated with CAEBV (P ≤ 0.01. The frequency of co-infection with Zp variants was higher in patients with CAEBV and EBV-HLH, compared with IM and healthy controls, mostly as Zp-P+V3 co-infection. Type 1 EBV was predominant in all categories (81.3-95% and there was no significant difference in the frequency of the EBV types 1 and 2 in different categories (P > 0.05. Conclusions Type 1 EBV and BZLF1 Zp-P of EBV were the predominant genotypes in nonmalignant EBV associated diseases in Chinese children and Zp-V3 variant may correlates with the developing of severe EBV infection diseases, such as CAEBV and EBV-HLH.

  7. New concepts and best practices for management of pre- and post-transplantation cancer.

    Science.gov (United States)

    Campistol, Josep M; Cuervas-Mons, Valentín; Manito, Nicolás; Almenar, Luis; Arias, Manuel; Casafont, Fernando; Del Castillo, Domingo; Crespo-Leiro, María G; Delgado, Juan F; Herrero, J Ignacio; Jara, Paloma; Morales, José M; Navarro, Mercedes; Oppenheimer, Federico; Prieto, Martín; Pulpón, Luis A; Rimola, Antoni; Román, Antonio; Serón, Daniel; Ussetti, Piedad

    2012-10-01

    Solid-organ transplant recipients are at increased risk of developing cancer compared with the general population. Tumours can arise de novo, as a recurrence of a preexisting malignancy, or from the donated organ. The ATOS (Aula sobre Trasplantes de Órganos Sólidos; the Solid-Organ Transplantation Working Group) group, integrated by Spanish transplant experts, meets annually to discuss current advances in the field. In 2011, the 11th edition covered a range of new topics on cancer and transplantation. In this review we have highlighted the new concepts and best practices for managing cancer in the pre-transplant and post-transplant settings that were presented at the ATOS meeting. Immunosuppression plays a major role in oncogenesis in the transplant recipient, both through impaired immunosurveillance and through direct oncogenic activity. It is possible to transplant organs obtained from donors with a history of cancer as long as an effective minimization of malignancy transmission strategy is followed. Tumour-specific wait-periods have been proposed for the increased number of transplantation candidates with a history of malignancy; however, the patient's individual risk of death from organ failure must be taken into consideration. It is important to actively prevent tumour recurrence, especially the recurrence of hepatocellular carcinoma in liver transplant recipients. To effectively manage post-transplant malignancies, it is essential to proactively monitor patients, with long-term intensive screening programs showing a reduced incidence of cancer post-transplantation. Proposed management strategies for post-transplantation malignancies include viral monitoring and prophylaxis to decrease infection-related cancer, immunosuppression modulation with lower doses of calcineurin inhibitors, and addition of or conversion to inhibitors of the mammalian target of rapamycin. Copyright © 2012. Published by Elsevier Inc.

  8. AB95. Epidemiology of post-transplant malignancy in Chinese renal transplant recipients

    OpenAIRE

    Zhang, Jian; Ma, Linlin; Xie, Zelin; Guo, Yuwen; Sun, Wen; Zhang, Lei; Lin, Jun; Xiao, Jing; Zhu, Yichen; Tian, Ye

    2014-01-01

    Objective To investigate the incidence and types of post-transplant malignancy in Chinese renal transplant recipients. Methods We searched the CNKI and the Wanfang Data Knowledge Service Platform using the keywords “renal transplantation” and “malignancy” in Chinese. Data from 3,462 patients who underwent renal transplantation at Beijing Friendship Hospital were combined with data from 26 previous reports describing malignancy rates in 27,170 Chinese renal transplant recipients. Results The c...

  9. Post-transplant Lymphoproliferative Disorder Arising from Renal Allograft Parenchyma: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Park, Byung Kwan; Kim, Chan Kyo; Kwon, Ghee Young [Samsung Medical Center, Sungkyunkwan University College of Medicine, Seoul (Korea, Republic of)

    2010-06-15

    Post-transplant lymphoproliferative disorder (PTLD) is a rare but serious complication that occurs in patients undergoing kidney transplantation. PTLD usually manifests as a renal hilar mass comprised of histologically B-lymphocytes. We report our experience of managing a patient with PTLD arising from renal parenchyma. Ultrasonographic and MR imaging features of this unusual PTLD suggested differentiated renal cell carcinoma arising from the renal allograft

  10. CCL2 gene polymorphism is associated with post-transplant diabetes mellitus.

    Science.gov (United States)

    Dabrowska-Zamojcin, Ewa; Romanowski, Maciej; Dziedziejko, Violetta; Maciejewska-Karlowska, Agnieszka; Sawczuk, Marek; Safranow, Krzysztof; Domanski, Leszek; Pawlik, Andrzej

    2016-03-01

    Post-transplant diabetes mellitus (PTDM) is a common complication after solid organ transplantation, especially in recipients treated with calcineurin inhibitors. Previous studies suggest that chronic inflammation and chemokines play an important role in the pathogenesis of diabetes. Single-nucleotide polymorphisms (SNPs) can increase or decrease transcriptional activity and can change the production of chemokines. The aim of this study was to examine the association between CCL2 and CCL5 gene polymorphisms and the development of post-transplant diabetes mellitus. The study included 315 patients who received kidney transplants and were treated with calcineurin inhibitors. Patients were divided into two subgroups: with PTDM (n=43) and without PTDM (n=272). An additive model of univariate Cox regression analysis showed that the hazard of PTDM development was significantly positively associated with the number of CCL2 rs1024611 G alleles (HR 1.65; 95%CI 1.08-2.53; p=0.021). Multivariate Cox regression analysis, taking into the account the recipient's sex, age and BMI, as well as the number of G alleles of the CCL2 rs1024611 polymorphism, revealed that this polymorphism is an independent risk factor for post-transplant diabetes. The results of our study suggest an association between the CCL2 gene rs1024611 G allele and PTDM in patients treated with tacrolimus or cyclosporine.

  11. Clinical relevance of post-transplant pharmacodynamic analysis of cyclosporine in renal transplantation.

    Science.gov (United States)

    Kurata, Yoko; Kuzuya, Takafumi; Miwa, Yuko; Iwasaki, Kenta; Haneda, Masataka; Amioka, Katsuo; Yamada, Kiyofumi; Watarai, Yoshihiko; Katayama, Akio; Uchida, Kazuharu; Kobayashi, Takaaki

    2014-10-01

    Although therapeutic drug monitoring based on blood concentration has been widely implemented in transplant recipients treated with immunosuppressive agents, clinical adverse events such as rejection, infection or drug-induced toxicity caused by inappropriate dosage cannot be completely controlled. Development of an effective assay for optimized immunosuppression would be desirable, which can potentially lead to personalized medicine in renal transplantation. Cyclosporine (CSA) pharmacodynamic analysis using carboxyfluorescein diacetate succinimidyl ester (CFSE)-based T cell proliferation assay was examined in 66 kidney transplant recipients before and after transplantation. Two parameters, the 50% inhibitory concentration (IC50) and the percentage of T-cell proliferation values at the lower plateau (bottom), were compared with clinical events. A significant relation in CSA pharmacodynamic parameters was observed between pre- and post-transplantation. Analysis of the association between clinical outcomes and pharmacodynamic parameters in post-transplant samples demonstrated the following findings: (i) cytomegalovirus (CMV)/varicella zoster virus (VZV) reactivation and CSA-induced nephrotoxicity were significantly associated with high sensitivity to CSA (low bottom or low IC50), (ii) acute T cell-mediated rejection (ATMR) was significantly related to low sensitivity to CSA (high bottom), and (iii) de novo human leukocyte antigen (HLA) antibody production was associated with lower bottom and IC50 values, although the elucidation of those mechanisms is still in progress. It was suggested that CSA pharmacodynamics applied at post-transplantation would be useful for optimizing immunosuppressive therapy. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Post-Transplant Outcomes in High-Risk Compared with Non-High-Risk Multiple Myeloma: A CIBMTR Analysis.

    Science.gov (United States)

    Scott, Emma C; Hari, Parameswaran; Sharma, Manish; Le-Rademacher, Jennifer; Huang, Jiaxing; Vogl, Dan; Abidi, Muneer; Beitinjaneh, Amer; Fung, Henry; Ganguly, Siddhartha; Hildebrandt, Gerhard; Holmberg, Leona; Kalaycio, Matt; Kumar, Shaji; Kyle, Robert; Lazarus, Hillard; Lee, Cindy; Maziarz, Richard T; Meehan, Kenneth; Mikhael, Joseph; Nishihori, Taiga; Ramanathan, Muthalagu; Usmani, Saad; Tay, Jason; Vesole, David; Wirk, Baldeep; Yared, Jean; Savani, Bipin N; Gasparetto, Cristina; Krishnan, Amrita; Mark, Tomer; Nieto, Yago; D'Souza, Anita

    2016-10-01

    Conventional cytogenetics and interphase fluorescence in situ hybridization (FISH) identify high-risk multiple myeloma (HRM) populations characterized by poor outcomes. We analyzed these differences among HRM versus non-HRM populations after upfront autologous hematopoietic cell transplantation (autoHCT). Between 2008 and 2012, 715 patients with multiple myeloma identified by FISH and/or cytogenetic data with upfront autoHCT were identified in the Center for International Blood and Marrow Transplant Research database. HRM was defined as del17p, t(4;14), t(14;16), hypodiploidy (day 100 post-transplant, at least a very good partial response was 59% in HRM and 61% in non-HRM (P = .6). More HRM patients received post-transplant therapy with bortezomib and imids (26% versus 12%, P = .004). Three-year post-transplant progression-free (PFS) and overall survival (OS) rates in HRM versus non-HRM were 37% versus 49% (P post-transplant therapy was 46% (95% confidence interval [CI], 33 to 59) versus 14% (95% CI, 4 to 29) and in non-HRM patients with and without post-transplant therapy 55% (95% CI, 49 to 62) versus 39% (95% CI, 32 to 47); rates of OS for HRM patients with and without post-transplant therapy were 81% (95% CI, 70 to 90) versus 48% (95% CI, 30 to 65) compared with 88% (95% CI, 84 to 92) and 79% (95% CI, 73 to 85) in non-HRM patients with and without post-transplant therapy, respectively. Among patients receiving post-transplant therapy, there was no difference in OS between HRM and non-HRM (P = .08). In addition to HRM, higher stage, less than a CR pretransplant, lack of post-transplant therapy, and African American race were associated with worse OS. In conclusion, we show HRM patients achieve similar day 100 post-transplant responses compared with non-HRM patients, but these responses are not sustained. Post-transplant therapy appeared to improve the poor outcomes of HRM.

  13. Spontaneous Post-Transplant Disorders in NOD.Cg- Prkdcscid Il2rgtm1Sug/JicTac (NOG Mice Engrafted with Patient-Derived Metastatic Melanomas.

    Directory of Open Access Journals (Sweden)

    Enrico Radaelli

    Full Text Available Patient-derived tumor xenograft (PDTX approach is nowadays considered a reliable preclinical model to study in vivo cancer biology and therapeutic response. NOD scid and Il2rg-deficient mice represent the "gold standard" host for the generation of PDTXs. Compared to other immunocompromised murine lines, these mice offers several advantages including higher engraftment rate, longer lifespan and improved morphological and molecular preservation of patient-derived neoplasms. Here we describe a spectrum of previously uncharacterized post-transplant disorders affecting 14/116 (12% NOD.Cg- Prkdcscid Il2rgtm1Sug/JicTac (NOG mice subcutaneously engrafted with patient-derived metastatic melanomas. Affected mice exhibited extensive scaling/crusting dermatitis (13/14 associated with emaciation (13/14 and poor/unsuccessful tumor engraftment (14/14. In this context, the following pathological conditions have been recognized and characterized in details: (i immunoinflammatory disorders with features of graft versus host disease (14/14; (ii reactive lymphoid infiltrates effacing xenografted tumors (8/14; (iii post-transplant B cell lymphomas associated with Epstein-Barr virus reactivation (2/14. We demonstrate that all these entities are driven by co-transplanted human immune cells populating patient-derived tumor samples. Since the exploding interest in the utilization of NOD scid and Il2rg-deficient mice for the establishment of PDTX platforms, it is of uppermost importance to raise the awareness of the limitations associated with this model. The disorders here described adversely impact tumor engraftment rate and animal lifespan, potentially representing a major confounding factor in the context of efficacy and personalized therapy studies. The occurrence of these conditions in the NOG model reflects the ability of this mouse line to promote efficient engraftment of human immune cells. Co-transplanted human lymphoid cells have indeed the potential to

  14. Identification of a sub-population of B cells that proliferates after infection with epstein-barr virus

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    Ye Jianjiang

    2011-02-01

    Full Text Available Abstract Background Epstein-Barr virus (EBV-driven B cell proliferation is critical to its subsequent persistence in the host and is a key event in the development of EBV-associated B cell diseases. Thus, inquiry into early cellular events that precede EBV-driven proliferation of B cells is essential for understanding the processes that can lead to EBV-associated B cell diseases. Methods Infection with high titers of EBV of mixed, primary B cells in different stages of differentiation occurs during primary EBV infection and in the setting of T cell-immunocompromise that predisposes to development of EBV-lymphoproliferative diseases. Using an ex vivo system that recapitulates these conditions of infection, we correlated expression of selected B cell-surface markers and intracellular cytokines with expression of EBV latency genes and cell proliferation. Results We identified CD23, CD58, and IL6, as molecules expressed at early times after EBV-infection. EBV differentially infected B cells into two distinct sub-populations of latently infected CD23+ cells: one fraction, marked as CD23hiCD58+IL6- by day 3, subsequently proliferated; another fraction, marked as CD23loCD58+, expressed IL6, a B cell growth factor, but failed to proliferate. High levels of LMP1, a critical viral oncoprotein, were expressed in individual CD23hiCD58+ and CD23loCD58+ cells, demonstrating that reduced levels of LMP1 did not explain the lack of proliferation of CD23loCD58+ cells. Differentiation stage of B cells did not appear to govern this dichotomy in outcome either. Memory or naïve B cells did not exclusively give rise to either CD23hi or IL6-expressing cells; rather memory B cells gave rise to both sub-populations of cells. Conclusions B cells are differentially susceptible to EBV-mediated proliferation despite expression of viral gene products known to be critical for continuous B cell growth. Cellular events, in addition to viral gene expression, likely play a

  15. Post-transplant diabetes mellitus in lung transplant recipients: incidence and risk factors.

    Science.gov (United States)

    Ollech, Jacob E; Kramer, Mordechai R; Peled, Nir; Ollech, Ayelet; Amital, Anat; Medalion, Benjamin; Saute, Milton; Shitrit, David

    2008-05-01

    Post-transplant diabetes mellitus (PTDM) is a common and potentially serious complication after solid organ transplantation. There are only a few data, however, about the incidence of DM in patients undergoing lung transplantation. The medical records of 119 consecutive patients who underwent lung transplantation from 1998 to September 2004 were reviewed. Patients were divided in three groups according to their diabetes status, including pre-transplant DM, the PTDM group and those without DM. Patient records and all laboratory data were reviewed and the clinical course of diabetes was monitored. All recipients were treated with tacrolimus based regimen. Mean follow-up for all patients was 25+/-10. Twenty-three patients had DM in the pre-lung transplantation (LTX) DM group. PTDM developed in 34 of the remaining 96 patients (35.4%) with an incidence of 20%, 23% after 6 months and 12 months post-transplant. No significant difference was noted between 12 and 24 months post-LTX. The patients who developed DM were older (57+/-15 vs 53+/-13 years, p=0.009), had increased BMI (26+/-5 vs 24+/-4, p=0.0001), shorter time from diagnosis to LTX (21+/-13 vs 28+/-18 months, p=0.007) more cytomegalovirus infection and more acute rejection and hyperglycemia in the first month after LTX. Four patients died in the PTDM group compared to nine patients in the no-DM group (12% vs 14%; p=0.72). Post-transplant diabetes is a common complication in lung transplant patients receiving tacrolimus-based immunosuppression. The risk for developing PTDM is greatest among older recipients, those obese, and among recipients with more rejections episodes.

  16. Myoglobinuria masquerading as acute rejection in a renal allograft recipient with recurrent post transplant diabetic nephropathy.

    Science.gov (United States)

    Gupta, Pallav; Sharma, Amit; Khullar, Dinesh

    2014-08-01

    Rhabdomyolysis contributes to 7-10% of total AKI cases. Myoglobinuria as a cause of acute renal allograft dysfunction is extremely uncommon. Renal allograft recipient on cyclosporine or tacrolimus can develop myoglobinuria in presence of other precipitating factors. Present case describes an interesting report of myoglobinuria in a patient with post transplant diabetic nephropathy mimicking acute graft rejection. Clinically myoglobinuria presenting as renal allograft dysfunction is diagnosis of exclusion and renal biopsy is extremely important in making a correct diagnosis and planning optimal management in such cases.

  17. Loss-of-function mutations within the IL-2 inducible kinase ITK in patients with EBV-associated lymphoproliferative diseases.

    Science.gov (United States)

    Linka, R M; Risse, S L; Bienemann, K; Werner, M; Linka, Y; Krux, F; Synaeve, C; Deenen, R; Ginzel, S; Dvorsky, R; Gombert, M; Halenius, A; Hartig, R; Helminen, M; Fischer, A; Stepensky, P; Vettenranta, K; Köhrer, K; Ahmadian, M R; Laws, H-J; Fleckenstein, B; Jumaa, H; Latour, S; Schraven, B; Borkhardt, A

    2012-05-01

    The purpose of this study was the appraisal of the clinical and functional consequences of germline mutations within the gene for the IL-2 inducible T-cell kinase, ITK. Among patients with Epstein-Barr virus-driven lymphoproliferative disorders (EBV-LPD), negative for mutations in SH2D1A and XIAP (n=46), we identified two patients with R29H or D500T,F501L,M503X mutations, respectively. Human wild-type (wt) ITK, but none of the mutants, was able to rescue defective calcium flux in murine Itk(-/-) T cells. Pulse-chase experiments showed that ITK mutations lead to varying reductions of protein half-life from 25 to 69% as compared with wt ITK (107 min). The pleckstrin homology domain of wt ITK binds most prominently to phosphatidylinositol monophosphates (PI(3)P, PI(4)P, PI(5)P) and to lesser extend to its double or triple phosphorylated derivates (PIP2, PIP3), interactions which were dramatically reduced in the patient with the ITK(R29H) mutant. ITK mutations are distributed over the entire protein and include missense, nonsense and indel mutations, reminiscent of the situation in its sister kinase in B cells, Bruton's tyrosine kinase.

  18. Prognostic utility of preimplantation kidney biopsy from deceased older donors in first year post-transplant renal function.

    Science.gov (United States)

    Amenábar, Juan J; Camacho, Jhon A; Gómez-Larrambe, Nerea; Visus, Teresa; Pijoan, José I; González del Tánago, Jaime; Zárraga, Sofía; García-Olaverri, Jorge; Gaínza, Francisco J

    2016-01-01

    Preimplantation renal biopsy provides potentially valuable information about post-transplant renal function. To assess the prognostic value of preimplantation kidney biopsy from older donors in determining 1-year post-transplant estimated glomerular filtration rate MDRD-4 (eGFR). We evaluated a cohort of 124 renal transplant recipients from deceased donors ≥60 years old, performed at our center between March 2008 and May 2012. Biopsies were assessed by applying the score proposed by O'Valle et al. The overall score was stratified into 3 levels: 0-3, 4-5 and 6-8 points. Kidneys scoring > 8 points were discarded. A total of 77% of the donors were ≥70 years. One year post-transplant, mean eGFR (SD) was lower in transplant recipients with 6-8 points (38.5 [14.1] mL/min/1.73m(2)) than in the group scoring 4-5 points (46.3 [15.7] [p=0.03]) and the group scoring 0-3 (49.6 [12.5] [P=.04]). Seven patients (19%) had eGFR renal biopsy were associated with a worse 1-year post-transplant eGFR. Delayed graft function and acute rejection were significant risk factors for 1-year post-transplant low eGFR. Copyright © 2015 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.

  19. Post-Transplant Diabetes Mellitus: Causes, Treatment, and Impact on Outcomes.

    Science.gov (United States)

    Shivaswamy, Vijay; Boerner, Brian; Larsen, Jennifer

    2016-02-01

    Post-transplant diabetes mellitus (PTDM) is a frequent consequence of solid organ transplantation. PTDM has been associated with greater mortality and increased infections in different transplant groups using different diagnostic criteria. An international consensus panel recommended a consistent set of guidelines in 2003 based on American Diabetes Association glucose criteria but did not exclude the immediate post-transplant hospitalization when many patients receive large doses of corticosteroids. Greater glucose monitoring during all hospitalizations has revealed significant glucose intolerance in the majority of recipients immediately after transplant. As a result, the international consensus panel reviewed its earlier guidelines and recommended delaying screening and diagnosis of PTDM until the recipient is on stable doses of immunosuppression after discharge from initial transplant hospitalization. The group cautioned that whereas hemoglobin A1C has been adopted as a diagnostic criterion by many, it is not reliable as the sole diabetes screening method during the first year after transplant. Risk factors for PTDM include many of the immunosuppressant medications themselves as well as those for type 2 diabetes. The provider managing diabetes and associated dyslipidemia and hypertension after transplant must be careful of the greater risk for drug-drug interactions and infections with immunosuppressant medications. Treatment goals and therapies must consider the greater risk for fluctuating and reduced kidney function, which can cause hypoglycemia. Research is actively focused on strategies to prevent PTDM, but until strategies are found, it is imperative that immunosuppression regimens are chosen based on their evidence to prolong graft survival, not to avoid PTDM.

  20. Post-transplant lymphoproliferative disease after allogeneic hematopoietic stem cell transplantation: a single-center experience.

    Science.gov (United States)

    Luo, Lan; Zhang, Lin; Cai, Bo; Li, Honghua; Huang, Wenrong; Jing, Yu; Zhu, Haiyan; Zhao, Yu; Bo, Jian; Wang, Quanshun; Han, Xiaoping; Yu, Li; Gao, Chunji

    2014-01-08

    Post-transplant lymphoproliferative disease (PTLD) is a rare and serious complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT) or solid organ transplantation. We conducted a retrospective analysis of the occurrence of post-transplant lymphoproliferative disease in allo-HSCT recipients over 12 years in a single center in China. A total of 343 patients received allo-HSCT. The conditioning therapy consisted of a busulfan/cyclophosphamide-based regimen, a fludarabine/cyclophosphamide-based regimen, or total-body irradiation and cyclophosphamide. In transplantations from unrelated donors and haplo-identical donors, patients also received antithymocyte globulin (ATG) or thymoglobulin as part of the conditioning. Five of the 343 patients (1.46%) were diagnosed with PTLD and all 5 were given ATG as part of conditioning. Among these 5 patients, 4 had lymphoid neoplasm before transplantation. EBV-positivity was confirmed in 4 patients. All 5 PTLD patients received reduction of immunosuppression (RI) as fundamental therapy. At follow-up on April 1, 2013, 1 patient had survived for 2 years and 1 had survived for 9 years. The correlation of PTLD with ATG and underlying diseases were examined by statistical analysis using the chi-squared test or Fisher's exact test (P=0.011 and 0.025, respectively). Although only 1.46% of patients progressed to PTLD associated with ATG and underlying diseases, the mortality was still high. Moreover, RI can be an effective therapy for PTLD patients, but other approaches should be further explored.

  1. Spontaneous remission of post-transplant recurrent focal and segmental glomerulosclerosis

    Directory of Open Access Journals (Sweden)

    Bassam Saeed

    2011-01-01

    Full Text Available A 12-year-old girl with a history of steroid and cyclosporine (CsA resistant nephrotic syndrome owing to focal and segmental glomerulosclerosis (FSGS has progressed to end-stage renal disease (ESRD for which she underwent hemodialysis for 18 months before she successfully received a fully matched kidney transplant from her sister at the age of nine years. The post transplantation (Tx period was marked by an early and massive proteinuria indicating recurrent FSGS for which she received 12 sessions of plasmapheresis (PP; unfortunately, she did not appear to have any response to the PP therapy; thereafter, a conservative management comprising essentially enalapril and losartan has been initiated and was also not successful during the first four months, however, a very gradual response has been noticed to occur after five months of conservative therapy and ultimately, the patient attained complete remission after 21 months of treatment. Amazingly, 15 months after discontinuation of enalapril and losartan, she remained in a complete and sustained remission with a good renal allograft function. To the best of our knowledge, this is the first case ever reported in the literature of a "spontaneous" remission of post transplant recurrent FSGS.

  2. Negative outcomes after liver transplantation in patients with alcoholic liver disease beyond the fifth post-transplant year.

    Science.gov (United States)

    Grąt, Michał; Lewandowski, Zbigniew; Grąt, Karolina; Wronka, Karolina Maria; Krasnodębski, Maciej; Barski, Krzysztof; Zborowska, Hanna; Patkowski, Waldemar; Zieniewicz, Krzysztof; Krawczyk, Marek

    2014-10-01

    Although up to 50% of patients with alcoholic liver disease (ALD) resume alcohol consumption after liver transplantation (LT), numerous studies indicate that long-term results are not compromised. This study focused on evaluating the impact of ALD on outcomes up to and beyond the fifth year after LT. Among the 432 primary LT recipients included in this study, 97 underwent transplantation for ALD. Alcohol relapse rate at 10 yr was 33.5%, with younger recipient age being the only independent predictor (p = 0.019). Survival of patients with ALD (77.0%) was similar to those without (79.0%) up to the fifth post-transplant year (p = 0.655) but worse during the five subsequent years among the five-yr survivors (70.6% vs. 92.9%; p = 0.002). ALD was an independent risk factor for poorer survival beyond the fifth post-transplant year (p = 0.049), but not earlier (p = 0.717). Conversely, alcohol relapse increased the risk of death only during the first five post-transplant years (p = 0.039). There were no significant differences regarding graft failure incidence between ALD and non-ALD recipients up to the fifth post-transplant year (7.3% vs. 11.6%; p = 0.255) and beyond (12.9% vs. 5.0%; p = 0.126). In conclusion, pre-transplant diagnosis of ALD yields negative effects on post-transplant outcomes beyond the fifth post-transplant year, not attributable to recidivism.

  3. Post-transplant cyclophosphamide versus anti-thymocyte globulin as graft- versus-host disease prophylaxis in haploidentical transplant

    Science.gov (United States)

    Ruggeri, Annalisa; Sun, Yuqian; Labopin, Myriam; Bacigalupo, Andrea; Lorentino, Francesca; Arcese, William; Santarone, Stella; Gülbas, Zafer; Blaise, Didier; Messina, Giuseppe; Ghavamzadeh, Ardeshi; Malard, Florent; Bruno, Benedetto; Diez-Martin, Jose Luis; Koc, Yener; Ciceri, Fabio; Mohty, Mohamad; Nagler, Arnon

    2017-01-01

    Severe graft-versus-host disease is a major barrier for non-T-cell-depleted haploidentical stem cell transplantation. There is no consensus on the optimal graft-versus-host disease prophylaxis. This study compared the two most commonly used graft-versus-host disease prophylaxis regimens (post-transplant cyclophosphamide-based vs. the anti-thymocyte globulin-based) in adults with acute myeloid leukemia reported to the European Society for Blood and Bone Marrow Transplantation. A total of 308 patients were analyzed; 193 received post-transplant cyclophosphamide-based regimen and 115 anti-thymocyte globulin-based regimen as anti-graft-versus-host disease prophylaxis. The post-transplant cyclophosphamide-based regimen was more likely to be associated to bone marrow as graft source (60% vs. 40%; P=0.01). Patients in the post-transplant cyclophosphamide-based regimen group had significantly less grade 3–4 acute graft-versus-host disease than those in the anti-thymocyte globulin-based group (5% vs. 12%, respectively; P=0.01), comparable to chronic graft-versus-host disease. Multivariate analysis showed that non-relapse mortality was lower in the post-transplant cyclophosphamide-based regimen group [22% vs. 30%, Hazard ratio (HR) 1.77(95%CI: 1.09–2.86); P=0.02] with no difference in relapse incidence. Patients receiving post-transplant cyclophosphamide-based regimen had better graft-versus-host disease-free, relapse-free survival [HR 1.45 (95%CI: 1.04–2.02); P=0.03] and leukemia-free survival [HR 1.48 (95%CI: 1.03–2.12); P=0.03] than those in the anti-thymocyte globulin-based group. In the multivariate analysis, there was also a trend for a higher overall survival [HR 1.43 (95%CI: 0.98–2.09); P=0.06] for post-transplant cyclophosphamide-based regimen versus the anti-thymocyte globulin-based group. Notably, center experience was also associated with non-relapse mortality and graft-versus-host disease-free, relapse-free survival. Haplo-SCT using a post-transplant

  4. Intravascular large B cell lymphoma

    Directory of Open Access Journals (Sweden)

    Ricardo García-Muñoz

    2014-01-01

    Full Text Available Intravascular large B cell lymphoma (IVBCL is a rare type of extranodal large B cell lymphoma characterized by selective growth of lymphoma cells within the microvasculature. We present an illustrative case of intravascular B cell lymphoma suspected by the presence of a very small monoclonal B cell population identified by immunophenotype and polymerase chain reaction in bone marrow. The diagnosis was confirmed by skin biopsy.

  5. Alternative Donor Transplantation with High-Dose Post-Transplantation Cyclophosphamide for Refractory Severe Aplastic Anemia

    Science.gov (United States)

    DeZern, Amy E.; Zahurak, Marianna; Symons, Heather; Cooke, Kenneth; Jones, Richard J.; Brodsky, Robert A.

    2017-01-01

    Severe aplastic anemia (SAA) is a life-threatening hematopoietic stem cell disorder that is treated with bone marrow transplantation (BMT) or immunosuppressive therapy (IST). The management of patients with refractory SAA after IST is a major challenge. Alternative donor BMT is the best chance for cure in refractory SAA, but morbidity and mortality from graft failure and complications of graft-versus-host disease (GVHD) have limited enthusiasm for this approach. Here, we employed post-transplantation high-dose cyclophosphamide in an effort to safely expand the donor pool in 16 consecutive patients with refractory SAA who did not have a matched sibling donor. Between July 2011 and August 2016, 16 patients underwent allogeneic (allo) BMT for refractory SAA from 13 haploidentical donors and 3 unrelated donors. The nonmyeloablative conditioning regimen consisted of antithymocyte globulin, fludarabine, low-dose cyclophosphamide, and total body irradiation. Post-transplantation cyclophosphamide 50 mg/kg/day i.v. on days +3 and +4 was administered for GVHD prophylaxis. Additionally, patients received mycophenolate mofetil on days +5 through 35 and tacrolimus from day +5 through 1 year. The median age of the patients at the time of transplantation was 30 (range, 11 to 69) years. The median time to neutrophil recovery over 1000 × 103/mm3 for 3 consecutive days was 19 (range, 16 to 27) days, to red cell engraftment was 25 (range, 2 to 58) days, and to last platelet transfusion to keep platelets counts over 50 × 103/mm3 was 27.5 (range, 22 to 108) days. Graft failure, primary or secondary, was not seen in any of the patients. All 16 patients are alive, transfusion independent, and without evidence of clonality. The median follow-up is 21 (range, 3 to 64) months. Two patients had grade 1 or 2 skin-only acute GVHD. These same 2 also had mild chronic GVHD of the skin/mouth requiring systemic steroids. One of these GVHD patients was able to come off all IST by 15 months and the

  6. First-line use of rituximab correlates with increased overall survival in late post-transplant lymphoproliferative disorders: retrospective, single-centre study.

    Science.gov (United States)

    Martínez-Calle, Nicolás; Alfonso, Ana; Rifón, José; Herrero, Ignacio; Errasti, Pedro; Rábago, Gregorio; Merino, Juana; Panizo, Ángel; Pardo, Javier; Prósper, Felipe; García-Muñoz, Ricardo; Lecumberri, Ramón; Panizo, Carlos

    2017-01-01

    This retrospective study evaluates the impact of rituximab on PTLD response and survival in a single-centre cohort. PTLD cases between 1984 and 2009, including heart, kidney, liver and lung transplant recipients, were included. Survival was analysed taking into account the type of PTLD (monomorphic vs. polymorphic), EBV infection status, IPI score, Ann Arbor stage and use of rituximab. Among 1335 transplanted patients, 24 developed PTLD. Median age was 54 yr (range 29-69), median time to diagnosis 50 months (range 0-100). PTLD type was predominantly late/monomorphic (79% and 75%), mostly diffuse large B-cell type. Overall response rate (ORR) was 62% (66% rituximab vs. 50% non-rituximab; P = 0.5). R-CHOP-like regimens were used most frequently (72% of patients treated with rituximab). Median overall survival was 64 months (CI 95% 31-96). OS was significantly increased in patients treated with rituximab (P = 0.01; CI 95% rituximab 58-79 months; non-rituximab 1-30 months). Post-transplant immunosuppression regimen had no effect on survival or time to PTLD, except for cyclosporine A (CyA), which associated with increased time to PTLD (P = 0.02). Rituximab was associated with increased survival in our single-centre series, and it should be considered as first-line therapy for PTLD patients. The possible protective effect of CyA for development of PTLD should be prospectively evaluated.

  7. Early Gastric Post-Transplant Lymphoproliferative Disorder and H pylori Detection after Kidney Transplantation: A Case Report and Review of the Literature

    Directory of Open Access Journals (Sweden)

    CL Nash

    2000-01-01

    Full Text Available The incidence of post-transplantation lymphoproliferative disorder (PTLD in the adult renal transplant population ranges from 0.7% to 4%. The majority of cases involve a single site and arise, on average, seven months after transplantation. Histopathology usually reveals B-cell proliferative disease and has been standardized into its own classification. Treatment modalities consist of decreased immunosuppression, eradication of Epstein-Barr virus, surgical resection, systemic chemotherapy and monoclonal antibody therapy; however, mortality remains high, typically with a short survival time. In patients who have undergone renal transplantation, approximately 10% of those with PTLDs present with gastrointestinal symptomatology and disease. Reported sites include the stomach, and small and large bowel. Very few cases of Helicobacter pylori or mucosal-associated lymphoid tissue have been described in association with PTLD. In the era of cyclosporine immunosuppression, the incidence of PTLD affecting the gastrointestinal tract may be increasing in comparison with the incidence seen with the use of older immunosuppression regimens. A case of antral PTLD and H pylori infection occurring three months after renal transplantation is presented, and the natural history and management of gastric PTLD are reviewed.

  8. Post-Transplant Lymphoproliferative Disorder (PTLD) Manifesting in the Oral Cavity of a 13-Year-Old Liver Transplant Recipient (LTx).

    Science.gov (United States)

    Krasuska-Sławińska, Ewa; Minko-Chojnowska, Izabela; Pawłowska, Joanna; Dembowska-Bagińska, Bożenna; Pronicki, Maciej; Olczak-Kowalczyk, Dorota

    2015-08-18

    BACKGROUND Post-transplant lymphoproliferative disorder (PTLD) is a potential complication of solid organ or bone marrow transplants. The main PTLD risk factors are: the Epstein-Barr virus (EBV), transplant type, and use of immunosuppressants. It mainly consists of an uncontrolled growth of lymphocytes in transplant recipients under chronic immunosuppressive therapy. About 85% of PTLDs are EBV-containing B-cell proliferations; 14% are T-cell proliferations, of which only 40% contain EBV; and the remaining 1% is NK-cell or plasmocyte proliferations. PTLD may present various clinical manifestations, from non-specific mononucleosis-like syndrome to graft or other organ damage resulting from pathologic lymphocyte infiltration. PTLD may manifest in the oral cavity. CASE REPORT The objective of this study was to present the case of a 13-year-old female living-donor liver transplant recipient, resulting from biliary cirrhosis caused by congenital biliary atresia, with exophytic fibrous lesions on buccal mucosa and tongue. Exophytic and hyperplastic lesion of oral mucosa were removed and histopathological examination revealed polymorphic PTLD. The patient underwent 6 cycles of CHOP chemotherapy and all the oral lesions regressed completely. CONCLUSIONS All oral pathological lesions in organ transplant recipients need to be surgically removed and histopathologically examined because they present an increased risk of neoplastic transformations such as PTLD.

  9. Early Non-Immunological Post Transplant complications: A Single Center Experience

    Directory of Open Access Journals (Sweden)

    Jabur Wael

    2008-01-01

    Full Text Available To assess non-immunological complications affecting renal transplant patients in the first six months after transplantation in Al-Karama hospital, Baghdad, Iraq, we studied 68 patients (49 males, 19 females attending the clinic during the year 2006. Forty six (67% patients received kidneys from related and 22 (33% from unrelated donors. The patients revealed the following complications: post transplant hypertension in 28 (41% patient, infection (mostly bacterial in 27 (37%, new onset diabetes in 11 (16%, calcineurin inhibitor toxicity in 10 (14%, anemia in 8 (12%, surgical complications in 7 (10%, slow graft recovery in 4 (6%, cardiovascular complications in 3 (4%, and Kaposi sarcoma in 2 (2.9%.Transient hyperglycemia, hypertension, infection and diabetes mel-litus were the commonest early complications of renal transplantation. The incidence of complications is comparable to the average reported in the literature, especially in this region of the world.

  10. [Monomorphic post-transplant T-lymphoproliferative disorder after autologous stem cell transplantation for multiple myeloma].

    Science.gov (United States)

    Ishikawa, Tetsuya; Shimizu, Hiroaki; Takei, Toshifumi; Koya, Hiroko; Iriuchishima, Hirono; Hosiho, Takumi; Hirato, Junko; Kojima, Masaru; Handa, Hiroshi; Nojima, Yoshihisa; Murakami, Hirokazu

    2016-01-01

    We report a rare case of T cell type monomorphic post-transplant lymphoproliferative disorders (PTLD) after autologous stem cell transplantation. A 53-year-old man with multiple myeloma received autologous stem cell transplantation and achieved a very good partial response. Nine months later, he developed a high fever and consciousness disturbance, and had multiple swollen lymph nodes and a high titer of Epstein-Barr (EB) virus DNA in his peripheral blood. Neither CT nor MRI of the brain revealed any abnormalities. Cerebrospinal fluid contained no malignant cells, but the EB virus DNA titer was high. Lymph node biopsy revealed T cell type monomorphic PTLD. Soon after high-dose treatment with methotrexate and cytosine arabinoside, the high fever and consciousness disturbance subsided, and the lymph node swelling and EB virus DNA disappeared. Given the efficacy of chemotherapy in this case, we concluded that the consciousness disturbance had been induced by central nervous system involvement of monomorphic PTLD.

  11. Quaternary epitopes of α345(IV) collagen initiate Alport post-transplant anti-GBM nephritis

    DEFF Research Database (Denmark)

    Olaru, Florina; Luo, Wentian; Wang, Xu-Ping

    2013-01-01

    Alport post-transplant nephritis (APTN) is an aggressive form of anti-glomerular basement membrane disease that targets the allograft in transplanted patients with X-linked Alport syndrome. Alloantibodies develop against the NC1 domain of α5(IV) collagen, which occurs in normal kidneys, including...... of alloantibodies against allogeneic collagen IV. Some alloantibodies targeted alloepitopes within α5NC1 monomers, shared by α345NC1 and α1256NC1 hexamers. Other alloantibodies specifically targeted alloepitopes that depended on the quaternary structure of α345NC1 hexamers. In Col4a5-null mice, immunization...... with native forms of allogeneic collagen IV exclusively elicited antibodies to quaternary α345NC1 alloepitopes, whereas alloimmunogens lacking native quaternary structure elicited antibodies to shared α5NC1 alloepitopes. These results imply that quaternary epitopes within α345NC1 hexamers may initiate...

  12. Sequence analysis of EBV immune evasion gene BNLF2a in EBV associated tumors and healthy individuals from nasopharyngeal carcinoma endemic and non-endemic regions of China.

    Science.gov (United States)

    Liu, Song; Wang, Xiaofeng; Shu, Jun; Zhao, Zhenzhen; Sun, Zhifu; Luo, Bing

    2015-11-01

    BNLF2a is an Epstein-Barr virus (EBV) immune evasion gene. Its protein is located in the endoplasmic reticulum (ER) membrane, and can inhibit the antigen transporting function of TAP, thereby perturbing the immune response to EBV in lytic and prelatent phase. In order to explore whether the polymorphism of BNLF2a gene has a role in different types of EBV associated tumors, we conducted complete sequencing of the gene BNLF2a in 408 cases of EBV positive tumors (76 lymphomas, 45 gastric carcinomas, and 85 nasopharyngeal carcinomas in northern China and 27 lymphomas, 30 gastric carcinomas, and 57 nasopharyngeal carcinomas in southern China) and throat washings from healthy individuals (39 in northern China and 49 in southern China). Two main variant types of BNLF2a were identified. Type BNLF2a-A, which was similar to B95-8, was dominant in all sub-populations (66.7-100%) in this study. Type BNLF2a-B was characterized by the mutations at position 8 and 40. The variation patterns of BNLF2a were significantly different between samples from northern and southern China (P China (P China (33.3%), and the proportion of this type was higher in the northern than in the southern NPCs. These data demonstrate that the BNLF2a gene is highly conserved, and its polymorphism is geographically restricted. Type BNLF2a-B is more prevalent in northern China and may be less tumor transformative.

  13. Comparison between doppler ultrasonography and renal scintigraphy in assessment of post-transplant renal function

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Yeo Chang; Shin, Byung Seok; Ohm, Joon Young; Kim, Seong Min; Ahn, Moon Sang; Yang, Shin Seok [Chungnam National University Hospital, Daejeon (Korea, Republic of); Park, Mi Hyun [Dept. of Radiology, Dankook University Hospital, Cheonan (Korea, Republic of)

    2016-05-15

    To compare the usefulness of Doppler ultrasonography and renal scintigraphy in the assessment of short- and long-term function of transplanted kidneys. We retrospectively reviewed the cases of 79 patients who underwent Doppler ultrasonography and technetium-99m diethylene triamine pentaacetic acid renal scintigraphy on the same day, within 4 days of renal transplantation. Image parameters were evaluated for statistical differences. There was a strong positive correlation between the glomerular filtration rate (GFR) as measured by renal scintigraphy and the estimated GFR (eGFR) based on serum creatinine levels (correlation coefficient = 0.71). Scan grade according to the time-activity curve, resistive index, and end diastolic velocity showed moderate correlations with the eGFR (correlation coefficients = -0.557, -0.329, and 0.370, respectively) in the early post-transplantation period. The mean survival time was longer in patients with lower resistive indices (≤ 0.68, 54.9 months vs. > 0.68, 29.5 months) and lower pulsatility indices (≤ 1.32, 53.8 months vs. > 1.32, 28.7 months); however, there were no statistically significant differences in the long-term follow-up period (p = 0.121 for resistive index and p = 0.074 for pulsatility index). Renal scintigraphy is a more sensitive method than Doppler ultrasonography for assessing transplanted kidney function in the early post-transplantation period. Doppler ultrasonography might reflect the long-term survival time. However, it is difficult to predict long-term renal function using either method.

  14. Augmenting the post-transplantation growth and survivorship of juvenile scleractinian corals via nutritional enhancement.

    Directory of Open Access Journals (Sweden)

    Tai Chong Toh

    Full Text Available Size-dependent mortality influences the recolonization success of juvenile corals transplanted for reef restoration and assisting juvenile corals attain a refuge size would thus improve post-transplantation survivorship. To explore colony size augmentation strategies, recruits of the scleractinian coral Pocillopora damicornis were fed with live Artemia salina nauplii twice a week for 24 weeks in an ex situ coral nursery. Fed recruits grew significantly faster than unfed ones, with corals in the 3600, 1800, 600 and 0 (control nauplii/L groups exhibiting volumetric growth rates of 10.65 ± 1.46, 4.69 ± 0.9, 3.64 ± 0.55 and 1.18 ± 0.37 mm3/week, respectively. Corals supplied with the highest density of nauplii increased their ecological volume by more than 74 times their initial size, achieving a mean final volume of 248.38 ± 33.44 mm3. The benefits of feeding were apparent even after transplantation to the reef. The corals in the 3600, 1800, 600 and 0 nauplii/L groups grew to final sizes of 4875 ± 260 mm3, 2036 ± 627 mm3, 1066 ± 70 mm3 and 512 ± 116 mm3, respectively. The fed corals had significantly higher survival rates than the unfed ones after transplantation (63%, 59%, 56% and 38% for the 3600, 1800, 600 and 0 nauplii/L treatments respectively. Additionally, cost-effectiveness analysis revealed that the costs per unit volumetric growth were drastically reduced with increasing feed densities. Corals fed with the highest density of nauplii were the most cost-effective (US$0.02/mm3, and were more than 12 times cheaper than the controls. This study demonstrated that nutrition enhancement can augment coral growth and post-transplantation survival, and is a biologically and economically viable option that can be used to supplement existing coral mariculture procedures and enhance reef restoration outcomes.

  15. Post-transplant lymphoproliferative disorder in the pelvis successfully treated with consolidative radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Habibeh, Omar; Elsayad, Khaled; Kriz, Jan; Haverkamp, Uwe; Eich, Hans Theodor [University Hospital of Muenster, Department of Radiation Oncology, Muenster (Germany)

    2017-01-15

    Post-transplant lymphoproliferative disorders (PTLDs) are aggressive malignancies which represent one of the major post-transplant complications. However, treatment options vary significantly and localized disease may be curatively treated with radiotherapy (RT) or surgery. We report a case of recurrent rectal PTLD, which was successfully treated by chemoimmunotherapy followed by RT. We describe a patient who developed a rectal lymphoproliferative lesion 11 years after kidney transplant, which was successfully treated with consolidative RT using 25.4 Gy sequential to chemoimmunotherapy (R-CHOP). RT was well tolerated and the patient showed no signs of grade 3 or 4 toxicity. This patient is free of recurrence 52 months after RT, with an overall survival of 62 months since diagnosis. Conventionally fractionated moderate-dose RT appears to be a tolerable and effective treatment option for localized PTLD if a sufficient systemic treatment cannot be applied. (orig.) [German] Posttransplantationslymphoproliferative Erkrankungen (PTLDs) sind eine haeufige Komplikation nach einer Organtransplantation. Nichtdestotrotz unterscheiden sich die Behandlungsmoeglichkeiten signifikant und vor allem lokalisierte Stadien koennen kurativ entweder mit Strahlentherapie (RT) und/oder Operation behandelt werden. Wir berichten ueber einen Fall einer rezidivierten rektalen PTLD, die erfolgreich mit einer Chemoimmuntherapie mit anschliessender RT behandelt wurde. Wir beschreiben einen Patienten der 11 Jahre nach einer Nierentransplantation eine PTLD entwickelte. Diese wurde erfolgreich mit konsolidierender RT (25,4 Gy) im Anschluss an eine Chemoimmuntherapie (R-CHOP) behandelt. Die RT wurde komplikationslos vertragen und es zeigten sich keine Nebenwirkungen. Das rezidivfreie Ueberleben betrug zum Zeitpunkt der letzten Nachsorgeuntersuchung 52 Monate mit einer Gesamtueberlebenszeit von 62 Monaten seit der Diagnose. Die konventionelle fraktionierte moderat dosierte RT scheint eine gut

  16. Late Recurrent Post-Transplant Primary Biliary Cirrhosis in British Columbia

    Directory of Open Access Journals (Sweden)

    Eric M Yoshida

    1997-01-01

    Full Text Available Late recurrent primary biliary cirrhosis (PBC following orthotopic liver transplant remains a controversial topic. The first documented case of recurrence occurring in 16 patients transplanted for PBC and followed at the authors' institution for longer than one year is presented. A 54-year-old man transplanted for PBC developed a cholestatic pattern of enzyme elevation on post-transplant day (PTD 1305. Repeat antimitochondrial antibody was strongly positive (1:300 to 1:400. A liver biopsy revealed severe bile duct damage, lymphocytic cholangitis, focal periductal noncaseating granuloma and minimal endotheliitis. Recurrent PBC was diagnosed. At the time of orthotopic liver transplant this patient received induction immunosuppression with OKT3 crossed over to cyclosporine (CsA, azathioprine (AZA and prednisone. AZA was discontinued early and maintenance CsA tapered to a target trough level of 150 to 200 ng/mL by PTD 365. Prednisone was withdrawn by PTD 664. CsA levels during PTDs 1225 to 1305 (before elevation of hepatobiliary enzymes were below target at 114 to 166 ng/mL. Of the 16 patients, all but three were maintained on CsA, AZA and prednisone. One was on CsA (trough levels on target and AZA; the other two, including the patient with recurrent PBC, were on CsA only. The trough CsA level of the patient without recurrent PBC has been within the target range. The authors speculate that the underlying defect in immunoregulation in PBC persists post-transplant and that in the patient without recurrent PBC this defect was unmasked by lowered maintenance immunosuppression - allowing recurrence of PBC in a previously stable liver allograft.

  17. A single center experience: post-transplantation adjuvant chemotherapy impacts the prognosis of hepatocellular carcinoma patients

    Institute of Scientific and Technical Information of China (English)

    Wu Junyi; Sun Hongcheng; Han Zhongbo; Peng Zhihai

    2014-01-01

    Background The aim of this research was to investigate the impact of post-transplantation adjuvant chemotherapy in the prevention of tumor recurrence and metastasis for hepatocellular carcinoma (HCC) exceeding Milan criteria after liver transplantation.Methods A total of 117 patients with HCC exceeding the Milan criteria who had undergone orthotopic liver transplantation (OLT) from August 2002 to February 2009 were enrolled and retrospectively analyzed.The patients were divided into four groups according to chemotherapy regimens and the impact of different chemotherapy regimens on survival,disease-free survival,and adverse effects were compared.Results One year survival rates for the gemicitabine,conventional chemotherapy,oxaliplatin plus capecitabine and the best supportive care (BSC) group were 87.5%,84.2%,81.6%,and 67.5%.The 3-year survival rates were 48.1%,25.9%,31.6%,and 33.7%,respectively for the four groups.One year disease free survival rates for the four groups were 69.8%,47.4%,53.8%,and 45.7% respectively.And 3-year disease free survival rates were 43.2%,23.7%,23.6%,and 25.1% for the four groups.Stratification analysis showed that the gemcitabine regimen and conventional chemotherapy could significantly improve the survival rate and disease free survival rate for HCC patients who had major vascular invasion and/or microvascular invasion after liver transplantation compared with BSC group.Conclusions For HCC patients beyond Milan criteria,especially who had vascular invasion and/or micorvascular invasion,post-transplantation adjuvant chemotherapy can significantly improve survival.Gemcitabine is a proper regimen for postoperative adjuvant chemotherapy.Conventional chemotherapy can also benefit patients,but the adverse effects are not satisfactory.

  18. OVEREXPRESSION OF VASCULAR ENDOTHELIAL GROWTH FACTOR AND THE DEVELOPMENT OF POST-TRANSPLANTATION CANCER

    Science.gov (United States)

    Basu, Aninda; Contreras, Alan G.; Datta, Dipak; Flynn, Evelyn; Zeng, Liling; Cohen, Herbert T.; Briscoe, David M.; Pal, Soumitro

    2009-01-01

    Cancer is an increasing and major problem following solid organ transplantation. In part, the increased cancer risk is associated with the use of immunosuppressive agents, especially calcineurin inhibitors. We propose that the effect of calcineurin inhibitors on the expression of vascular endothelial growth factor (VEGF) leads to an angiogenic milieu that favors tumor growth. Here, we used 786-0 human renal cancer cells to investigate the effect of Cyclosporine (CsA) on VEGF expression. Utilizing a full-length VEGF promoter-luciferase construct, we found that CsA markedly induced VEGF transcriptional activation through the PKC signaling pathway, specifically involving PKCζ and PKCδ isoforms. Moreover, CsA promoted the association of PKCζ and PKCδ with the transcription factor Sp1 as observed by immunoprecipitation assays. Using promoter deletion constructs, we found that CsA-mediated VEGF transcription was primarily Sp1-dependent. Furthermore, CsA-induced and PKC-Sp1-mediated VEGF transcriptional activation was partially inhibited by pVHL. CsA also promoted the progression of human renal tumors in vivo, where VEGF is overexpressed. Finally, to evaluate the in vivo significance of CsA-induced VEGF overexpression in terms of post-transplantation tumor development, we injected CT26 murine carcinoma cells (known to form angiogenic tumors) into mice with fully MHC mismatched cardiac transplants. We observed that therapeutic doses of CsA increased tumor size, VEGF mRNA expression, and also enhanced tumor angiogenesis. However, co-administration of a blocking anti-VEGF antibody inhibited this CsA-mediated tumor growth. Collectively, these findings define PKC-mediated VEGF transcriptional activation as a key component in the progression of CsA-induced post-transplantation cancer. PMID:18632621

  19. Follow-up of post-transplant minimal residual disease and chimerism in childhood lymphoblastic leukaemia: 90 d to react.

    Science.gov (United States)

    Pochon, Cécile; Oger, Emmanuel; Michel, Gérard; Dalle, Jean-Hugues; Salmon, Alexandra; Nelken, Brigitte; Bertrand, Yves; Cavé, Hélène; Cayuela, Jean-Michel; Grardel, Nathalie; Macintyre, Elizabeth; Margueritte, Geneviève; Méchinaud, Françoise; Rohrlich, Pierre; Paillard, Catherine; Demeocq, François; Schneider, Pascale; Plantaz, Dominique; Poirée, Marilyne; Eliaou, Jean-François; Semana, Gilbert; Drunat, Séverine; Jonveaux, Philippe; Bordigoni, Pierre; Gandemer, Virginie

    2015-04-01

    Relapse after transplantation is a major cause of treatment failure in paediatric acute lymphoblastic leukaemia (ALL). Here, we report the findings of a prospective national study designed to investigate the feasibility of immune intervention in children in first or subsequent remission following myeloablative conditioning. This study included 133 children who received a transplant for ALL between 2005 and 2008. Minimal Residual Disease (MRD) based on T cell receptor/immunoglobulin gene rearrangements was measured on days -30, 30, 90 and 150 post-transplantation. Ciclosporin treatment was rapidly discontinued and donor lymphocyte infusions (DLI) were programmed for patients with a pre- or post-transplant MRD status ≥10(-3) . Only nine patients received DLI. Pre- and post-transplant MRD status, and the duration of ciclosporin were independently associated with 5-year overall survival (OS), which was 62·07% for the whole cohort. OS was substantially higher in patients cleared of MRD than in those with persistent MRD (52·3% vs. 14·3%, respectively). Only pre-transplant MRD status (Hazard Ratio 2·57, P = 0·04) and duration of ciclosporin treatment (P < 0·001) were independently associated with relapse. The kinetics of chimerism were not useful for predicting relapse, whereas MRD monitoring up to 90 d post-transplantation was a valuable prognostic tool to guide therapeutic intervention. © 2014 John Wiley & Sons Ltd.

  20. Histological and clinical findings in patients with post-transplantation and classical encapsulating peritoneal sclerosis: A European multicenter study

    NARCIS (Netherlands)

    J. Latus (Joerg); S.M. Habib (Meelad); D. Kitterer (Daniel); M.R. Korte (Mario); C. Ulmer (Christoph); P. Fritz (Peter); S. Davies (Simon); M. Lambie (Mark); M.D. Alscher (M. Dominik); M.G.H. Betjes (Michiel); S. Segerer (Stephan); N. Braun (Niko)

    2014-01-01

    textabstractBackground: Encapsulating peritoneal sclerosis (EPS) commonly presents after peritoneal dialysis has been stopped, either post-transplantation (PT-EPS) or after switching to hemodialysis (classical EPS, cEPS). The aim of the present study was to investigate whether PT-EPS and cEPS differ

  1. Post-transplant monitoring of soluble CD30 level as predictor of graft outcome: a single center experience from China.

    Science.gov (United States)

    Wang, Dong; Wu, Weizhen; Yang, Shunliang; Wang, Qinghua; Tan, Jianming

    2012-12-01

    There are no reliable parameters for post-transplantation immunological monitoring, which might enable recipient-tailored immunosuppressive therapy. 250 renal graft recipients were enrolled and detected for sCD30 level pre-transplantation, and on days 5 and 14, and on months 1, 3, 6, 12, 24, 36, 48 and 60 post-transplantation. Analysis was performed on correlation between sCD30 level and acute rejection, lung infection, or graft loss respectively. sCD30 levels descended to a nadir with a mean of 10.2 ± 3.8 U/mL on day 30 post-transplantation, then rose gradually, and approached 21.8 ± 10.1 U/mL on month 3, 34.2 ± 16.5 U/mL on month 6, and 42.9 ± 29.5 U/mL on month 12, then presented a stable level. Recipients with AR had significantly higher sCD30 levels than those without AR on days 5 and 14 post-transplantation. Recipients with pneumonia had significantly lower sCD30 levels within 3 months post-transplantation than those without pneumonia. Significantly higher sCD30 levels were recorded in recipients who suffered graft loss than those with normal graft function on days 5 and 14, and on months 6, 12, and 24. High sCD30 level (≥ 48.3 U/mL) at month 12 post-transplantation has an obvious detrimental effect on renal graft survival (p=0.000, HR=9.075). Serum sCD30 level might reflect immune state of renal graft recipients. Post-transplantation sequential monitoring of sCD30 level is necessary, which might not only identify recipients at the risk of acute rejection and graft loss, but also chosen as an independent predictor of pneumonia in renal transplant recipients. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Epstein-barr virus latency in B cells leads to epigenetic repression and CpG methylation of the tumour suppressor gene Bim.

    Directory of Open Access Journals (Sweden)

    Kostas Paschos

    2009-06-01

    Full Text Available In human B cells infected with Epstein-Barr virus (EBV, latency-associated virus gene products inhibit expression of the pro-apoptotic Bcl-2-family member Bim and enhance cell survival. This involves the activities of the EBV nuclear proteins EBNA3A and EBNA3C and appears to be predominantly directed at regulating Bim mRNA synthesis, although post-transcriptional regulation of Bim has been reported. Here we show that protein and RNA stability make little or no contribution to the EBV-associated repression of Bim in latently infected B cells. However, treatment of cells with inhibitors of histone deacetylase (HDAC and DNA methyltransferase (DNMT enzymes indicated that epigenetic mechanisms are involved in the down-regulation of Bim. This was initially confirmed by chromatin immunoprecipitation analysis of histone acetylation levels on the Bim promoter. Consistent with this, methylation-specific PCR (MSP and bisulphite sequencing of regions within the large CpG island located at the 5' end of Bim revealed significant methylation of CpG dinucleotides in all EBV-positive, but not EBV-negative B cells examined. Genomic DNA samples exhibiting methylation of the Bim promoter included extracts from a series of explanted EBV-positive Burkitt's lymphoma (BL biopsies. Subsequent analyses of the histone modification H3K27-Me3 (trimethylation of histone H3 lysine 27 and CpG methylation at loci throughout the Bim promoter suggest that in EBV-positive B cells repression of Bim is initially associated with this repressive epigenetic histone mark gradually followed by DNA methylation at CpG dinucleotides. We conclude that latent EBV initiates a chain of events that leads to epigenetic repression of the tumour suppressor gene Bim in infected B cells and their progeny. This reprogramming of B cells could have important implications for our understanding of EBV persistence and the pathogenesis of EBV-associated disease, in particular BL.

  3. Whole blood EBV-DNA predicts outcome in diffuse large B-cell lymphoma.

    Science.gov (United States)

    Tisi, Maria Chiara; Cupelli, Elisa; Santangelo, Rosaria; Maiolo, Elena; Alma, Eleonora; Giachelia, Manuela; Martini, Maurizio; Bellesi, Silvia; D'Alò, Francesco; Voso, Maria Teresa; Pompili, Maurizio; Leone, Giuseppe; Larocca, Luigi Maria; Hohaus, Stefan

    2016-01-01

    An association between Epstein-Barr Virus (EBV) infection and lymphoproliferative diseases has been reported with EBV + diffuse large B cell-lymphoma (DLBCL) of the elderly described as a distinct entity. In a cohort of 218 human immunodeficiency virus (HIV)-negative patients with diffuse large B-cell lymphomas, we detected EBV-DNA in 25% of whole blood (WB) samples at diagnosis. Presence and viral load in WB, mononuclear cells or plasma did not predict the presence of EBV in the tumor biopsy. Positive Hepatitis C virus (HCV) serology was associated with a higher frequency of EBV in WB. Patients with EBV-DNA in WB had a significantly shorter progression-free (p = 0.02) and overall survival (p = 0.05) after immunochemotherapy with R-CHOP (Rituximab, Cyclophosphamide, Doxorubicin, Vincristine, Prednisolone). We conclude that detection of EBV in WB is not a surrogate marker for EBV-association in diffuse large B-cell lymphoma, however it associates with worse outcome.

  4. Is gastric lymphoepithelioma-like carcinoma a special subtype of EBV-associated gastric carcinoma? New insight based on clinicopathological features and EBV genome polymorphisms.

    Science.gov (United States)

    Cheng, Na; Hui, Da-yang; Liu, Yong; Zhang, Na-na; Jiang, Ye; Han, Jing; Li, Hai-Gang; Ding, Yun-Gang; Du, Hong; Chen, Jian-Ning; Shao, Chun-Kui

    2015-04-01

    Gastric lymphoepithelioma-like carcinoma (LELC) is a rare entity that is closely associated with Epstein-Barr virus (EBV). However, the EBV latency pattern and genome polymorphisms in gastric LELC have not been systematically explored. The clinicopathological features, EBV latency pattern and genome polymorphisms of EBV-positive gastric LELC in Guangzhou, southern China were investigated and compared with those of ordinary EBV-associated gastric carcinoma (EBVaGC) in the same area. Ten (1.42%) of 702 gastric carcinoma cases were identified as gastric LELC, in which eight (80%) cases were EBV-positive. The clinicopathological characteristics and EBV latency pattern of EBV-positive gastric LELC were similar to those of ordinary EBVaGC. In EBV genotype analysis, type A strain, type F, I, mut-W1/I, XhoI- and del-LMP1 variants were predominant among EBV-positive gastric LELCs, accounting for eight (100%), six (75%), eight (100%), seven (87.5%), five (62.5%) and six (75%) cases, respectively, which are similar to those in ordinary EBVaGC. For EBNA1 polymorphisms, the V-leu and P-ala subtypes were predominant in EBV-positive gastric LELC, which is different from the predominant V-val subtype in ordinary EBVaGC. EBV-positive gastric LELC has a favorable prognosis when compared to ordinary EBVaGC (median survival time 43.0 vs. 18.0 months). Gastric LELC is strongly associated with EBV and EBV-positive gastric LELC should be regarded as a special subtype of EBVaGC. This, to our best knowledge, is the first time in the world that the EBV latency pattern and genome polymorphisms of EBV-positive gastric LELC are systematically revealed.

  5. Self-Monitoring Kidney Function Post Transplantation: Reliability of Patient-Reported Data.

    Science.gov (United States)

    van Lint, Céline; Wang, Wenxin; van Dijk, Sandra; Brinkman, Willem-Paul; Rövekamp, Ton Jm; Neerincx, Mark A; Rabelink, Ton J; van der Boog, Paul Jm

    2017-09-26

    The high frequency of outpatient visits after kidney transplantation is burdensome to both the recovering patient and health care capacity. Self-monitoring kidney function offers a promising strategy to reduce the number of these outpatient visits. The objective of this study was to investigate whether it is safe to rely on patients' self-measurements of creatinine and blood pressure, using data from a self-management randomized controlled trial. For self-monitoring creatinine, each participant received a StatSensor Xpress-i Creatinine Meter and related test material. For self-monitoring blood pressure, each participant received a Microlife WatchBP Home, an oscillometric device for blood pressure self-measurement on the upper arm. Both devices had a memory function and the option to download stored values to a computer. During the first year post transplantation, 54 patients registered their self-measured creatinine values in a Web-based Self-Management Support System (SMSS) which provided automatic feedback on the registered values (eg, seek contact with hospital). Values registered in the SMSS were compared with those logged automatically in the creatinine device to study reliability of registered data. Adherence to measurement frequency was determined by comparing the number of requested with the number of performed measurements. To study adherence to provided feedback, SMSS-logged feedback and information from the electronic hospital files were analyzed. Level of adherence was highest during months 2-4 post transplantation with over 90% (42/47) of patients performing at least 75% of the requested measurements. Overall, 87.00% (3448/3963) of all registered creatinine values were entered correctly, although values were often registered several days later. If (the number of) measured and registered values deviated, the mean of registered creatinine values was significantly lower than what was measured, suggesting active selection of lower creatinine values

  6. PI3Kδ inhibition augments the efficacy of rapamycin in suppressing proliferation of Epstein-Barr virus (EBV)+ B cell lymphomas.

    Science.gov (United States)

    Furukawa, S; Wei, L; Krams, S M; Esquivel, C O; Martinez, O M

    2013-08-01

    Posttransplant lymphoproliferative disorder (PTLD) continues to be a devastating and potentially life-threatening complication in organ transplant recipients. PTLD is associated with EBV infection and can result in malignant B cell lymphomas. Here we demonstrate that the PI3K/Akt/mTOR pathway is highly activated in EBV+ B cell lymphoma lines derived from patients with PTLD. Treatment with the mTORC1 inhibitor Rapamycin (RAPA) partially inhibited the proliferation of EBV+ B cell lines. Resistance to RAPA treatment correlated with high levels of Akt phosphorylation. An mTORC1/2 inhibitor and a PI3K/mTOR dual inhibitor suppressed Akt phosphorylation and showed a greater anti-proliferative effect on EBV+ B lymphoma lines compared to RAPA. EBV+ B cell lymphoma lines expressed high levels of PI3Kδ. We demonstrate that PI3Kδ is responsible for Akt activation in EBV+ B cell lymphomas, and that selective inhibition of PI3Kδ by either siRNA, or a small molecule inhibitor, augmented the anti-proliferative effect of RAPA on EBV+ B cell lymphomas. These results suggest that PI3Kδ is a novel, potential therapeutic target for the treatment of EBV-associated PTLD and that combined blockade of PI3Kδ and mTOR provides increased efficacy in inhibiting proliferation of EBV+ B cell lymphomas.

  7. Sodium nitrite protects against kidney injury induced by brain death and improves post-transplant function.

    Science.gov (United States)

    Kelpke, Stacey S; Chen, Bo; Bradley, Kelley M; Teng, Xinjun; Chumley, Phillip; Brandon, Angela; Yancey, Brett; Moore, Brandon; Head, Hughston; Viera, Liliana; Thompson, John A; Crossman, David K; Bray, Molly S; Eckhoff, Devin E; Agarwal, Anupam; Patel, Rakesh P

    2012-08-01

    Renal injury induced by brain death is characterized by ischemia and inflammation, and limiting it is a therapeutic goal that could improve outcomes in kidney transplantation. Brain death resulted in decreased circulating nitrite levels and increased infiltrating inflammatory cell infiltration into the kidney. Since nitrite stimulates nitric oxide signaling in ischemic tissues, we tested whether nitrite therapy was beneficial in a rat model of brain death followed by kidney transplantation. Nitrite, administered over 2 h of brain death, blunted the increased inflammation without affecting brain death-induced alterations in hemodynamics. Kidneys were transplanted after 2 h of brain death and renal function followed over 7 days. Allografts collected from nitrite-treated brain-dead rats showed significant improvement in function over the first 2 to 4 days after transplantation compared with untreated brain-dead animals. Gene microarray analysis after 2 h of brain death without or with nitrite therapy showed that the latter significantly altered the expression of about 400 genes. Ingenuity Pathway Analysis indicated that multiple signaling pathways were affected by nitrite, including those related to hypoxia, transcription, and genes related to humoral immune responses. Thus, nitrite therapy attenuates brain death-induced renal injury by regulating responses to ischemia and inflammation, ultimately leading to better post-transplant kidney function.

  8. Clinical Application of Variation in Replication Kinetics During Episodes of Post-transplant Cytomegalovirus Infections

    DEFF Research Database (Denmark)

    Lodding, I P; Sengeløv, Henrik; da Cunha-Bang, C

    2015-01-01

    of the first CMV infection in the first year post-transplant could be calculated for 193 recipients of haematopoietic stem cell or solid organ transplantation. Factors determining the proportion of recipients with a high diagnostic CMV viral load (≥ 18,200 IU/mL) were explored using mathematical simulation......BACKGROUND: Cytomegalovirus (CMV) infection in transplant recipients is reported to replicate with a doubling time of 1.2-2 days, and weekly screening is recommended for early diagnosis. We re-evaluated these features in our cohort of transplant recipients. METHODS: The CMV doubling time....... FINDINGS: The overall median doubling time was 4.3 days (IQR 2.5-7.8) and was not influenced by prior CMV immunity, or type of transplantation (p > 0.4). Assuming a fixed doubling time of 1.3 days and screening intervals of 7 or 10 days, 11.1% and 33.3% were projected to have a high CMV viral load...

  9. Postprandial blood glucose level in maintenance hemodialysis patients predicts post-transplant-diabetes-mellitus.

    Science.gov (United States)

    Haider, D G; Mittermayer, F; Friedl, A; Batrice, A; Auinger, M; Wolzt, M; Hörl, W H

    2010-03-01

    Post-transplant-diabetes-mellitus (PTDM) is a frequent complication after kidney transplantation. One-hundred-and-seven patients with kidney transplantation were screened for the occurrence of PTDM. Of these, full data sets from 49 subjects were available with documented glucose concentrations during maintenance hemodialysis (MHD) and regular clinical follow-up of 7-34 months. For assessment of glucose metabolism the response to a standard meal during MHD was used in normoglycemic patients based on fasting blood glucose. Abnormal postprandial blood glucose concentration was defined as >140 mg/dl 2 h after food intake.Twelve end stage renal disease patients had abnormal postprandial blood glucose on MHD. All 12 subjects but also four MHD patients with normal postprandial and fasting blood glucose values developed PTDM. Multivariate Cox-regression analysis revealed that abnormal postprandial blood glucose is a strong predictor for PTDM (Hazard ratio: 42.3 (IQR: 7.9-227.2); p<0.001). Fasting blood glucose (94 vs. 100 mg/dl) was not different between MHD patients who did (n=16) or did not (n=33) develop PTDM.This study suggests that measurement of postprandial blood glucose during MHD identifies patients who develop PTDM after kidney transplantation. It should be used for screening of patients at risk.

  10. Pretreatment of Cisplatin in Recipients Attenuates Post-Transplantation Pancreatitis in Murine Model

    Directory of Open Access Journals (Sweden)

    Sheng Yan, Yuan Ding, Fei Sun, Zhongjie Lu, Liang Xue, Xiangyan Liu, Mingqi Shuai, Chen Fang, Yan Wang, Hui Cheng, Lin Zhou, Ming H Zheng, Shusen Zheng

    2012-01-01

    Full Text Available Pancreas transplantation is the definite treatment for type 1 diabetes that enables the achievement of long-term normoglycemia and insulin independence. However Post-Transplantation Pancreatitis (PTP due to ischemia reperfusion (IR injury and preservation is a major complication in pancreas transplantation. Owning the potential anti-inflammatory effect of Cisplatin (Cis in liver IR injury, we have examined if Cis could attenuate PTP using a murine model. We found that Cis is able to prevent inflammatory response in PTP. Pretreatment of Cis in recipient mice reduce the impairments of the grafts and hyperamylasimea in the recipients. We documented that the protective mechanism of Cis in PTP involves improvement of microcirculation, reduction of the mononuclear cellular infiltration and apoptosis, suppression of inflammatory cytokine-cascade and inhibition of translocation of high-motility group box protein-1 (HMGB-1 from nucleus to cytoplasm. In short, our study demonstrated that pretreatment of Cis in recipients may reduce the onset of PTP in pancreas transplantation.

  11. Catheter-associated urinary infection in kidney post-transplant patients

    Directory of Open Access Journals (Sweden)

    Luiz Carlos de Oliveira

    2001-09-01

    Full Text Available CONTEXT: There is still controversy as to the use and dosage of antimicrobial prophylaxis of the urinary infection associated with urethral catheterization in the post renal transplant period. OBJECTIVE: To determine whether patients develop urinary infection during short-term urethral catheterization after renal transplant without routine antimicrobial prophylaxis. DESIGN: Prospective study. SETTING: Kidney Transplantation Unit. SAMPLE: 20 patients submitted to non-complicated kidney transplant, with a normal urinary tract and no risk factors present regarding urinary infection. Aged 15 to 65 years. MAIN MEASUREMENTS: Before the transplant, material from the urethral meatus and urine were collected for culture. After the transplant, in the period during which the patient was with short-term urethral catheterization (4 to 5 days, material from the urethral meatus and urine from the bladder and the collecting bag were taken daily from all recipients for culture. RESULTS: There was a predominance of coagulase-negative Staphylococcus and S. viridans in the normal urethral meatus flora and in the first two days of urethral catheterization. After the second day, there was a predominance of E. coli and E. faecalis. Urinary infection did not occur during the period of urethral catheterization. In the follow up only one female patient (7% had asymptomatic bacteriuria caused by E.coli after the withdrawal of the urethral catheter. CONCLUSIONS: Infection urinary does not occur during the period of urethral catheterization in kidney post-transplant patients. Thus, antimicrobial prophylaxis is not recommended for these patients to prevent urinary infection.

  12. Native kidney post-transplant lymphoproliferative disorder in a non-renal transplant patient.

    Science.gov (United States)

    Araya, Carlos E; Mehta, Mansi B; González-Peralta, Regino P; Hunger, Stephen P; Dharnidharka, Vikas R

    2009-06-01

    PTLD is an important post-transplant complication. Although PTLD affects kidney allografts after renal transplantation, it has not been reported in native kidneys of other solid organ recipients. Herein, we report a child who underwent an orthotropic liver transplant for cryptogenic cholestatic hepatitis and developed fever, generalized lymphadenopathy, chronic EBV viremia, and lymphatic PTLD. Subsequently, she also developed gross hematuria and nephrotic range proteinuria. Kidney histology revealed EBV-positive mononuclear infiltrates within the renal parenchyma consistent with PTLD. Electron microscopy examination demonstrated subepithelial electron-dense deposits consistent with a membranous glomerulopathy pattern. The PTLD was successfully treated with reduced immunosuppression and cyclic cyclophosphamide, rituximab, and prednisone, but the renal disease progressed to end-stage renal failure within two yr. Repeat kidney histology showed chronic nephropathy and membranous glomerulopathy without PTLD infiltrates or detectable EBV staining, although chronic viremia persisted. To our knowledge, this is the first such child to be reported and highlights the importance of remaining vigilant for renal PTLD even in non-kidney organ recipients.

  13. Post-transplant development of C1q-positive HLA antibodies and kidney graft survival.

    Science.gov (United States)

    Piazza, Antonina; Poggi, Elvira; Ozzella, Giuseppina; Adorno, Domenico

    2013-01-01

    The development of de novo human leukocyte antigen (HLA) donor specific antibodies (DSA), detected by both cytotoxic or solid phase assays, was considered the major risk factor for allograft failure in kidney transplantation. However, it was shown that not all patients with persistent production of DSA suffered loss of their grafts. Modified Luminex-Single Antigen assays, able to identify C1q-fixing antibodies, represent a new strategy in assessing the clinical relevance of detected DSA. This study demonstrated that C1q-fixing capability of de novo DSA is a clinically relevant marker of worse outcome and inferior graft survival in kidney transplantation. In fact, our findings evidenced a very low graft survival only in the patients who developed DSA able to fix C1q during post-transplant course, while patients producing C1q-negative DSA had good graft survival, which was comparable to that found in our previous study for DSA-negative patients. Moreover, anti-HLA class II antibodies had a higher incidence than anti-HLA class I, and the ability to fix C1q was significantly more frequent among anti-DQ DSA than anti-DR DSA. Monitoring of de novo C1q-DSA production represents a useful, non-invasive tool for risk stratification and prediction of graft outcome in kidney transplantation.

  14. Severe right ventricular dysfunction is an independent predictor of pre- and post-transplant mortality among candidates for heart transplantation.

    Science.gov (United States)

    Ravis, Eleonore; Theron, Alexis; Mancini, Julien; Jaussaud, Nicolas; Morera, Pierre; Chalvignac, Virginie; Guidon, Catherine; Grisoli, Dominique; Gariboldi, Vlad; Riberi, Alberto; Habib, Gilbert; Mouly-Bandini, Annick; Collart, Frederic

    2017-03-01

    Heart transplantation is the gold-standard treatment for end-stage heart failure. However, the shortage of grafts has led to longer waiting times and increased mortality for candidates without priority. To study waiting-list and post-transplant mortality, and their risk factors among patients registered for heart transplantation without initial high emergency procedure. All patients registered on the heart transplantation waiting list (2004-2015) without initial high emergency procedure were included. Clinical, biological, echocardiographic and haemodynamic data were collected. Waiting list and 1-year post-transplant survival were analysed with a Kaplan-Meier model. Of 221 patients enrolled, 168 (76.0%) were men. Mean age was 50.0±12.0 years. Forty-seven patients died on the waiting list, resulting in mortality rates of 11.2±2.7% at 1 year, 31.9±5.4% at 2 years and 49.4±7.1% at 3 years. Median survival was 36.0±4.6 months. In the multivariable analysis, left ventricular ejection fractionright ventricular systolic dysfunction (HR: 2.89, 95% CI: 1.41-5.92; P=0.004) were associated with increased waiting-list mortality. The post-transplant survival rate was 73.1±4.4% at 1 year. Pretransplant severe right ventricular dysfunction and age>50 years were strong predictors of death after transplantation (HR: 5.38, 95% CI: 1.38-10.24 [P=0.020] and HR: 6.16, 95% CI: 1.62-9.32 [P=0.0130], respectively). Mortality among candidates for heart transplantation remains high. Patients at highest risk of waiting-list mortality have to be promoted, but without compromising post-transplant outcomes. For this reason, candidates with severe right ventricular dysfunction are of concern, because, for them, transplantation is hazardous. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  15. B cell subsets in atherosclerosis

    Directory of Open Access Journals (Sweden)

    Heather M. Perry

    2012-12-01

    Full Text Available Atherosclerosis, the underlying cause of heart attacks and strokes, is a chronic inflammatory disease of the artery wall. Immune cells, including lymphocytes modulate atherosclerotic lesion development through interconnected mechanisms. Elegant studies over the past decades have begun to unravel a role for B cells in atherosclerosis. Recent findings provide evidence that B cell effects on atherosclerosis may be subset-dependent. B-1a B cells have been reported to protect from atherosclerosis by secretion of natural IgM antibodies. Conventional B-2 B cells can promote atherosclerosis through less clearly defined mechanism that may involve CD4 T cells. Yet, there may be other populations of B cells within these subsets with different phenotypes altering their impact on atherosclerosis. Additionally, the role of B cell subsets in atherosclerosis may depend on their environmental niche and/or the stage of atherogenesis. This review will highlight key findings in the evolving field of B cells and atherosclerosis and touch on the potential and importance of translating these findings to human disease.

  16. [Health related quality of life and kidney transplantation: a comparison with population values at 6 months post-transplant].

    Science.gov (United States)

    Costa-Requena, Gema; Cantarell Aixendri, M Carmen; Rodriguez Urrutia, Amanda; Seron Micas, Daniel

    2014-05-06

    Transplantation is an effective treatment for end stage renal failure. The aim of this study was to compare patient's perceived health related quality of life (HRQoL) with population values, at one moth and 6 moths of kidney post-transplantation. The Questionnaire of Quality of Life in Kidney Disease was administered during the first month and also at the 6 months following transplantation. A comparison with the general population was done with the generic part of the questionnaire. In the statistical analyses, typical standardized scores were used. In this study 72 patients were included with a median age of 57 years. At the 6 month post-transplantation, the patient's HRQoL showed values that were similar to the general population. When we compared the HRQoL at the first month and at the 6 month post-transplantation, the differences of HRQoL were significant in all dimensions, except on the General health and Emotional role. At 6 moths after transplantation, there was an improvement in the perceived HRQoL that was similar to the general population. Copyright © 2013 Elsevier España, S.L. All rights reserved.

  17. Addressing post-transplant summer water stress in Pinus pinea and Quercus ilex seedlings

    Directory of Open Access Journals (Sweden)

    Pardos M

    2015-06-01

    Full Text Available In central Spain, post-transplant water stress produces high seedling mortality after the first summer following outplanting. Our study was designed to determine whether survival and performance of outplanted stone pine (Pinus pinea and holm oak (Quercus ilex seedlings in a burned area could be improved by summer irrigation and mulching and to identify whether there is a species-specific adaptive capacity to respond to treatment and environment. Seedlings were outplanted in March 2011 in 200 planting holes in an area of 1.1 ha. Mulch was added in June; irrigation started in July and was repeated every week until mid-September. The severity of the 2011 summer drought constrained growth rates and photosynthetic characteristics, mainly in the non-irrigated seedlings, whose survival at the end of the year after planting was approximately 2.5%. Stone pine and holm oak seedlings responded more to irrigation than to mulching in terms of shoot growth, biomass and survival. Furthermore, stone pine seedlings were found to be more responsive to the partial alleviation of summer drought than holm oak seedlings. Irrigation alone produced similar results to those obtained when both irrigation and mulching were employed. In conclusion, first year summer irrigation should be considered as a planned adaptation measure in the management of outplanted Mediterranean ecosystems, because once a gravimetrically measured soil moisture level as low as 2% is achieved seedling survival and physiological performance can be guaranteed. However, the repercussions for the potential persistence of both species in the area will not only be related to the recurrence and intensity of summer droughts but also to drought duration.

  18. Post-transplant lymphoproliferative disorders: implications for acquired immunodeficiency syndrome-associated malignancies.

    Science.gov (United States)

    Swinnen, L J

    2001-01-01

    Post-transplant lymphoproliferative disorders (PTLDs) comprise a histologic spectrum, ranging from hyperplastic-appearing lesions to frank non-Hodgkin's lymphoma or multiple myeloma histology. Multiple clones may coexist, each representing a discrete lymphomagenic event, a situation that is unique to immunodeficiency states. The incidence varies from 1% in renal recipients to 5% in heart recipients, but can be markedly increased by the use of anti-T-cell therapies or by T-cell depletion in bone marrow transplantation. PTLD continues to arise, even many years after transplantation, and late T-cell lymphomas have recently been recognized. Pretransplant Epstein-Barr virus (EBV) seronegativity increases risk to as high as 30%-50%. PTLD has a highly variable clinical picture; certain patterns are, however, seen. Reversibility of PTLD with reduction in immunosuppressives has long been recognized. Predicting reversibility has been difficult. The presence or absence of bcl-6 mutations has recently been identified as being of predictive value. Surgical resection can be curative. Cytotoxics, although problematic, can also be curative. Long-term remission has been achieved with anti CD21 and CD24 antibodies; efficacy has been reported for interferon alfa and for rituximab. In vitro expanded EBV-specific T cells have been effective as treatment and as prophylaxis in the setting of bone marrow transplantation. EBV viral load measured in blood appears to associate with the emergence of PTLD and may facilitate prophylactic studies. PTLD is a model of immunodeficiency-related EBV lymphomagenesis. Pathogenetic, therapeutic, and prophylactic insights gained from the study of PTLD are likely to be applicable to the acquired immunodeficiency syndrome setting.

  19. The clinical course and outcomes of post-transplantation diabetes mellitus after heart transplantation.

    Science.gov (United States)

    Cho, Min Soo; Choi, Hyo-In; Kim, In-Ok; Jung, Sung-Ho; Yun, Tae-Jin; Lee, Jae-Won; Kim, Min-Seok; Kim, Jae-Joong

    2012-12-01

    The aim of this study was to describe in more detail the predisposition, natural course, and clinical impact of post-transplantation diabetes mellitus (PTDM) after heart transplantation (HT). The characteristics and clinical outcomes of 54 patients with PTDM were compared with those of 140 patients without PTDM. The mean age of PTDM patients was significantly higher than controls (48.9 ± 9.3 vs 38.6 ± 13.3 yr, respectively, P = 0.001), and ischemic heart disease was a more common indication of HT (20.4% [11/54] vs 7.1% [10/140], respectively, P = 0.008). In multivariate analysis, only recipient age (odds ratio, 1.80; 95% confidence interval, 1.35-2.40; P = 0.001) was associated with PTDM development. In 18 patients (33%), PTDM was reversed during the follow-up period, and the reversal of PTDM was critically dependent on the time taken to develop PTDM (1.9 ± 1.0 months in the reversed group vs 14.5 ± 25.3 months in the maintained group, P = 0.005). The 5-yr incidence of late infection (after 6 months) was higher in the PTDM group than in the control group (30.4% ± 7.1% vs 15.4% ± 3.3%, respectively, P = 0.031). However, the 5-yr overall survival rate was not different (92.9% ± 4.1% vs 85.8% ± 3.2%, respectively, P = 0.220). In conclusion, PTDM after HT is reversible in one-third of patients and is not a critical factor in patient survival after HT.

  20. B-cell dysfunction and depletion using mycophenolate mofetil in a pediatric combined liver and kidney graft recipient.

    Science.gov (United States)

    Ganschow, R; Lyons, M; Kemper, M J; Burdelski, M

    2001-02-01

    The use of mycophenolate mofetil (MMF) in combination with cyclosporin A (CsA) and steroids is well established after kidney transplantation (Tx) in children. A 9-yr-old girl with primary hyperoxaluria type 1 and systemic oxalosis underwent a combined kidney and liver Tx at our institution. The post-operative immunosuppression consisted of CsA, prednisolone, and MMF. Four weeks post-transplant the girl suffered from a severe urinary tract infection caused by Pseudomonas aeruginosa, when the serum immunoglobulin G (IgG) concentration was found to be critically low (IVIG) substitution was necessary. There was no significant loss of immunoglobulins in the ascites and urine and no other medication with possible side-effects on B cells was given. We suggest that MMF can lead to suppressed IgG production by B cells and can cause a defective differentiation into mature B cells. In vitro studies demonstrated these effects of MMF on B cells, but no in vivo cases of this phenomenon have been reported. B-cell counts and serum IgG concentrations returned to normal values after discontinuing the MMF. As we can assume that the observed B-cell dysfunction and depletion were MMF related, we suggest that serum IgG concentrations should be monitored when MMF is used after solid-organ Tx.

  1. Rituximab in Treating Patients Undergoing Donor Peripheral Blood Stem Cell Transplant for Relapsed or Refractory B-cell Lymphoma

    Science.gov (United States)

    2015-11-23

    B-cell Adult Acute Lymphoblastic Leukemia; B-cell Childhood Acute Lymphoblastic Leukemia; B-cell Chronic Lymphocytic Leukemia; Childhood Burkitt Lymphoma; Childhood Diffuse Large Cell Lymphoma; Childhood Immunoblastic Large Cell Lymphoma; Cutaneous B-cell Non-Hodgkin Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Intraocular Lymphoma; Nodal Marginal Zone B-cell Lymphoma; Post-transplant Lymphoproliferative Disorder; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Hodgkin Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Childhood Acute Lymphoblastic Leukemia; Recurrent Childhood Grade III Lymphomatoid Granulomatosis; Recurrent Childhood Large Cell Lymphoma; Recurrent Childhood Lymphoblastic Lymphoma; Recurrent Childhood Small Noncleaved Cell 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 Small Lymphocytic Lymphoma; Recurrent/Refractory Childhood Hodgkin Lymphoma; Refractory Chronic Lymphocytic Leukemia; Refractory Hairy Cell Leukemia; Small Intestine Lymphoma; Splenic Marginal Zone Lymphoma; Testicular Lymphoma; Waldenström Macroglobulinemia

  2. [Epstein-Barr virus (EBV) in Russia: infection of the population and analysis of the LMP1 gene variants in patients with EBV-associated pathologies and healthy individuals].

    Science.gov (United States)

    Goncharova, E V; Senyuta, N B; Smirnova, K V; Shcherbak, L N; Gurtsevich, V E

    2015-01-01

    The Epstein-Barr virus, widespread herpesvirus among the population of the planet, is also the etiologic agent for a number of malignancies. One of the oncoproteins encoded by the virus, the latent membrane protein 1 (LMP1I), through activation of the complex signaling pathways is involved in the processes of cell immortalization and transformation. The goal of this work was to study the level of the EBV infection in Russian population and LMP1 polymorphism in patients with benign and malignant EBV-associated diseases and healthy virus carriers. Studies have shown that by the age of 5-9 years the percentage of the infected persons and the level of antibody titers reaches almost the maximum values. With the age, virus specific antibody titers are decreased (with a high percentage of infected persons) and increased again in groups of older persons. The analysis of the nucleotide sequences of the gene LMP1 translated in amino acid (aa) sequences unexpectedly revealed the dominance a low divergent variant LMP1 B95.8A not only in healthy individuals but also in patients with all forms of EBV-associated diseases. Highly divergent variants Ch1 and Med +, containing a deletion of 10 aa, and characterized by elevated transforming activity more often were detected in the tumor tissue samples than in the blood samples/mouth washes of the same patients. Detection of highly transforming variant LMP1 Ch1 in blood samples of healthy individuals indicates that this analog of Chinese variant Cao may persist in any population and is not necessarily associated with the occurrence of the EBV-associated disorders.

  3. What is the impact of immunosuppressive treatment on the post-transplant renal osteopathy?

    Science.gov (United States)

    Blaslov, Kristina; Katalinic, Lea; Kes, Petar; Spasovski, Goce; Smalcelj, Ruzica; Basic-Jukic, Nikolina

    2014-05-01

    Although glucocorticoid therapy is considered to be the main pathogenic factor, a consistent body of evidence suggests that other immunosuppressants might also play an important role in the development of the post-transplant renal osteopathy (PRO) through their pleiotropic pharmacological effects. Glucocorticoids seem to induce osteoclasts' activity suppressing the osteoblasts while data regarding other immunosuppressive drugs are still controversial. Mycophenolate mofetil and azathioprine appear to be neutral regarding the bone metabolism. However, the study analyzing any independent effect of antimetabolites on bone turnover has not been conducted yet. Calcineurin inhibitors (CNIs) induce trabecular bone loss in rodent, with contradictory results in renal transplant recipients. Suppression of vitamin D receptor is probably the underlying mechanism of renal calcium wasting in renal transplant recipients receiving CNI. In spite of an increased 1,25(OH)2 vitamin D level, the kidney is not able to reserve calcium, suggesting a role of vitamin D resistance that may be related to bone loss. More efforts should be invested to determine the role of CNI in PRO. In particular, data regarding the role of mammalian target of rapamycin inhibitors (mTORi), such as sirolimus and everolimus, in the PRO development are still controversial. Rapamycin markedly decreases bone longitudinal growth as well as callus formation in experimental models, but also lowers the rate of bone resorption markers and glomerular filtration in clinical studies. Everolimus potently inhibits primary mouse and human osteoclast activity as well as the osteoclast differentiation. It also prevents the ovariectomy-induced loss of cancellous bone by 60 %, an effect predominantly associated with a decreased osteoclast-mediated bone resorption, resulting in a partial preservation of the cancellous bone. At present, there is no clinical study analyzing the effect of everolimus on bone turnover in renal

  4. ROLE OF PRE- AND POST-TRANSPLANT FACTORS IN THE DEVELOPMENT OF CORONARY DISEASE OF THE TRANSPLANT HEART

    Directory of Open Access Journals (Sweden)

    E. K. Kurlianskaya

    2015-01-01

    Full Text Available Aim: to assess the relationship between preand post-transplantation factors and degree of coronary artery lesion, reported by intravascular ultrasound study (IVUS in patients who underwent orthotopic heart transplantation (OHT surgery. Materials and methods. The study comprised of 27 patients who underwent OHT more than 2 years before. The age of patients was 46,8 ± 10,4 years old. All of them were preoperatively classified by HLA system. All patients received transthoracic echocardiography at terms of 1, 6, 12 and 24 months after OHT. Coronary angiography (CAG and IVUS were performed at 24 ± 6 months. Results. In CAG none of the patients showed angiographic signs of CA stenosis, but changes of various degrees were detected by IVUS. Results obtained by IVUS were clustered to select two groups with different degree of coronary artery lesion. The donor’s age in Group 2 was evidently higher compared to Group 1 (34,77 ± 1,03 and 40,00 ± 2,04 years, respectively, p = 0,043. Donor-recipient coincidence frequency was lower in group with significant CA lesion (by 2,36, р = 0,003. The number of cardiac surgeries performed prior to OHT was higher in Group 2 (by 2,8, р = 0,008. Post-transplant factor analysis showed that the number of diabetes mellitus (DM cases revealed after transplantation was more frequent in Group 2 (by 3,2 vs Group 1, р = 0,021. Conclusion. The degree of CA lesion according to IVUS at 24-month period after OTH was associated with several post-transplant factors, which were the presence of cardiac surgical interventions before transplantation, low HLA donor-recipient coincidence frequency, and donor’s age. The more significant CA lesion is, the more cases of DM after OHT occur. 

  5. Post-transplant anti-HLA class II antibodies as risk factor for late kidney allograft failure

    OpenAIRE

    Campos,E.F.; Tedesco-Silva, H.; P.G. Machado; Franco., M; J.O. Medina-Pestana; Gerbase-Delima, Maria

    2006-01-01

    The purpose of this study was to prospectively analyze the relationship between the post-transplant anti-HLA class I and/or class II panel reactive antibodies and graft failure due to chronic allograft nephropathy (CAN). We studied 512 first kidney recipients transplanted at a single center, with a graft functioning for at least 3 years. A single blood sample was collected from each patient for antibody evaluation. the median posttransplant time after blood collection was 4.4 years and did no...

  6. Molecular programming of B cell memory.

    Science.gov (United States)

    McHeyzer-Williams, Michael; Okitsu, Shinji; Wang, Nathaniel; McHeyzer-Williams, Louise

    2011-12-09

    The development of high-affinity B cell memory is regulated through three separable phases, each involving antigen recognition by specific B cells and cognate T helper cells. Initially, antigen-primed B cells require cognate T cell help to gain entry into the germinal centre pathway to memory. Once in the germinal centre, B cells with variant B cell receptors must access antigens and present them to germinal centre T helper cells to enter long-lived memory B cell compartments. Following antigen recall, memory B cells require T cell help to proliferate and differentiate into plasma cells. A recent surge of information - resulting from dynamic B cell imaging in vivo and the elucidation of T follicular helper cell programmes - has reshaped the conceptual landscape surrounding the generation of memory B cells. In this Review, we integrate this new information about each phase of antigen-specific B cell development to describe the newly unravelled molecular dynamics of memory B cell programming.

  7. Responses to recipient and donor B cells by genetically donor T cells from human haploidentical chimeras

    Energy Technology Data Exchange (ETDEWEB)

    Schiff, S.; Sampson, H.; Buckley, R.

    1986-03-01

    Following administration of haploidentical stem cells to infants with severe combined immunodeficiency (SCID), mature T cells of donor karyotype appear later in the recipient without causing graft-versus-host disease. To investigate the effect of the host environment on the responsiveness of these genetically donor T cells, blood B and T lymphocytes from 6 SCID recipients, their parental donors and unrelated controls were purified by double SRBC rosetting. T cells were stimulated by irradiated B cells at a 1:1 ratio in 6 day cultures. Engrafted T cells of donor karyotype gave much smaller responses to irradiated genetically recipient B cells than did fresh donor T cells. Moreover, engrafted T cells of donor karyotype from two of the three SCIDs who are longest post-transplantation responded more vigorously (14,685 and 31,623 cpm) than fresh donor T cells (5141 and 22,709 cpm) to donor B cells. These data indicate that T lymphocytes which have matured from donor stem cells in the recipient microenvironment behave differently from those that have matured in the donor.

  8. Epidemiology of post-transplant malignancy in Chinese renal transplant recipients: a single-center experience and literature review.

    Science.gov (United States)

    Zhang, Jian; Ma, Linlin; Xie, Zelin; Guo, Yuwen; Sun, Wen; Zhang, Lei; Lin, Jun; Xiao, Jing; Zhu, Yichen; Tian, Ye

    2014-07-01

    This study investigated the incidence and types of post-transplant malignancy in Chinese renal transplant recipients and the risk factors associated with malignancy. Data from 3,462 patients who underwent renal transplantation at Beijing Friendship Hospital were combined with data from 26 previous reports describing malignancy rates in 27,170 Chinese renal transplant recipients. Between 1974 and 2014, 179/3,462 (5.17 %) patients who underwent renal transplantation at our center developed malignancy. The most common site of malignancy was the urinary system, and the most common type was urothelial transitional cell carcinoma. Combined data from our center and previous reports showed malignancy in 671 (2.19 %) Chinese renal transplant recipients. The ten most common malignancies were urothelial transitional cell carcinoma (n = 283), hepatocellular carcinoma (n = 68), gastrointestinal cancer (n = 63), renal cell carcinoma (n = 42), lymphoma (n = 42), lung cancer (n = 28), breast cancer (n = 19), skin cancer (n = 18), Kaposi's sarcoma (n = 12), and cervical cancer (n = 10). The incidence of post-transplant malignancy in renal transplant recipients was lower in China than the reported rates in other countries, and the most common sites of malignancy were the urinary and digestive system. The relative frequency of malignancy sites differed between northern and southern China. Renal transplant recipients on long-term immunosuppressive therapy should receive careful follow-up, including annual or biannual screening for malignancy in high-risk individuals.

  9. 91例EB病毒相关疾病儿童血浆EB病毒DNA的检测%Determination of plasma EBV DNA in 91 children with EBV-associated diseases

    Institute of Scientific and Technical Information of China (English)

    段红梅; 姚瑶; 谢正德; 闫静; 胡英慧; 幺远; 周玲; 申昆玲

    2009-01-01

    Objective To determine the plasma level of Epstein-Barr virus ( EBV) DNA in children with EBV-associated diseases, and to investigate the dynamic changes of EBV DNA level after initial infection as well as the relationship between EBV-DNA level and the diseases severity. Methods The subjects consisted of 73 children with primary EBV infection (infectious mononucleosis, pneumonia,etc. ) and 18 children with severe EBV-associated diseases (chronic active EBV infection, hemophagocytic lymphohistiocytosis, etc. ). The plasma EBV DNA level was detected by a real-time PCR assay. Results The plasma EBV DNA level decreased with the infection time in children with primary EBV infection. Two weeks after infection, plasma EBV DNA was almost undetectable. The positive rate of plasma EBV DNA in children with severe EBV-associated diseases increased significantly when compared with that in children with primary EBV infection (89% vs 16% ; P < 0.05). Conclusions The level of EBV replication may be reduced with the infection time. Dynamic determination of blood EBV DNA is useful for the evaluation of disease severity in children with EBV infection.%目的 了解EB病毒(EBV)感染患儿外周血血浆中游离EBV DNA的拷贝数,确定EBV原发感染后外周血血浆中EBV游离DNA的拷贝数与发病天数及病情轻重的关系.方法 应用荧光定量PCR方法,测定73例EBV原发感染和18例EBV相关重症疾病患儿外周血血浆中EBV游离DNA.结果 ①原发EBV感染患儿外周血血浆中EBV游离DNA随发病天数呈下降趋势,发病2周后很难检测到.②EBV相关重症疾病组患儿外周血血浆中EBV游离DNA阳性率明显高于原发EBV感染组,差异有显著性(89%vs 16%,P<0.05).结论 原发EBV感染后随病程天数的增加,病毒复制水平逐渐下降.血浆中EBV游离DNA检测对评价EBV相关疾病的严重程度有一定参考价值.

  10. Post transplant urinary tract infection in Autosomal dominant polycystic kidney disease a perpetual diagnostic dilema - 18-fluorodeoxyglucose - Positron emission computerized tomography - A valuable tool.

    Science.gov (United States)

    Sainaresh, Vv; Jain, Sh; Patel, Hv; Shah, Pr; Vanikar, Av; Trivedi, Hl

    2011-04-01

    Urinary tract infection (UTI) is the most common infection contracted by renal allograft recipients. In patients of autosomal dominant polycystic kidney disease (ADPKD), cyst infection presents a complex diagnostic and therapeutic challenge especially in the post transplant period. Accurate diagnosis forms the cornerstone in salvaging the graft from potentially catastrophic outcome. We describe a case of xanthogranulomatous pyelonephritis (XPN) in the native kidney in a patient of post transplant ADPKD which presented as frequently relapsing UTI with graft dysfunction where in accurate diagnosis was made possible with the aid of 18-fluorodeoxyglucose (FDG) - Positron emission computerized tomography (PET/CT).

  11. Epstein-Barr virus (EBV) gene expression in interstitial pneumonitis in Brazilian human immunodeficiency virus-1-infected children: is EBV associated or not?

    Science.gov (United States)

    Toro, Adyléia A D C; Altemani, Albina M A; da Silva, Marcos T N; Morcillo, André M; Vilela, Maria Marluce S

    2010-01-01

    To gain further knowledge on the subject we evaluated Epstein-Barr virus (EBV) gene expression and TCD4+, TCD8+, and B lymphocyte counts in lung tissue samples from 20 human immunodeficiency virus (HIV)-infected children with chronic lung disease. Twenty HIV-1 infected children with chronic pulmonary disease underwent open lung biopsy to define the diagnosis. Histological section of this material was submitted to nonisotopic in situ hybridization (ISH) using EBV-encoded RNA (EBER) 1/2 probes and TCD4+, TCD8+, and CD20+ B-cell counts by immunohistochemistry. The histology of 16 out of the 20 children (median age 53.5 months) proved to be examples of pulmonary lymphoid hyperplasia/lymphoid interstitial pneumonitis (PLH/LIP) complex, 13 of which were EBER positive, but no significant association was found (Fisher exact test P = 0.439). Four patients had non-LIP diseases (3, nonspecific interstitial pneumonia; 1, diffuse advanced alveolar damage), two being EBER negative. Nineteen children showed a predominant T-CD8+ cell response (CD4+/CD8+ PLH/LIP complex, but without significant difference between EBER positive and EBER negative samples. EBV gene expression was detected in the majority of the lung samples but without significant association with PLH/LIP complex or with TCD4+, TCD8+, B cells and the TCD4+/TCD8+ ratio. Regarding the pattern of lung disease in HIV-1 infected children, associated or not to EBV, the findings are of importance concerning the possible role of EBV in the pathogenesis of PLH/LIP.

  12. HIV-associated memory B cell perturbations.

    Science.gov (United States)

    Hu, Zhiliang; Luo, Zhenwu; Wan, Zhuang; Wu, Hao; Li, Wei; Zhang, Tong; Jiang, Wei

    2015-05-21

    Memory B-cell depletion, hyperimmunoglobulinemia, and impaired vaccine responses are the hallmark of B cell perturbations inhuman immunodeficiency virus (HIV) disease. Although B cells are not the targets for HIV infection, there is evidence for B cell, especially memory B cell dysfunction in HIV disease mediated by other cells or HIV itself. This review will focus on HIV-associated phenotypic and functional alterations in memory B cells. Additionally, we will discuss the mechanism underlying these perturbations and the effect of anti-retroviral therapy (ART) on these perturbations.

  13. Characterization of Epstein-Barr virus (EBV) BZLF1 gene promoter variants and comparison of cellular gene expression profiles in Japanese patients with infectious mononucleosis, chronic active EBV infection, and EBV-associated hemophagocytic lymphohistiocytosis.

    Science.gov (United States)

    Imajoh, Masayuki; Hashida, Yumiko; Murakami, Masanao; Maeda, Akihiko; Sato, Tetsuya; Fujieda, Mikiya; Wakiguchi, Hiroshi; Daibata, Masanori

    2012-06-01

    Epstein-Barr virus (EBV) genotypes can be distinguished based on gene sequence differences in EBV nuclear antigens 2, 3A, 3B, and 3C, and the BZLF1 promoter zone (Zp). EBV subtypes and BZLF1 Zp variants were examined in Japanese patients with infectious mononucleosis, chronic active EBV infection, and EBV-associated hemophagocytic lymphohistiocytosis. The results of EBV typing showed that samples of infectious mononucleosis, chronic active EBV infection, and EBV-associated hemophagocytic lymphohistiocytosis all belonged to EBV type 1. However, sequencing analysis of BZLF1 Zp found three polymorphic Zp variants in the same samples. The Zp-P prototype and the Zp-V3 variant were both detected in infectious mononucleosis and chronic active EBV infection. Furthermore, a novel variant previously identified in Chinese children with infectious mononucleosis, Zp-V1, was also found in 3 of 18 samples of infectious mononucleosis, where it coexisted with the Zp-P prototype. This is the first evidence that the EBV variant distribution in Japanese patients resembles that found in other Asian patients. The expression levels of 29 chronic active EBV infection-associated cellular genes were also compared in the three EBV-related disorders, using quantitative real-time reverse transcription polymerase chain reaction analysis. Two upregulated genes, RIPK2 and CDH9, were identified as common specific markers for chronic active EBV infection in both in vitro and in vivo studies. RIPK2 activates apoptosis and autophagy, and could be responsible for the pathogenesis of chronic active EBV infection.

  14. B cell activating factor (BAFF) selects IL-10(-)B cells over IL-10(+)B cells during inflammatory responses.

    Science.gov (United States)

    Ma, Ning; Zhang, Yu; Liu, Qilin; Wang, Zhiding; Liu, Xiaoling; Zhu, Gaizhi; Yu, Dandan; Han, Gencheng; Chen, Guojiang; Hou, Chunmei; Wang, Tianxiao; Ma, Yuanfang; Shen, Beifen; Li, Yan; Xiao, He; Wang, Renxi

    2017-02-12

    B cell activating factor (BAFF) regulates B cell maturation, survival, function, and plays a critical pathogenic role in autoimmune diseases. It remains unclear how BAFF affects IL-10(-)B cells versus regulatory B cells (Bregs) in inflammatory responses. In this study, we found that IL-10-expressing Bregs decreased in lupus-prone MRL/lpr mice and experimental allergic encephalomyelitis (EAE) mice. On blockade of the effects of BAFF with TACI-IgG, IL-10(+) Bregs were upregulated in MRL/lpr and EAE mice. In addition, BAFF expanded IL-10(+)B cells over IL-10(-)B cells under noninflammatory conditions in vitro, whereas it expanded IL-10(-)B cells over IL-10(+)B cells during inflammatory responses, such as stimulation with autoantigen and LPS. Finally, the selection of IL-10(-)B cells over IL-10(+)B cells by BAFF was dependent on BAFF receptors (BAFFR, TACI, and BCMA) that were upregulated by inflammatory responses. This study suggests that BAFF selects IL-10(-)B cells over IL-10(+) regulatory B cells via BAFF receptors in inflammatory responses.

  15. Multiple Curricula for B Cell Developmental Programming.

    Science.gov (United States)

    Rothenberg, Ellen V

    2016-09-20

    B-1 B cells differ from conventional B-2 B cells functionally, but how these differences relate to the ontogeny of these lineages has been unclear. Two recent Immunity articles, Kristiansen et al. (2016) and Montecino-Rodriguez et al. (2016), now provide insight into the origins of B-1 and B-2 B cells, revealing a multi-layered developmental program and successive waves of B cell precursors.

  16. Ikaros in B cell development and function

    Institute of Scientific and Technical Information of China (English)

    MacLean; Sellars; Philippe; Kastner; Susan; Chan

    2011-01-01

    The zinc finger transcription factor,Ikaros,is a central regulator of hematopoiesis.It is required for the development of the earliest B cell progenitors and at later stages for VDJ recombination and B cell receptor expression.Mature B cells rely on Ikaros to set the activation threshold for various stimuli,and to choose the correct antibody isotype during class switch recombination.Thus,Ikaros contributes to nearly every level of B cell differentiation and function.

  17. The B cell transcription program mediates hypomethylation and overexpression of key genes in Epstein-Barr virus-associated proliferative conversion.

    Science.gov (United States)

    Hernando, Henar; Shannon-Lowe, Claire; Islam, Abul B; Al-Shahrour, Fatima; Rodríguez-Ubreva, Javier; Rodríguez-Cortez, Virginia C; Javierre, Biola M; Mangas, Cristina; Fernández, Agustín F; Parra, Maribel; Delecluse, Henri-Jacques; Esteller, Manel; López-Granados, Eduardo; Fraga, Mario F; López-Bigas, Nuria; Ballestar, Esteban

    2013-01-15

    Epstein-Barr virus (EBV) infection is a well characterized etiopathogenic factor for a variety of immune-related conditions, including lymphomas, lymphoproliferative disorders and autoimmune diseases. EBV-mediated transformation of resting B cells to proliferating lymphoblastoid cells occurs in early stages of infection and is an excellent model for investigating the mechanisms associated with acquisition of unlimited growth. We investigated the effects of experimental EBV infection of B cells on DNA methylation profiles by using high-throughput analysis. Remarkably, we observed hypomethylation of around 250 genes, but no hypermethylation. Hypomethylation did not occur at repetitive sequences, consistent with the absence of genomic instability in lymphoproliferative cells. Changes in methylation only occurred after cell divisions started, without the participation of the active demethylation machinery, and were concomitant with acquisition by B cells of the ability to proliferate. Gene Ontology analysis, expression profiling, and high-throughput analysis of the presence of transcription factor binding motifs and occupancy revealed that most genes undergoing hypomethylation are active and display the presence of NF-κB p65 and other B cell-specific transcription factors. Promoter hypomethylation was associated with upregulation of genes relevant for the phenotype of proliferating lymphoblasts. Interestingly, pharmacologically induced demethylation increased the efficiency of transformation of resting B cells to lymphoblastoid cells, consistent with productive cooperation between hypomethylation and lymphocyte proliferation. Our data provide novel clues on the role of the B cell transcription program leading to DNA methylation changes, which we find to be key to the EBV-associated conversion of resting B cells to proliferating lymphoblasts.

  18. Quantitative Epstein-Barr virus (EBV) serology in lung transplant recipients with primary EBV infection and/or post-transplant lymphoproliferative disease

    NARCIS (Netherlands)

    Verschuuren, E; van der Bij, W; de Boer, W; Timens, W; Middeldorp, J; The, TH

    2003-01-01

    The Epstein-Barr virus (EBV)-specific antibody response was studied in lung transplant patients to assess their value in the diagnosis and prognosis of post-transplant lymphoproliferative disease. Recently developed synthetic peptides representing Epstein-Barr nuclear antigen-1 (EBNA-1), diffuse ear

  19. Post-transplant reactions of mycorrhizal and mycorrhiza-free seedlings of Leucaena leucocephala to pH changes in an Oxisol and Ultisol of Hawaii

    Science.gov (United States)

    M. Habte; G. Diarra; P.G. Scowcroft

    2011-01-01

    The extent to which pretransplant colonization of seedlings with the arbuscular mycorrhizal fungus (AMF) Glomus aggregatum Schenck and Smith emend. Koske could enhance the post-transplant growth of two cultivars of Leucaena leucocephala (Lam.) de Wit (cv. K-8 and cv. K-636) in Al- and Mn-rich acid soils was evaluated in a...

  20. Early T Cell Recognition of B Cells following Epstein-Barr Virus Infection: Identifying Potential Targets for Prophylactic Vaccination.

    Directory of Open Access Journals (Sweden)

    Jill M Brooks

    2016-04-01

    Full Text Available Epstein-Barr virus, a B-lymphotropic herpesvirus, is the cause of infectious mononucleosis, has strong aetiologic links with several malignancies and has been implicated in certain autoimmune diseases. Efforts to develop a prophylactic vaccine to prevent or reduce EBV-associated disease have, to date, focused on the induction of neutralising antibody responses. However, such vaccines might be further improved by inducing T cell responses capable of recognising and killing recently-infected B cells. In that context, EBNA2, EBNA-LP and BHRF1 are the first viral antigens expressed during the initial stage of B cell growth transformation, yet have been poorly characterised as CD8+ T cell targets. Here we describe CD8+ T cell responses against each of these three "first wave" proteins, identifying target epitopes and HLA restricting alleles. While EBNA-LP and BHRF1 each contained one strong CD8 epitope, epitopes within EBNA2 induced immunodominant responses through several less common HLA class I alleles (e.g. B*3801 and B*5501, as well as subdominant responses through common class I alleles (e.g. B7 and C*0304. Importantly, such EBNA2-specific CD8+ T cells recognised B cells within the first day post-infection, prior to CD8+ T cells against well-characterised latent target antigens such as EBNA3B or LMP2, and effectively inhibited outgrowth of EBV-transformed B cell lines. We infer that "first wave" antigens of the growth-transforming infection, especially EBNA2, constitute potential CD8+ T cell immunogens for inclusion in prophylactic EBV vaccine design.

  1. Cloning non-transformed sheep B cells.

    Science.gov (United States)

    Griebel, P J; Beskorwayne, T; Godson, D L; Popowych, Y; Hein, W

    2000-04-03

    The capacity to clone B cells and establish permanent B cell lines has greatly facilitated a wide variety of studies characterising the growth, differentiation, and gene expression of murine and human B cells. Similar investigations of B cell biology for other species have been severely restricted by an inability to culture or clone B cells. This is the first report of a method to clone non-transformed sheep B cells using a culture system based on murine CD154 and a combination of human gamma chain-common cytokines. Sheep Peyer's patch B cells were cultured for 120 days and then cloned by limiting dilution culture. The parental B cell culture contained both surface immunoglobulin (sIg)M(+) and sIgG1(+) B cells and both types of B cell were cloned. Clonality was confirmed by PCR analysis of Ig heavy chain (HC) and light chain (LC) expression and DNA sequencing of HC V genes. There was agreement between the PCR and flow cytometric analyses of HC isotype expression on the B cell clones but the available monoclonal antibodies specific for sheep lambda and kappa LC did not react with all clones. Soluble Ig was detected in the culture supernatant of sIgG1(+) clones but not sIgM(+) clones. The B cell clones remained dependent upon CD154 and gamma chain-common cytokine co-stimulation for sustained growth and maintained stable Ig expression. The cloning of non-transformed sheep B cells should provide a valuable tool for studying sheep B cell biology, establishing Ig HC- and LC-specific monoclonal antibodies, analysing the B cell Ig repertoire, and may be used to produce sheep monoclonal antibodies.

  2. HCV Infection and B-Cell Lymphomagenesis

    Directory of Open Access Journals (Sweden)

    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.

  3. B Cell Autonomous TLR Signaling and Autoimmunity

    Science.gov (United States)

    Meyer-Bahlburg, Almut; Rawlings, David J

    2009-01-01

    B cells play a central role in the pathogenesis of multiple autoimmune diseases and the recognition of importance of B cells in these disorders has grown dramatically in association with the remarkable success of B-cell depletion as a treatment for autoimmunity. The precise mechanisms that promote alterations in B cell tolerance remain incompletely defined. There is increasing evidence, however, that TLRs play a major role in these events. Stimulation of B cells via the TLR pathway not only leads to an increase in antibody production but also promotes additional changes including cytokine production and upregulation of activation markers increasing the effectiveness of B cells as APCs. Understanding the role of TLRs in systemic autoimmunity will not only provide insight into the disease pathogenesis but may also lead to the development of novel therapies. This article gives an overview of TLR signaling in B cells and the possible involvement of such signals in autoimmune diseases. PMID:18295736

  4. Memory B cells in mouse models.

    Science.gov (United States)

    Bergmann, B; Grimsholm, O; Thorarinsdottir, K; Ren, W; Jirholt, P; Gjertsson, I; Mårtensson, I-L

    2013-08-01

    One of the principles behind vaccination, as shown by Edward Jenner in 1796, and host protection is immunological memory, and one of the cells central to this is the antigen-experienced memory B cell that responds rapidly upon re-exposure to the initiating antigen. Classically, memory B cells have been defined as progenies of germinal centre (GC) B cells expressing isotype-switched and substantially mutated B cell receptors (BCRs), that is, membrane-bound antibodies. However, it has become apparent over the last decade that this is not the only pathway to B cell memory. Here, we will discuss memory B cells in mice, as defined by (1) cell surface markers; (2) multiple layers; (3) formation in a T cell-dependent and either GC-dependent or GC-independent manner; (4) formation in a T cell-independent fashion. Lastly, we will touch upon memory B cells in; (5) mouse models of autoimmune diseases.

  5. Antigen-specific memory B cell development.

    Science.gov (United States)

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

    2005-01-01

    Helper T (Th) cell-regulated B cell immunity progresses in an ordered cascade of cellular development that culminates in the production of antigen-specific memory B cells. The recognition of peptide MHC class II complexes on activated antigen-presenting cells is critical for effective Th cell selection, clonal expansion, and effector Th cell function development (Phase I). Cognate effector Th cell-B cell interactions then promote the development of either short-lived plasma cells (PCs) or germinal centers (GCs) (Phase II). These GCs expand, diversify, and select high-affinity variants of antigen-specific B cells for entry into the long-lived memory B cell compartment (Phase III). Upon antigen rechallenge, memory B cells rapidly expand and differentiate into PCs under the cognate control of memory Th cells (Phase IV). We review the cellular and molecular regulators of this dynamic process with emphasis on the multiple memory B cell fates that develop in vivo.

  6. Rationale for B cell targeting in SLE

    Science.gov (United States)

    Sanz, Iñaki

    2014-01-01

    B cells are central pathogenic players in Systemic Lupus Erythematosus and multiple other autoinmune diseases through antibody production as well as antibody independent functiona. At the same time, B cells are known to play important regulatory functions that may protect against autoimmune manifestations. Yet, the functional role of different B cell populations and their contribution to disease remain to be understood. The advent of agents that specifically target B cells, in particular anti-CD20 and ant-BLyS antibodies, have demonstrated the efficacy of this approach for the treatment of human autoimmunity. The analysis of patients treated with these and other B cell agents provide a unique opportunity to understand the correlates of clinical response and the significance of different B cell subsets. Here we discuss this information and how it could be used to better understand SLE and improve the rational design of B cell directed therapies in this disease. PMID:24763533

  7. Long-term use of amiodarone before heart transplantation significantly reduces early post-transplant atrial fibrillation and is not associated with increased mortality after heart transplantation

    Directory of Open Access Journals (Sweden)

    Rivinius R

    2016-02-01

    Full Text Available Rasmus Rivinius,1 Matthias Helmschrott,1 Arjang Ruhparwar,2 Bastian Schmack,2 Christian Erbel,1 Christian A Gleissner,1 Mohammadreza Akhavanpoor,1 Lutz Frankenstein,1 Fabrice F Darche,1 Patrick A Schweizer,1 Dierk Thomas,1 Philipp Ehlermann,1 Tom Bruckner,3 Hugo A Katus,1 Andreas O Doesch1 1Department of Cardiology, Angiology and Pneumology, 2Department of Cardiac Surgery, Heidelberg University Hospital, 3Institute for Medical Biometry and Informatics, University of Heidelberg, Heidelberg, Germany Background: Amiodarone is a frequently used antiarrhythmic drug in patients with end-stage heart failure. Given its long half-life, pre-transplant use of amiodarone has been controversially discussed, with divergent results regarding morbidity and mortality after heart transplantation (HTX.Aim: The aim of this study was to investigate the effects of long-term use of amiodarone before HTX on early post-transplant atrial fibrillation (AF and mortality after HTX.Methods: Five hundred and thirty patients (age ≥18 years receiving HTX between June 1989 and December 2012 were included in this retrospective single-center study. Patients with long-term use of amiodarone before HTX (≥1 year were compared to those without long-term use (none or <1 year of amiodarone. Primary outcomes were early post-transplant AF and mortality after HTX. The Kaplan–Meier estimator using log-rank tests was applied for freedom from early post-transplant AF and survival.Results: Of the 530 patients, 74 (14.0% received long-term amiodarone therapy, with a mean duration of 32.3±26.3 months. Mean daily dose was 223.0±75.0 mg. Indications included AF, Wolff–Parkinson–White syndrome, ventricular tachycardia, and ventricular fibrillation. Patients with long-term use of amiodarone before HTX had significantly lower rates of early post-transplant AF (P=0.0105. Further, Kaplan–Meier analysis of freedom from early post-transplant AF showed significantly lower rates of AF in this

  8. B-Cell Hematologic Malignancy Vaccination Registry

    Science.gov (United States)

    2016-12-28

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

  9. Post-transplant anti-HLA class II antibodies as risk factor for late kidney allograft failure.

    Science.gov (United States)

    Campos, E F; Tedesco-Silva, H; Machado, P G; Franco, M; Medina-Pestana, J O; Gerbase-DeLima, M

    2006-10-01

    The purpose of this study was to prospectively analyze the relationship between the post-transplant anti-HLA class I and/or class II panel reactive antibodies and graft failure due to chronic allograft nephropathy (CAN). We studied 512 first kidney recipients transplanted at a single center, with a graft functioning for at least 3 years. A single blood sample was collected from each patient for antibody evaluation. The median posttransplant time after blood collection was 4.4 years and did not differ between patients with (n = 91) or without anti-HLA antibodies (n = 421). Female gender, pregnancies and blood transfusions were associated with the presence of anti-HLA class I antibodies. Graft function deterioration was associated with anti-HLA class II antibodies. Multivariate analysis showed independent association for creatinine levels (RR = 7.5), acute rejection (RR = 2.6), recipient male gender (RR = 3.6) and anti-HLA class II antibodies (RR = 2.9) and CAN-associated graft loss. In conclusion, the presence of anti-HLA class II antibodies conferred a risk for graft loss before a decline in renal function and increased the risk of graft failure in patients who already had a decline in graft function. Thus, anti-HLA class II antibody monitoring is a useful tool for the management of long-term kidney recipients.

  10. Impact of graft steatosis on the post-transplantation biliary complications for living donor liver transplant recipients in China.

    Science.gov (United States)

    Li, Hong-Yu; Wei, Yong-Gang; Li, Bo; Yan, Lv-Nan; Wen, Tian-Fu; Zhao, Ji-Chun; Xu, Ming-Qing; Wang, Wen-Tao; Ma, Yu-Kui; Yang, Jia-Yin

    2012-06-01

    After living donor liver transplantation (LDLT), the prevalence of complications related to the biliary system is 6-35%. In spite of great improvements in both surgical techniques and postoperative and long-term medical treatment, the biliary complications are still considered a relatively high risk for LDLT. The aim of this retrospective study was to analyze the incidence of biliary complications and identify predisposing risk factors. The clinical and follow-up data of 175 adult patients receiving LDLT (right lobe or left lobe) between 2002 and December 2008 were collected and retrospectively analyzed. Patients were divided into 2 groups: with biliary complications (n=30) and without biliary complications (n=145). Thirty patients (17.1%) had post-transplantation biliary complications. Eight patients (4.6%) were diagnosed with bile leakage, while 24 patients (13.7%) developed biliary stricture. Percentage of steatosis of the graft and hepatic artery thrombosis after LDLT were two factors upon univariate analysis (p=0.034, p=0.01, respectively). In multivariate logistic analysis, 20-50% macrovesicular steatosis emerged as a new defined risk factor by us (p=0.001). There was no difference in patient survival rate in different groups and sorts of graft steatosis (p>0.05). We consider that using a graft with macro-vesicular steatosis in 20-50% should be put on the table carefully, balancing both sides of positive and negative.

  11. Unmanipulated haploidentical bone marrow transplantation and post-transplant cyclophosphamide for hematologic malignanices following a myeloablative conditioning: an update.

    Science.gov (United States)

    Bacigalupo, A; Dominietto, A; Ghiso, A; Di Grazia, C; Lamparelli, T; Gualandi, F; Bregante, S; Van Lint, M T; Geroldi, S; Luchetti, S; Grasso, R; Pozzi, S; Colombo, N; Tedone, E; Varaldo, R; Raiola, A M

    2015-06-01

    This is a report of 148 patients with hematologic malignancies who received an unmanipulated haploidentical bone marrow transplant (BMT), followed by post-transplant high-dose cyclophosphamide (PT-CY). All patients received a myeloablative conditioning consisting of thiotepa, busulfan, fludarabine (n=92) or TBI, fludarabine (n=56). The median age was 47 years (17-74); 47 patients were in first remission (CR1), 37 in second remission (CR2) and 64 had an active disease; all patients were first grafts. The diagnosis was acute leukemia (n=75), myelodisplastic syndrome (n=24), myelofibrosis (n=16), high-grade lymphoma (n=15) and others (n=18). GVHD prophylaxis consisted in PT-CY on days +3 and +5, cyclosporine (from day 0), and mycophenolate (from day +1). The median day for neutrophil engraftment was day +18 (13-32). The cumulative incidence of grades II-IV acute GVHD was 24%, and of grades III-IV GVHD 10%. The incidence of moderate-severe chronic GVHD was 12%. With a median follow-up for the surviving patients of 313 days (100-1162), the cumulative incidence of transplant-related mortality (TRM) is 13%, and the relapse-related death is 23%. The actuarial 22 months overall survival is 77% for CR1 patients, 49% for CR2 patients and 38% for patients grafted in relapse (Ptransplant.

  12. Retroviral vector integration in post-transplant hematopoiesis in mice conditioned with either submyeloablative or ablative irradiation.

    Science.gov (United States)

    Sadat, M A; Dirscherl, S; Sastry, L; Dantzer, J; Pech, N; Griffin, S; Hawkins, T; Zhao, Y; Barese, C N; Cross, S; Orazi, A; An, C; Goebel, W S; Yoder, M C; Li, X; Grez, M; Cornetta, K; Mooney, S D; Dinauer, M C

    2009-12-01

    X-linked chronic granulomatous disease (X-CGD) is an inherited immunodeficiency with absent phagocyte NADPH-oxidase activity caused by defects in the gene-encoding gp91(phox). Here, we evaluated strategies for less intensive conditioning for gene therapy of genetic blood disorders without selective advantage for gene correction, such as might be used in a human X-CGD protocol. We compared submyeloablative with ablative irradiation as conditioning in murine X-CGD, examining engraftment, oxidase activity and vector integration in mice transplanted with marrow transduced with a gamma-retroviral vector for gp91(phox) expression. The frequency of oxidase-positive neutrophils in the donor population was unexpectedly higher in many 300 cGy-conditioned mice compared with lethally irradiated recipients, as was the fraction of vector-marked donor secondary CFU-S12. Vector integration sites in marrow, spleen and secondary CFU-S12 DNA from primary recipients were enriched for cancer-associated genes, including Evi1, and integrations in or near cancer-associated genes were more frequent in marrow and secondary CFU-S12 from 300 cGy-conditioned mice compared with fully ablated mice. These findings support the concept that vector integration can confer a selection bias, and suggest that the intensity of the conditioning regimen may further influence the effects of vector integration on clonal selection in post-transplant engraftment and hematopoiesis.

  13. A new data-driven model for post-transplant antibody dynamics in high risk kidney transplantation.

    Science.gov (United States)

    Zhang, Yan; Briggs, David; Lowe, David; Mitchell, Daniel; Daga, Sunil; Krishnan, Nithya; Higgins, Robert; Khovanova, Natasha

    2017-02-01

    The dynamics of donor specific human leukocyte antigen antibodies during early stage after kidney transplantation are of great clinical interest as these antibodies are considered to be associated with short and long term clinical outcomes. The limited number of antibody time series and their diverse patterns have made the task of modelling difficult. Focusing on one typical post-transplant dynamic pattern with rapid falls and stable settling levels, a novel data-driven model has been developed for the first time. A variational Bayesian inference method has been applied to select the best model and learn its parameters for 39 time series from two groups of graft recipients, i.e. patients with and without acute antibody-mediated rejection (AMR) episodes. Linear and nonlinear dynamic models of different order were attempted to fit the time series, and the third order linear model provided the best description of the common features in both groups. Both deterministic and stochastic parameters are found to be significantly different in the AMR and no-AMR groups showing that the time series in the AMR group have significantly higher frequency of oscillations and faster dissipation rates. This research may potentially lead to better understanding of the immunological mechanisms involved in kidney transplantation.

  14. Therapeutic drug monitoring for either oral or intravenous busulfan when combined with pre- and post-transplantation cyclophosphamide.

    Science.gov (United States)

    Lombardi, Lindsey R; Kanakry, Christopher G; Zahurak, Marianna; Durakovic, Nadira; Bolaños-Meade, Javier; Kasamon, Yvette L; Gladstone, Douglas E; Matsui, William; Borrello, Ivan; Huff, Carol Ann; Swinnen, Lode J; Brodsky, Robert A; Ambinder, Richard F; Fuchs, Ephraim J; Rosner, Gary L; Jones, Richard J; Luznik, Leo

    2016-01-01

    Busulfan (Bu)/cyclophosphamide (Cy) is a standard conditioning platform for allogeneic transplantation. We developed a strategy separating the Cy into two pre/post-transplantation doses (PTCy), providing myeloablative conditioning and single-agent graft-versus-host disease (GVHD) prophylaxis. We investigated the impact of Bu route on treatment-related toxicity for 131 consecutive adult patients. Busulfan was administered in four daily divided doses either orally (n = 72) or intravenously (n = 59) with pharmacokinetics on the first-dose and as necessary on subsequent doses to achieve a target area-under-the-concentration-curve (AUC) of 800-1400 μmol*min/L per dose. BuCy/PTCy with pharmacokinetics is well-tolerated with low treatment-related toxicity. Hepatic veno-occlusive disease incidence was 6% with two fatal events. Bu administration route in the context of BuCy/PTCy did not statistically impact hepatotoxicity, GVHD, relapse, disease-free survival, or overall survival. The BuCy/PTCy platform has a low incidence of treatment-related toxicity, including hepatotoxicity, in hematologic malignancies when using pharmacokinetics for a target AUC of 800-1400 μmol*min/L, irrespective of Bu administration route.

  15. Dual pathology as a cause of proteinuria in the post-transplant period; report of a case

    Directory of Open Access Journals (Sweden)

    Tewari Rohit

    2016-01-01

    Full Text Available Proteinuria is common after renal transplantation and affects between 35%-45% of patients during the same year as their transplant. We report a case of dual pathology in the renal allograft as a cause of severe proteinuria. A 38-year-old male presented with end-stage renal disease. He underwent live related renal allograft transplant. His immediate post-transplant period was unremarkable. He developed rise in serum creatinine (2.1 mg/dl 6 months after transplant and was biopsied. He was diagnosed as a case of acute cellular rejection type Ib with suspicion for antibody mediated rejection. He was treated with methylprednisolone to which he showed a good response with return of serum creatinine to 1.6 mg/dl. Subsequently, he developed a nephrotic range proteinuria 6 months after this episode of rejection. Repeat biopsy was performed. He was diagnosed as a case of immune complex mediated glomerulonephritis (GN (morphologically consistent with pattern of membranoproliferative glomerulonephritis with chronic humoral rejection in the form of transplant glomerulopathy (TG. IHC for C4d and immunofluorescence studies were instrumental making the diagnosis. He was treated with steroids and rituximab to which he showed a good response with remission of proteinuria. This case highlights the importance of picking up dual pathology in an allograft biopsy to ensure appropriate therapy. The role of C4d and its correct interpretation is further highlighted, especially with regard to pattern (granular versus linear and location (glomerular capillaries versus peritubular capillaries.

  16. Methotrexate-related Epstein-Barr Virus (EBV)-associated lymphoproliferative disorder--so-called "Hodgkin-like lesion"--of the oral cavity in a patient with rheumatoid arthritis.

    Science.gov (United States)

    Kikuchi, Kentaro; Miyazaki, Yuji; Tanaka, Akio; Shigematu, Hisao; Kojima, Masaru; Sakashita, Hideaki; Kusama, Kaoru

    2010-12-01

    Patients affected by autoimmune diseases (rheumatoid arthritis, psoriasis, dermatomyositis) who are treated with methotrexate (MTX) sometimes develop lymphoproliferative disorders (LPDs). In approximately 40% of reported cases, the affected sites have been extranodal, and have included the gastrointestinal tract, skin, lung, kidney, and soft tissues. However, MTX-associated LPD (MTX-LPD) is extremely rare in the oral cavity. Here we report a 69-year-old Japanese woman with rheumatoid arthritis (RA) who developed MTX-LPD resembling Hodgkin's disease--so-called "Hodgkin-like lesion"--in the left upper jaw. Histopathologically, large atypical lymphoid cells including Hodgkin or Reed-Sternberg-like cells were found to have infiltrated into granulation tissue in the ulcerative oral mucosa. Immunohistochemistry showed that the large atypical cells were positive for CD20, CD30 and Epstein-Barr virus (EBV)-latent infection membrane protein-1 (LMP-1) and negative for CD15. EBV was detected by in situ hybridization (ISH) with EBV-encoded small RNA (EBER), and polymerase chain reaction (PCR) for LMP-1 and EBNA-2 in material taken from the formalin-fixed, paraffin-embedded specimen. To our knowledge, this is the first reported case of MTX-related EBV-associated LPD (MTX-EBVLPD), "Hodgkin-like lesion", of the oral cavity in a patient with RA.

  17. 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.

  18. Histopathological analysis of pre-implantation donor kidney biopsies: association with graft survival and function in one year post-transplantation

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    Karla Lais Pêgas

    2014-04-01

    Full Text Available Introduction: Pre-implantation kidney biopsy is a decision-making tool when considering the use of grafts from deceased donors with expanded criteria, implanting one or two kidneys and comparing this to post-transplantation biopsies. The role of histopathological alterations in kidney compartments as a prognostic factor in graft survival and function has had conflicting results. Objective: This study evaluated the prevalence of chronic alterations in pre-implant biopsies of kidney grafts and the association of findings with graft function and survival in one year post-transplant. Methods: 110 biopsies were analyzed between 2006 and 2009 at Santa Casa de Porto Alegre, including live donors, ideal deceased donors and those with expanded criteria. The score was computed according to criteria suggested by Remuzzi. The glomerular filtration rate (GFR was calculated using the abbreviated MDRD formula. Results: No statistical difference was found in the survival of donors stratified according to Remuzzi criteria. The GFR was significantly associated with the total scores in the groups with mild and moderate alterations, and in the kidney compartments alone, by univariate analysis. The multivariate model found an association with the presence of arteriosclerosis, glomerulosclerosis, acute rejection and delayed graft function. Conclusion: Pre-transplant chronic kidney alterations did not influence the post-transplantation one-year graft survival, but arteriosclerosis and glomerulosclerosis is predictive of a worse GFR. Delayed graft function and acute rejection are independent prognostic factors.

  19. A meta-analysis of potential relationship between Epstein-Barr-Encoded-RNA (EBER and onset time of post-transplant lymphoproliferative disorders

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    Hossein Khedmat

    2015-01-01

    Full Text Available Epstein-Barr virus (EBV encodes two non-polyadenylated RNAs termed EBV-encoded RNAs (EBERs. In this study, we tried to find series in which data of EBER and onset time of post-transplant lymphoproliferative disorder (PTLD for patients have been documented to conduct a meta-analysis. A comprehensive search of the literature was performed by Pubmed and Google scholar to find reports indicating test results for EBER and PTLD onset in transplant patients. PTLD was considered "early onset" when it develops within the first post-transplant year. Finally, 265 patients from 15 studies have been included in the meta-analysis. The overall meta-analysis also showed a significant relation between EBER test positivity and early-onset PTLD development [relative risk (RR: 1.36; 95% CI: 1.16-1.59; P <0.001]. The i2 index was 49.8%. Our study suggests that PTLD lesions with positive EBER test are more likely to develop within the early post-transplant period. Since early-onset PTLD is supposed to have better prognosis, having a positive EBER test might not be a bad news. However, for having a precise conclusion, prospective studies are needed to be conducted.

  20. Human peripheral blood B-Cell compartments: A crossroad in B-cell traffic

    NARCIS (Netherlands)

    M. Perez-Andres; B. Paiva; W.G. Nieto (Wendy); A. Caraux; A. Schmitz; J. Almeida (Julia); R.F. Vogt; G.E. Marti; A.C. Rawstron; M.C. van Zelm (Menno); J.J.M. van Dongen (Jacques); H.E. Johnsen (Hans); B. Klein (Binie); A. Orfao (Alberto)

    2010-01-01

    textabstractA relatively high number of different subsets of B-cells are generated through the differentiation of early B-cell precursors into mature B-lymphocytes in the bone marrow (BM) and antigen-triggered maturation of germinal center B-cells into memory B-lymphocytes and plasmablasts in lympho

  1. Human Peripheral Blood B-Cell Compartments : A Crossroad in B-Cell Traffic

    NARCIS (Netherlands)

    Perez-Andres, M.; Paiva, B.; Nieto, W. G.; Caraux, A.; Schmitz, A.; Almeida, J.; Vogt, R. F.; Marti, G. E.; Rawstron, A. C.; Van Zelm, M. C.; Van Dongen, J. J. M.; Johnsen, H. E.; Klein, B.; Orfao, A.

    2010-01-01

    A relatively high number of different subsets of B-cells are generated through the differentiation of early B-cell precursors into mature B-lymphocytes in the bone marrow (BM) and antigen-triggered maturation of germinal center B-cells into memory B-lymphocytes and plasmablasts in lymphoid tissues.

  2. Human Peripheral Blood B-Cell Compartments : A Crossroad in B-Cell Traffic

    NARCIS (Netherlands)

    Perez-Andres, M.; Paiva, B.; Nieto, W. G.; Caraux, A.; Schmitz, A.; Almeida, J.; Vogt, R. F.; Marti, G. E.; Rawstron, A. C.; Van Zelm, M. C.; Van Dongen, J. J. M.; Johnsen, H. E.; Klein, B.; Orfao, A.

    2010-01-01

    A relatively high number of different subsets of B-cells are generated through the differentiation of early B-cell precursors into mature B-lymphocytes in the bone marrow (BM) and antigen-triggered maturation of germinal center B-cells into memory B-lymphocytes and plasmablasts in lymphoid tissues.

  3. Phagocytic activity of monocytes, their subpopulations and granulocytes during post-transplant adverse events after hematopoietic stem cell transplantation.

    Science.gov (United States)

    Döring, Michaela; Cabanillas Stanchi, Karin Melanie; Erbacher, Annika; Haufe, Susanne; Schwarze, Carl Philipp; Handgretinger, Rupert; Hofbeck, Michael; Kerst, Gunter

    2015-05-01

    Phagocytosis of granulocytes and monocytes presents a major mechanism that contributes to the clearance of pathogens and cell debris. We analyzed the phagocytic activity of the peripheral blood cell monocytes, three monocyte subpopulations and granulocytes before and up to one year after hematopoietic stem cell transplantation, as well as during transplant-related adverse events. 25 pediatric patients and young adults (median age of 11.0 years) with hemato-oncological malignancies and non malignancies were enrolled in the prospective study. Ingestion of fluorescence-labeled Escherichia coli bacteria was used to assess the phagocytic activity of monocytes and their subpopulations and granulocytes by means of flow cytometry in the patient group as well as in a control group (n=36). During sepsis, a significant increase of phagocytic activity of monocytes (P=0.0003) and a significant decrease of the phagocytic activity of granulocytes (P=0.0003) and the CD14+ CD16++ monocyte subpopulation (P=0.0020) occurred. At the onset of a veno-occlusive disease, a significant increase of phagocytic activity in the CD14++ CD16+ monocyte subpopulation (P=0.001) and a significant decrease in the phagocytic activity of the CD14++ CD16- monocyte subpopulation (P=0.0048) were observed. In conclusion, the phagocytic activity of monocytes, their subpopulations and granulocytes might be a useful and easy determinable parameter that enables identification of post-transplant complications after hematopoietic stem cell transplantation. The alterations of phagocytic activity contribute to the altered immune response that accompanies adverse events after hematopoietic stem cell transplantation.

  4. Post-transplantation lymphoproliferative disorders (PTLD localized in the central nervous system: Report from an international survey on PTLD

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    Hossein Khedmat

    2013-01-01

    Full Text Available Post-transplantation lymphoproliferative disorders (PTLD localized to the central nervous system (CNS is a rare but potentially fatal side-effect of immunosuppression for organ transplantation. Till now, to the best of our knowledge, the total number of such cases reported worldwide is less than 100. In this survey, we collected the data of PTLD localized to the CNS (CNS-PTLD and compared this data with other PTLD patients with localizations to other areas serving as the control group. A comprehensive search was performed for studies reporting CNS-PTLD data in the Pubmed and Google scholar search engines. Finally, international data from 21 different studies were included in the analysis. Overall, 367 patients were entered into analysis. Organ recipients with CNS-PTLD had comparable gender make up, lymphoma cell types, Epstein-Barr virus infection rate, remission and mortality rates, with PTLD patients having other localizations. Multiorgan involvement as well as disseminated lymphoma were significantly more prevalent in the control group (P <0.05. At the last follow-up, 192 (60% patients were dead (47 missing data. Irrespective of whether the overall death or only death due to PTLD was used as the final outcome, we found that the survival rates were similar for patients of the two groups (P = 0.895. Renal transplant recipients are at greater risk for developing CNS involvement by PTLD, while heart and liver recipients represent significant lower risks for the same. This study showed that PTLD patients who had CNS presentation have quite a comparable outcome compared with those with other areas of localization. However, further prospective studies are needed for reaffirming our findings.

  5. Proteome and Computational Analyses Reveal New Insights into the Mechanisms of Hepatitis C Virus Mediated Liver Disease Post-Transplantation

    Science.gov (United States)

    Diamond, Deborah L.; Krasnoselsky, Alexei L.; Burnum, Kristin E.; Monroe, Matthew E.; Webb-Robertson, Bobbie-Jo; McDermott, Jason E.; Yeh, Matthew M.; Dzib, Jose Felipe Golib; Susnow, Nathan; Strom, Susan; Proll, Sean C.; Belisle, Sarah E.; Purdy, David E.; Rasmussen, Angela L.; Walters, Kathie-Anne; Jacobs, Jon M.; Gritsenko, Marina A.; Camp, David G.; Bhattacharya, Renuka; Perkins, James D.; Carithers, Robert L.; Liou, Iris W.; Larson, Anne M.; Benecke, Arndt; Waters, Katrina M.; Smith, Richard D.; Katze, Michael G.

    2012-01-01

    Liver transplant tissues offer the unique opportunity to model the longitudinal protein abundance changes occurring during hepatitis C virus (HCV)-associated liver disease progression in vivo. In this study, our goal was to identify molecular signatures, and potential key regulatory proteins, representative of the processes influencing early progression to fibrosis. We performed global protein profiling analyses on 24 liver biopsy specimens obtained from 15 HCV+ liver transplant recipients at 6 and/or 12 months post-transplantation. Differentially regulated proteins associated with early progression to fibrosis were identified by analysis of the area under the receiver operating characteristic curve (AUC). Analysis of serum metabolites was performed on samples obtained from an independent cohort of 60 HCV+ liver transplant patients. Computational modeling approaches were applied to identify potential key regulatory proteins of liver fibrogenesis. Among 4,324 proteins identified, 250 exhibited significant differential regulation in patients with rapidly progressive fibrosis. Patients with rapid fibrosis progression exhibited enrichment in differentially regulated proteins associated with various immune, hepatoprotective, and fibrogenic processes. The observed increase in pro-inflammatory activity and impairment in anti-oxidant defenses suggests that patients who develop significant liver injury experience elevated oxidative stresses. This was supported by an independent study demonstrating the altered abundance of oxidative stress associated serum metabolites in patients who develop severe liver injury. Computational modeling approaches further highlight a potentially important link between HCV-associated oxidative stress and epigenetic regulatory mechanisms impacting on liver fibrogenesis. In conclusion, our proteome and metabolome analyses provide new insights into the role for increased oxidative stress in the rapid fibrosis progression observed in HCV+ liver

  6. Histological and clinical findings in patients with post-transplantation and classical encapsulating peritoneal sclerosis: a European multicenter study.

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    Joerg Latus

    Full Text Available Encapsulating peritoneal sclerosis (EPS commonly presents after peritoneal dialysis has been stopped, either post-transplantation (PT-EPS or after switching to hemodialysis (classical EPS, cEPS. The aim of the present study was to investigate whether PT-EPS and cEPS differ in morphology and clinical course.In this European multicenter study we included fifty-six EPS patients, retrospectively paired-matched for peritoneal dialysis (PD duration. Twenty-eight patients developed EPS after renal transplantation, whereas the other twenty-eight patients were classical EPS patients. Demographic data, PD details, and course of disease were documented. Peritoneal biopsies of all patients were investigated using histological criteria.Eighteen patients from the Netherlands and thirty-eight patients from Germany were included. Time on PD was 78(64-95 in the PT-EPS and 72(50-89 months in the cEPS group (p>0.05. There were no significant differences between the morphological findings of cEPS and PT-EPS. Podoplanin positive cells were a prominent feature in both groups, but with a similar distribution of the podoplanin patterns. Time between cessation of PD to the clinical diagnosis of EPS was significantly shorter in the PT-EPS group as compared to cEPS (4(2-9 months versus 23(7-24 months, p<0.001. Peritonitis rate was significantly higher in cEPS.In peritoneal biopsies PT-EPS and cEPS are not distinguishable by histomorphology and immunohistochemistry, which argues against different entities. The critical phase for PT-EPS is during the first year after transplantation and therefore earlier after PD cessation then in cEPS.

  7. Drug-drug interactions between immunosuppressants and antidiabetic drugs in the treatment of post-transplant diabetes mellitus.

    Science.gov (United States)

    Vanhove, Thomas; Remijsen, Quinten; Kuypers, Dirk; Gillard, Pieter

    2016-09-14

    Post-transplant diabetes mellitus is a frequent complication of solid organ transplantation that generally requires treatment with lifestyle interventions and antidiabetic medication. A number of demonstrated and potential pharmacokinetic drug-drug interactions (DDIs) exist between commonly used immunosuppressants and antidiabetic drugs, which are comprehensively summarized in this review. Cyclosporine (CsA) itself inhibits the cytochrome P450 (CYP) 3A4 enzyme and a variety of drug transporters. As a result, it increases exposure to repaglinide and sitagliptin, will likely increase the exposure to nateglinide, glyburide, saxagliptin, vildagliptin and alogliptin, and could theoretically increase the exposure to gliquidone and several sodium-glucose transporter (SGLT)-2 inhibitors. Currently available data, although limited, suggest that these increases are modest and, particularly with regard to gliptins and SGLT-2 inhibitors, unlikely to result in hypoglycemia. The interaction with repaglinide is more pronounced but does not preclude concomitant use if repaglinide dose is gradually titrated. Mycophenolate mofetil and azathioprine do not engage in DDIs with any antidiabetic drug. Although calcineurin inhibitors (CNIs) and mammalian target of rapamycin inhibitors (mTORi) are intrinsically prone to DDIs, their disposition is not influenced by metformin, pioglitazone, sulfonylureas (except possibly glyburide) or insulin. An effect of gliptins on the disposition of CNIs and mTORi is unlikely, but has not been definitively ruled out. Based on their disposition profiles, glyburide and canagliflozin could affect CNI and mTORi disposition although this requires further study. Finally, delayed gastric emptying as a result of glucagon-like peptide-1 agonists seems to have a limited, but not necessarily negligible effect on CNI disposition.

  8. Preliminary experience on the use of PET/CT in the management of pediatric post-transplant lymphoproliferative disorder.

    Science.gov (United States)

    Guerra-García, Pilar; Hirsch, Steffen; Levine, Daniel S; Taj, Mary M

    2017-06-14

    Post-transplant lymphoproliferative disorder (PTLD) is a well-known complication following prolonged immunosuppression. Contrary to other lymphomas, there is no standardized imaging approach to assess PTLD either at staging or for response to therapy. Positron emission tomography/computed tomography (PET/CT) is an imaging modality that has proven to be useful in lymphoma. However, there is still limited data concerning its use in pediatric PTLD. Our study evaluates the use of PET/CT in pediatric PTLD at our institution. To assess the role of PET/CT in pediatric PTLD, we reviewed the pediatric patients with PTLD who had undergone PET/CT at our institution between 2000 and 2016. Nine patients were identified. Six had PET/CT at diagnosis. All lesions seen on CT were identified with PET/CT. Fourteen PET/CTs were done during treatment. Eight PET/CTs were negative, including three where CT showed areas of uncertain significance. In these cases, PET/CT helped us to stop treatment and the patients remain in remission after a long follow-up (mean 74.3 months; range 12.4-180.9 months). PET/CT revealed additional disease in two cases, therefore treatment was intensified. Six biopsies and close follow-up was done to confirm PET/CT results. In one case, PET/CT did not identify central nervous system involvement demonstrated on magnetic resonance imaging. PET/CT may have an important role in the staging and follow-up of pediatric PTLD. In our cohort, PET/CT was helpful in staging and assessing treatment response and in clarifying equivocal findings on other imaging modalities. © 2017 Wiley Periodicals, Inc.

  9. B Cell Tolerance in Health and Disease

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    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.

  10. B Cells and Autoantibodies in Multiple Sclerosis

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    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.

  11. The early history of B cells.

    Science.gov (United States)

    Cooper, Max D

    2015-03-01

    The separate development of functionally intertwined lineages of lymphocytes known as B cells and T cells is now recognized as a fundamental organizing principle of the adaptive immune system in all vertebrates. Immunologists strive to define the different sublineages of the clonally diverse B cells and T cells, how they interact with each other and how they interact with innate lymphoid cells and other elements of the innate immune system to counter infections, cancer and the development of autoimmune and inflammatory diseases. On the 50th anniversary of the recognition of B cells as a discrete cell lineage, this Timeline article recounts some of the milestones marking the development of the concept that B cells are a functionally and developmentally distinct arm of the adaptive immune system.

  12. B Cell Epitope-Based Vaccination Therapy

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    Yoshie Kametani

    2015-08-01

    Full Text Available Currently, many peptide vaccines are undergoing clinical studies. Most of these vaccines were developed to activate cytotoxic T cells; however, the response is not robust. Unlike vaccines, anti-cancer antibodies based on passive immunity have been approved as a standard treatment. Since passive immunity is more effective in tumor treatment, the evidence suggests that limited B cell epitope-based peptide vaccines may have similar activity. Nevertheless, such peptide vaccines have not been intensively developed primarily because humoral immunity is thought to be preferable to cancer progression. B cells secrete cytokines, which suppress immune functions. This review discusses the possibility of therapeutic antibody induction by a peptide vaccine and the role of active and passive B cell immunity in cancer patients. We also discuss the use of humanized mice as a pre-clinical model. The necessity of a better understanding of the activity of B cells in cancer is also discussed.

  13. MYSM1-dependent checkpoints in B cell lineage differentiation and B cell-mediated immune response.

    Science.gov (United States)

    Förster, Michael; Farrington, Kyo; Petrov, Jessica C; Belle, Jad I; Mindt, Barbara C; Witalis, Mariko; Duerr, Claudia U; Fritz, Jörg H; Nijnik, Anastasia

    2017-03-01

    MYSM1 is a chromatin-binding histone deubiquitinase. MYSM1 mutations in humans result in lymphopenia whereas loss of Mysm1 in mice causes severe hematopoietic abnormalities, including an early arrest in B cell development. However, it remains unknown whether MYSM1 is required at later checkpoints in B cell development or for B cell-mediated immune responses. We analyzed conditional mouse models Mysm1(fl/fl)Tg.mb1-cre, Mysm1(fl/fl)Tg.CD19-cre, and Mysm1(fl/fl)Tg.CD21-cre with inactivation of Mysm1 at prepro-B, pre-B, and follicular B cell stages of development. We show that loss of Mysm1 at the prepro-B cell stage in Mysm1(fl/fl)Tg.mb1-cre mice results in impaired B cell differentiation, with an ∼2-fold reduction in B cell numbers in the lymphoid organs. Mysm1(fl/fl)Tg.mb1-cre B cells also showed increased expression of activation markers and impaired survival and proliferation. In contrast, Mysm1 was largely dispensable from the pre-B cell stage onward, with Mysm1(fl/fl)Tg.CD19-cre and Mysm1(fl/fl)Tg.CD21-cre mice showing no alterations in B cell numbers and largely normal responses to stimulation. MYSM1, therefore, has an essential role in B cell lineage specification but is dispensable at later stages of development. Importantly, MYSM1 activity at the prepro-B cell stage of development is important for the normal programming of B cell responses to stimulation once they complete their maturation process.

  14. Genome-wide analysis of immune activation in human T and B cells reveals distinct classes of alternatively spliced genes.

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    Yevgeniy A Grigoryev

    Full Text Available Alternative splicing of pre-mRNA is a mechanism that increases the protein diversity of a single gene by differential exon inclusion/exclusion during post-transcriptional processing. While alternative splicing is established to occur during lymphocyte activation, little is known about the role it plays during the immune response. Our study is among the first reports of a systematic genome-wide analysis of activated human T and B lymphocytes using whole exon DNA microarrays integrating alternative splicing and differential gene expression. Purified human CD2(+ T or CD19(+ B cells were activated using protocols to model the early events in post-transplant allograft immunity and sampled as a function of time during the process of immune activation. Here we show that 3 distinct classes of alternatively spliced and/or differentially expressed genes change in an ordered manner as a function of immune activation. We mapped our results to function-based canonical pathways and demonstrated that some are populated by only one class of genes, like integrin signaling, while other pathways, such as purine metabolism and T cell receptor signaling, are populated by all three classes of genes. Our studies augment the current view of T and B cell activation in immunity that has been based exclusively upon differential gene expression by providing evidence for a large number of molecular networks populated as a function of time and activation by alternatively spliced genes, many of which are constitutively expressed.

  15. Regulation of B Cell to Plasma Cell Transition within the Follicular B Cell Response.

    Science.gov (United States)

    Nera, K-P; Kyläniemi, M K; Lassila, O

    2015-09-01

    Persistent humoral immunity depends on the follicular B cell response and on the generation of somatically mutated high-affinity plasma cells and memory B cells. Upon activation by an antigen, cognately activated follicular B cells and follicular T helper (TFH ) cells initiate germinal centre (GC) reaction during which high-affinity effector cells are generated. The differentiation of activated follicular B cells into plasma cells and memory B cells is guided by complex selection events, both at the cellular and molecular level. The transition of B cell into a plasma cell during the GC response involves alterations in the microenvironment and developmental state of the cell, which are guided by cell-extrinsic signals. The developmental cell fate decisions in response to these signals are coordinated by cell-intrinsic gene regulatory network functioning at epigenetic, transcriptional and post-transcriptional levels.

  16. VITA-D: Cholecalciferol substitution in vitamin D deficient kidney transplant recipients: A randomized, placebo-controlled study to evaluate the post-transplant outcome

    Directory of Open Access Journals (Sweden)

    Thiem Ursula

    2009-05-01

    Full Text Available Abstract Background Vitamin D does not only regulate calcium homeostasis but also plays an important role as an immune modulator. It influences the immune system through the induction of immune shifts and regulatory cells resulting in immunologic tolerance. As such, vitamin D is thought to exert beneficial effects within the transplant setting, especially in kidney transplant recipients, considering the high prevalence of vitamin D deficiency in kidney transplant recipients. Methods/Design The VITA-D study, a randomized, placebo-controlled, double-blind study with two parallel groups including a total of 200 kidney transplant recipients, is designed to investigate the immunomodulatory and renoprotective effects of cholecalciferol (vitamin D3 within the transplant setting. Kidney transplant recipients found to have vitamin D deficiency defined as 25-hydroxyvitamin D3 The objective is to evaluate the influence of vitamin D3 substitution in vitamin D deficient kidney transplant recipients on the post-transplant outcome. As a primary endpoint glomerular filtration rate calculated with the MDRD formula (modification of diet in renal disease one year after kidney transplantation will be evaluated. Incidence of acute rejection episodes, and the number and severity of infections (analyzed by means of C-reactive protein within the first year after transplantation will be monitored as well. As a secondary endpoint the influence of vitamin D3 on bone mineral density within the first year post-transplant will be assessed. Three DXA analyses will be performed, one within the first four weeks post-transplant, one five months and one twelve months after kidney transplantation. Trial Registration ClinicalTrials.gov NCT00752401

  17. B-cell-independent lymphoid tissue infection by a B-cell-tropic rhadinovirus.

    Science.gov (United States)

    Chao, Brittany; Frederico, Bruno; Stevenson, Philip G

    2015-09-01

    Lymphocytes provide gammaherpesviruses with a self-renewing substrate for persistent infection and with transport to mucosal sites for host exit. Their role in the initial colonization of new hosts is less clear. Murid herpesvirus 4 (MuHV-4), an experimentally accessible, B-cell-tropic rhadinovirus (gamma-2 herpesvirus), persistently infects both immunocompetent and B-cell-deficient mice. A lack of B-cells did not compromise MuHV-4 entry into lymphoid tissue, which involved myeloid cell infection. However, it impaired infection amplification and MuHV-4 exit from lymphoid tissue, which involved myeloid to B-cell transfer.

  18. Persistent Polyclonal B Cell Lymphocytosis B Cells Can Be Activated through CD40-CD154 Interaction

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    Emmanuelle Dugas-Bourdages

    2014-01-01

    Full Text Available Persistent polyclonal B cell lymphocytosis (PPBL is a rare disorder, diagnosed primarily in adult female smokers and characterized by an expansion of CD19+CD27+IgM+ memory B cells, by the presence of binucleated lymphocytes, and by a moderate elevation of serum IgM. The clinical course is usually benign, but it is not known whether or not PPBL might be part of a process leading to the emergence of a malignant proliferative disorder. In this study we sought to investigate the functional response of B cells from patients with PPBL by use of an optimal memory B cell culture model based on the CD40-CD154 interaction. We found that the proliferation of PPBL B cells was almost as important as that of B cells from normal controls, resulting in high immunoglobulin secretion with in vitro isotypic switching. We conclude that the CD40-CD154 activation pathway is functional in the memory B cell population of PPBL patients, suggesting that the disorder may be due to either a dysfunction of other cells in the microenvironment or a possible defect in another B cell activation pathway.

  19. Eosinophilic density in graft biopsies positive for rejection and blood eosinophil count can predict development of post-transplant digestive tract eosinophilia.

    Science.gov (United States)

    Bush, Jonathan W; Mohammad, Saeed; Melin-Aldana, Hector; Kagalwalla, Amir F; Arva, Nicoleta C

    2016-06-01

    EGID is a known post-transplant complication. Its etiology has been related to antirejection medication, but other factors may also play a role as only few transplant recipients develop EGID despite standardized treatment. This study aimed to determine whether EGID is associated with rejection events and with a specific phenotype of the rejection-positive graft biopsies in children with solid organ transplant. All patients with liver, heart, and kidney transplant followed at our institution were included in the study. Digestive tract eosinophilia was more common in heart and liver recipients and was a rare event after renal transplantation. Subjects with EGID had higher incidence of rejection and elevated peripheral blood AEC. The first rejection event and high AEC values preceded EGID diagnosis in the majority of patients. Histologically, the initial rejection-positive graft biopsy revealed accentuated eosinophilia in EGID patients compared with non-EGID cohort, which correlated with higher blood eosinophil counts at the time of first rejection episode. Prominent graft tissue and peripheral blood eosinophilia prior to EGID diagnosis suggests a predisposition for eosinophil activation in patients with post-transplant digestive eosinophilic disorder. These parameters can be used as markers for subsequent development of EGID. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Lower relapse rates with good post-transplant outcome in alcoholic liver disease: Experience from a living donor liver transplant center.

    Science.gov (United States)

    Saigal, Sanjiv; Choudhary, Narendra Singh; Yadav, Sanjay Kumar; Saraf, Neeraj; Kumar, Naveen; Rai, Rahul; Mehrotra, Saurabh; Rastogi, Vipul; Rastogi, Amit; Goja, Sanjay; Bhangui, Prashant; Ramachandra, Sumana K; Raut, Vikram; Gautam, Dheeraj; Soin, Arvinder Singh

    2016-03-01

    Post-transplant relapse is a major factor influencing the long-term outcome in alcoholic liver disease (ALD) patients. The aim of this study was to evaluate the relapse rates following living donor liver transplantation (LDLT) in patients with ALD in the Indian context with strong family support. Of 458 patients who underwent LDLT for ALD, 408 were included in the study. Post-transplant relapse was determined by information provided by the patient and/or family by means of outpatient and e-mail questionnaire, supported by clinical/biochemical parameters/liver histopathology. All except one were males, with a mean age of 46.9 ± 8.5 years. The overall rate of relapse was 9.5 % at 34.7 months (interquartile range (IQR) 15-57.6), lower than that reported in the literature from the West. The relapse rate was higher in patients with a shorter duration of pre-transplant abstinence (17.4 % and 15.4 % for recipients with pre-transplant abstinence of Good results can be obtained following LDLT for ALD, with significantly lower relapse rates in our setup as compared to the West.

  1. Blood dendritic cell levels associated with impaired IL-12 production and T-cell deficiency in patients with kidney disease: implications for post-transplant viral infections.

    Science.gov (United States)

    Chen, Ping; Sun, Qianmei; Huang, Yanfei; Atta, Mohamed G; Turban, Sharon; Segev, Dorry L; Marr, Kieren A; Naqvi, Fizza F; Alachkar, Nada; Kraus, Edward S; Womer, Karl L

    2014-10-01

    Reduced pretransplant blood myeloid dendritic cell (mDC) levels are associated with post-transplant BK viremia and cytomegalovirus (CMV) disease after kidney transplantation. To elucidate potential mechanisms by which mDC levels might influence these outcomes, we studied the association of mDC levels with mDC IL-12 production and T-cell level/function. Peripheral blood (PB) was studied in three groups: (i) end stage renal disease patients on hemodialysis (HD; n = 81); (ii) chronic kidney disease stage IV-V patients presenting for kidney transplant evaluation or the day of transplantation (Eval/Tx; n = 323); and (iii) healthy controls (HC; n = 22). Along with a statistically significant reduction in mDC levels, reduced CD8(+) T-cell levels were also demonstrated in the kidney disease groups compared with HC. Reduced PB mDC and monocyte-derived DC (MoDC) IL-12 production was observed after in vitro LPS stimulation in the HD versus HC groups. Finally, ELISpot assays demonstrated less robust CD3(+) INF-γ responses by MoDCs pulsed with CMV pp65 peptide from HD patients compared with HC. PB mDC level deficiency in patients with kidney disease is associated with deficient IL-12 production and T-cell level/function, which may explain the known correlation of CD8(+) T-cell lymphopenia with deficient post-transplant antiviral responses. © 2014 Steunstichting ESOT.

  2. Sirolimus for Refractory Autoimmune Hemolytic Anemia after Allogeneic Hematopoietic Stem Cell Transplantation: A Case Report and Literature Review of the Treatment of Post-Transplant Autoimmune Hemolytic Anemia.

    Science.gov (United States)

    Park, Jeong A; Lee, Hyun-Hee; Kwon, Hyun-Seop; Baik, Chung-Ryul; Song, Sae-Am; Lee, Jung Nye

    2016-01-01

    Autoimmune hemolytic anemia (AIHA) may occur after any type of allogeneic hematopoietic stem cell transplantation (HCT), even ABO-matched transplantation. It tends to be refractory to standard corticosteroid treatment and requires multiple transfusions. Though, there is no consensus regarding the optimal treatment for post-transplant severe AIHA. We present a pediatric patient with refractory AIHA after umbilical cord blood transplantation. She developed severe AIHA at 3months after transplantation and was unresponsive to multiple treatment modalities, including corticosteroids, intravenous immunoglobulin, plasma exchange and rituximab, resulting in persistent transfusion dependency. Sirolimus, a mammalian target of rapamycin inhibitor, was started on day 67 after the onset of AIHA, and this patient was successfully rescued without any complications. Sirolimus induces apoptosis in autoreactive lymphocytes, increases regulatory T cells and has been reported to have a positive effect on AIHA following solid organ transplantation (SOT). We reviewed the literature regarding post-transplant AIHA in the PubMed database and evaluated the treatment outcome of sirolimus in AIHA after SOT.

  3. B-cell responses to HIV infection.

    Science.gov (United States)

    Moir, Susan; Fauci, Anthony S

    2017-01-01

    The induction of neutralizing antibodies directed against the human immunodeficiency virus (HIV) has received considerable attention in recent years, in part driven by renewed interest and opportunities for antibody-based strategies for prevention such as passive transfer of antibodies and the development of preventive vaccines, as well as immune-based therapeutic interventions. Advances in the ability to screen, isolate, and characterize HIV-specific antibodies have led to the identification of a new generation of potent broadly neutralizing antibodies (bNAbs). The majority of these antibodies have been isolated from B cells of chronically HIV-infected individuals with detectable viremia. In this review, we provide insight into the phenotypic and functional attributes of human B cells, with a focus on HIV-specific memory B cells and plasmablasts/cells that are responsible for sustaining humoral immune responses against HIV. We discuss the abnormalities in B cells that occur in HIV infection both in the peripheral blood and lymphoid tissues, especially in the setting of persisting viremia. Finally, we consider the opportunities and drawbacks of intensively interrogating antibodies isolated from HIV-infected individuals to guide strategies aimed at developing effective antibody-based vaccine and therapeutic interventions for HIV. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  4. Plasma markers of B-cell activation and clonality in pediatric liver and hematopoietic stem cell transplant recipients

    Science.gov (United States)

    Engels, Eric A.; Savoldo, Barbara; Pfeiffer, Ruth M.; Costello, Rene; Zingone, Adriana; Heslop, Helen E.; Landgren, Ola

    2012-01-01

    Introduction Transplant recipients are at risk of post-transplant lymphoproliferative disease (PTLD). Methods: Thirty-six pediatric transplant recipients were evaluated (18 hematopoietic stem cell and 18 liver recipients; 12 had PTLD). We studied 207 longitudinal plasma samples from these recipients for three markers of B-cell activation or clonality: immunoglobulin free light chains (FLCs), soluble CD30 (sCD30), and monoclonal immunoglobulins (M-proteins). Results Kappa FLCs, lambda FLCs, and sCD30 were elevated in 20.8%, 28.0%, and 94.2% of plasma specimens, respectively. FLC and sCD30 levels increased significantly 1.18–1.82 fold per log10 Epstein Barr virus (EBV) load in peripheral blood. Five PTLD cases manifested elevated FLCs with an abnormal kappa/lambda ratio, suggesting monoclonal FLC production. M-proteins were present in 91% of PTLD cases, vs. 50–67% of other recipients with high or low EBV loads (p=0.13). Concordance of FLCs, M-proteins, and PTLD tumor light chain restriction was imperfect. For example, one PTLD case with an IgG lambda M-protein had a tumor that was kappa restricted, and another case with an M-protein had a T-cell PTLD. In an additional case, an IgM kappa M-protein and excess kappa FLCs were both detected in plasma at PTLD diagnosis; while the tumor was not restricted at diagnosis, kappa restriction was present 5 years later when the PTLD relapsed. Discussion Plasma markers of B-cell dysfunction are frequent following transplantation and associated with poor EBV control. These abnormal markers may be produced by oligoclonal B-cell populations or PTLD tumor cells, and could potentially help identify recipients at high risk of PTLD. PMID:23222884

  5. The Pre-B Cell Receptor and Its Function during B Cell Development

    Institute of Scientific and Technical Information of China (English)

    MinZhang; GopeshSrivastava; LiweiLu

    2004-01-01

    The process of B cell development in the bone marrow occurs by the stepwise rearrangements of the V, D, and J segments of the Ig H and L chain gene loci. During early B cell genesis, productive IgH chain gene rearrangement leads to assembly of the pre-B cell receptor (pre-BCR), which acts as an important checkpoint at the pro-B/preB transitional stage. The pre-BCR, transiently expressed by developing precursor B cells, comprises the Ig μH chain, surrogate light (SL) chains VpreB and λ5, as well as the signal-transducing hetero-dimer Igα/Igβ. Signaling through the pre-BCR regulates allelic exclusion at the Ig H locus, stimulates cell proliferation, and induces differentiation to small post-mitotic pre-B cells that further undergo the rearrangement of the IgL chain genes. Recent advances in elucidating the key roles of pre-BCR in B cell development have provided a better understanding of normal B lymphopoiesis and its dysregulated state leading to B cell neoplasia. Cellular & Molecular Immunology. 2004;1(2):89-94.

  6. The Pre-B Cell Receptor and Its Function during B Cell Development

    Institute of Scientific and Technical Information of China (English)

    Min Zhang; Gopesh Srivastava1; Liwei Lu

    2004-01-01

    The process of B cell development in the bone marrow occurs by the stepwise rearrangements of the V, D, and Jsegments of the Ig H and L chain gene loci. During early B cell genesis, productive IgH chain generearrangement leads to assembly of the pre-B cell receptor (pre-BCR), which acts as an important checkpointat the pro-B/preB transitional stage. The pre-BCR, transiently expressed by developing precursor B cells,comprises the Ig μH chain, surrogate light (SL) chains VpreB and λ5, as well as the signal-transducing heterodimer Igα/Igβ. Signaling through the pre-BCR regulates allelic exclusion at the Ig H locus, stimulates cell proliferation, and induces differentiation to small post-mitotic pre-B cells that further undergo the rearrangement of the IgL chain genes. Recent advances in elucidating the key roles of pre-BCR in B cell development have provided a better understanding of normal B lymphopoiesis and its dysregulated state leading to B cell neoplasia.

  7. Comparative In Vitro Immune Stimulation Analysis of Primary Human B Cells and B Cell Lines

    Science.gov (United States)

    Van Belle, Kristien; Herman, Jean; Boon, Louis; Waer, Mark

    2016-01-01

    B cell specific immunomodulatory drugs still remain an unmet medical need. Utilisation of validated simplified in vitro models would allow readily obtaining new insights in the complexity of B cell regulation. For this purpose we investigated which human B lymphocyte stimulation assays may be ideally suited to investigate new B lymphocyte immunosuppressants. Primary polyclonal human B cells underwent in vitro stimulation and their proliferation, production of immunoglobulins (Igs) and of cytokines, and expression of cell surface molecules were analysed using various stimuli. ODN2006, a toll-like receptor 9 (TLR9) agonist, was the most potent general B cell stimulus. Subsequently, we investigated on which human B cell lines ODN2006 evoked the broadest immunostimulatory effects. The Namalwa cell line proved to be the most responsive upon TLR9 stimulation and hence may serve as a relevant, homogeneous, and stable B cell model in an in vitro phenotypic assay for the discovery of new targets and inhibitors of the B cell activation processes. As for the read-out for such screening assay, it is proposed that the expression of activation and costimulatory surface markers reliably reflects B lymphocyte activation. PMID:28116319

  8. B Cell-Activating Factor Regulates Different Aspects of B Cell Functionality and Is Produced by a Subset of Splenic B Cells in Teleost Fish.

    Science.gov (United States)

    Tafalla, Carolina; González, Lucia; Castro, Rosario; Granja, Aitor G

    2017-01-01

    In mammals, B cell functionality is greatly influenced by cytokines released by innate cells, such as macrophages or dendritic cells, upon the early recognition of common pathogen patterns through invariant receptors. B cell-activating factor (BAFF) is one of these innate B cell-helper signals and plays a key role in the survival and differentiation of B cells. Although, evolutionarily, teleost fish constitute the first animal group in which adaptive immunity based on Ig receptors is present, fish still rely greatly on innate responses. In this context, we hypothesized that BAFF would play a key role in the control of B cell responses in fish. Supporting this, our results show that teleost BAFF recapitulates mammalian BAFF stimulating actions on B cells, upregulating the expression of membrane MHC II, improving the survival of fish naïve B cells and antibody-secreting cells, and increasing the secretion of IgM. Surprisingly, we also demonstrate that BAFF is not only produced in fish by myeloid cells but is also produced by a subset of splenic B cells. Thus, if this B cell-produced BAFF proves to be actively regulating this same B cell subset, our findings point to an ancient mechanism to control B cell differentiation and survival in lower vertebrates, which has been silenced in mammals in physiological conditions, but reemerges under pathological conditions, such as B cell lymphomas and autoimmune diseases.

  9. Advances in human B cell phenotypic profiling

    Directory of Open Access Journals (Sweden)

    Denise A Kaminski

    2012-10-01

    Full Text Available To advance our understanding and treatment of disease, research immunologists have been called-upon to place more centralized emphasis on impactful human studies. Such endeavors will inevitably require large-scale study execution and data management regulation (Big Biology, necessitating standardized and reliable metrics of immune status and function. A well-known example setting this large-scale effort in-motion is identifying correlations between eventual disease outcome and T lymphocyte phenotype in large HIV-patient cohorts using multiparameter flow cytometry. However, infection, immunodeficiency, and autoimmunity are also characterized by correlative and functional contributions of B lymphocytes, which to-date have received much less attention in the human Big Biology enterprise. Here, we review progress in human B cell phenotyping, analysis, and bioinformatics tools that constitute valuable resources for the B cell research community to effectively join in this effort.

  10. 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.

  11. Recurrent Hepatitis C Post-Transplantation: Where Are We Now and Where Do We Go From Here? A Report from the Canadian Transplant Hepatology Workshop

    Directory of Open Access Journals (Sweden)

    Kymberly DS Watt

    2006-01-01

    Full Text Available Approximately 400 liver transplants are performed in Canada every year and close to 6000 per year in the United States. Forty per cent to 45% of all liver transplants are performed for patients with underlying hepatitis C virus (HCV-related liver disease. These patients have a different natural history, new complication risks and different treatment efficacy than nontransplant HCV patients. Every effort must be made to identify those patients at highest risk for progressive liver disease post-transplant. Recurrent HCV is an Achilles’ heel to transplant hepatology. The true natural history of this disease is only starting to unravel and many questions remain unanswered on the optimal management of these patients after liver transplantation. The present report summarizes the literature and ongoing research needs that are specific to HCV-related liver transplantation.

  12. [Reccurent Clostridium difficile infection in patient after kidney transplantation on rituximab therapy due to PTLD (Post-Transplant Lymphoprolipherative Disorder). First experience with Fidaxomicin use--case report].

    Science.gov (United States)

    Cieniawski, Dominik; Ignacak, Ewa; Bętkowska-Prokop, Alina; Dudzik, Barbara; Walatek, Bogusław; Kuźniewski, Marek; Sułowicz, Władysław

    2014-01-01

    Clostridium difficile infection (CDI) is an increasingly problem in everyday clinical practice. The most important risk factor of this infection is antibiotics use. The incidence of Clostridium difficile associated diarrhea (CDAD) in patients after renal transplantation is estimated to be about 6% in the early postoperative period. Due to the applied immunosuppression and frequent infections requiring intensive, broad spectral antibiotics, the later prevalence of CDAD may remain at a similar level. Massive diarrhea caused by Clostridium difficile may lead to fluctuations in immunosuppressive drugs concentration, in renal transplant patients. The authors present a case study of a 23-year old patient after kidney transplantation from deceased donor, with diagnosed polymorphic PTLD (Post-Transplant Lymphoproliferative Disorder). During biological treatment with rituximab in this patient 4 recurrences of CDI were observed. In this article the clinical manifestation of recurrent CDAD are presented. The authors discuss therapeutic procedure with fidaxomicin use, its results and influence on immunosuppressive drugs concentration.

  13. Role of Epstein-Barr virus status and immunophenotypic studies in the evaluation of exfoliative cytology specimens from patients with post-transplant lymphoproliferative disorders.

    Science.gov (United States)

    Gibson, Sarah E; Picarsic, Jennifer; Swerdlow, Steven H; Pantanowitz, Liron

    2016-06-01

    Post-transplant lymphoproliferative disorders (PTLDs) are well characterized in tissue sections, but their evaluation in exfoliative cytology specimens is limited. This study reports a 25-year experience with PTLDs in exfoliative cytology specimens. All solid organ or allogeneic stem cell transplant recipients with PTLDs and exfoliative cytology specimens from 1987 to 2011 were identified. The cytomorphology, Epstein-Barr virus (EBV) status, flow cytometry, immunohistochemistry, and molecular studies were reviewed from all exfoliative cytology specimens previously diagnosed as atypical lymphoid proliferations or PTLDs. A total of 55 patients (age range, 1-72 years) with PTLDs had 434 exfoliative cytology specimens. Thirty-six of the 55 patients (65%) had 54 specimens with abnormal lymphoid proliferations (12% of the specimens), and 26 of these patients had 37 specimens available for review (15 cerebrospinal fluid specimens, 12 peritoneal fluid specimens, 9 pleural fluid specimens, and 1 bronchoalveolar lavage fluid specimen). Thirty percent of the reviewed cytology specimens were diagnostic of PTLDs, including 8 cases of monomorphic post-transplant lymphoproliferative disorder (M-PTLD) with abnormal B/T-cell populations identified with flow cytometry/immunohistochemistry and 3 EBV-positive specimens with a differential diagnosis of polymorphic PTLD versus M-PTLD. All cases diagnostic of a PTLD had 1 to 3 ancillary studies performed. Forty percent of the cytology specimens (15 of 37) were suspicious for a PTLD, but ancillary studies were performed for only a third of them, and they did not support a definitive diagnosis of a PTLD. Thirty percent of the cytology specimens (11 of 37) appeared reactive, but they lacked sufficient ancillary studies to exclude a PTLD. Atypical lymphoid proliferations are common in exfoliative cytology specimens from patients with PTLDs, and they require ancillary studies at least including immunophenotyping and EBV evaluations for a

  14. Impaired interferon-alpha production by plasmacytoid dendritic cells after cord blood transplantation in children: implication for post-transplantation toll-like receptor ligand-based immunotherapy.

    Science.gov (United States)

    Charrier, Emily; Cordeiro, Paulo; Brito, Rose-Marie; Harnois, Michaël; Mezziani, Samira; Herblot, Sabine; Le Deist, Françoise; Duval, Michel

    2014-10-01

    Plasmacytoid dendritic cells (pDCs) initiate both innate and adaptive immune responses, making them attractive targets for post-transplantation immunotherapy, particularly after cord blood transplantation (CBT). Toll-like receptor (TLR) agonists are currently studied for pDC stimulation in various clinical settings. Their efficacy depends on pDC number and functionality, which are unknown after CBT. We performed a longitudinal study of pDC reconstitution in children who underwent bone marrow transplantation (BMT) and single-unit CBT. Both CBT and unrelated BMT patients received antithymocyte globulin as part of their graft-versus-host disease prophylaxis regimen. pDC blood counts were higher in CBT patients than in healthy volunteers from 2 to 9 months after transplantation, whereas they remained lower in BMT patients. We showed that cord blood progenitors gave rise in vitro to a 500-fold increase in functional pDCs over bone marrow counterparts. Upon stimulation with a TLR agonist, pDCs from both CBT and BMT recipients upregulated T cell costimulatory molecules, whereas interferon-alpha (IFN-α) production was impaired for 9 months after CBT. TLR agonist treatment is thus not expected to induce IFN-α production by pDCs after CBT, limiting its immunotherapeutic potential. Fortunately, in vitro production of large amounts of functional pDCs from cord blood progenitors paves the way for the post-transplantation adoptive transfer of pDCs. Copyright © 2014 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  15. Post-Transplant Cyclophosphamide and Tacrolimus-Mycophenolate Mofetil Combination Prevents Graft-versus-Host Disease in Allogeneic Peripheral Blood Hematopoietic Cell Transplantation from HLA-Matched Donors.

    Science.gov (United States)

    Carnevale-Schianca, Fabrizio; Caravelli, Daniela; Gallo, Susanna; Coha, Valentina; D'Ambrosio, Lorenzo; Vassallo, Elena; Fizzotti, Marco; Nesi, Francesca; Gioeni, Luisa; Berger, Massimo; Polo, Alessandra; Gammaitoni, Loretta; Becco, Paolo; Giraudo, Lidia; Mangioni, Monica; Sangiolo, Dario; Grignani, Giovanni; Rota-Scalabrini, Delia; Sottile, Antonino; Fagioli, Franca; Aglietta, Massimo

    2017-03-01

    Allogeneic hematopoietic cell transplant (HCT) remains the only curative therapy for many hematologic malignancies but it is limited by high nonrelapse mortality (NRM), primarily from unpredictable control of graft-versus-host disease (GVHD). Recently, post-transplant cyclophosphamide demonstrated improved GVHD control in allogeneic bone marrow HCT. Here we explore cyclophosphamide in allogeneic peripheral blood stem cell transplantation (alloPBSCT). Patients with high-risk hematologic malignancies received alloPBSCT from HLA-matched unrelated/related donors. GVHD prophylaxis included combination post-HCT cyclophosphamide 50 mg/kg (days +3 and +4) and tacrolimus/mofetil mycophenolate (T/MMF) (day +5 forward). The primary objective was the cumulative incidence of acute and chronic GVHD. Between March 2011 and May 2015, 35 consecutive patients received the proposed regimen. MMF was stopped in all patients at day +28; the median discontinuation of tacrolimus was day +113. Acute and chronic GVHD cumulative incidences were 17% and 7%, respectively, with no grade IV GVHD events, only 2 patients requiring chronic GVHD immunosuppression control, and no deaths from GVHD. Two-year NRM, overall survival, event-free survival, and chronic GVHD event-free survival rates were 3%, 77%, 54%, and 49%, respectively. The graft-versus-tumor effect was maintained as 5 of 15 patients (33%) who received HCT with evidence of disease experienced further disease response. A post-transplant cyclophosphamide + T/MMF combination strategy effectively prevented acute and chronic GVHD after alloPBSCT from HLA-matched donors and achieved an unprecedented low NRM without losing efficacy in disease control or impaired development of the graft-versus-tumor effect. This trial is registered at clinicaltrials.gov as NCT02300571.

  16. Management of Epstein-Barr Virus infections and post-transplant lymphoproliferative disorders in patients after allogeneic hematopoietic stem cell transplantation: Sixth European Conference on Infections in Leukemia (ECIL-6) guidelines.

    Science.gov (United States)

    Styczynski, Jan; van der Velden, Walter; Fox, Christopher P; Engelhard, Dan; de la Camara, Rafael; Cordonnier, Catherine; Ljungman, Per

    2016-07-01

    Epstein-Barr virus-related post-transplant lymphoproliferative disorders are recognized as a significant cause of morbidity and mortality in patients undergoing hematopoietic stem cell transplantation. To better define current understanding of post-transplant lymphoproliferative disorders in stem cell transplant patients, and to improve its diagnosis and management, a working group of the Sixth European Conference on Infections in Leukemia 2015 reviewed the literature, graded the available quality of evidence, and developed evidence-based recommendations for diagnosis, prevention, prophylaxis and therapy of post-transplant lymphoproliferative disorders exclusively in the stem cell transplant setting. The key elements in diagnosis include non-invasive and invasive methods. The former are based on quantitative viral load measurement and imaging with positron emission tomography; the latter with tissue biopsy for histopathology and detection of Epstein-Barr virus. The diagnosis of post-transplant lymphoproliferative disorder can be established on a proven or probable level. Therapeutic strategies include prophylaxis, preemptive therapy and targeted therapy. Rituximab, reduction of immunosuppression and Epstein-Barr virus-specific cytotoxic T-cell therapy are recommended as first-line therapy, whilst unselected donor lymphocyte infusions or chemotherapy are options as second-line therapy; other methods including antiviral drugs are discouraged.

  17. Epstein-Barr virus-positive post-transplant lymphoproliferative disorder of the central nervous system, after renal transplantation with a discrepancy in viral load between peripheral blood and cerebrospinal fluid

    NARCIS (Netherlands)

    Boersma, Marijke Nynke; van der Zanden, Adri; Laverman, Gozewijn Dirk; Sanders, Jan Stephan; de Vries, Peter Alexander Marcel

    2012-01-01

    A 43-year-old female developed an EpsteinBarr virus (EBV)-positive post-transplant lymphoproliferative disorder (PTLD) in the central nervous system (CNS), 14 years after renal transplantation. One year prior to presentation, the patients treatment regimen was altered from cyclosporine, azathioprine

  18. Pharm GKB: Leukemia, B-Cell, Acute [PharmGKB

    Lifescience Database Archive (English)

    Full Text Available UTR Alleles, Functions, and Amino Acid Translations are all sourced from dbSNP 144 Overview Alternate Names: Synonym Acute... B-Cell Leukemia; Acute B-Cell Leukemias; Acute B-Lymphocytic Leukemia; Acute... B-Lymphocytic Leukemias; Acute lymphoblastic leukaemia, Burkitt's type; Acute lymphoblastic leuka...emia, mature B-cell type; Acute lymphoblastic leukemia, Burkitt's type; Acute lymphoblastic leukemia, mature... B-cell type; B Cell Leukemia, Acute; B Lymphocytic Leukemia, Acute; B-ALL; B-Cell Leukemia, Acute

  19. A B-Cell Superantigen Induces the Apoptosis of Murine and Human Malignant B Cells

    Science.gov (United States)

    Lorenzo, Daniela; Duarte, Alejandra; Mundiñano, Juliana; Berguer, Paula; Nepomnaschy, Irene; Piazzon, Isabel

    2016-01-01

    B-cell superantigens (Sags) bind to conserved sites of the VH or VL regions of immunoglobulin molecules outside their complementarity-determining regions causing the apoptosis of normal cognate B cells. No attempts to investigate whether B-cell Sags are able to induce the apoptosis of cognate malignant B cells were reported. In the present study we show that protein L (PpL), secreted by Finegoldia magna, a B-cell Sag which interacts with κ+ bearing cells, induces the apoptosis of murine and human κ+ lymphoma B cells both in vitro and in vivo. Apoptosis was not altered by caspase-8 inhibitor. No alterations in the levels of Bid, Fas and Fas-L were found suggesting that PpL does not activate the extrinsic pathway of apoptosis. The involvement of the intrinsic pathway was clearly indicated by: i) alterations in mitochondrial membrane potential (ΔΨm) both in murine and human lymphoma cells exposed to PpL; ii) decreased levels of apoptosis in the presence of caspase-9 inhibitor; iii) significant increases of Bim and Bax protein levels and downregulation of Bcl-2; iv) the translocation from the cytoplasm to the mitochondria of Bax and Bim pro-apoptotic proteins and its inhibition by caspase-9 inhibitor but not by caspase-8 inhibitor and v) the translocation of Bcl-2 protein from the mitochondria to the cytosol and its inhibition by caspase-9 inhibitor but not by caspase-8 inhibitor. The possibility of a therapeutic use of Sags in lymphoma/leukemia B cell malignancies is discussed. PMID:27603942

  20. Large B-cell lymphoma arising in cardiac myxoma or intracardiac fibrinous mass: a localized lymphoma usually associated with Epstein-Barr virus?

    Science.gov (United States)

    Aguilar, Cristian; Beltran, Brady; Quiñones, Pilar; Carbajal, Tomas; Vilcapaza, Jorge; Yabar, Alejandro; Segura, Pedro; Quintanilla-Martinez, Leticia; Miranda, Roberto N; Castillo, Jorge J

    2015-01-01

    Primary cardiac neoplasms are rare. However, among them, cardiac myxoma is the most common tumor. In contrast, primary cardiac lymphoma within a cardiac myxoma is extremely rare and might be difficult to diagnose because of non-specific clinical manifestations. We report the case of a previously healthy 52-year-old man who presented with acute onset of transient dysarthria and left hemiplegia. A transthoracic echocardiography showed a 6×2.5-cm solid mass in the left atrium, which was subsequently resected. Histological, immunohistochemical, and molecular analyses revealed an EBV-associated CD30-positive large B-cell lymphoma with anaplastic morphology within a cardiac myxoma and fibrinous material. Staging studies showed no evidence of lymphoma elsewhere. The patient achieved complete remission and is alive 42 months after diagnosis, and did not receive chemotherapy. We discuss the clinical and pathologic features of lymphoma arising in cardiac myxoma or in intra-atrial fibrinoid mass and the potential role of IL-6 in its pathogenesis.

  1. NKT Cell Responses to B Cell Lymphoma

    Directory of Open Access Journals (Sweden)

    Junxin Li

    2014-04-01

    Full Text Available 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. Epstein-Barr virus LMP2A signaling in statu nascendi mimics a B cell antigen receptor-like activation signal

    Directory of Open Access Journals (Sweden)

    Engels Niklas

    2012-04-01

    Full Text Available Abstract Background The latent membrane protein (LMP 2A of Epstein-Barr virus (EBV is expressed during different latency stages of EBV-infected B cells in which it triggers activation of cytoplasmic protein tyrosine kinases. Early studies revealed that an immunoreceptor tyrosine-based activation motif (ITAM in the cytoplasmic N-terminus of LMP2A can trigger a transient increase of the cytosolic Ca2+ concentration similar to that observed in antigen-activated B cells when expressed as a chimeric transmembrane receptor. Even so, LMP2A was subsequently ascribed an inhibitory rather than an activating function because its expression seemed to partially inhibit B cell antigen receptor (BCR signaling in EBV-transformed B cell lines. However, the analysis of LMP2A signaling has been hampered by the lack of cellular model systems in which LMP2A can be studied without the influence of other EBV-encoded factors. Results We have reanalyzed LMP2A signaling using B cells in which LMP2A is expressed in an inducible manner in the absence of any other EBV signaling protein. This allowed us for the first time to monitor LMP2A signaling in statu nascendi as it occurs during the EBV life cycle in vivo. We show that mere expression of LMP2A not only stimulated protein tyrosine kinases but also induced phospholipase C-γ2-mediated Ca2+ oscillations followed by activation of the extracellular signal-regulated kinase (Erk mitogen-activated protein kinase pathway and induction of the lytic EBV gene bzlf1. Furthermore, expression of the constitutively phosphorylated LMP2A ITAM modulated rather than inhibited BCR-induced Ca2+ mobilization. Conclusion Our data establish that LMP2A expression has a function beyond the putative inhibition of the BCR by generating a ligand-independent cellular activation signal that may provide a molecular switch for different EBV life cycle stages and most probably contributes to EBV-associated lymphoproliferative disorders.

  3. Diffuse Large B-Cell Lymphoma

    Science.gov (United States)

    Friedberg, Jonathan W.

    2008-01-01

    Synopsis Diffuse Large B-Cell Lymphoma (DLBCL) remains a curable lymphoma, with improved outcome due in large part to incorporation of rituximab in standard regimens. The disease is heterogeneous clinically, morphologically, and molecularly. Recent insights into the molecular heterogeneity of DLBCL are beginning to yield novel therapeutics with significant promise for key subsets of patients. Although CHOP chemotherapy with rituximab remains a standard therapeutic approach for most patients with DLBCL, we anticipate that novel agents will be included in treatment regimens for many patients in the near future. PMID:18954744

  4. Dynamics of B cells in germinal centres.

    Science.gov (United States)

    De Silva, Nilushi S; Klein, Ulf

    2015-03-01

    Humoral immunity depends on the germinal centre (GC) reaction during which somatically mutated high-affinity memory B cells and plasma cells are generated. Recent studies have uncovered crucial cues that are required for the formation and the maintenance of GCs and for the selection of high-affinity antibody mutants. In addition, it is now clear that these events are promoted by the dynamic movements of cells within and between GCs. These findings have resolved the complexities of the GC reaction in greater detail than ever before. This Review focuses on these recent advances and discusses their implications for the establishment of humoral immunity.

  5. Chronic B-Cell Leukemias and Agent Orange

    Science.gov (United States)

    ... Enter ZIP code here Enter ZIP code here Chronic B-cell Leukemias and Agent Orange Veterans who ... receive VA health care and disability compensation. About chronic B-cell leukemias Leukemia is a cancer of ...

  6. The origin of marginal zone B cells in the rat

    NARCIS (Netherlands)

    Dammers, PM; de Boer, NK; Deenen, GJ; Nieuwenhuis, P; Kroese, FGM

    1999-01-01

    The marginal zone is a unique compartment that is only found in the spleen. Rat marginal zone B cells (MZ-B) can be distinguished from other B cells, e.g. recirculating follicular B cells (RF-B), by several phenotypic characteristics. Typically MZ-B cells are surface (s)IgM(hi), sIgD(lo) and CD45R(B

  7. Activation-Induced Cytidine Deaminase Expression in Human B Cell Precursors Is Essential for Central B Cell Tolerance.

    Science.gov (United States)

    Cantaert, Tineke; Schickel, Jean-Nicolas; Bannock, Jason M; Ng, Yen-Shing; Massad, Christopher; Oe, Tyler; Wu, Renee; Lavoie, Aubert; Walter, Jolan E; Notarangelo, Luigi D; Al-Herz, Waleed; Kilic, Sara Sebnem; Ochs, Hans D; Nonoyama, Shigeaki; Durandy, Anne; Meffre, Eric

    2015-11-17

    Activation-induced cytidine deaminase (AID), the enzyme-mediating class-switch recombination (CSR) and somatic hypermutation (SHM) of immunoglobulin genes, is essential for the removal of developing autoreactive B cells. How AID mediates central B cell tolerance remains unknown. We report that AID enzymes were produced in a discrete population of immature B cells that expressed recombination-activating gene 2 (RAG2), suggesting that they undergo secondary recombination to edit autoreactive antibodies. However, most AID+ immature B cells lacked anti-apoptotic MCL-1 and were deleted by apoptosis. AID inhibition using lentiviral-encoded short hairpin (sh)RNA in B cells developing in humanized mice resulted in a failure to remove autoreactive clones. Hence, B cell intrinsic AID expression mediates central B cell tolerance potentially through its RAG-coupled genotoxic activity in self-reactive immature B cells.

  8. 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.

  9. 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

  10. Role of prolactin in B cell regulation in multiple sclerosis.

    Science.gov (United States)

    Correale, Jorge; Farez, Mauricio F; Ysrraelit, María Célica

    2014-04-15

    The role of prolactin in MS pathogenesis was investigated. Prolactin levels were higher in MS subjects both during remission and exacerbation compared to control subjects. Prolactin increased JAK2 expression and Stat phosphorylation on B cells, up-regulated anti-MOG antibody secreting cell numbers, BAFF levels, and Bcl-2expression, and down-regulated expression of Trp63. Prolactin levels correlated positively with anti-MOG secreting cell numbers, and negatively with induced apoptotic B cells. Additionally, prolactin decreased B cell receptor-mediated activation threshold, and induced CD40 expression in B cells. These findings suggest that prolactin promotes B cell autoreactivity in MS through different mechanisms.

  11. Clinical Consequences of Defects in B cell Development

    OpenAIRE

    Vale, Andre M.; Schroeder, Harry (Trey) W

    2010-01-01

    Abnormalities in humoral immunity typically reflect a generalized or selective failure of effective B cell development. The developmental processes can be followed through analysis of cell surface markers such as IgM, IgD, CD10, CD19, CD20, CD21, and CD38. Early phases of B cell development are devoted to the creation of immunoglobulin and testing B cell antigen receptor signaling. Failure leads to the absence of B cells and immunoglobulin in the blood from birth. As the developing B cells be...

  12. 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

    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...... 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...

  13. Effect of B-cell receptor engagement on CD40-stimulated B cells

    NARCIS (Netherlands)

    Schilizzi, BM; Boonstra, R; The, TH; deLeij, LFMH

    1997-01-01

    Activation of human B cells in vitro either by cross-linking of surface immunoglobulins (sig) or by triggering CD40 antigen, in the presence of interleukin-10 (IL-10) and interleukin-2 (IL-2), may result in high levels of immunoglobulin secretion in vitro. We studied the combined effects of ligation

  14. Rationally designed BCL6 inhibitors target activated B cell diffuse large B cell lymphoma.

    Science.gov (United States)

    Cardenas, Mariano G; Yu, Wenbo; Beguelin, Wendy; Teater, Matthew R; Geng, Huimin; Goldstein, Rebecca L; Oswald, Erin; Hatzi, Katerina; Yang, Shao-Ning; Cohen, Joanna; Shaknovich, Rita; Vanommeslaeghe, Kenno; Cheng, Huimin; Liang, Dongdong; Cho, Hyo Je; Abbott, Joshua; Tam, Wayne; Du, Wei; Leonard, John P; Elemento, Olivier; Cerchietti, Leandro; Cierpicki, Tomasz; Xue, Fengtian; MacKerell, Alexander D; Melnick, Ari M

    2016-09-01

    Diffuse large B cell lymphomas (DLBCLs) arise from proliferating B cells transiting different stages of the germinal center reaction. In activated B cell DLBCLs (ABC-DLBCLs), a class of DLBCLs that respond poorly to current therapies, chromosomal translocations and amplification lead to constitutive expression of the B cell lymphoma 6 (BCL6) oncogene. The role of BCL6 in maintaining these lymphomas has not been investigated. Here, we designed small-molecule inhibitors that display higher affinity for BCL6 than its endogenous corepressor ligands to evaluate their therapeutic efficacy for targeting ABC-DLBCL. We used an in silico drug design functional-group mapping approach called SILCS to create a specific BCL6 inhibitor called FX1 that has 10-fold greater potency than endogenous corepressors and binds an essential region of the BCL6 lateral groove. FX1 disrupted formation of the BCL6 repression complex, reactivated BCL6 target genes, and mimicked the phenotype of mice engineered to express BCL6 with corepressor binding site mutations. Low doses of FX1 induced regression of established tumors in mice bearing DLBCL xenografts. Furthermore, FX1 suppressed ABC-DLBCL cells in vitro and in vivo, as well as primary human ABC-DLBCL specimens ex vivo. These findings indicate that ABC-DLBCL is a BCL6-dependent disease that can be targeted by rationally designed inhibitors that exceed the binding affinity of natural BCL6 ligands.

  15. Value of the first post-transplant biopsy for predicting long-term cardiac allograft vasculopathy (CAV and graft failure in heart transplant patients.

    Directory of Open Access Journals (Sweden)

    Carlos A Labarrere

    Full Text Available BACKGROUND: Cardiac allograft vasculopathy (CAV is the principal cause of long-term graft failure following heart transplantation. Early identification of patients at risk of CAV is essential to target invasive follow-up procedures more effectively and to establish appropriate therapies. We evaluated the prognostic value of the first heart biopsy (median: 9 days post-transplant versus all biopsies obtained within the first three months for the prediction of CAV and graft failure due to CAV. METHODS AND FINDINGS: In a prospective cohort study, we developed multivariate regression models evaluating markers of atherothrombosis (fibrin, antithrombin and tissue plasminogen activator [tPA] and endothelial activation (intercellular adhesion molecule-1 in serial biopsies obtained during the first three months post-transplantation from 172 patients (median follow-up = 6.3 years; min = 0.37 years, max = 16.3 years. Presence of fibrin was the dominant predictor in first-biopsy models (Odds Ratio [OR] for one- and 10-year graft failure due to CAV = 38.70, p = 0.002, 95% CI = 4.00-374.77; and 3.99, p = 0.005, 95% CI = 1.53-10.40 and loss of tPA was predominant in three-month models (OR for one- and 10-year graft failure due to CAV = 1.81, p = 0.025, 95% CI = 1.08-3.03; and 1.31, p = 0.001, 95% CI = 1.12-1.55. First-biopsy and three-month models had similar predictive and discriminative accuracy and were comparable in their capacities to correctly classify patient outcomes, with the exception of 10-year graft failure due to CAV in which the three-month model was more predictive. Both models had particularly high negative predictive values (e.g., First-biopsy vs. three-month models: 99% vs. 100% at 1-year and 96% vs. 95% at 10-years. CONCLUSIONS: Patients with absence of fibrin in the first biopsy and persistence of normal tPA in subsequent biopsies rarely develop CAV or graft failure during the next 10 years and potentially could be monitored less invasively

  16. Dengue Virus Directly Stimulates Polyclonal B Cell Activation

    Science.gov (United States)

    Papa, Michelle Premazzi; de Morais, Ana Theresa Silveira; Peçanha, Ligia Maria Torres; de Arruda, Luciana Barros

    2015-01-01

    Dengue infection is associated to vigorous inflammatory response, to a high frequency of activated B cells, and to increased levels of circulating cross-reactive antibodies. We investigated whether direct infection of B cells would promote activation by culturing primary human B lymphocytes from healthy donors with DENV in vitro. B cells were susceptible, but poorly permissive to infection. Even though, primary B cells cultured with DENV induced substantial IgM secretion, which is a hallmark of polyclonal B cell activation. Notably, DENV induced the activation of B cells obtained from either DENV immune or DENV naïve donors, suggesting that it was not dependent on DENV-specific secondary/memory response. B cell stimulation was dependent on activation of MAPK and CD81. B cells cultured with DENV also secreted IL-6 and presented increased expression of CD86 and HLA-DR, which might contribute to B lymphocyte co-stimulatory function. Indeed, PBMCs, but not isolated B cells, secreted high amounts of IgG upon DENV culture, suggesting that interaction with other cell types in vivo might promote Ig isotype switching and IgG secretion from different B cell clones. These findings suggest that activation signaling pathways triggered by DENV interaction with non-specific receptors on B cells might contribute to the exacerbated response observed in dengue patients. PMID:26656738

  17. Rheumatoid factors, B cells and immunoglobulin genes.

    Science.gov (United States)

    Jefferis, R

    1995-04-01

    The paradigm of self, non-self discrimination in the immune system is under review as autoreactive B or T cells are increasingly delineated within normal individuals. The products of autoreactive B cells are, mostly, polyspecific IgM antibodies of low affinity. These 'natural' antibodies include rheumatoid factors (RF) encoded by unmutated germline immunoglobulin genes. In rheumatoid arthritis (RA) the RF may be of the IgM, IgG or IgA isotype, show evidence of somatic mutation and have increased affinity; consistent with maturation of an antigen driven immune response. This response could be initiated or driven by an auto-immunogenic form of IgG or an exogenous cross-reactive antigen. Changes in galactosylation of IgG have been reported to be a valuable diagnostic and prognostic indicator in RA. Speculation that these changes may precipitate some of the disease processes is critically reviewed.

  18. Multiple layers of B cell memory with different effector functions.

    Science.gov (United States)

    Dogan, Ismail; Bertocci, Barbara; Vilmont, Valérie; Delbos, Frédéric; Mégret, Jérome; Storck, Sébastien; Reynaud, Claude-Agnès; Weill, Jean-Claude

    2009-12-01

    Memory B cells are at the center of longstanding controversies regarding the presence of antigen for their survival and their re-engagement in germinal centers after secondary challenge. Using a new mouse model of memory B cell labeling dependent on the cytidine deaminase AID, we show that after immunization with a particulate antigen, B cell memory appeared in several subsets, comprising clusters of immunoglobulin M-positive (IgM(+)) and IgG1(+) B cells in germinal center-like structures that persisted up to 8 months after immunization, as well as IgM(+) and IgG1(+) B cells with a memory phenotype outside of B cell follicles. After challenge, the IgG subset differentiated into plasmocytes, whereas the IgM subset reinitiated a germinal center reaction. This model, in which B cell memory appears in several layers with different functions, reconciles previous conflicting propositions.

  19. A critical role of Rap1b in B-cell trafficking and marginal zone B-cell development.

    Science.gov (United States)

    Chen, Yuhong; Yu, Mei; Podd, Andrew; Wen, Renren; Chrzanowska-Wodnicka, Magdalena; White, Gilbert C; Wang, Demin

    2008-05-01

    B-cell development is orchestrated by complex signaling networks. Rap1 is a member of the Ras superfamily of small GTP-binding proteins and has 2 isoforms, Rap1a and Rap1b. Although Rap1 has been suggested to have an important role in a variety of cellular processes, no direct evidence demonstrates a role for Rap1 in B-cell biology. In this study, we found that Rap1b was the dominant isoform of Rap1 in B cells. We discovered that Rap1b deficiency in mice barely affected early development of B cells but markedly reduced marginal zone (MZ) B cells in the spleen and mature B cells in peripheral and mucosal lymph nodes. Rap1b-deficient B cells displayed normal survival and proliferation in vivo and in vitro. However, Rap1b-deficient B cells had impaired adhesion and reduced chemotaxis in vitro, and lessened homing to lymph nodes in vivo. Furthermore, we found that Rap1b deficiency had no marked effect on LPS-, BCR-, or SDF-1-induced activation of mitogen-activated protein kinases and AKT but clearly impaired SDF-1-mediated activation of Pyk-2, a key regulator of SDF-1-mediated B-cell migration. Thus, we have discovered a critical and distinct role of Rap1b in mature B-cell trafficking and development of MZ B cells.

  20. A Metabolomic Approach (1H HRMAS NMR Spectroscopy) Supported by Histology to Study Early Post-transplantation Responses in Islet-transplanted Livers

    Science.gov (United States)

    Vivot, Kevin; Benahmed, Malika A.; Seyfritz, Elodie; Bietiger, William; Elbayed, Karim; Ruhland, Elisa; Langlois, Allan; Maillard, Elisa; Pinget, Michel; Jeandidier, Nathalie; Gies, Jean-Pierre; Namer, Izzie-Jacques; Sigrist, Séverine; Reix, Nathalie

    2016-01-01

    Intrahepatic transplantation of islets requires a lot of islets because more than 50% of the graft is lost during the 24 hours following transplantation. We analyzed, in a rat model, early post-transplantation inflammation using systemic inflammatory markers, or directly in islet-transplanted livers by immunohistochemistry. 1H HRMAS NMR was employed to investigate metabolic responses associated with the transplantation. Inflammatory markers (Interleukin-6, α2-macroglobulin) are not suitable to follow islet reactions as they are not islet specific. To study islet specific inflammatory events, immunohistochemistry was performed on sections of islet transplanted livers for thrombin (indicator of the instant blood-mediated inflammatory reaction (IBMIR)) and granulocytes and macrophages. We observed a specific correlation between IBMIR and granulocyte and macrophage infiltration after 12 h. In parallel, we identified a metabolic response associated with transplantation: after 12 h, glucose, alanine, aspartate, glutamate and glutathione were significantly increased. An increase of glucose is a marker of tissue degradation, and could be explained by immune cell infiltration. Alanine, aspartate and glutamate are inter-connected in a common metabolic pathway known to be activated during hypoxia. An increase of glutathione revealed the presence of antioxidant protection. In this study, IBMIR visualization combined with 1H HRMAS NMR facilitated the characterization of cellular and molecular pathways recruited following islet transplantation. PMID:27766032

  1. Post transplant lymphoproliferative disease in pediatric solid organ transplant patients: A possible role for [{sup 18}F]-FDG-PET(/CT) in initial staging and therapy monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Falck, C. von [Department of Diagnostic Radiology, Medizinische Hochschule Hannover (Medical School Hanover), Carl-Neuberg-Strasse 1, 30625 Hannover (Germany)], E-mail: Falck.Christian.von@mh-hannover.de; Maecker, B. [Department of Pediatric Hematology and Oncology, Medizinische Hochschule Hannover (Medical School Hanover), Carl-Neuberg-Strasse 1, 30625 Hannover (Germany); Schirg, E. [Department of Diagnostic Radiology, Medizinische Hochschule Hannover (Medical School Hanover), Carl-Neuberg-Strasse 1, 30625 Hannover (Germany); Boerner, A.R.; Knapp, W.H. [Department of Nuclear Medicine, Medizinische Hochschule Hannover (Medical School Hanover), Carl-Neuberg-Strasse 1, 30625 Hannover (Germany); Klein, C. [Department of Pediatric Hematology and Oncology, Medizinische Hochschule Hannover (Medical School Hanover), Carl-Neuberg-Strasse 1, 30625 Hannover (Germany); Galanski, M. [Department of Diagnostic Radiology, Medizinische Hochschule Hannover (Medical School Hanover), Carl-Neuberg-Strasse 1, 30625 Hannover (Germany)

    2007-09-15

    Post transplant lymphoproliferative disease (PTLD) is a severe complication after solid organ or bone marrow transplantation. In pediatric transplant recipients PTLD is the most common malignancy. The aim of this study was to evaluate a possible role for positron emission tomography with [{sup 18}F]-2-fluoro-2-desoxy-glucose (FDG) in the initial staging and in therapy monitoring of pediatric patients suffering from biopsy-proven CD20-positive PTLD after solid organ transplantation. Seven pediatric patients were included. All available imaging studies - CT (n = 15), MRI (n = 16) and PET/PETCT (n = 16) - were reviewed on a lesion by lesion base. The performance of FDG-PET in the initial staging and during therapy with a chimeric anti-CD20 antibody was compared to conventional cross sectional imaging and correlated with the clinical outcome. FDG-PET identified all sites of disease as shown by CT/MRI and helped to clarify the significance of equivocal findings. The initial stage of disease was correctly identified by FDG-PET alone when compared to CT/MRI. During therapy, FDG-PET was superior to conventional cross-sectional imaging in the early evaluation of response.

  2. The majority of human memory B cells recognizing RhD and tetanus resides in IgM+ B cells.

    Science.gov (United States)

    Della Valle, Luciana; Dohmen, Serge E; Verhagen, Onno J H M; Berkowska, Magdalena A; Vidarsson, Gestur; Ellen van der Schoot, C

    2014-08-01

    B cell memory to T cell-dependent (TD) Ags are considered to largely reside in class-switched CD27(+) cells. However, we previously observed that anti-RhD (D) Igs cloned from two donors, hyperimmunized with D(+) erythrocytes, were predominantly of the IgM isotype. We therefore analyzed in this study the phenotype and frequency of D- and tetanus toxoid-specific B cells by culturing B cells in limiting dilution upon irradiated CD40L-expressing EL4.B5 cells and testing the culture supernatant. Most Ag-specific B cells for both TD Ags were found to reside in the IgM-expressing B cells, including CD27(-) B cells, in both hyperimmunized donors and nonhyperimmunized volunteers. Only shortly after immunization a sharp increase in Ag-specific CD27(+)IgG(+) B cells was observed. Next, B cells were enriched with D(+) erythrocyte ghosts and sorted as single cells. Sequencing of IGHV, IGLV, IGKV, and BCL6 genes from these D-specific B cell clones demonstrated that both CD27(-)IgM(+) and CD27(+)IgM(+) B cells harbored somatic mutations, documenting their Ag-selected nature. Furthermore, sequencing revealed a clonal relationship between the CD27(-)IgM(+), CD27(+)IgM(+), and CD27(+)IgG(+) B cell subsets. These data strongly support the recently described multiple layers of memory B cells to TD Ags in mice, where IgM(+) B cells represent a memory reservoir which can re-enter the germinal center and ensure replenishment of class-switched memory CD27(+) B cells from Ag-experienced precursors.

  3. Impairment of B-cell functions during HIV-1 infection.

    Science.gov (United States)

    Amu, Sylvie; Ruffin, Nicolas; Rethi, Bence; Chiodi, Francesca

    2013-09-24

    A variety of B-cell dysfunctions are manifested during HIV-1 infection, as reported early during the HIV-1 epidemic. It is not unusual that the pathogenic mechanisms presented to elucidate impairment of B-cell responses during HIV-1 infection focus on the impact of reduced T-cell numbers and functions, and lack of germinal center formation in lymphoid tissues. To our understanding, however, perturbation of B-cell phenotype and function during HIV-1 infection may begin at several different B-cell developmental stages. These impairments can be mediated by intrinsic B-cell defects as well as by the lack of proper T-cell help. In this review, we will highlight some of the pathways and molecular interactions leading to B-cell impairment prior to germinal center formation and B-cell activation mediated through the B-cell receptor in response to HIV-1 antigens. Recent studies indicate a regulatory role for B cells on T-cell biology and immune responses. We will discuss some of these novel findings and how these regulatory mechanisms could potentially be affected by the intrinsic defects of B cells taking place during HIV-1 infection.

  4. Regulation of VH replacement by B cell receptor-mediated signaling in human immature B cells.

    Science.gov (United States)

    Liu, Jing; Lange, Miles D; Hong, Sang Yong; Xie, Wanqin; Xu, Kerui; Huang, Lin; Yu, Yangsheng; Ehrhardt, Götz R A; Zemlin, Michael; Burrows, Peter D; Su, Kaihong; Carter, Robert H; Zhang, Zhixin

    2013-06-01

    VH replacement provides a unique RAG-mediated recombination mechanism to edit nonfunctional IgH genes or IgH genes encoding self-reactive BCRs and contributes to the diversification of Ab repertoire in the mouse and human. Currently, it is not clear how VH replacement is regulated during early B lineage cell development. In this article, we show that cross-linking BCRs induces VH replacement in human EU12 μHC(+) cells and in the newly emigrated immature B cells purified from peripheral blood of healthy donors or tonsillar samples. BCR signaling-induced VH replacement is dependent on the activation of Syk and Src kinases but is inhibited by CD19 costimulation, presumably through activation of the PI3K pathway. These results show that VH replacement is regulated by BCR-mediated signaling in human immature B cells, which can be modulated by physiological and pharmacological treatments.

  5. A 13 year-old boy with post-transplantation lymphoproliferative disorder presenting with obscure gastrointestinal bleeding: a case report [v1; ref status: indexed, http://f1000r.es/2p0

    Directory of Open Access Journals (Sweden)

    Edith Y. Ho

    2014-04-01

    Full Text Available One well recognized and potentially serious complication of chronic immunosuppression in organ transplant recipients is post-transplantation lymphoproliferative disorders (PTLD. This accounts for 20% of all malignancies in transplant recipients, which is four times higher than the general population1,2. The diagnosis of PTLD is often difficult, due to various manifestations resulting in late diagnosis. We report an unusual presentation of PTLD in a pediatric patient where the diagnosis was achieved only after extensive investigation.

  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. 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.

  8. 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.

  9. Presentation of antigen by B cell subsets. Pt. 4. Defective T-B cell signalling causes inability to present antigen by B cells from immunodeficient mice

    Energy Technology Data Exchange (ETDEWEB)

    Zimecki, Michal [Polish Academy of Sciences, Wroclaw (Poland). Institute of Immunology and Experimental Therapy; Kapp, Judith A. [Emory Univ., Atlanta, GA (United States). School of Medicine

    1994-12-31

    The purpose of this study was to investigate differences in T-B cell signalling between B cells from normal and immunodeficient mice. B cell blasts from normal and immunodeficient mice expressed comparable levels of membrane-associated IL-1. B cells from normal, but not immunodeficient mice, prefixed with glutar-aldehyde and cultured with thymocytes or a T cell line BK33, induce in T cells production of a factor which causes release of IL-1 by macrophages. This factor, preincubated with B cells from immunodeficient mice significantly enhances their APC function. Furthermore, this cytokine induces expression of Lyb-5 alloantigen on B cells from immunodeficient mice. This effect could be blocked by neutralizing antibodies to IL-6 but not to IL-2, IL-4 or GM-CSF. We conclude that immature B cells from immunodeficient (CBA/N x BALB/c)F{sub 1} mice are unable to stimulate interacting T cells to produce IL-6 and therefore are inefficient antigen presenting cells. (author). 30 refs, 2 figs, 3 tabs.

  10. 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.

  11. Transcriptional networks in developing and mature B cells.

    Science.gov (United States)

    Matthias, Patrick; Rolink, Antonius G

    2005-06-01

    The development of B cells from haematopoietic stem cells proceeds along a highly ordered, yet flexible, pathway. At multiple steps along this pathway, cells are instructed by transcription factors on how to further differentiate, and several check-points have been identified. These check-points are initial commitment to lymphocytic progenitors, specification of pre-B cells, entry to the peripheral B-cell pool, maturation of B cells and differentiation into plasma cells. At each of these regulatory nodes, there are transcriptional networks that control the outcome, and much progress has recently been made in dissecting these networks. This article reviews our current understanding of this exciting field.

  12. B-Cell Response during Protozoan Parasite Infections

    Directory of Open Access Journals (Sweden)

    María C. Amezcua Vesely

    2012-01-01

    Full Text Available In this review, we discuss how protozoan parasites alter immature and mature B cell compartment. B1 and marginal zone (MZ B cells, considered innate like B cells, are activated during protozoan parasite infections, and they generate short lived plasma cells providing a prompt antibody source. In addition, protozoan infections induce massive B cell response with polyclonal activation that leads to hypergammaglobulnemia with serum antibodies specific for the parasites and self and/or non related antigens. To protect themselves, the parasites have evolved unique ways to evade B cell immune responses inducing apoptosis of MZ and conventional mature B cells. As a consequence of the parasite induced-apoptosis, the early IgM response and an already establish humoral immunity are affected during the protozoan parasite infection. Moreover, some trypanosomatides trigger bone marrow immature B cell apoptosis, influencing the generation of new mature B cells. Simultaneously with their ability to release antibodies, B cells produce cytokines/quemokines that influence the characteristic of cellular immune response and consequently the progression of parasite infections.

  13. Invited article: inhibition of B cell functions: implications for neurology.

    Science.gov (United States)

    Dalakas, Marinos C

    2008-06-01

    B cells are involved in the pathophysiology of many neurologic diseases, either in a causative or contributory role, via production of autoantibodies, cytokine secretion, or by acting as antigen-presenting cells leading to T cell activation. B cells are clonally expanded in various CNS disorders, such as multiple sclerosis (MS), paraneoplastic CNS disorders, or stiff-person syndrome, and are activated to produce pathogenic autoantibodies in demyelinating neuropathies and myasthenia. B cell activating factor (BAFF) and a proliferating inducing ligand (APRIL), key cytokines for B cell survival, are strongly unregulated in MS brain and in muscles of inflammatory myopathies. Modulation of B cell functions using a series of monoclonal antibodies against CD20+ B cells or the molecules that increase B cell survival, such as BAFF/APRIL and their receptors BAFF-R, TACI, and BCMA, provide a rational approach to the treatment of the aforementioned neurologic disorders. In controlled studies, rituximab, a B cell-depleting monoclonal antibody, has been encouraging in MS and paraproteinemic anti-MAG demyelinating neuropathy, exerting long-lasting remissions. In uncontrolled series, benefit has been reported in several disorders. B cell depletion is a well-tolerated therapeutic option currently explored in the treatment of several autoimmune neurologic disorders.

  14. 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.

  15. Clinical consequences of defects in B-cell development.

    Science.gov (United States)

    Vale, Andre M; Schroeder, Harry W

    2010-04-01

    Abnormalities in humoral immunity typically reflect a generalized or selective failure of effective B-cell development. The developmental processes can be followed through analysis of cell-surface markers, such as IgM, IgD, CD10, CD19, CD20, CD21, and CD38. Early phases of B-cell development are devoted to the creation of immunoglobulin and testing of B-cell antigen receptor signaling. Failure leads to the absence of B cells and immunoglobulin in the blood from birth. As the developing B cells begin to express a surface B-cell receptor, they become subject to negative and positive selection pressures and increasingly depend on survival signals. Defective signaling can lead to selective or generalized hypogammaglobulinemia, even in the presence of normal numbers of B cells. In the secondary lymphoid organs some B cells enter the splenic marginal zone, where preactivated cells lie ready to rapidly respond to T-independent antigens, such as the polysaccharides that coat some microorganisms. Other cells enter the follicle and, with the aid of cognate follicular T cells, divide to help form a germinal center (GC) after their interaction with antigen. In the GC B cells can undergo the processes of class switching and somatic hypermutation. Failure to properly receive T-cell signals can lead to hyper-IgM syndrome. B cells that leave the GC can develop into memory B cells, short-lived plasma cells, or long-lived plasma cells. The latter ultimately migrate back to the bone marrow, where they can continue to produce protective antigen-specific antibodies for decades.

  16. Marginal zone B-cells, a gatekeeper of innate immunity.

    Science.gov (United States)

    Zouali, Moncef; Richard, Yolande

    2011-01-01

    To maintain the integrity of an organism constantly challenged by pathogens, the immune system is endowed with a variety of cell types. B lymphocytes were initially thought to only play a role in the adaptive branch of immunity. However, a number of converging observations revealed that two B-cell subsets, marginal zone (MZ) and B1 cells, exhibit unique developmental and functional characteristics, and can contribute to innate immune responses. In addition to their capacity to mount a local antibody response against type-2 T-cell-independent (TI-2) antigens, MZ B-cells can participate to T-cell-dependent (TD) immune responses through the capture and import of blood-borne antigens to follicular areas of the spleen. Here, we discuss the multiple roles of MZ B-cells in humans, non-human primates, and rodents. We also summarize studies - performed in transgenic mice expressing fully human antibodies on their B-cells and in macaques whose infection with Simian immunodeficiency virus (SIV) represents a suitable model for HIV-1 infection in humans - showing that infectious agents have developed strategies to subvert MZ B-cell functions. In these two experimental models, we observed that two microbial superantigens for B-cells (protein A from Staphylococcus aureus and protein L from Peptostreptococcus magnus) as well as inactivated AT-2 virions of HIV-1 and infectious SIV preferentially deplete innate-like B-cells - MZ B-cells and/or B1 B-cells - with different consequences on TI and TD antibody responses. These data revealed that viruses and bacteria have developed strategies to deplete innate-like B-cells during the acute phase of infection and to impair the antibody response. Unraveling the intimate mechanisms responsible for targeting MZ B-cells in humans will be important for understanding disease pathogenesis and for designing novel vaccine strategies.

  17. Pro-B cells propagated in stromal cell-free cultures reconstitute functional B-cell compartments in immunodeficient mice.

    Science.gov (United States)

    von Muenchow, Lilly; Tsapogas, Panagiotis; Albertí-Servera, Llucia; Capoferri, Giuseppina; Doelz, Marianne; Rolink, Hannie; Bosco, Nabil; Ceredig, Rhodri; Rolink, Antonius G

    2017-02-01

    Up to now long-term in vitro growth of pro-B cells was thought to require stromal cells. However, here we show that fetal liver (FL) and bone marrow (BM) derived pro-B cells can be propagated long-term in stromal cell-free cultures supplemented with IL-7, stem cell factor and FLT3 ligand. Within a week, most cells expressed surface CD19, CD79A, λ5, and VpreB antigens and had rearranged immunoglobulin D-J heavy chain genes. Both FL and BM pro-B cells reconstituted the B-cell compartments of immuno-incompetent Rag2-deficient mice, with FL pro-B cells generating follicular, marginal zone (MZB) and B1a B cells, and BM pro-B cells giving rise mainly to MZB cells. Reconstituted Rag2-deficient mice generated significant levels of IgM and IgG antibodies to a type II T-independent antigen; mice reconstituted with FL pro-B cells generated surprisingly high IgG1 titers. Finally, we show for the first time that mice reconstituted with mixtures of pro-B and pro-T cells propagated in stromal cell-free in vitro cultures mounted a T-cell-dependent antibody response. This novel stromal cell-free culture system facilitates our understanding of B-cell development and might be applied clinically. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. BAFF enhances chemotaxis of primary human B cells: a particular synergy between BAFF and CXCL13 on memory B cells.

    Science.gov (United States)

    Badr, Gamal; Borhis, Gwenoline; Lefevre, Eric A; Chaoul, Nada; Deshayes, Frederique; Dessirier, Valérie; Lapree, Genevieve; Tsapis, Andreas; Richard, Yolande

    2008-03-01

    B-cell-activating factor of the TNF family, (BAFF), and a proliferation-inducing ligand (APRIL) regulate B-lymphocyte survival and activation. We report that BAFF, but not APRIL, increased the chemotactic response of primary human B cells to CCL21, CXCL12, and CXCL13. The BAFF-induced increase in B-cell chemotaxis was totally abolished by blockade of BAFF-R and was strongly dependent on the activation of PI3K/AKT, NF-kappaB, and p38MAPK pathways. BAFF had similar effects on the chemotaxis of naive and memory B cells in response to CCL21 but increased more strongly that of memory B cells to CXCL13 than that of naive B cells. Our findings indicate a previously unreported role for the BAFF/BAFF-R pair in mature B-cell chemotaxis. The synergy between CXCL13 and BAFF produced by stromal cells and follicular dendritic cells may have important implications for B-cell homeostasis, the development of normal B-cell areas, and for the formation of germinal center-like follicles that may be observed in various autoimmune diseases.

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

    Directory of Open Access Journals (Sweden)

    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

  20. Cell-engineered human elastic chondrocytes regenerate natural scaffold in vitro and neocartilage with neoperichondrium in the human body post-transplantation.

    Science.gov (United States)

    Yanaga, Hiroko; Imai, Keisuke; Koga, Mika; Yanaga, Katsu

    2012-10-01

    cartilage. Using our multilayered culture system supplemented with FGF2, elastic chondrocytes produce an ECM and also exhibit an intercellular network; therefore, they are able to maintain tissue integrity post-transplantation. These findings realized a clinical application for generative cartilage surgery.

  1. Which is more suitable for kidney transplantation at the early post-transplantation phase in China - low dosing or standard dosing of enteric-coated mycophenolate sodium?

    Science.gov (United States)

    Ding, C; Xue, W; Tian, P; Ding, X; Pan, X; Xiang, H; Tian, X; Li, Y; Zheng, J

    2014-04-01

    To investigate the pharmacokinetics of enteric-coated mycophenolate sodium (EC-MPS) and the clinical outcome in kidney transplant recipients in the early post-transplantation phase. Then explain which regimen is more suitable for Chinese renal transplant recipients. In total, 60 de novo kidney transplant recipients treated with tacrolimus and steroids were randomised to receive EC-MPS at standard dose (SD; 1440 mg/day; n = 28) or low dose (LD; 1080 mg/day; n = 32). Efficacy parameters, safety and tolerability were assessed over a 6-month study period. Full mycophenolic acid (MPA) areas under the curve (AUCs) were completed on days 3 and 5, whereas a three-point limited sampling strategy (LSS) was utilised for MPA AUC assessments at 2 weeks and months 1, 3 and 6 (the LSS for three-time-point MPA AUC 0-12 h (mg h/l) = 15.99 + 0.87C1 h  + 0.68C2 h  + 7.85C4 h ; r(2)  = 0.8670. The mean AUC levels at day 3 and day 5 in the SD group were significantly higher than in the LD group (57.4 mg·h/l vs. 38.2 mg·h/l and 59.3 mg·h/l vs. 44.8 mg·h/l, respectively, p transplant recipients can be achieved with a higher starting dose. In addition, a SD regimen was as well-tolerated as a LD regimen. Furthermore, early adequate MPA exposure significantly lowered the rate of acute rejection without compromising safety and tolerability. © 2014 John Wiley & Sons Ltd.

  2. Five years results after intrafamilial kidney post-transplant in a case of familial hypomagnesemia due to a claudin-19 mutation

    Directory of Open Access Journals (Sweden)

    Jorge Reis Almeida

    2014-09-01

    Full Text Available Introduction: Familial Hypomagnesaemia with hypercalciuria and nephrocalcinosis, with severe ocular impairment secondary to claudin-19 mutation, is a rare recessive autossomic disorder. Its spectrum includes renal Mg2+ wasting, medullary nephrocalcinosis and progressive chronic renal failure in young people. Objective: To report a case of kidney transplantation father to daughter in a familial occurrence of severe bilateral nephrocalcinosis associated with ocular impairment in a non-consanguineous Brazilian family, in which two daughters had nephrocalcinosis and severe retinopathy. Methods: The index case, a 19 years-old female, had long-lasting past medical history of recurrent urinary tract infections, and the abdominal X-ray revealed bilateral multiple renal calcifications as well as ureteral lithiasis, and she was under haemodialysis. She had the diagnosis of retinitis pigmentosa in the early neonatal period. The other daughter (13 years-old had also nephrocalcinosis with preserved kidney function, retinopathy with severe visual impairment, and in addition, she exhibited hypomagnesaemia = 0.5 mg/dL and hypercalciuria. The other family members (mother, father and son had no clinical disease manifestation. Mutation analysis at claudin-19 revealed two heterozygous missense mutations (P28L and G20D in both affected daughters. The other family members exhibited mutant monoallelic status. In despite of that, the index case underwent intrafamilial living donor kidney transplantation (father. Conclusion: In conclusion, the disease was characterized by an autosomal recessive compound heterozygous status and, after five years of donation the renal graft function remained stable without recurrence of metabolic disturbances or nephrocalcinosis. Besides, donor single kidney Mg2+ and Ca2+ homeostasis associated to monoallelic status did not affect the safety and the usual living donor post-transplant clinical course.

  3. Transitional B cells in early human B cell development - time to revisit the paradigm?

    Directory of Open Access Journals (Sweden)

    Victoria G Martin

    2016-12-01

    Full Text Available The B cell repertoire is generated in the adult bone marrow by an ordered series of gene rearrangement processes that result in massive diversity of immunoglobulin (Ig genes, and consequently an equally large number of potential specificities for antigen. As the process is essentially random, then cells exhibiting excess reactivity with self-antigens are generated and need to be removed from the repertoire before the cells are fully mature. Some of the cells are deleted, and some will undergo receptor editing to see if changing the light chain can rescue an autoreactive antibody. As a consequence, the binding properties of the B cell receptor are changed as development progresses through pre-B>>immature>>transitional>>naïve phenotypes. Using long-read, high-throughput, sequencing we have produced a unique set of sequences from these four cell types in human bone marrow and matched peripheral blood and our results describe the effects of tolerance selection on the B cell repertoire at the Ig gene level. Most strong effects of selection are seen within the heavy chain repertoire, and can be seen both in gene usage and in CDR-H3 characteristics. Age-related changes are small and only the size of the CDR-H3 shows constant and significant change in these data. The paucity of significant changes in either kappa or lambda light chain repertoires implies that either the heavy chain has more influence over autoreactivity than light chain and/or that switching between kappa and lambda light chains, as opposed to switching within the light chain loci, may effect a more successful autoreactive rescue by receptor editing. Our results show that the transitional cell population contains cells other than those that are part of the pre-B>>immature>>transitional>>naïve development pathway, since the population often shows a repertoire that is outside the trajectory of gene loss/gain between pre-B and naïve stages.

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

    DEFF Research Database (Denmark)

    Faurschou, Mikkel; Jayne, David R W

    2014-01-01

    erythematosus, antineutrophil cytoplasmic antibody-associated vasculitis, polymyositis/dermatomyositis, and primary Sjögren's syndrome. For some anti-B cell agents, clinical benefits have been convincingly demonstrated, while other B cell-targeted therapies failed to improve outcomes when added to standard...

  5. Bidirectional regulation between B cells and T cells

    NARCIS (Netherlands)

    Margry, B.

    2014-01-01

    B cells were often thought of as simple precursors of end-stage effector cells that are merely in charge of antibody production. Research in the last decades has shown that B cells possess important other roles as well, including their involvement in the regulation and functioning of T cell-mediated

  6. B cells as therapeutic targets in autoimmune neurological disorders.

    Science.gov (United States)

    Dalakas, Marinos C

    2008-10-01

    B cells have a fundamental role in the pathogenesis of various autoimmune neurological disorders, not only as precursors of antibody-producing cells, but also as important regulators of the T-cell activation process through their participation in antigen presentation, cytokine production, and formation of ectopic germinal centers in the intermeningeal spaces. Two B-cell trophic factors-BAFF (B-cell-activating factor) and APRIL (a proliferation-inducing ligand)-and their receptors are strongly upregulated in many immunological disorders of the CNS and PNS, and these molecules contribute to clonal expansion of B cells in situ. The availability of monoclonal antibodies or fusion proteins against B-cell surface molecules and trophic factors provides a rational approach to the treatment of autoimmune neurological diseases. This article reviews the role of B cells in autoimmune neurological disorders and summarizes the experience to date with rituximab, a B-cell-depleting monoclonal antibody against CD20, for the treatment of relapsing-remitting multiple sclerosis, autoimmune neuropathies, neuromyelitis optica, paraneoplastic neurological disorders, myasthenia gravis, and inflammatory myopathies. It is expected that ongoing controlled trials will establish the efficacy and long-term safety profile of anti-B-cell agents in several autoimmune neurological disorders, as well as exploring the possibility of a safe and synergistic effect with other immunosuppressants or immunomodulators.

  7. Therapeutic strategies targeting B-cells in multiple sclerosis.

    Science.gov (United States)

    Milo, Ron

    2016-07-01

    Multiple sclerosis (MS) is a chronic inflammatory and demyelinating disease of the central nervous system (CNS) that traditionally has been considered to be mediated primarily by T-cells. Increasing evidence, however, suggests the fundamental role of B-cells in the pathogenesis of the disease. Recent strategies targeting B-cells in MS have demonstrated impressive and sometimes surprising results: B-cell depletion by monoclonal antibodies targeting the B-cell surface antigen CD20 (e.g. rituximab, ocrelizumab, ofatumumab) was shown to exert profound anti-inflammatory effect in MS with favorable risk-benefit ratio, with ocrelizumab demonstrating efficacy in both relapsing-remitting (RR) and primary-progressive (PP) MS in phase III clinical trials. Depletion of CD52 expressing T- and B-cells and monocytes by alemtuzumab resulted in impressive and durable suppression of disease activity in RRMS patients. On the other hand, strategies targeting B-cell cytokines such as atacicept resulted in increased disease activity. As our understanding of the biology of B-cells in MS is increasing, new compounds that target B-cells continue to be developed which promise to further expand the armamentarium of MS therapies and allow for more individualized therapy for patients with this complex disease.

  8. A fine romance: T follicular helper cells and B cells.

    Science.gov (United States)

    King, Cecile

    2011-06-24

    T follicular helper (Tfh) cells help B cells to generate affinity-matured antibodies. Three papers in this issue of Immunity (Choi et al., 2011; Kerfoot et al., 2011; Kitano et al., 2011) provide information about the reciprocal relationship between B cells and Tfh cells. Copyright © 2011 Elsevier Inc. All rights reserved.

  9. 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.

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

    Science.gov (United States)

    Gaspar, Miguel; May, Janet S; Sukla, Soumi; Frederico, Bruno; Gill, Michael B; Smith, Christopher M; Belz, Gabrielle T; Stevenson, Philip G

    2011-11-01

    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.

  11. Marginal zone B-cells, a gatekeeper of innate immunity

    Directory of Open Access Journals (Sweden)

    Moncef eZOUALI

    2011-12-01

    Full Text Available To maintain the integrity of an organism constantly challenged by pathogens, the immune system is endowed with a variety of cell types. B-lymphocytes were initially thought to only play a role in the adaptative branch of immunity. However, a number of converging observations revealed that two B-cell subsets, marginal zone (MZ and B1 cells, exhibit unique developmental and functional characteristics, and can contribute to innate immune responses. In addition to their capacity to mount local antibody response against type 2 T-independent (TI-2 antigens, MZ B-cells can participate to T-dependent (TD immune response through the capture and import of blood-borne antigens to follicular areas of the spleen. Here, we discuss the multiple roles of MZ B-cells in rodents and primates. We also summarize studies —performed in transgenic mice expressing fully human antibodies on their B-cells and macaques whose infection with Simian Immunodeficiency Virus (SIV represents a suitable model for HIV-1 infection in humans— showing that infectious agents have developed strategies to subvert MZ B-cell functions. In these two experimental models, we observed that two microbial superantigens for B-cells (protein A from Staphylococcus aureus and protein L from Peptostreptococcus magnus as well as inactivated AT-2 virions of HIV-1 and infectious SIV preferentially deplete innate-like B-cells —MZ B-cells and/or B1 B-cells— with different consequences on TI and TD antibody responses. These data revealed that viruses and bacteria have developed strategies to deplete innate-like B-cells during the acute phase of infection and to impair the antibody response. Unraveling the intimate mechanisms responsible for targeting MZ B-cells in humans will be important for understanding disease pathogenesis and for designing novel vaccine strategies.

  12. Myeloma clonotypic B cells are hampered in their ability to undergo B-cell differentiation in vitro

    NARCIS (Netherlands)

    Guikema, JEJ; Vellenga, E; Bakkus, MHC; Bos, NA

    2002-01-01

    In the peripheral blood (PB) of multiple myeloma (MM) patients, clonotypic B cells are present that express the identical V( D) J rearrangements as the malignant plasma cells in the bone marrow. In the present study, the proliferative capacity of clonotypic B cells from MM patients (n = 10) and the

  13. Prolactin Rescues Immature B-Cells from Apoptosis Induced by B-Cell Receptor Cross-Linking.

    Science.gov (United States)

    Flores-Fernández, Rocio; Blanco-Favela, Francisco; Fuentes-Pananá, Ezequiel M; Chávez-Sánchez, Luis; Gorocica-Rosete, Patricia; Pizaña-Venegas, Alberto; Chávez-Rueda, Adriana Karina

    2016-01-01

    Prolactin has an immunomodulatory effect and has been associated with B-cell-triggered autoimmune diseases, such as systemic lupus erythematosus (SLE). In mice that develop SLE, the PRL receptor is expressed in early bone marrow B-cells, and increased levels of PRL hasten disease manifestations, which are correlated with a reduction in the absolute number of immature B-cells. The aim of this work was to determine the effect of PRL in an in vitro system of B-cell tolerance using WEHI-231 cells and immature B-cells from lupus prone MRL/lpr mice. WEHI-231 cells express the long isoform of the PRL receptor, and PRL rescued the cells from cell death by decreasing the apoptosis induced by the cross-linking of the B-cell antigen receptor (BCR) as measured by Annexin V and active caspase-3. This decrease in apoptosis may have been due to the PRL and receptor interaction, which increased the relative expression of antiapoptotic Bcl-xL and decreased the relative expression of proapoptotic Bad. In immature B-cells from MRL/lpr mice, PRL increased the viability and decreased the apoptosis induced by the cross-linking of BCR, which may favor the maturation of self-reactive B-cells and contribute to the onset of disease.

  14. B-cell receptor signaling inhibitors for treatment of autoimmune inflammatory diseases and B-cell malignancies.

    Science.gov (United States)

    Puri, Kamal D; Di Paolo, Julie A; Gold, Michael R

    2013-08-01

    B-cell receptor (BCR) signaling is essential for normal B-cell development, selection, survival, proliferation, and differentiation into antibody-secreting cells. Similarly, this pathway plays a key role in the pathogenesis of multiple B-cell malignancies. Genetic and pharmacological approaches have established an important role for the Spleen tyrosine kinase (Syk), Bruton's tyrosine kinase (Btk), and phosphatidylinositol 3-kinase isoform p110delta (PI3Kδ) in coupling the BCR and other BCRs to B-cell survival, migration, and activation. In the past few years, several small-molecule inhibitory drugs that target PI3Kδ, Btk, and Syk have been developed and shown to have efficacy in clinical trials for the treatment of several types of B-cell malignancies. Emerging preclinical data have also shown a critical role of BCR signaling in the activation and function of self-reactive B cells that contribute to autoimmune diseases. Because BCR signaling plays a major role in both B-cell-mediated autoimmune inflammation and B-cell malignancies, inhibition of this pathway may represent a promising new strategy for treating these diseases. This review summarizes recent achievements in the mechanism of action, pharmacological properties, and clinical activity and toxicity of these BCR signaling inhibitors, with a focus on their emerging role in treating lymphoid malignancies and autoimmune disorders.

  15. Prolactin Rescues Immature B-Cells from Apoptosis Induced by B-Cell Receptor Cross-Linking

    Science.gov (United States)

    Flores-Fernández, Rocio; Blanco-Favela, Francisco; Fuentes-Pananá, Ezequiel M.; Chávez-Sánchez, Luis; Gorocica-Rosete, Patricia; Pizaña-Venegas, Alberto; Chávez-Rueda, Adriana Karina

    2016-01-01

    Prolactin has an immunomodulatory effect and has been associated with B-cell-triggered autoimmune diseases, such as systemic lupus erythematosus (SLE). In mice that develop SLE, the PRL receptor is expressed in early bone marrow B-cells, and increased levels of PRL hasten disease manifestations, which are correlated with a reduction in the absolute number of immature B-cells. The aim of this work was to determine the effect of PRL in an in vitro system of B-cell tolerance using WEHI-231 cells and immature B-cells from lupus prone MRL/lpr mice. WEHI-231 cells express the long isoform of the PRL receptor, and PRL rescued the cells from cell death by decreasing the apoptosis induced by the cross-linking of the B-cell antigen receptor (BCR) as measured by Annexin V and active caspase-3. This decrease in apoptosis may have been due to the PRL and receptor interaction, which increased the relative expression of antiapoptotic Bcl-xL and decreased the relative expression of proapoptotic Bad. In immature B-cells from MRL/lpr mice, PRL increased the viability and decreased the apoptosis induced by the cross-linking of BCR, which may favor the maturation of self-reactive B-cells and contribute to the onset of disease. PMID:27314053

  16. Prolactin Rescues Immature B-Cells from Apoptosis Induced by B-Cell Receptor Cross-Linking

    Directory of Open Access Journals (Sweden)

    Rocio Flores-Fernández

    2016-01-01

    Full Text Available Prolactin has an immunomodulatory effect and has been associated with B-cell-triggered autoimmune diseases, such as systemic lupus erythematosus (SLE. In mice that develop SLE, the PRL receptor is expressed in early bone marrow B-cells, and increased levels of PRL hasten disease manifestations, which are correlated with a reduction in the absolute number of immature B-cells. The aim of this work was to determine the effect of PRL in an in vitro system of B-cell tolerance using WEHI-231 cells and immature B-cells from lupus prone MRL/lpr mice. WEHI-231 cells express the long isoform of the PRL receptor, and PRL rescued the cells from cell death by decreasing the apoptosis induced by the cross-linking of the B-cell antigen receptor (BCR as measured by Annexin V and active caspase-3. This decrease in apoptosis may have been due to the PRL and receptor interaction, which increased the relative expression of antiapoptotic Bcl-xL and decreased the relative expression of proapoptotic Bad. In immature B-cells from MRL/lpr mice, PRL increased the viability and decreased the apoptosis induced by the cross-linking of BCR, which may favor the maturation of self-reactive B-cells and contribute to the onset of disease.

  17. B cells regulate CD4+ T cell responses to papain following B cell receptor-independent papain uptake.

    Science.gov (United States)

    Dwyer, Daniel F; Woodruff, Matthew C; Carroll, Michael C; Austen, K Frank; Gurish, Michael F

    2014-07-15

    Papain, a cysteine protease allergen with inherent adjuvant activity, induces potent IL-4 expression by T cells in the popliteal lymph nodes of mice following footpad immunization. In this study, we identify a novel, non-BCR-mediated capacity for B cells to rapidly bind and internalize papain. B cells subsequently regulate the adaptive immune response by enhancing ICOS expression on CD4(+) T cells and amplifying Th2 and follicular helper T cell induction. Ab blockade of ICOS ligand, expressed by popliteal lymph node B cells, but not dendritic cells, at the peak of the response inhibits IL-4 responses in wild-type mice but not B cell-deficient mice. Thus, B cells play a critical role in amplifying adjuvant-dependent Th2 polarization following noncanonical acquisition and internalization of the cysteine protease papain.

  18. The rap GTPases regulate B cell morphology, immune-synapse formation, and signaling by particulate B cell receptor ligands.

    Science.gov (United States)

    Lin, Kevin B L; Freeman, Spencer A; Zabetian, Saba; Brugger, Hayley; Weber, Michele; Lei, Victor; Dang-Lawson, May; Tse, Kathy W K; Santamaria, Rene; Batista, Facundo D; Gold, Michael R

    2008-01-01

    B lymphocytes spread and extend membrane processes when searching for antigens and form immune synapses upon contacting cells that display antigens on their surface. Although these dynamic morphological changes facilitate B cell activation, the signaling pathways underlying these processes are not fully understood. We found that activation of the Rap GTPases was essential for these changes in B cell morphology. Rap activation was important for B cell receptor (BCR)- and lymphocyte-function-associated antigen-1 (LFA-1)-induced spreading, for BCR-induced immune-synapse formation, and for particulate BCR ligands to induce localized F-actin assembly and membrane-process extension. Rap activation and F-actin assembly were also required for optimal BCR signaling in response to particulate antigens but not soluble antigens. Thus by controlling B cell morphology and cytoskeletal organization, Rap might play a key role in the activation of B cells by particulate and cell-associated antigens.

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

    Directory of Open Access Journals (Sweden)

    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.

  20. Transitional B Cells in Early Human B Cell Development – Time to Revisit the Paradigm?

    Science.gov (United States)

    Martin, Victoria G.; Wu, Yu-Chang Bryan; Townsend, Catherine L.; Lu, Grace H. C.; O’Hare, Joselli Silva; Mozeika, Alexander; Coolen, Anthonius C. C.; Kipling, David; Fraternali, Franca; Dunn-Walters, Deborah K.

    2016-01-01

    The B cell repertoire is generated in the adult bone marrow by an ordered series of gene rearrangement processes that result in massive diversity of immunoglobulin (Ig) genes and consequently an equally large number of potential specificities for antigen. As the process is essentially random, the cells exhibiting excess reactivity with self-antigens are generated and need to be removed from the repertoire before the cells are fully mature. Some of the cells are deleted, and some will undergo receptor editing to see if changing the light chain can rescue an autoreactive antibody. As a consequence, the binding properties of the B cell receptor are changed as development progresses through pre-B ≫ immature ≫ transitional ≫ naïve phenotypes. Using long-read, high-throughput, sequencing we have produced a unique set of sequences from these four cell types in human bone marrow and matched peripheral blood, and our results describe the effects of tolerance selection on the B cell repertoire at the Ig gene level. Most strong effects of selection are seen within the heavy chain repertoire and can be seen both in gene usage and in CDRH3 characteristics. Age-related changes are small, and only the size of the CDRH3 shows constant and significant change in these data. The paucity of significant changes in either kappa or lambda light chain repertoires implies that either the heavy chain has more influence over autoreactivity than light chain and/or that switching between kappa and lambda light chains, as opposed to switching within the light chain loci, may effect a more successful autoreactive rescue by receptor editing. Our results show that the transitional cell population contains cells other than those that are part of the pre-B ≫ immature ≫ transitional ≫ naïve development pathway, since the population often shows a repertoire that is outside the trajectory of gene loss/gain between pre-B and naïve stages. PMID:27994589

  1. Exploiting human memory B cell heterogeneity for improved vaccine efficacy

    Directory of Open Access Journals (Sweden)

    Noel Thomas Pauli

    2011-12-01

    Full Text Available The major goal in vaccination is establishment of long-term, prophylactic humoral memory to a pathogen. Two major components to long-lived humoral memory are plasma cells for the production of specific immunoglobulin and memory B cells that survey for their specific antigen in the periphery for later affinity maturation, proliferation, and differentiation. The study of human B cell memory has been aided by the discovery of a general marker for B cell memory, expression of CD27; however, new data suggests the existence of CD27- memory B cells as well. These recently described non-canonical memory populations have increasingly pointed to the heterogeneity of the memory compartment. The novel B memory subsets in humans appear to have unique origins, localization, and functions compared to what was considered to be a classical memory B cell. In this article, we review the known B cell memory subsets, the establishment of B cell memory in vaccination and infection, and how understanding these newly described subsets can inform vaccine design and disease treatment.

  2. Salmonella induces PD-L1 expression in B cells.

    Science.gov (United States)

    Lopez-Medina, Marcela; Perez-Lopez, Araceli; Alpuche-Aranda, Celia; Ortiz-Navarrete, Vianney

    2015-10-01

    Salmonella persists for a long time in B cells; however, the mechanism(s) through which infected B cells avoid effector CD8 T cell responses has not been characterized. In this study, we show that Salmonella infects and survives within all B1 and B2 cell subpopulations. B cells are infected with a Salmonella typhimurium strain expressing an ovalbumin (OVA) peptide (SIINFEKL) to evaluate whether B cells process and present Salmonella antigens in the context of MHC-I molecules. Our data showed that OVA peptides are presented by MHC class I K(b)-restricted molecules and the presented antigen is generated through proteasomal degradation and vacuolar processing. In addition, Salmonella-infected B cells express co-stimulatory molecules such as CD40, CD80, and CD86 as well as inhibitory molecules such as PD-L1. Thus, the cross-presentation of Salmonella antigens and the expression of activation molecules suggest that infected B cells are able to prime and activate specific CD8(+) T cells. However, the Salmonella infection-stimulated expression of PD-L1 suggests that the PD-1/PD-L1 pathway may be involved in turning off the cytotoxic effector response during Salmonella persistent infection, thereby allowing B cells to become a reservoir for the bacteria.

  3. YY1 Is Required for Germinal Center B Cell Development.

    Science.gov (United States)

    Banerjee, Anupam; Sindhava, Vishal; Vuyyuru, Raja; Jha, Vibha; Hodewadekar, Suchita; Manser, Tim; Atchison, Michael L

    2016-01-01

    YY1 has been implicated as a master regulator of germinal center B cell development as YY1 binding sites are frequently present in promoters of germinal center-expressed genes. YY1 is known to be important for other stages of B cell development including the pro-B and pre-B cells stages. To determine if YY1 plays a critical role in germinal center development, we evaluated YY1 expression during B cell development, and used a YY1 conditional knock-out approach for deletion of YY1 in germinal center B cells (CRE driven by the immunoglobulin heavy chain γ1 switch region promoter; γ1-CRE). We found that YY1 is most highly expressed in germinal center B cells and is increased 3 fold in splenic B cells activated by treatment with anti-IgM and anti-CD40. In addition, deletion of the yy1 gene by action of γ1-CRE recombinase resulted in significant loss of GC cells in both un-immunized and immunized contexts with corresponding loss of serum IgG1. Our results show a crucial role for YY1 in the germinal center reaction.

  4. [The role of IRA B cells in selected inflammatory processes].

    Science.gov (United States)

    Zasada, Magdalena; Rutkowska-Zapała, Magdalena; Lenart, Marzena; Kwinta, Przemko

    2016-03-16

    The first report about the discovery of new, previously unknown immune cells named IRA B cells (innate response activator B cells) appeared in 2012. So far, their presence has been verified in both mice and humans. However, IRA B cells belong to the family of B lymphocytes and have a number of characteristics unique to this group of cells. IRA B cells are formed from activated B1a lymphocytes after their contact with a pathogen. B1a lymphocytes mainly reside within body cavities. Activated by the pathogen, they move on into secondary lymphoid organs (spleen, lymph nodes) where they differentiate into IRA B cells. IRA B cells are a rich source of granulocyte-macrophage colony stimulating factor (GM-CSF). GM-CSF can stimulate IRA B cells in an autocrine manner for the secretion of intracellular stocks of immunoglobulin M (IgM), which can facilitate pathogens' phagocytosis by neutrophils. GM-CSF also stimulates neutrophils into active phagocytosis. Rapid eradication of the pathogen can prevent the development of an excessive inflammatory response, which can be dangerous for the organism. Until now the involvement of IRA B lymphocytes in the pathogenesis of sepsis and pneumonia has been proven, as well as their role in the progression of atherosclerotic lesions in mice. There is research in progress on the possibility of increasing the number of IRA B cells, for example by intravenous supply of modified immunoglobulins. It is necessary to characterize human IRA B cells and to determine their role in the functioning of the immune system.

  5. Seeking help: B cells adapting to flu variability.

    Science.gov (United States)

    van der Most, Robbert G; Roman, François P; Innis, Bruce; Hanon, Emmanuel; Vaughn, David W; Gillard, Paul; Walravens, Karl; Wettendorff, Martine

    2014-07-23

    The study of influenza vaccines has revealed potential interactions between preexisting immunological memory and antigenic context and/or adjuvantation. In the face of antigenic diversity, the process of generating B cell adaptability is driven by cross-reactive CD4 memory cells, such as T follicular helper cells from previous infections or vaccinations. Although such "helped" B cells are capable of adapting to variant antigens, lack of CD4 help could lead to a suboptimal antibody response. Collectively, this indicates an interplay between CD4 T cells, adjuvant, and B cell adaptability.

  6. B cell development in the bone marrow is regulated by homeostatic feedback exerted by mature B cells

    Directory of Open Access Journals (Sweden)

    Gitit eShahaf

    2016-03-01

    Full Text Available Cellular homeostasis in the B cell compartment is strictly imposed to balance cell production and cell loss. However, it is not clear whether B cell development in the bone marrow (BM is an autonomous process or subjected to regulation by the peripheral B cell compartment. To specifically address this question, we used mice transgenic for human CD20, where effective depletion of B lineage cells is obtained upon administration of mouse-anti-human CD20 antibodies, in the absence of any effect on other cell lineages and/or tissues. We followed the kinetics of B cell return to equilibrium by BrdU labeling and flow cytometry and analyzed the resulting data by mathematical modeling. Labeling was much faster in depleted mice. Compared to control mice, B cell-depleted mice exhibited a higher proliferation rate in the pro-/pre-B compartment, and higher cell death and lower differentiation in the immature B cell compartment. We validated the first result by analysis of the expression of Ki67, the nuclear protein expressed in proliferating cells, and the second using Annexin-V staining. Collectively, our results suggest that B lymphopoiesis is subjected to homeostatic feedback mechanisms imposed by mature B cells in the peripheral compartment.

  7. COMPUTATION MODELING OF TCDD DISRUPTION OF B CELL TERMINAL DIFFERENTIATION

    Science.gov (United States)

    In this study, we established a computational model describing the molecular circuit underlying B cell terminal differentiation and how TCDD may affect this process by impinging upon various molecular targets.

  8. An eruption of European B-cell biology

    OpenAIRE

    2010-01-01

    Volcanic ash clouds disrupted the 2010 ESF/EMBO meeting on B cells and protection. Nevertheless, the delegates who did make it to Catalonia put together their own programme of talks covering a range of themes from mutualism to epigenetics.

  9. B cell-directed therapies in multiple sclerosis.

    Science.gov (United States)

    Gasperi, Christiane; Stüve, Olaf; Hemmer, Bernhard

    2016-01-01

    Multiple sclerosis (MS) is a chronic inflammatory neurological disease of the CNS that goes along with demyelination and neurodegeneration. It is probably caused by an autoimmune response against the CNS, which emerges from the interplay of genetic and environmental factors. Although major progress has been made in the treatment of MS, it is still the leading cause for acquired nontraumatic neurological disability in young adults. Several therapeutic agents have been approved for the treatment of relapsing-remitting MS (RRMS), aiming at the reduction of relapses and a delay in disability progression. Three therapeutic monoclonal antibodies targeting CD20-positive B cells (rituximab, ocrelizumab and ofatumumab) were investigated in MRI-based Phase II and Phase III trials in RRMS, providing consistent evidence for a disease-ameliorating effect of B cell depleting therapies in MS. Here, we discuss the role of B cells and review current and future therapeutic approaches to target B cells in MS.

  10. B cell epitope spreading: mechanisms and contribution to autoimmune diseases.

    Science.gov (United States)

    Cornaby, Caleb; Gibbons, Lauren; Mayhew, Vera; Sloan, Chad S; Welling, Andrew; Poole, Brian D

    2015-01-01

    While a variety of factors act to trigger or initiate autoimmune diseases, the process of epitope spreading is an important contributor in their development. Epitope spreading is a diversification of the epitopes recognized by the immune system. This process happens to both T and B cells, with this review focusing on B cells. Such spreading can progress among multiple epitopes on a single antigen, or from one antigenic molecule to another. Systemic lupus erythematosus, multiple sclerosis, pemphigus, bullous pemphigoid and other autoimmune diseases, are all influenced by intermolecular and intramolecular B cell epitope spreading. Endocytic processing, antigen presentation, and somatic hypermutation act as molecular mechanisms that assist in driving epitope spreading and broadening the immune response in autoimmune diseases. The purpose of this review is to summarize our current understanding of B cell epitope spreading with regard to autoimmunity, how it contributes during the progression of various autoimmune diseases, and treatment options available.

  11. B-Cell waste classification sampling and analysis plan

    Energy Technology Data Exchange (ETDEWEB)

    HOBART, R.L.

    1999-09-22

    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.

  12. [Eosinophilic pneumonia revealing B-cell non-Hodgkin lymphoma].

    Science.gov (United States)

    Fikal, Siham; Sajiai, Hafsa; Serhane, Hind; Aitbatahar, Salma; Amro, Lamyae

    2016-01-01

    The diagnosis of eosinophilic pneumonia is rare and malignant etiology remains exceptional. Eosinophilic pneumonia etiology varies and is mainly dominated by allergic and drug causes. We report the case of a 61-year-old patient with B-cell non-Hodgkin lymphoma revealed by eosinophilic pneumonia. The diagnosis of eosinophilic pneumonia was confirmed by eosinophil count of 56% in bronchoalveolar lavage. Immunohistochemical examination of bone marrow biopsy revealed malignant Small B cells non-Hodgkin lymphoma.

  13. Trafficking of B cell antigen in lymph nodes

    DEFF Research Database (Denmark)

    Gonzalez, Santiago F.; Degn, Søren Egedal; Pitcher, Lisa A.

    2011-01-01

    The clonal selection theory first proposed by Macfarlane Burnet is a cornerstone of immunology ( 1 ). At the time, it revolutionized the thinking of immunologists because it provided a simple explanation for lymphocyte specificity, immunological memory, and elimination of self-reactive clones ( 2......, 5 ) have provided new insights into the trafficking of B cells and their antigen. In this review, we summarize these advances in the context of our current view of B cell circulation and activation....

  14. 324 Facility B-Cell quality process plan

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, J.L.

    1998-03-12

    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.

  15. Altered B cell receptor signaling in human systemic lupus erythematosus

    Science.gov (United States)

    Jenks, Scott A.; Sanz, Iñaki

    2009-01-01

    Regulation of B cell receptor signaling is essential for the development of specific immunity while retaining tolerance to self. Systemic lupus erythematosus (SLE) is characterized by a loss of B cell tolerance and the production of anti-self antibodies. Accompanying this break down in tolerance are alterations in B cell receptor signal transduction including elevated induced calcium responses and increased protein phosphorylation. Specific pathways that negatively regulate B cell signaling have been shown to be impaired in some SLE patients. These patients have reduced levels of the kinase Lyn in lipid raft microdomains and this reduction is inversely correlated with increased CD45 in lipid rafts. Function and expression of the inhibitory immunoglobulin receptor FcγRIIB is also reduced in Lupus IgM- CD27+ memory cells. Because the relative contribution of different memory and transitional B cell subsets can be abnormal in SLE patients, we believe studies targeted to well defined B cell subsets will be necessary to further our understanding of signaling abnormalities in SLE. Intracellular flow cytometric analysis of signaling is a useful approach to accomplish this goal. PMID:18723129

  16. 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.

  17. Class-switched marginal zone B cells in spleen have relatively low numbers of somatic mutations

    NARCIS (Netherlands)

    Hendricks, Jacobus; Visser, Annie; Dammers, Peter M.; Burgerhof, Johannes G. M.; Bos, Nicolaas A.; Kroese, Frans G. M.

    2011-01-01

    The vast majority of rodent splenic marginal zone (MZ)-B cells are naive IgM(+) cells. A small fraction of these MZ-B cells carry mutated V-genes, and represent IgM(+) memory MZ-B cells. Here we reveal further heterogeneity of B cells with a MZ-B cell phenotype, by providing evidence for the existen

  18. New B-cell Lymphomas in the Setting of a Previous Rare Breast Implant–Associated B-cell Lymphoma

    Science.gov (United States)

    Messer, Alison; Wang, Wei; Duvic, Madeleine

    2016-01-01

    Summary: We present a follow-up of a patient who underwent right-sided subtotal mastectomy and placement of right-sided saline implant in 1968 for a phyllodes tumor and then in 2012 was diagnosed with a rare B-cell type lymphoma of the right breast. In 2015, she was diagnosed with diffuse large B-cell lymphoma involvement of the left breast and left leg and experienced subsequent self-regression of leg lesions without therapy. PMID:27975038

  19. Essential role of MALT1 protease activity in activated B cell-like diffuse large B-cell lymphoma

    OpenAIRE

    Hailfinger, Stephan; Lenz, Georg; Ngo, Vu; Posvitz-Fejfar, Anita; Rebeaud, Fabien; Guzzardi, Montserrat; Penas, Eva-Maria Murga; Dierlamm, Judith; Chan, Wing C.; Staudt, Louis M.; Thome, Margot

    2009-01-01

    A key element for the development of suitable anti-cancer drugs is the identification of cancer-specific enzymatic activities that can be therapeutically targeted. Mucosa-associated lymphoid tissue transformation protein 1 (MALT1) is a proto-oncogene that contributes to tumorigenesis in diffuse large B-cell lymphoma (DLBCL) of the activated B-cell (ABC) subtype, the least curable subtype of DLBCL. Recent data suggest that MALT1 has proteolytic activity, but it is unknown whether this activity...

  20. Cutting Edge: Regulation of TLR4-driven B cell proliferation by RP105 is not B cell-autonomous

    Science.gov (United States)

    Allen, Jessica L.; Flick, Leah M.; Divanovic, Senad; Jackson, Shaun W.; Bram, Richard; Rawlings, David J.; Finkelman, Fred D.; Karp, Christopher L.

    2012-01-01

    Mechanistic understanding of RP105 has been confounded by the fact that this TLR homolog has appeared to have opposing, cell type-specific effects on TLR4 signaling. While RP105 inhibits TLR4-driven signaling in cell lines and myeloid cells, impaired LPS-driven proliferation by B cells from RP105−/− mice has suggested that RP105 facilitates TLR4 signaling in B cells. We show here that modulation of B cell proliferation by RP105 is not a function of B cell-intrinsic expression of RP105, and identify a mechanistic role for dysregulated BAFF expression in the proliferative abnormalities of B cells from RP105−/− mice: serum BAFF levels are elevated in RP105−/− mice, and partial BAFF neutralization rescues aberrant B cell proliferative responses in such mice. These data indicate that RP105 does not have dichotomous effects on TLR4 signaling, and emphasize the need for caution in interpreting the results of global genetic deletion. PMID:22291190

  1. Cutting edge: regulation of TLR4-driven B cell proliferation by RP105 is not B cell autonomous.

    Science.gov (United States)

    Allen, Jessica L; Flick, Leah M; Divanovic, Senad; Jackson, Shaun W; Bram, Richard; Rawlings, David J; Finkelman, Fred D; Karp, Christopher L

    2012-03-01

    Mechanistic understanding of RP105 has been confounded by the fact that this TLR homolog has appeared to have opposing, cell type-specific effects on TLR4 signaling. Although RP105 inhibits TLR4-driven signaling in cell lines and myeloid cells, impaired LPS-driven proliferation by B cells from RP105(-/-) mice has suggested that RP105 facilitates TLR4 signaling in B cells. In this article, we show that modulation of B cell proliferation by RP105 is not a function of B cell-intrinsic expression of RP105, and identify a mechanistic role for dysregulated BAFF expression in the proliferative abnormalities of B cells from RP105(-/-) mice: serum BAFF levels are elevated in RP105(-/-) mice, and partial BAFF neutralization rescues aberrant B cell proliferative responses in such mice. These data indicate that RP105 does not have dichotomous effects on TLR4 signaling and emphasize the need for caution in interpreting the results of global genetic deletion.

  2. 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 (TFH) cells support terminal B-cell differentiation. Human regulatory B (Breg) cells modulate cellular responses, but their control of TFH cell-dependent humoral immune responses is unknown. We sought to assess the role of Breg cells on TFH cell development and function. Human T cells were polyclonally stimulated in the presence of IL-12 and IL-21 to generate TFH 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 TFH 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 TFH cell development. Added to TFH 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 TFH 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 TFH cell maturation, expand follicular regulatory T cells, and inhibit the TFH 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 TFH 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.

  3. Presentation of antigen by B cells subsets. Pt. 1. Lyb-5{sup +} and Lyb-5{sup -} B cells differ in ability to stimulate specific T cells

    Energy Technology Data Exchange (ETDEWEB)

    Zimecki, M. [Polska Akademia Nauk, Wroclaw (Poland). Inst. Immunologii i Terapii Doswiadczalnej; Whiteley, P.J. [Merck and Co., Inc., Rahway, NJ (United States); Pierce, C.W.; Kapp, J.A. [Harrington Cancer Center, Amarillo (United States). Dept. of Cellular and Molecular Immunology

    1994-12-31

    We have examined the antigen presenting cell (APC) function of different B cells. Resident, peritoneal B cells from normal mice were more efficient than splenic B cells in presenting antigen to CD4{sup +} T cell lines. Peritoneal B cells from X-linked immunodeficient (Xid) mice, by contrast, stimulated no detectable responses. Xid splenic B cells were much less efficient APC than normal splenic B cells. B cells from neonatal mice also were very poor APC until the mice were 3 to 4 weeks old. Xid B cells presented antigen to T cell hybridomas as well as normal B cells showing that they process antigen normally. Thus, the defect is most likely in providing secondary signals. The ability of B cells to present antigen efficiency correlates with the percentage of B cells reported to express the Lyb-5 antigen. Anti-Lyb-5 serum and complement abrogated the APC activity of B cells suggesting that Lyb-5{sup +}, but not Lyb-5{sup -} cells are efficient APC. We also found that activated and resting normal splenic B cells, separated by buoyant density, presented antigen equally. Both populations also contained Lyb-5{sup +} B cells although they were a larger fraction of the activated cells. Lyb-5 is now thought to be an activation antigen rather than a differentiation antigen. If this idea is correct, then our data indicate that anti-Lyb-5 more cleanly separates activated and resting B cells than buoyant density techniques. (author). 38 refs, 7 figs, 1 tab.

  4. Safety and Tolerability Study of PCI-32765 in B Cell Lymphoma and Chronic Lymphocytic Leukemia

    Science.gov (United States)

    2017-10-09

    B-cell Chronic Lymphocytic Leukemia; Small Lymphocytic Lymphoma; Diffuse Well-differentiated Lymphocytic Lymphoma; B Cell Lymphoma; Follicular Lymphoma; Mantle Cell Lymphoma; Non-Hodgkin's Lymphoma; Waldenstrom Macroglobulinemia; Burkitt Lymphoma; B-Cell Diffuse Lymphoma

  5. 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...... staining and mRNA were induced by the combination of LPS plus IL-5. LPS+IL-5-treated B cells responded to IL-2 by Ig secretion. This indicates that B cells regulate their responsiveness to IL-2 similarly to T cells, via the combined level of expression of IL-2R beta and IL-2R alpha. The synergy between IL...

  6. Th1 and Th2 help for B cells

    DEFF Research Database (Denmark)

    Poudrier, J; Owens, T

    1995-01-01

    Sustained interaction with Th1 cells has been shown to induce IL-2 responsiveness by murine B cells. This is equivalently dependent on CD40, CD54/ICAM-1 and MHC II ligation, and co-cross-linking of CD54 and MHC II in the presence of IL-5 up-regulates a functional IL-2R on B cells. We now show...... 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...... beta expression following T cell removal, as opposed to enhancement of IL-2R induction or function. The level of contact-induced IL-2R expression on B cells was not itself modified by IL-5. The effects of IL-5 did not overcome the requirement for T contact signals and treatment of B cells with soluble...

  7. [Single B cell monoclonal antibody technologies and applications].

    Science.gov (United States)

    Chi, Xiangyang; Yu, Changming; Chen, Wei

    2012-06-01

    Monoclonal antibodies (mAbs) contribute a lot to the development of numerous fields in life science as a pivotal tool in modern biological research. Development of the PCR methods and maturation of antibody production have made it possible to generate mAbs from single human B cells by single cell RT-PCR with successional cloning and expression in vitro. Compared to traditional monoclonal antibody technologies, single B cell technologies require relatively fewer cells, which are highly efficient in obtaining specific mAbs in a rapid way with preservation of the natural heavy and light chain pairing. With so many advantages, single B cell technologies have been proved to be an attractive approach for retrieval of naive and antigen-experienced antibody repertoires generated in vivo, design of rationale structure-based vaccine, evaluation and development of basic B cell biology concepts in health and autoimmunity, and prevention of infectious diseases by passive immunization and therapy for disorders. Accordingly, this review introduced recent progresses in the single B cell technologies for generating monoclonal antibodies and applications.

  8. Regulation of germinal center B-cell differentiation.

    Science.gov (United States)

    Zhang, Yang; Garcia-Ibanez, Laura; Toellner, Kai-Michael

    2016-03-01

    Germinal centers (GC) are the main sites where antigen-activated B-cell clones expand and undergo immunoglobulin gene hypermutation and selection. Iterations of this process will lead to affinity maturation, replicating Darwinian evolution on the cellular level. GC B-cell selection can lead to four different outcomes: further expansion and evolution, apoptosis (non-selection), or output from the GC with differentiation into memory B cells or plasma cells. T-helper cells in GC have been shown to have a central role in regulating B-cell selection by sensing the density of major histocompatibility complex (MHC):peptide antigen complexes. Antigen is provided on follicular dendritic cells in the form of immune complex. Antibody on these immune complexes regulates antigen accessibility by shielding antigen from B-cell receptor access. Replacement of antibody on immune complexes by antibody generated from GC-derived plasma cell output will gradually reduce the availability of antigen. This antibody feedback can lead to a situation where a slow rise in selection stringency caused by a changing environment leads to directional evolution toward higher affinity antibody.

  9. 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...

  10. Inferring processes underlying B-cell repertoire diversity

    Science.gov (United States)

    Elhanati, Yuval; Sethna, Zachary; Marcou, Quentin; Callan, Curtis G.; Mora, Thierry; Walczak, Aleksandra M.

    2015-01-01

    We quantify the VDJ recombination and somatic hypermutation processes in human B cells using probabilistic inference methods on high-throughput DNA sequence repertoires of human B-cell receptor heavy chains. Our analysis captures the statistical properties of the naive repertoire, first after its initial generation via VDJ recombination and then after selection for functionality. We also infer statistical properties of the somatic hypermutation machinery (exclusive of subsequent effects of selection). Our main results are the following: the B-cell repertoire is substantially more diverse than T-cell repertoires, owing to longer junctional insertions; sequences that pass initial selection are distinguished by having a higher probability of being generated in a VDJ recombination event; somatic hypermutations have a non-uniform distribution along the V gene that is well explained by an independent site model for the sequence context around the hypermutation site. PMID:26194757

  11. Engaging the lysosomal compartment to combat B cell malignancies

    DEFF Research Database (Denmark)

    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......Abs with higher capacity to induce programmed cell death. The so-called type II anti-CD20 mAbs (e.g., tositumomab) that trigger caspase-independent B cell lymphoma cell death in vitro and show superior efficacy as compared with rituximab in eradicating target cells in mouse models are emerging as the next......-targeting drugs in the treatment of B cell malignancies Udgivelsesdato: 2009/8...

  12. 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.

  13. The Roles of Regulatory B Cells in Cancer

    Directory of Open Access Journals (Sweden)

    Yan He

    2014-01-01

    Full Text Available Regulatory B cells (Bregs, a newly described subset of B cells, have been proved to play a suppressive role in immune system. Bregs can inhibit other immune cells through cytokines secretion and antigen presentation, which give them the role in the pathogenesis of autoimmune diseases and cancers. There are no clear criteria to identify Bregs; different markers were used in the different experimental conditions. Massive researches had described the functions of immune cells such as regulatory T cells (Tregs, dendritic cells (DCs, and B cells in the autoimmune disorder diseases and cancers. More and more researches focused on the roles of Bregs and the cytokines such as Interleukin-10 (IL-10 and transforming growth factor beta (TGF-β secreted by Bregs. The aim of this review is to summarize the characteristics of Bregs and the roles of Bregs in cancer.

  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 role of B cells and autoantibodies in neuropsychiatric lupus.

    Science.gov (United States)

    Wen, Jing; Stock, Ariel D; Chalmers, Samantha A; Putterman, Chaim

    2016-09-01

    The central nervous system manifestations of SLE (neuropsychiatric lupus, NPSLE) occur frequently, though are often difficult to diagnose and treat. Symptoms of NPSLE can be quite diverse, including chronic cognitive and emotional manifestations, as well as acute presentations, such as stroke and seizures. Although the pathogenesis of NPSLE has yet to be well characterized, B-cell mediated damage is believed to be an important contributor. B-cells and autoantibodies may traverse the blood brain barrier promoting an inflammatory environment consisting of glia activation, neurodegeneration, and consequent averse behavioral outcomes. This review will evaluate the various suggested roles of B-cells and autoantibodies in NPSLE, as well as therapeutic modalities targeting these pathogenic mediators.

  16. Novel Therapies for Aggressive B-Cell Lymphoma

    Directory of Open Access Journals (Sweden)

    Kenneth A. Foon

    2012-01-01

    Full Text Available Aggressive B-cell lymphoma (BCL comprises a heterogeneous group of malignancies, including diffuse large B-cell lymphoma (DLBCL, Burkitt lymphoma, and mantle cell lymphoma (MCL. DLBCL, with its 3 subtypes, is the most common type of lymphoma. Advances in chemoimmunotherapy have substantially improved disease control. However, depending on the subtype, patients with DLBCL still exhibit substantially different survival rates. In MCL, a mature B-cell lymphoma, the addition of rituximab to conventional chemotherapy regimens has increased response rates, but not survival. Burkitt lymphoma, the most aggressive BCL, is characterized by a high proliferative index and requires more intensive chemotherapy regimens than DLBCL. Hence, there is a need for more effective therapies for all three diseases. Increased understanding of the molecular features of aggressive BCL has led to the development of a range of novel therapies, many of which target the tumor in a tailored manner and are summarized in this paper.

  17. Transcription factors regulating B cell fate in the germinal centre.

    Science.gov (United States)

    Recaldin, T; Fear, D J

    2016-01-01

    Diversification of the antibody repertoire is essential for the normal operation of the vertebrate adaptive immune system. Following antigen encounter, B cells are activated, proliferate rapidly and undergo two diversification events; somatic hypermutation (followed by selection), which enhances the affinity of the antibody for its cognate antigen, and class-switch recombination, which alters the effector functions of the antibody to adapt the response to the challenge faced. B cells must then differentiate into antibody-secreting plasma cells or long-lived memory B cells. These activities take place in specialized immunological environments called germinal centres, usually located in the secondary lymphoid organs. To complete the germinal centre activities successfully, a B cell adopts a transcriptional programme that allows it to migrate to specific sites within the germinal centre, proliferate, modify its DNA recombination and repair pathways, alter its apoptotic potential and finally undergo terminal differentiation. To co-ordinate these processes, B cells employ a number of 'master regulator' transcription factors which mediate wholesale transcriptomic changes. These master transcription factors are mutually antagonistic and form a complex regulatory network to maintain distinct gene expression programs. Within this network, multiple points of positive and negative feedback ensure the expression of the 'master regulators', augmented by a number of 'secondary' factors that reinforce these networks and sense the progress of the immune response. In this review we will discuss the different activities B cells must undertake to mount a successful T cell-dependent immune response and describe how a regulatory network of transcription factors controls these processes.

  18. Regulation of AID, the B-cell genome mutator.

    Science.gov (United States)

    Keim, Celia; Kazadi, David; Rothschild, Gerson; Basu, Uttiya

    2013-01-01

    The mechanisms by which B cells somatically engineer their genomes to generate the vast diversity of antibodies required to challenge the nearly infinite number of antigens that immune systems encounter are of tremendous clinical and academic interest. The DNA cytidine deaminase activation-induced deaminase (AID) catalyzes two of these mechanisms: class switch recombination (CSR) and somatic hypermutation (SHM). Recent discoveries indicate a significant promiscuous targeting of this B-cell mutator enzyme genome-wide. Here we discuss the various regulatory elements that control AID activity and prevent AID from inducing genomic instability and thereby initiating oncogenesis.

  19. Anti-CDR3 Therapy for B-Cell Malignancies

    Science.gov (United States)

    2014-10-01

    AWARD NUMBER: W81XWH-12-1-0548 TITLE: PRINCIPAL INVESTIGATOR: Anti-CDR3 Therapy for B-Cell Malignancies Dr. David Fitzgerald CONTRACTING...REPORT DATE October 2014 2. REPORT TYPE Annual 3. DATES COVERED (From - To) 30 Sep 2013 - 29 Sep 2014 "Anti-CDR3 Therapy for B-Cell Malignancies” 5a...and light chains, into a model antibody 4D5 (see figures 1-5 in the report). The "Tomlinson" human antibody phage library will be used to pan for

  20. EBV-Associated Cancer and Autoimmunity: Searching for Therapies

    Directory of Open Access Journals (Sweden)

    Giovanni Capone

    2015-02-01

    Full Text Available Epstein-Barr virus (EBV infects B-, T-, and NK cells and has been associated not only with a wide range of lymphoid malignancies but also with autoimmune diseases such as lupus erythematosus, rheumatoid arthritis and, in particular, multiple sclerosis. Hence, effective immunotherapeutic approaches to eradicate EBV infection might overthrow cancer and autoimmunity incidence. However, currently no effective anti-EBV immunotherapy is available. Here we use the concept that protein immunogenicity is allocated in rare peptide sequences and search the Epstein-Barr nuclear antigen 1 (EBNA1 sequence for peptides unique to the viral protein and absent in the human host. We report on a set of unique EBV EBNA1 peptides that might be used in designing peptide-based therapies able to specifically hitting the virus or neutralizing pathogenic autoantibodies.

  1. "Primary Immunodeficiencies Inducing EBV-Associated Severe Illnesses "

    Directory of Open Access Journals (Sweden)

    Toshio Miyawaki

    2004-06-01

    Full Text Available Epstein-Barr virus (EBV is a ubiquitous human -herpesvirus that infects about 95% of the adult population. The majority of primary infections occurs in early childhood and is generally subclinical; it can cause infectious mononucleosis (IM, which is usually a self-limiting lymphoproliferative disorder. However, infection of EBV occasionally results in severe, often lethal diseases, which include fatal IM, hemophagocytic syndrome, polyclonal lymphoproliferative disorders, and malignant lymphoma. These severe EBV-related illnesses occur secondary to some primary immunodeficiency diseases showing inefficient immune reaction to EBV. One example is X-linked lymphoproliferative disease (XLP, which is caused by mutations in the SLAM-associated protein (SAP gene. The major clinical manifestations of XLP are fulminant IM, malignant lymphoma and dysgammaglobulinemia. Aplastic anemia, virus-associated hemophagocytic syndrome, and vasculitis have also been reported in XLP. We have developed a flow cytometric method using the anti-SAP monoclonal antibody to search for XLP. This clinically useful assay has successfully been used to identify XLP patients in Japan. In this review, clinical and mutational characteristics of XLP in Japan are mainly described. In addition, it is shown that the similar situations to XLP can occur in other primary immunodeficiencies involving T-cell killing function, such as autoimmune lymphoproliferative syndrome caused by Fas gene mutations or familial hemophagocytic lymphohistiocytosis caused by perforin gene mutations. Finally, the EBV-related terrible disease condition, namely chronic active EBV infection, which is common in Asian areas but its genetic background remains to be elucidated, will be toughed on.

  2. A gammaherpesvirus Bcl-2 ortholog blocks B cell receptor-mediated apoptosis and promotes the survival of developing B cells in vivo.

    Directory of Open Access Journals (Sweden)

    Carrie B Coleman

    2014-02-01

    Full Text Available Gammaherpesviruses such as Epstein-Barr virus (EBV and Kaposi's sarcoma-associated herpesvirus (KSHV, HHV-8 establish lifelong latency in their hosts and are associated with the development of several types of malignancies, including a subset of B cell lymphomas. These viruses are thought to co-opt the process of B cell differentiation to latently infect a fraction of circulating memory B cells, resulting in the establishment of a stable latency setpoint. However, little is known about how this infected memory B cell compartment is maintained throughout the life of the host. We have previously demonstrated that immature and transitional B cells are long-term latency reservoirs for murine gammaherpesvirus 68 (MHV68, suggesting that infection of developing B cells contributes to the maintenance of lifelong latency. During hematopoiesis, immature and transitional B cells are subject to B cell receptor (BCR-mediated negative selection, which results in the clonal deletion of autoreactive B cells. Interestingly, numerous gammaherpesviruses encode homologs of the anti-apoptotic protein Bcl-2, suggesting that virus inhibition of apoptosis could subvert clonal deletion. To test this, we quantified latency establishment in mice inoculated with MHV68 vBcl-2 mutants. vBcl-2 mutant viruses displayed a marked decrease in the frequency of immature and transitional B cells harboring viral genome, but this attenuation could be rescued by increased host Bcl-2 expression. Conversely, vBcl-2 mutant virus latency in early B cells and mature B cells, which are not targets of negative selection, was remarkably similar to wild-type virus. Finally, in vivo depletion of developing B cells during chronic infection resulted in decreased mature B cell latency, demonstrating a key role for developing B cells in the maintenance of lifelong latency. Collectively, these findings support a model in which gammaherpesvirus latency in circulating mature B cells is sustained in

  3. Primary B-cell deficiencies reveal a link between human IL-17-producing CD4 T-cell homeostasis and B-cell differentiation.

    Directory of Open Access Journals (Sweden)

    Rita R Barbosa

    Full Text Available IL-17 is a pro-inflammatory cytokine implicated in autoimmune and inflammatory conditions. The development/survival of IL-17-producing CD4 T cells (Th17 share critical cues with B-cell differentiation and the circulating follicular T helper subset was recently shown to be enriched in Th17 cells able to help B-cell differentiation. We investigated a putative link between Th17-cell homeostasis and B cells by studying the Th17-cell compartment in primary B-cell immunodeficiencies. Common Variable Immunodeficiency Disorders (CVID, defined by defects in B-cell differentiation into plasma and memory B cells, are frequently associated with autoimmune and inflammatory manifestations but we found no relationship between these and Th17-cell frequency. In fact, CVID patients showed a decrease in Th17-cell frequency in parallel with the expansion of activated non-differentiated B cells (CD21(lowCD38(low. Moreover, Congenital Agammaglobulinemia patients, lacking B cells due to impaired early B-cell development, had a severe reduction of circulating Th17 cells. Finally, we found a direct correlation in healthy individuals between circulating Th17-cell frequency and both switched-memory B cells and serum BAFF levels, a crucial cytokine for B-cell survival. Overall, our data support a relationship between Th17-cell homeostasis and B-cell maturation, with implications for the understanding of the pathogenesis of inflammatory/autoimmune diseases and the physiology of B-cell depleting therapies.

  4. Surrogate light chain is required for central and peripheral B-cell tolerance and inhibits anti-DNA antibody production by marginal zone B cells.

    Science.gov (United States)

    Ren, Weicheng; Grimsholm, Ola; Bernardi, Angelina I; Höök, Nina; Stern, Anna; Cavallini, Nicola; Mårtensson, Inga-Lill

    2015-04-01

    Selection of the primary antibody repertoire takes place in pro-/pre-B cells, and subsequently in immature and transitional B cells. At the first checkpoint, μ heavy (μH) chains assemble with surrogate light (SL) chain into a precursor B-cell receptor. In mice lacking SL chain, μH chain selection is impaired, and serum autoantibody levels are elevated. However, whether the development of autoantibody-producing cells is due to an inability of the resultant B-cell receptors to induce central and/or peripheral B-cell tolerance or other factors is unknown. Here, we show that receptor editing is defective, and that a higher proportion of BM immature B cells are prone to undergoing apoptosis. Furthermore, transitional B cells are also more prone to undergoing apoptosis, with a stronger selection pressure to enter the follicular B-cell pool. Those that enter the marginal zone (MZ) B-cell pool escape selection and survive, possibly due to the B-lymphopenia and elevated levels of B-cell activating factor. Moreover, the MZ B cells are responsible for the elevated IgM anti-dsDNA antibody levels detected in these mice. Thus, the SL chain is required for central and peripheral B-cell tolerance and inhibits anti-DNA antibody production by MZ B cells.

  5. Primary central nervous system B cell lymphoma with features intermediate between diffuse large B cell lymphoma and Burkitt lymphoma.

    Science.gov (United States)

    Jiang, Liuyan; Li, Zhimin; Finn, Laura E; Personnet, David A; Edenfield, Brandy; Foran, James M; Jaeckle, Kurt A; Reimer, Ronald; Menke, David M; Ketterling, Rhett P; Tun, Han W

    2012-01-01

    B cell lymphoma with features intermediate between diffuse large B cell lymphoma and Burkitt lymphoma (DLBCL/BL) is a new lymphoma entity which is recognized in the current World Health Organization (WHO) classification (2008). We report a case of a primary central nervous system lymphoma (PCNSL) with findings consistent with DLBCL/BL. It is characterized by a very aggressive clinical course, and a widespread multifocal involvement of the CNS. Our case shows that a DLBCL/BL can manifest in the CNS alone without any systemic involvement.

  6. CD20(+) B Cell Depletion Alters T Cell Homing

    NARCIS (Netherlands)

    Kap, Yolanda S.; van Driel, Nikki; Laman, Jon D.; Tak, Paul P.; 't Hart, Bert A.

    2014-01-01

    Depleting mAbs against the pan B cell marker CD20 are remarkably effective in the treatment of autoimmune-mediated inflammatory disorders, but the underlying mechanisms are poorly defined. The primary objective of this study was to find a mechanistic explanation for the remarkable clinical effect of

  7. 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...

  8. Cord blood transplants for SCID: better B-cell engraftment?

    Science.gov (United States)

    Chan, Wan-Yin; Roberts, Robert Lloyd; Moore, Theodore B; Stiehm, E Richard

    2013-01-01

    Hematopoietic stem-cell transplantation is the treatment of choice for severe combined immunodeficiency (SCID). Despite successful T-cell engraftment in transplanted patients, B-cell function is not always achieved; up to 58% of patients require immunoglobulin therapy after receiving haploidentical transplants. We report 2 half-sibling males with X-linked γ-chain SCID treated with different sources of stem cells. Sibling 1 was transplanted with T-cell-depleted haploidentical maternal bone marrow and sibling 2 was transplanted with 7/8 human leukocyte antigen-matched unrelated umbilical cord blood. Both patients received pretransplant conditioning and posttransplant graft-versus-host-disease prophylaxis. B-cell engraftment and function was achieved in sibling 1 but not in sibling 2. This disparate result is consistent with a review of 19 other SCID children who received cord blood transplants. B-cell function, as indicated by no need for immunoglobulin therapy, was restored in 42% of patients given haploidentical transplants and in 68% of patients given matched unrelated donor transplants compared with 80% of patients given cord blood transplants. Cord blood is an alternative source of stem cells for transplantation in children with SCID and has a higher likelihood of B-cell reconstitution.

  9. Selecting B cells and plasma cells to memory

    OpenAIRE

    2005-01-01

    Humoral immunity appears to be based on immunological memory provided by memory plasma cells, which secrete protective antibodies, and memory B cells, which react to antigen challenge by differentiating into plasma cells. How these differentiation pathways relate to each other, how cells are selected into these memory populations, and how these populations are maintained remains enigmatic.

  10. Anthropometrics and Prognosis in Diffuse Large B-Cell Lymphoma

    DEFF Research Database (Denmark)

    Bendtsen, Mette Dahl; Munksgaard, Peter Svenssen; Severinsen, Marianne Tang;

    2016-01-01

    OBJECTIVE: The impact of body mass index (BMI) and body surface area (BSA) on survival in diffuse large B-cell lymphoma (DLBCL) is controversial. Recent studies show superior outcomes for overweight and obese patients. PATIENTS AND METHODS: 653 R-CHOP(-like) treated DLBCL patients were included...

  11. Diffuse Large B Cell Lymphoma Mimicking Granulomatosis with Polyangiitis

    Science.gov (United States)

    Horowitz, Netanel; Ben-Itzhak, Ofer; Braun-Moscovici, Yolanda

    2016-01-01

    In a patient with systemic multiorgan disease with overlapping features, the differential diagnosis included infectious diseases, malignancies, and systemic autoimmune or inflammatory diseases. We present an unusual case of a young male with B cell lymphoma who presented with symptoms mimicking systemic vasculitis and review the existing literature. PMID:27293945

  12. Btk at the Pre-B Cell Receptor Checkpoint

    NARCIS (Netherlands)

    S. Middendorp

    2004-01-01

    textabstractSignalling from the BCR or its immature form, the pre-BCR, was shown to be crucial for B cell development. Gene-targeted mice have defined differential roles of components of the (pre-) BCR complex or its downstream signalling pathways. One of the proteins involved in (pre-) BCR signa

  13. 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.

  14. 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...

  15. Signals that drive T-bet expression in B cells.

    Science.gov (United States)

    Myles, Arpita; Gearhart, Patricia J; Cancro, Michael P

    2017-09-11

    Transcription factors regulate various developmental and functional aspects of B cells. T-bet is a recently appreciated transcription factor associated with "Age-associated B cells" or ABCs, the development of autoimmunity, and viral infections. T-bet expression is favored by nucleic acid-containing antigens and immune complexes and is regulated by interplay between various cytokines, notably, the TFH cytokines IL-21, IL-4 and IFNγ. Adaptive signals by themselves cannot upregulate T-bet; however, they have a synergistic effect on induction of T-bet by innate receptors. The functional role of T-bet+ B cells is unclear, although it is known that T-bet promotes class switching to IgG2a/c. It is likely T-bet serves dichotomous roles in B cells, promoting pathogenic autoreactive antibodies on one hand but mediating microbial immunity on the other, making it a target of interest in both therapeutic and prophylactic settings. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Diffuse Large B Cell Lymphoma Mimicking Granulomatosis with Polyangiitis

    Directory of Open Access Journals (Sweden)

    Mohammad E. Naffaa

    2016-01-01

    Full Text Available In a patient with systemic multiorgan disease with overlapping features, the differential diagnosis included infectious diseases, malignancies, and systemic autoimmune or inflammatory diseases. We present an unusual case of a young male with B cell lymphoma who presented with symptoms mimicking systemic vasculitis and review the existing literature.

  17. Presentation of antigen by B cells subsets. Pt. 2. The role of CD5 B cells in the presentation of antigen to antigen-specific T cells

    Energy Technology Data Exchange (ETDEWEB)

    Zimecki, Michal [Polish Academy of Sciences, Wroclaw (Poland). Institute of Immunology and Experimental Therapy; Kapp, Judith A. [Emory Univ., Atlanta, GA (United States). School of Medicine

    1994-12-31

    We demonstrate that peritoneal B cells have a much higher ability to present antigen to antigen-specific T cell lines splenic B cells. Presentation of antigen by B cells is abrogated or drastically reduced after removal of Lyb-5{sup +} cells from the population of splenic or peritoneal B cells. Peritoneal B cells, precultured for 7 days prior to the antigen presentation assay, retain their antigen presenting cell (APC) function. Enrichment for CD5{sup +} cells in the peritoneal B cell population results in a more effective antigen presentation. Lastly, stimulation of B cells via CD5 antigen, by treatment of cells with anti-CD5 antibodies or cross-linking of CD5 receptors, enhances APC function of these cells. The results indicate, both indirectly and directly, that CD5{sup +} B cells play a predominant role in the presentation of conventional antigens to antigen-specific T cells. (author). 30 refs, 6 tabs.

  18. Inducible resistance to Fas—mediated apoptosis in B cells

    Institute of Scientific and Technical Information of China (English)

    ROTHSTEINTHOMASL

    2000-01-01

    Apoptosis produced in B cells through Fas(APO-1,CD95) triggering is regulated by signals derived from other surface receptors:CD40 engagement produces upregulation of Fas expression and marked susceptibility to Fas-induced cell death,whereas antigen receptor engagement,or IL-4R engagement,inhibits Fas killing and in so doing induces a state of Fas-resistance,even in otherwise sensitive,CD40-stimulated targets.Surface immunoglobulin and IL-4R utilize at least partially distinct path ways to produce Fas-resistance that differentially depend on PKC and STAT6,respectively.Further,surface immunoglobulin signaling for inducible Fas-resistance bypasses Btk,requires NF-κB,and entails new macromolecular synthesis.Terminal effectors of B cell Fas-resistance include the known anti-apoptotic gene products,Bcl-XL and FLIP,and a novel anti-apoptotic gene that encodes FAIM (Fas Apoptosis Inhibitory Molecule).faim was identified by differential display and exists in two alternatively spliced forms;faim-S is broadly expressed,but faim-L expression is tissue-specific.The FAIM sequence is highly evolu tionarily conserved,suggesting an important role for this molecule throughout phylogeny.Inducible resistance to Fas killing is hypothesized to protect foreign antigen-specific B cells during potentially hazardous interactions with FasL-bearing T cells,whereas autoreactive B cells fail to become Fas-resistant and are deleted via Fas-dependent cytotoxicity.Inadvertent or aberrant acquisition of Fas-resistance may permit autoreactive B cells to escape Fas deletion,and malignant lymphocytes to impede anti-tumor immunity.

  19. Inducible resistance to Fas-mediated apoptosis in B cells

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Apoptosis produced in B cells through Fas (APO-1, CD95) triggering is regulated by signals derived from other surface receptors: CD40 engagement produces upregulation of Fas expression and marked susceptibility to Fas-induced cell death, whereas antigen receptor engagement, or IL-4R engagement, inhibits Fas killing and in so doing induces a state of Fas-resistance, even in otherwise sensitive, CD40-stimulated targets. Surface immunoglobulin and IL-4R utilize at least partially distinct pathways to produce Fas-resistance that differentially depend on PKC and STAT6, respectively. Further, surface immunoglobulin signaling for inducible Fas-resistance bypasses Btk, requires NF-кB, and entails new macromolecular synthesis. Terminal effectors of B cell Fas-resistance include the known anti-apoptotic gene products, Bcl-xL and FLIP, and a novel anti-apoptotic gene that encodes FAIM (Fas Apoptosis Inhibitory Molecule). faim was identified by differential display and exists in two alternatively spliced forms; faim-S is broadly expressed, but faim-L expression is tissue-specific. The FAIM sequence is highly evolutionarily conserved, suggesting an important role for this molecule throughout phylogeny. Inducible resistance to Fas killing is hypothesized to protect foreign antigen-specific B cells during potentially hazardous interactions with FasL-bearing T cells, whereas autoreactive B cells fail to become Fas-resistant and are deleted via Fas-dependent cytotoxicity. Inadvertent or aberrant acquisition of Fas-resistance may permit autoreactive B cells to escape Fas deletion, and malignant lymphocytes to impede anti-tumor immunity.

  20. B cell autophagy mediates TLR7-dependent autoimmunity and inflammation.

    Science.gov (United States)

    Weindel, Chi G; Richey, Lauren J; Bolland, Silvia; Mehta, Abhiruchi J; Kearney, John F; Huber, Brigitte T

    2015-01-01

    Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disease, defined by loss of B cell self-tolerance that results in production of antinuclear antibodies (ANA) and chronic inflammation. While the initiating events in lupus development are not well defined, overexpression of the RNA-recognizing toll-like receptor (TLR)7 has been linked to SLE in humans and mice. We postulated that autophagy plays an essential role in TLR7 activation of B cells for the induction of SLE by delivering RNA ligands to the endosomes, where this innate immune receptor resides. To test this hypothesis, we compared SLE development in Tlr7 transgenic (Tg) mice with or without B cell-specific ablation of autophagy (Cd19-Cre Atg5(f/f)). We observed that in the absence of B cell autophagy the 2 hallmarks of SLE, ANA and inflammation, were eliminated, thus curing these mice of lupus. This was also evident in the significantly extended survival of the autophagy-deficient mice compared to Tlr7.1 Tg mice. Furthermore, glomerulonephritis was ameliorated, and the serum levels of inflammatory cytokines in the knockout (KO) mice were indistinguishable from those of control mice. These data provide direct evidence that B cells require TLR7-dependent priming through an autophagy-dependent mechanism before autoimmunity is induced, thereafter involving many cell types. Surprisingly, hyper-IgM production persisted in Tlr7.1 Tg mice in the absence of autophagy, likely involving a different activation pathway than the production of autoantibodies. Furthermore, these mice still presented with anemia, but responded with a striking increase in extramedullary hematopoiesis (EMH), possibly due to the absence of pro-inflammatory cytokines.

  1. 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...

  2. Cellular maturation defects in Bruton's tyrosine kinase-deficient immature B cells are amplified by premature B cell receptor expression and reduced by receptor editing

    NARCIS (Netherlands)

    S. Middendorp; R.W. Hendriks (Rudi)

    2004-01-01

    textabstractIn the mouse, Bruton's tyrosine kinase (Btk) is essential for efficient developmental progression of CD43(+)CD2(-) large cycling into CD43(-)CD2(+) small resting pre-B cells in the bone marrow and of IgM(high) transitional type 2 B cells into IgM(low) mature B cells in

  3. Cellular maturation defects in Bruton's tyrosine kinase-deficient immature B cells are amplified by premature B cell receptor expression and reduced by receptor editing

    NARCIS (Netherlands)

    S. Middendorp; R.W. Hendriks (Rudi)

    2004-01-01

    textabstractIn the mouse, Bruton's tyrosine kinase (Btk) is essential for efficient developmental progression of CD43(+)CD2(-) large cycling into CD43(-)CD2(+) small resting pre-B cells in the bone marrow and of IgM(high) transitional type 2 B cells into IgM(low) mature B cells in

  4. Monoclonal paraprotein influences baseline B-cell repertoire diversity and perturbates influenza vaccination-induced B-cell response

    NARCIS (Netherlands)

    Tete, Sarah M.; Kipling, David; Westra, Johanna; de Haan, Aalzen; Bijl, Marc; Dunn-Walters, Deborah K.; Sahota, Surinder S.; Bos, Nicolaas A.

    2015-01-01

    Monoclonal gammopathy of undetermined significance (MGUS) arises from a clonal expansion of plasma cells in the bone marrow, secreting monoclonal (M) paraprotein. It is associated with increased susceptibility to infections, which may reflect altered B-cell repertoire. To investigate this, we examin

  5. Monoclonal paraprotein influences baseline B-cell repertoire diversity and perturbates influenza vaccination-induced B-cell response

    NARCIS (Netherlands)

    Tete, Sarah M.; Kipling, David; Westra, Johanna; de Haan, Aalzen; Bijl, Marc; Dunn-Walters, Deborah K.; Sahota, Surinder S.; Bos, Nicolaas A.

    2015-01-01

    Monoclonal gammopathy of undetermined significance (MGUS) arises from a clonal expansion of plasma cells in the bone marrow, secreting monoclonal (M) paraprotein. It is associated with increased susceptibility to infections, which may reflect altered B-cell repertoire. To investigate this, we examin

  6. Clinical and In Vitro Studies on Impact of High-Dose Etoposide Pharmacokinetics Prior Allogeneic Hematopoietic Stem Cell Transplantation for Childhood Acute Lymphoblastic Leukemia on the Risk of Post-Transplant Leukemia Relapse.

    Science.gov (United States)

    Sobiak, Joanna; Kazimierczak, Urszula; Kowalczyk, Dariusz W; Chrzanowska, Maria; Styczyński, Jan; Wysocki, Mariusz; Szpecht, Dawid; Wachowiak, Jacek

    2015-10-01

    The impact of etoposide (VP-16) plasma concentrations on the day of allogeneic hematopoietic stem cell transplantation (allo-HSCT) on leukemia-free survival in children with acute lymphoblastic leukemia (ALL) was studied. In addition, the in vitro effects of VP-16 on the lymphocytes proliferation, cytotoxic activity and on Th1/Th2 cytokine responses were assessed. In 31 children undergoing allo-HSCT, VP-16 plasma concentrations were determined up to 120 h after the infusion using the HPLC-UV method. For mentioned in vitro studies, VP-16 plasma concentrations observed on allo-HSCT day were used. In 84 % of children, VP-16 plasma concentrations (0.1-1.5 μg/mL) were quantifiable 72 h after the end of the drug infusion, i.e. when allo-HSCT should be performed. In 20 (65 %) children allo-HSCT was performed 4 days after the end of the drug infusion, and VP-16 was still detectable (0.1-0.9 μg/mL) in plasma of 12 (39 %) of them. Post-transplant ALL relapse occurred in four children, in all of them VP-16 was detectable in plasma (0.1-0.8 μg/mL) on allo-HSCT day, while there was no relapse in children with undetectable VP-16. In in vitro studies, VP-16 demonstrated impact on the proliferation activity of stimulated lymphocytes depending on its concentration and exposition time. The presence of VP-16 in plasma on allo-HSCT day may demonstrate an adverse effect on graft-versus-leukemia (GvL) reaction and increase the risk of post-transplant ALL relapse. Therefore, if 72 h after VP-16 administration its plasma concentration is still above 0.1 μg/mL then the postponement of transplantation for next 24 h should be considered to protect GvL effector cells from transplant material.

  7. The B cell antigen receptor and overexpression of MYC can cooperate in the genesis of B cell lymphomas.

    Directory of Open Access Journals (Sweden)

    Yosef Refaeli

    2008-06-01

    Full Text Available A variety of circumstantial evidence from humans has implicated the B cell antigen receptor (BCR in the genesis of B cell lymphomas. We generated mouse models designed to test this possibility directly, and we found that both the constitutive and antigen-stimulated state of a clonal BCR affected the rate and outcome of lymphomagenesis initiated by the proto-oncogene MYC. The tumors that arose in the presence of constitutive BCR differed from those initiated by MYC alone and resembled chronic B cell lymphocytic leukemia/lymphoma (B-CLL, whereas those that arose in response to antigen stimulation resembled large B-cell lymphomas, particularly Burkitt lymphoma (BL. We linked the genesis of the BL-like tumors to antigen stimulus in three ways. First, in reconstruction experiments, stimulation of B cells by an autoantigen in the presence of overexpressed MYC gave rise to BL-like tumors that were, in turn, dependent on both MYC and the antigen for survival and proliferation. Second, genetic disruption of the pathway that mediates signaling from the BCR promptly killed cells of the BL-like tumors as well as the tumors resembling B-CLL. And third, growth of the murine BL could be inhibited by any of three distinctive immunosuppressants, in accord with the dependence of the tumors on antigen-induced signaling. Together, our results provide direct evidence that antigenic stimulation can participate in lymphomagenesis, point to a potential role for the constitutive BCR as well, and sustain the view that the constitutive BCR gives rise to signals different from those elicited by antigen. The mouse models described here should be useful in exploring further the pathogenesis of lymphomas, and in preclinical testing of new therapeutics.

  8. Germinal Center B-Cell-Associated Nuclear Protein (GANP) Involved in RNA Metabolism for B Cell Maturation.

    Science.gov (United States)

    Sakaguchi, N; Maeda, K

    2016-01-01

    Germinal center B-cell-associated nuclear protein (GANP) is upregulated in germinal center B cells against T-cell-dependent antigens in mice and humans. In mice, GANP depletion in B cells impairs antibody affinity maturation. Conversely, its transgenic overexpression augments the generation of high-affinity antigen-specific B cells. GANP associates with AID in the cytoplasm, shepherds AID into the nucleus, and augments its access to the rearranged immunoglobulin (Ig) variable (V) region of the genome in B cells, thereby precipitating the somatic hypermutation of V region genes. GANP is also upregulated in human CD4(+) T cells and is associated with APOBEC3G (A3G). GANP interacts with A3G and escorts it to the virion cores to potentiate its antiretroviral activity by inactivating HIV-1 genomic cDNA. Thus, GANP is characterized as a cofactor associated with AID/APOBEC cytidine deaminase family molecules in generating diversity of the IgV region of the genome and genetic alterations of exogenously introduced viral targets. GANP, encoded by human chromosome 21, as well as its mouse equivalent on chromosome 10, contains a region homologous to Saccharomyces Sac3 that was characterized as a component of the transcription/export 2 (TREX-2) complex and was predicted to be involved in RNA export and metabolism in mammalian cells. The metabolism of RNA during its maturation, from the transcription site at the chromosome within the nucleus to the cytoplasmic translation apparatus, needs to be elaborated with regard to acquired and innate immunity. In this review, we summarize the current knowledge on GANP as a component of TREX-2 in mammalian cells.

  9. Post-transplant donor-specific antibody production and graft outcome in kidney transplantation: results of sixteen-year monitoring by flow cytometry.

    Science.gov (United States)

    Piazza, Antonina; Poggi, Elvira; Ozzella, Giuseppina; Borrelli, Laura; Scornajenghi, Alessandra; Iaria, Giuseppe; Tisone, Giuseppe; Adorno, Domenico

    2006-01-01

    Our data show that monitoring by sensitive flow cytometric techniques of the de novo production of anti-HLA antibodies in patients receiving kidney transplantation is a useful and noninvasive tool to identify the onset of an immune response towards the graft before any clinical manifestation of antibody-mediated graft injury. Consequently prospective posttransplant monitoring of anti-HLA donor-directed antibodies may offer the chance to realize an effective clinical intervention in order to prevent graft dysfunction and to prolong graft survival. The long follow-up period of the study allowed us to demonstrate a very low graft survival rate in patients who developed donor-specific HLA antibodies in comparison with patients who did not have antibodies, thus confirming the "humoral theory of transplantation". The posttransplant production of anti-HLA antibodies can predict not only graft failure but also chronic dysfunction of the graft. Moreover, our findings suggest that graft survival is influenced by the epitope- and locus-specificity of anti-HLA donor-directed antibodies. The interval between antibody appearance and loss of graft function was short in some patients but reached several years in others. Moreover, some patients showed consistent production of antibodies for many years and an uneventful clinical status. These findings suggest a mechanism of graft "accommodation" or the production of "harmless" antibodies. Immunosuppressive drug combinations able to inhibit T and B cell activation are useful tools to prevent the humoral immune response against graft and consequently to prolong graft survival.

  10. Ibrutinib Before and After Stem Cell Transplant in Treating Patients With Relapsed or Refractory Diffuse Large B-cell Lymphoma

    Science.gov (United States)

    2016-10-20

    Activated B-Cell-Like Diffuse Large B-Cell Lymphoma; B-Cell Lymphoma, Unclassifiable, With Features Intermediate Between Diffuse Large B-Cell Lymphoma and Burkitt Lymphoma; Recurrent Diffuse Large B-Cell Lymphoma; Refractory Diffuse Large B-Cell Lymphoma

  11. Cutaneous B cell lymphomas: Report of two interesting cases

    Directory of Open Access Journals (Sweden)

    Ravichandran Gurumurthy

    2015-01-01

    Full Text Available Cutaneous B cell lymphomas can arise primarily from the skin or may occur due to secondary spread from nodal lymphomas. Primary lymphomas are confined to the skin without systemic spread and they differ from secondary lymphomas in their clinical behavior, treatment and prognosis. Cutaneous lymphomas being relatively rare, lack of precise definition and understanding of their clinical behavior diseases leads to pitfalls in the diagnosis. We report two cases of cutaneous B cell lymphomas who presented with fever of unknown origin initially and later found to have skin lesions. Hence, skin can be a potential diagnostic clue in the evaluation of patients with fever of unknown origin. The distinctions between the primary and the secondary lymphomas become important in choosing the treatment and assessing the prognosis.

  12. Plasma-cell-predominant B-cell pseudolymphoma.

    Science.gov (United States)

    Nervi, Stephen J; Schwartz, R A

    2008-10-15

    A 46-year-old woman with no history of foreign travel presented to the New Jersey Medical School Dermatology Clinic in July, 2007, with pruritic ulcerating facial masses that had been present since October, 2006. Clinical and histopathologic findings were most consistent with a diagnosis of cutaneous plasma cell predominant B cell pseudolymphoma. An extensive search using special stains for an etiologic organism was negative. The term cutaneous pseudolymphoma has been coined to describe the accumulation of either T or B cell lymphocytes in the skin that is caused by a nonmalignant stimulus and encompasses several different terms depending on etiology. In cases of cutaneous pseudolymphoma where a cause is identified, treatment entails removing the underlying causative agent. Idiopathic cases tend to be recalcitrant to treatment.

  13. Deletion of genes encoding PU.1 and Spi-B in B cells impairs differentiation and induces pre-B cell acute lymphoblastic leukemia.

    Science.gov (United States)

    Sokalski, Kristen M; Li, Stephen K H; Welch, Ian; Cadieux-Pitre, Heather-Anne T; Gruca, Marek R; DeKoter, Rodney P

    2011-09-01

    The E26 transformation-specific (Ets) transcription factor PU.1 is required to generate lymphoid progenitor cells from hematopoietic stem cells, but it is not required to generate B cells from committed B-cell lineage progenitors. We hypothesized that PU.1 function in B-cell differentiation is complemented by the related Ets transcription factor Spi-B. To test this hypothesis, mice were generated lacking both PU.1 and Spi-B in the B-cell lineage. Unlike mice lacking PU.1 or Spi-B, mice deficient in both PU.1 and Spi-B in the B-cell lineage had reduced frequencies of B cells as well as impaired B-cell differentiation. Strikingly, all PU.1 and Spi-B-deficient mice developed pre-B cell acute lymphoblastic leukemia before 30 weeks of age. Pre-B cells accumulated in the thymus resulting in massive thymic enlargement and dyspnea. These findings demonstrate that PU.1 and Spi-B are essential transcriptional regulators of B-cell differentiation as well as novel tumor suppressors in the B-cell lineage.

  14. [Significance of regulatory B cells in nosogenesis of immune thrombocytopenia].

    Science.gov (United States)

    Li, Xin; Wang, Fang; Ding, Kai Yang; Dai, Lan

    2014-04-01

    This study was aimed to investigate the role of regulatory B cells (Breg) in pathogenesis of immune thrombocytopenia (ITP) and its clinical significance. A total of 35 ITP patients and 20 normal controls were enrolled in this study. The expression of CD19(+)CD24(hi)CD38(hi) B cells was detected by flow cytometry and the expression of IL-10 mRNA and TGF-β1 mRNA was assayed by RT-PCR. The results indicated that the expression level of CD19(+)CD24(hi)CD38(hi) B cells in peripheral blood of newly diagnosed ITP patients was obviously lower than that in normal controls (P < 0.05); the expression level of CD19(+)CD24(hi)CD38(hi) B cells in ITP patients with increased platelet count after treatment was higher than that before treatment (P < 0.05); the expression level of IL-10 mRNA in newly diagnosed ITP patients was significantly lower than that the in normal controls (P < 0.05), the expression level of TGF-β1 mRNA in newly diagnosed ITP patients increases as compared with normal controls (P < 0.05), after treatment with DXM the expression of IL-10 mRNA was enhanced, the expression of TGF-β1 mRNA was reduced as compared with expression level before treatment (P < 0.05). It is concluded that the Breg cells may play an important role in the pathogenesis of ITP via humoral immunity and its regulation of T lymphocytes.

  15. B-cell Prolymphocytic Leukemia in a Young Male

    Directory of Open Access Journals (Sweden)

    Kirana Pailoor

    2011-07-01

    Full Text Available B-cell prolymphocytic leukemia [B-PLL] is a neoplasm of B prolymphocytes affecting the peripheral blood, bone marrow and spleen. The principal disease characteristics are massive splenomegaly with absent or minimal peripheral lymphadenopathy and a rapidly rising lymphocyte count. Here, we report a case of B-PLL in a 42 year old male who had come for routine health check up.

  16. Primary marginal zone B-cell lymphoma of appendix

    Directory of Open Access Journals (Sweden)

    Radha S

    2008-07-01

    Full Text Available Primary lymphomas of appendix are extremely rare tumors. The first case of primary lymphoma of appendix was reported by Warren in the year 1898. Incidence of primary lymphoma of appendix is 0.015% of all gastrointestinal lymphomas. This is a report of primary marginal zone B-cell lymphoma of appendix which presented as appendicular mass. As some cases are incidentally discovered, this case emphasizes that histological examination of all appendicectomy specimens is mandatory.

  17. Lenalidomide in Diffuse Large B-Cell Lymphoma

    OpenAIRE

    Catherine Thieblemont; Marie-Hélène Delfau-Larue; Bertrand Coiffier

    2012-01-01

    Diffuse large B-cell lymphoma (DLBCL) is the most common form of non-Hodgkin's lymphoma (NHL) in adults. Even if the natural history of DLBCL has been improved with the advent of immunochemotherapy, the survival results obtained with current treatment options clearly indicate that new agents or novel approaches are needed. Lenalidomide (Revlimid, Celgene Corporation, Summit, NJ, USA), an analogue of thalidomide, is an immunomodulatory drug with pleiotropic mechanisms of action potentially add...

  18. Lenalidomide in Diffuse Large B-Cell Lymphomas

    Directory of Open Access Journals (Sweden)

    Annalisa Chiappella

    2012-01-01

    Full Text Available Diffuse Large B-cell Lymphomas (DLBCL are the most frequent Non-Hodgkin Lymphomas (NHL. The addition of Rituximab to the standard chemotherapy CHOP improved the outcome in this patients, but so far 40% of patients experienced relapse or progressive disease. Lenalidomide, an immunomodulatory agent, had direct tumoricidal and antiangiogenetic actions on tumor cells and was able to modulate tumor-cell microenvironment, with the restoration of impaired T-cell activity and the formation of immuno-synapsis. Based on these actions, lenalidomide represented an active drug on aggressive relapsed NHL. In this review, the most relevant clinical trials for the use of lenalidomide in DLBCL were reported. Monotherapy with lenalidomide showed an activity in term of overall response rate, with acceptable hematological and extrahematological toxicities in relapsed/refractory aggressive NHL. The role of lenalidomide as salvage therapy in both cell of origin patterns in DLBCL (germinal center B-cell/activated B-cell was reported in preliminary data. Preliminary data regarding the role of lenalidomide in addition to chemoimmunotherapy (R-CHOP in first line clinical trials were discussed; data of safety, feasibility and efficacy were promising.

  19. Small B cell lymphocytic lymphoma presenting as obstructive sleep apnea

    Directory of Open Access Journals (Sweden)

    Chang Weng-Cheng

    2004-07-01

    Full Text Available Abstract Background Most lymphomas that involve the tonsil are large B cell lymphomas. Large B-cell lymphoma is a high grade malignancy which progresses rapidly. Tonsillar lymphoma usually presents as either a unilaterally enlarged palatine tonsil or as an ulcerative and fungating lesion over the tonsillar area. Small lymphocytic lymphomas (SLL of the Waldeyer's ring are uncommon. Case presentation We report a 41-year-old male who presented with a ten-year history of snoring. Physical examination revealed smooth bilateral symmetrically enlarged tonsils without abnormal surface change or cervical lymphadenopathy. Palatal redundancy and a narrowed oropharyngeal airway were also noted. The respiratory disturbance index (RDI was 66 per hour, and severe obstruction sleep apnea (OSA was suspected. No B symptoms, sore throat, odynophagia or dysphagia was found. We performed uvulopalatopharyngoplasty (UPPP and pathological examination revealed incidental small B-cell lymphocytic lymphoma (SLL. Conclusion It is uncommon for lymphoma to initially present as OSA. SLL is an indolent malignancy and is not easy to detect in the early stage. We conclude that SLL may be a contributing factor of OSA in the present case.

  20. Pancreatic A and B cell hyperfunction in the Mendenhall syndrome.

    Science.gov (United States)

    Serrano Ríos, M; de la Viña, S; Carbó, M E; Nash, R E; Barrio, R; Heding, L G

    1983-07-01

    A 16-year-old boy with persistent hyperglycaemia (approximately 16 mmol/l in the fasting state) and acanthosis nigricans had insulin resistance and received daily up to 2800 U of short-acting, soluble, highly purified porcine insulin. The number and affinity of insulin receptors were markedly decreased. No significant insulin binding to IgG could be detected. Immunoreactive insulin varied between 1344 and 2400 mU/l. Endogenous insulin secretion and proinsulin levels were grossly elevated in the fasting state (C-peptide 2.2-3.5 pmol/ml; proinsulin approximately 1 pmol/ml). After an oral glucose tolerance test and intravenous arginine infusion, B cell hypersecretion was confirmed. The molar ratio of C-peptide to immunoreactive insulin, normally approximately 7, was about 0.3, clearly indicating that most of the immunoreactive insulin was exogenous. The molar ratio of proinsulin to C-peptide, which is about 0.05 in fasting control subjects, was 0.23-0.45, clearly showing that too high a proportion of proinsulin was being secreted. This may indicate that the constant hyperstimulation of the B cell leads to reduced conversion of proinsulin to insulin. Immunoreactive glucagon levels were within normal limits fasting but were above normal after intravenous arginine infusion. Thus, in this case of diabetes with acanthosis nigricans, the severe insulin resistance, probably caused by a receptor defect, was associated with markedly increased B cell function.

  1. Antigen Processing by Autoreactive B Cells Promotes Determinant Spreading

    Institute of Scientific and Technical Information of China (English)

    Yang D.Dai; George Carayanniotis; Eli Sercarz

    2005-01-01

    Acute primary immune responses tend to focus on few immunodominant determinants using a very limited number of T cell clones for expansion, whereas chronic inflammatory responses generally recruit a large number of different T cell clones to attack a broader range of determinants of the invading pathogens or the inflamed tissues.In T cell-mediated organ-specific autoimmune disease, a transition from the acute to the chronic phase contributes to pathogenesis, and the broadening process is called determinant spreading. The cellular components catalyzing the spreading reaction are not identified. It has been suggested that autoreactive B cells may play a central role in diversifying autoreactive T cell responses, possibly through affecting antigen processing and presentation. The clonal identity and diversity of the B cells and antibodies seem critical in regulating T cell activity and subsequent tissue damage or repair. Here, we use two autoimmune animal models, experimental autoimmune thyroiditis (EAT)and type 1 diabetes (T1D), to discuss how autoreactive B cells or antibodies alter the processing and presentation of autoantigens to regulate specific T cell response.

  2. How B cells shape the immune response against Mycobacterium tuberculosis.

    Science.gov (United States)

    Maglione, Paul J; Chan, John

    2009-03-01

    Extensive work illustrating the importance of cellular immune mechanisms for protection against Mycobacterium tuberculosis has largely relegated B-cell biology to an afterthought within the tuberculosis (TB) field. However, recent studies have illustrated that B lymphocytes, through a variety of interactions with the cellular immune response, play previously underappreciated roles in shaping host defense against non-viral intracellular pathogens, including M. tuberculosis. Work in our laboratory has recently shown that, by considering these lymphocytes more broadly within their variety of interactions with cellular immunity, B cells have a significant impact on the outcome of airborne challenge with M. tuberculosis as well as the resultant inflammatory response. In this review, we advocate for a revised view of TB immunology in which roles of cellular and humoral immunity are not mutually exclusive. In the context of our current understanding of host defense against non-viral intracellular infections, we review recent data supporting a more significant role of B cells during M. tuberculosis infection than previously thought.

  3. Treatment for a child with EBV-associated T/natural killer-cell lymphoproliferative disorder by hematopoietic stem cell transplantation%造血干细胞移植治疗儿童EB病毒相关T/NK细胞淋巴组织增殖性疾病疗效分析

    Institute of Scientific and Technical Information of China (English)

    吴南海; 龚小军; 栾佐; 王凯; 唐湘凤

    2012-01-01

    Objective To explore the therapeutic effect of hematopoietic stem cell transplantation for treatment of EBV-associated T/Natural Killer-cell Lymphoproliferative disorder in children. Methods A 13.5-year old boy .diagnosed with EBV-associated T/natural killer-cell lymphoproliferative disorder (EBV-T/NK-LPD) , received HLA-matched sibling PBSCT from his younger sister, as his disease was persistent after treatment with anti-virus drugs, EBV-CTL,interleukin-2 and chemotherapy. The conditioning regimen was TBI/CY+VP16 (total-body irradiation, 12 Gy in 8 fractions, -8d -5d; cyclophosphamide, 60mg/kgxtwo doses, -3d ~ -2d; a single dose of etoposide, 30mg/kg, -4d). The infused PBSCs contained 6.34×107kg nucleated cells and 3.80×106/ kg CD34 positive cells. GVHD prophylaxis consisted of cyclosporine A (CsA) and a short course of methotrexate (sMTX). Results The hematologic recovery was favorable. The patient achieved neutrophil engraftment at day +16;platelet engraftment was achieved at day +37;his hemo-gram completely recovered at day +60. The patient had no severe complications, such as fatal infections, hemorrhagic cystitis, veno-occlusive disease (VOD), interstitial pneumonia (IP),eytomegalovirus (CMV) infection, et al. He developed cutaneous Grade II acute graft-versus-host disease (GVHD) at day +62. The EBV-DNA was 1.2×105 copies/ml before transplant,and changed-over to negative at day +14; after this, the EBV-DNA was monitored weekly,persistently negative. After transplantation, the patient' s jaundice disappeared, and the liver function normalized. Rechecking type-B ultrasonic on the cervix and the abdomen, there was no signs of lymphadenectasis at pars cervicalis, hepatomega- ly , or splenomegaly; the previous lymphadenectasis at porta hepatic and aside abdominal aorta disappeared. Computed tomography scan at thorax dis- played no lymphadenectasis at portopulmonary, the mediastinum was normal. Up to now, and the patient has been followed up for 18 months after

  4. Selection of reference genes for quantitative PCR studies in purified B cells from B cell chronic lymphocytic leukaemia patients

    OpenAIRE

    Valceckiene, Vilma; Kontenyte, Rima; Jakubauskas, Arturas; Griskevicius, Laimonas

    2010-01-01

    Abstract Clinical heterogeneity of B-cell chronic lymphocytic leukaemia (B-CLL) makes it necessary to identify potent prognostic indicators to predict individual clinical course and select risk-adapted therapy. During the last years numerous gene expression models have been suggested as prognostic factors of B-CLL. Today quantitative polymerase chain reaction (qPCR) is a preferred method for rapid quantification of gene expression and validation of microarray data. Reliability of q...

  5. 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....... 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)....

  6. Monoclonal B-cell lymphocytosis (MBL) with normal lymphocyte counts is associated with decreased numbers of normal circulating B-cell subsets.

    Science.gov (United States)

    Hauswirth, Alexander W; Almeida, Julia; Nieto, Wendy G; Teodosio, Cristina; Rodriguez-Caballero, Arancha; Romero, Alfonso; López, Antonio; Fernandez-Navarro, Paulino; Vega, Tomas; Perez-Andres, Martin; Valent, Peter; Jäger, Ulrich; Orfao, Alberto

    2012-07-01

    Monoclonal B-cell lymphocytosis (MBL) with normal lymphocyte counts is associated with decreased numbers of normal circulating B-cell subsets.Little is known about the distribution of normal lymphoid cells and their subsets in the peripheral blood (PB) of subjects with monoclonal B-cell lymphocytosis (MBL). In our study, we compared the absolute number of PB lymphoid cells and their subpopulations in 95 MBL cases with normal lymphocyte counts vs. 617 age-/sex-matched non-MBL healthy subjects (controls), using highly sensitive flow cytometry. MBL cases showed significantly reduced numbers of normal circulating B-cells, at the expense of immature and naive B-cells; in addition, CD4+CD8+ double-positive T-cells and CD8+ T-cells were significantly lower and higher vs. controls, respectively. Moreover, most normal B-cell subsets were significantly decreased in PB at >1% MBL-counts, vs. "low-count" MBL cases, and lower amounts of immature/naive B-cells were detected in biclonal (particularly in cases with coexisting CLL-like- and non-CLL-like B-cell clones) vs. monoclonal MBL subjects. In summary, our results show imbalanced (reduced) absolute numbers of recently produced normal circulating B-cells (e.g., immature and naıve B-cells) in MBL, which becomes more pronounced as the MBL cell count increases.

  7. 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.

  8. 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.

  9. Revisiting the B-cell compartment in mouse and humans: more than one B-cell subset exists in the marginal zone and beyond

    Directory of Open Access Journals (Sweden)

    Garraud Olivier

    2012-11-01

    Full Text Available Abstract The immunological roles of B-cells are being revealed as increasingly complex by functions that are largely beyond their commitment to differentiate into plasma cells and produce antibodies, the key molecular protagonists of innate immunity, and also by their compartmentalisation, a more recently acknowledged property of this immune cell category. For decades, B-cells have been recognised by their expression of an immunoglobulin that serves the function of an antigen receptor, which mediates intracellular signalling assisted by companion molecules. As such, B-cells were considered simple in their functioning compared to the other major type of immune cell, the T-lymphocytes, which comprise conventional T-lymphocyte subsets with seminal roles in homeostasis and pathology, and non-conventional T-lymphocyte subsets for which increasing knowledge is accumulating. Since the discovery that the B-cell family included two distinct categories — the non-conventional, or extrafollicular, B1 cells, that have mainly been characterised in the mouse; and the conventional, or lymph node type, B2 cells — plus the detailed description of the main B-cell regulator, FcγRIIb, and the function of CD40+ antigen presenting cells as committed/memory B-cells, progress in B-cell physiology has been slower than in other areas of immunology. Cellular and molecular tools have enabled the revival of innate immunity by allowing almost all aspects of cellular immunology to be re-visited. As such, B-cells were found to express “Pathogen Recognition Receptors” such as TLRs, and use them in concert with B-cell signalling during innate and adaptive immunity. An era of B-cell phenotypic and functional analysis thus began that encompassed the study of B-cell microanatomy principally in the lymph nodes, spleen and mucosae. The novel discovery of the differential localisation of B-cells with distinct phenotypes and functions revealed the compartmentalisation of B-cells

  10. 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

    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...... center formation. As a major mediator of follicular B cell migration, the G protein-coupled receptor (GPCR) 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 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...

  11. 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...... activation through coculture with T cells activated by anti-T-cell receptor or anti-CD3 antibodies suggest that cellular interaction with T cells, independent of antigen presentation or lymphokine secretion, induces or triggers B cells to become responsive to T-derived lymphokines, and that this may...

  12. Primary Non-Hodgkin B Cell Lymphoma in a Man

    Directory of Open Access Journals (Sweden)

    Sh.M.I. Alhabshi

    2011-06-01

    Full Text Available Malignant breast lymphoma is a rare condition and primary breast lymphoma is extremely rare in"nthe male population. We present a case of a 26-year-old man (transgender who presented with a large palpable mass in the right breast. This mass was rapidly growing in size associated with right axillary lymphadenopathy. Ultrasound and MRI findings were consistent with BIRADS IV lesion which was suspicious of malignancy. Core biopsy was performed and histopathology confirmed the diagnosis of primary non Hodgkin B cell lymphoma of the breast.

  13. 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

    Since the original proposal by Fearon and Locksley (Fearon and Locksley. 1996. Science 272: 50-53) that the complement system linked innate and adaptive immunity, there has been a rapid expansion of studies on this topic. With the advance of intravital imaging, a number of recent papers revealed...... 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...

  14. Nivolumab With or Without Varlilumab in Treating Patients With Relapsed or Refractory Aggressive B-cell Lymphomas

    Science.gov (United States)

    2017-03-13

    Activated B-Cell-Like Diffuse Large B-Cell Lymphoma; ALK-Positive Large B-Cell Lymphoma; Atypical Burkitt/Burkitt-Like Lymphoma; Diffuse Large B-Cell Lymphoma Associated With Chronic Inflammation; Diffuse Large B-Cell Lymphoma, Not Otherwise Specified; Epstein-Barr Virus Positive Diffuse Large B-Cell Lymphoma of the Elderly; Epstein-Barr Virus-Positive Mucocutaneous Ulcer; Germinal Center B-Cell-Like Diffuse Large B-Cell Lymphoma; High-Grade B-Cell Lymphoma With MYC and BCL2 and/or BCL6 Rearrangements; Human Herpesvirus-8-Positive Neoplastic Cells Present; Intravascular Large B-Cell Lymphoma; MYC-Negative B-Cell Lymphoma With 11q Aberration Resembling Burkitt Lymphoma; Plasmablastic Lymphoma; Primary Cutaneous Diffuse Large B-Cell Lymphoma; Primary Cutaneous Diffuse Large B-Cell Lymphoma, Leg Type; Primary Diffuse Large B-Cell Lymphoma of the Central Nervous System; Primary Effusion Lymphoma; Recurrent Adult Burkitt Lymphoma; Recurrent Diffuse Large B-Cell Lymphoma; Recurrent Lymphomatoid Granulomatosis; Recurrent Mediastinal (Thymic) Large B-Cell Cell Lymphoma; Refractory Burkitt Lymphoma; Refractory Diffuse Large B-Cell Lymphoma; Refractory Mediastinal (Thymic) Large B-Cell Cell Lymphoma; Skin Ulcer; Small Intestinal B-Cell Lymphoma, Unclassifiable, With Features Intermediate Between Diffuse Large B-Cell Lymphoma and Burkitt Lymphoma; T-Cell/Histiocyte-Rich Large B-Cell Lymphoma

  15. B-cell activation in cats with feline infectious peritonitis (FIP) by FIP-virus-induced B-cell differentiation/survival factors.

    Science.gov (United States)

    Takano, Tomomi; Azuma, Natsuko; Hashida, Yoshikiyo; Satoh, Ryoichi; Hohdatsu, Tsutomu

    2009-01-01

    It has been suggested that antibody overproduction plays a role in the pathogenesis of feline infectious peritonitis (FIP). However, only a few studies on the B-cell activation mechanism after FIP virus (FIPV) infection have been reported. The present study shows that: (1) the ratio of peripheral blood sIg(+) CD21(-) B-cells was higher in cats with FIP than in SPF cats, (2) the albumin-to-globulin ratio has negative correlation with the ratio of peripheral blood sIg(+) CD21(-) B-cell, (3) cells strongly expressing mRNA of the plasma cell master gene, B-lymphocyte-induced maturation protein 1 (Blimp-1), were increased in peripheral blood in cats with FIP, (4) mRNA expression of B-cell differentiation/survival factors, IL-6, CD40 ligand, and B-cell-activating factor belonging to the tumor necrosis factor family (BAFF), was enhanced in macrophages in cats with FIP, and (5) mRNAs of these B-cell differentiation/survival factors were overexpressed in antibody-dependent enhancement (ADE)-induced macrophages. These data suggest that virus-infected macrophages overproduce B-cell differentiation/survival factors, and these factors act on B-cells and promote B-cell differentiation into plasma cells in FIPV-infected cats.

  16. B cell: T cell interactions occur within hepatic granulomas during experimental visceral leishmaniasis.

    Directory of Open Access Journals (Sweden)

    John W J Moore

    Full Text Available Hepatic resistance to Leishmania donovani infection in mice is associated with the development of granulomas, in which a variety of lymphoid and non-lymphoid populations accumulate. Although previous studies have identified B cells in hepatic granulomas and functional studies in B cell-deficient mice have suggested a role for B cells in the control of experimental visceral leishmaniasis, little is known about the behaviour of B cells in the granuloma microenvironment. Here, we first compared the hepatic B cell population in infected mice, where ≈60% of B cells are located within granulomas, with that of naïve mice. In infected mice, there was a small increase in mIgM(lomIgD(+ mature B2 cells, but no enrichment of B cells with regulatory phenotype or function compared to the naïve hepatic B cell population, as assessed by CD1d and CD5 expression and by IL-10 production. Using 2-photon microscopy to quantify the entire intra-granuloma B cell population, in conjunction with the adoptive transfer of polyclonal and HEL-specific BCR-transgenic B cells isolated from L. donovani-infected mice, we demonstrated that B cells accumulate in granulomas over time in an antigen-independent manner. Intra-vital dynamic imaging was used to demonstrate that within the polyclonal B cell population obtained from L. donovani-infected mice, the frequency of B cells that made multiple long contacts with endogenous T cells was greater than that observed using HEL-specific B cells obtained from the same inflammatory environment. These data indicate, therefore, that a subset of this polyclonal B cell population is capable of making cognate interactions with T cells within this unique environment, and provide the first insights into the dynamics of B cells within an inflammatory site.

  17. 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.

  18. Anticancer Effect of Curcumin on B Cell non- Hodgkin's Lymphoma

    Institute of Scientific and Technical Information of China (English)

    SUN Chunyan; LIU Xinyue; CHEN Yan; LIU Fang

    2005-01-01

    To explore the anticancer effect of curcumin on human B cell non-Hodgkin's lymphoma and compare its effects on human B cell non-Hodgkin's lymphoma cells and normal peripheral blood mononuclear cells (NPBMNCs). MTT assay was used to study the effect of curcumin on the growth of Raji cells and NPBMNCs. The effect of curcumin on the apoptosis of Raji cells and NPBMNC were studied by flow cytometry and TDT-mediated dUTP nick and labeling (TUNEL). The effect of curcumin on the cell cycle of Raji cells were examined by propidium iodide staining flow cytometry. The results showed that curcumin strongly inhibited ±1.82 μmol/L and curcumin induced Raji cell apoptosis in a time- and dose-dependent manner. Raji cells treated with curcumin showed curcumin did not demonstrate apparent proliferation inhibition and apoptosis induction in NPBMNCs. It was concluded that curcumin is able to inhibit the proliferation of Raji cells by regulating the cell cycle and inducing the cell apoptosis. Morever, curcumin has low toxicity on NPBMNCs but can selectively induce apoptosis in Raji cells.

  19. Immunoglobulin variable region structure and B-cell malignancies.

    Science.gov (United States)

    Kiyoi, H; Naoe, T

    2001-01-01

    The enormous diversity of immunoglobulin (Ig) variable (V) gene sequences encoding the antibody repertoire are formed by the somatic recombination of relatively few genetic elements. In B-lineage malignancies, Ig gene rearrangements have been widely used for determining clonality and cell origin. The recent development of rapid cloning and sequencing techniques has resulted in a substantial accumulation of IgV region sequences at various stages of B-cell development and has revealed stage-specific trends in the use of V, diversity, joining genes, the degree of noncoding nucleotide addition, and the rate of somatic mutations. Furthermore, sequences from B-lineage malignant cells nearly reflect the characteristics of the normal counterpart at each respective stage of development. Alternatively, from the IgV region structure of the malignant cells, it is possible to speculate at which stage of B-cell development the cells were transformed. As the complete nucleotide sequences of the human Ig heavy and Ig light V region loci have now been determined, the study of Ig genetics has entered into the super-information era.

  20. 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.

  1. Interleukin-35 induces regulatory B cells that suppress autoimmune disease.

    Science.gov (United States)

    Wang, Ren-Xi; Yu, Cheng-Rong; Dambuza, Ivy M; Mahdi, Rashid M; Dolinska, Monika B; Sergeev, Yuri V; Wingfield, Paul T; Kim, Sung-Hye; Egwuagu, Charles E

    2014-06-01

    Interleukin-10 (IL-10)-producing regulatory B (Breg) cells suppress autoimmune disease, and increased numbers of Breg cells prevent host defense to infection and promote tumor growth and metastasis by converting resting CD4(+) T cells to regulatory T (Treg) cells. The mechanisms mediating the induction and development of Breg cells remain unclear. Here we show that IL-35 induces Breg cells and promotes their conversion to a Breg subset that produces IL-35 as well as IL-10. Treatment of mice with IL-35 conferred protection from experimental autoimmune uveitis (EAU), and mice lacking IL-35 (p35 knockout (KO) mice) or defective in IL-35 signaling (IL-12Rβ2 KO mice) produced less Breg cells endogenously or after treatment with IL-35 and developed severe uveitis. Adoptive transfer of Breg cells induced by recombinant IL-35 suppressed EAU when transferred to mice with established disease, inhibiting pathogenic T helper type 17 (TH17) and TH1 cells while promoting Treg cell expansion. In B cells, IL-35 activates STAT1 and STAT3 through the IL-35 receptor comprising the IL-12Rβ2 and IL-27Rα subunits. As IL-35 also induced the conversion of human B cells into Breg cells, these findings suggest that IL-35 may be used to induce autologous Breg and IL-35(+) Breg cells and treat autoimmune and inflammatory disease.

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

    Institute of Scientific and Technical Information of China (English)

    Wei Liao; Sanjai Sharma

    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.

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

    Lifescience Database Archive (English)

    Full Text Available His.Bld.50.AllAg.Pro-B_cells mm9 Histone Blood Pro-B cells SRX668836,SRX1184113,SRX...09,SRX759800,SRX1143916,SRX1143902 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.Bld.50.AllAg.Pro-B_cells.bed ...

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

    Lifescience Database Archive (English)

    Full Text Available ALL.Bld.20.AllAg.Pro-B_cells mm9 All antigens Blood Pro-B cells SRX1553109,SRX15531...3,SRX1143907 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.Bld.20.AllAg.Pro-B_cells.bed ...

  5. Enhanced selection of high affinity DNA-reactive B cells following cyclophosphamide treatment in mice.

    Directory of Open Access Journals (Sweden)

    Daisuke Kawabata

    Full Text Available A major goal for the treatment of patients with systemic lupus erythematosus with cytotoxic therapies is the induction of long-term remission. There is, however, a paucity of information concerning the effects of these therapies on the reconstituting B cell repertoire. Since there is recent evidence suggesting that B cell lymphopenia might attenuate negative selection of autoreactive B cells, we elected to investigate the effects of cyclophosphamide on the selection of the re-emerging B cell repertoire in wild type mice and transgenic mice that express the H chain of an anti-DNA antibody. The reconstituting B cell repertoire in wild type mice contained an increased frequency of DNA-reactive B cells; in heavy chain transgenic mice, the reconstituting repertoire was characterized by an increased frequency of mature, high affinity DNA-reactive B cells and the mice expressed increased levels of serum anti-DNA antibodies. This coincided with a significant increase in serum levels of BAFF. Treatment of transgene-expressing mice with a BAFF blocking agent or with DNase to reduce exposure to autoantigen limited the expansion of high affinity DNA-reactive B cells during B cell reconstitution. These studies suggest that during B cell reconstitution, not only is negative selection of high affinity DNA-reactive B cells impaired by increased BAFF, but also that B cells escaping negative selection are positively selected by autoantigen. There are significant implications for therapy.

  6. B-type suppression: a role played by "regulatory B cells" or "regulatory plasma cells"?

    Science.gov (United States)

    Ries, Stefanie; Hilgenberg, Ellen; Lampropoulou, Vicky; Shen, Ping; Dang, Van Duc; Wilantri, Siska; Sakwa, Imme; Fillatreau, Simon

    2014-05-01

    B-cell depletion can improve disease in some patients with rheumatoid arthritis or multiple sclerosis, indicating the pathogenic contribution of B cells to autoimmunity. However, studies in mice have demonstrated that B cells have immunosuppressive functions as well, with IL-10 being a critical mediator of B-cell-mediated suppression. IL-10-secreting B cells have been shown to promote disease remission in some mouse models of autoimmune disorders. Human B cells also produce IL-10, and evidence is accumulating that human IL-10-producing B cells might inhibit immunity. There is considerable interest in identifying the phenotype of B cells providing IL-10 in a suppressive manner, which would facilitate the analysis of the molecular mechanisms controlling this B-cell property. Here, we review current knowledge on the B-cell subpopulations found to provide suppressive functions in mice, considering both the pathological context in which they were identified and the signals that control their induction. We discuss the phenotype of B cells that have IL-10-dependent regulatory activities in mice, which leads us to propose that antibody-secreting cells are, in some cases at least, the major source of B-cell-derived regulatory IL-10 in vivo. Anti-inflammatory cytokine production by antibody-secreting cells offers a novel mechanism for the coordination of innate and humoral immune responses.

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

    Lifescience Database Archive (English)

    Full Text Available His.Bld.20.AllAg.Pro-B_cells mm9 Histone Blood Pro-B cells SRX668836,SRX1184113,SRX...9,SRX1143910,SRX1143916,SRX1143902 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.Bld.20.AllAg.Pro-B_cells.bed ...

  8. Immunohistochemical classification and prognosis of diffuse large B-cell lymphoma in China

    Institute of Scientific and Technical Information of China (English)

    陈燕

    2014-01-01

    Objective To study the immunohistochemical classification and prognosis of diffuse large B-cell lymphoma(DLBCL).Methods A total of 148 cases of DLBCL were classified into germinal center B-cell-like(GCB)and non-GCB/activated B-cell-like(ABC)subtypes by Hans,Choi and Tally immunohistochemical stain algorithms.The clinical features and survival data of GCB

  9. 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

  10. Increased BCR responsiveness in B cells from patients with chronic GVHD.

    Science.gov (United States)

    Allen, Jessica L; Tata, Prasanthi V; Fore, Matthew S; Wooten, Jenna; Rudra, Sharmistha; Deal, Allison M; Sharf, Andrew; Hoffert, Todd; Roehrs, Philip A; Shea, Thomas C; Serody, Jonathan S; Richards, Kristy L; Jagasia, Madan; Lee, Stephanie J; Rizzieri, David; Horwitz, Mitchell E; Chao, Nelson J; Sarantopoulos, Stefanie

    2014-03-27

    Although B cells have emerged as important contributors to chronic graft-versus-host-disease (cGVHD) pathogenesis, the mechanisms responsible for their sustained activation remain unknown. We previously showed that patients with cGVHD have significantly increased B cell-activating factor (BAFF) levels and that their B cells are activated and resistant to apoptosis. Exogenous BAFF confers a state of immediate responsiveness to antigen stimulation in normal murine B cells. To address this in cGVHD, we studied B-cell receptor (BCR) responsiveness in 48 patients who were >1 year out from allogeneic hematopoietic stem cell transplantation (HSCT). We found that B cells from cGVHD patients had significantly increased proliferative responses to BCR stimulation along with elevated basal levels of the proximal BCR signaling components B cell linker protein (BLNK) and Syk. After initiation of BCR signaling, cGVHD B cells exhibited increased BLNK and Syk phosphorylation compared with B cells from patients without cGVHD. Blocking Syk kinase activity prevented relative post-HSCT BCR hyper-responsiveness of cGVHD B cells. These data suggest that a lowered BCR signaling threshold in cGVHD associates with increased B-cell proliferation and activation in response to antigen. We reveal a mechanism underpinning aberrant B-cell activation in cGVHD and suggest that therapeutic inhibition of the involved kinases may benefit these patients.

  11. Inhibition of demethylase KDM6B sensitizes diffuse large B-cell lymphoma to chemotherapeutic drugs

    Science.gov (United States)

    Mathur, Rohit; Sehgal, Lalit; Havranek, Ondrej; Köhrer, Stefan; Khashab, Tamer; Jain, Neeraj; Burger, Jan A.; Neelapu, Sattva S.; Davis, R. Eric; Samaniego, Felipe

    2017-01-01

    Histone methylation and demethylation regulate B-cell development, and their deregulation correlates with tumor chemoresistance in diffuse large B-cell lymphoma, limiting cure rates. Since histone methylation status correlates with disease aggressiveness and relapse, we investigated the therapeutic potential of inhibiting histone 3 Lys27 demethylase KDM6B, in vitro, using the small molecule inhibitor GSK-J4. KDM6B is overexpressed in the germinal center B-cell subtype of diffuse large B-cell lymphoma, and higher KDM6B levels are associated with worse survival in patients with diffuse large B-cell lymphoma treated with R-CHOP. GSK-J4-induced apoptosis was observed in five (SU-DHL-6, OCI-Ly1, Toledo, OCI-Ly8, SU-DHL-8) out of nine germinal center B-cell diffuse large B-cell lymphoma cell lines. Treatment with GSK-J4 predominantly resulted in downregulation of B-cell receptor signaling and BCL6. Cell lines expressing high BCL6 levels or CREBBP/EP300 mutations were sensitive to GSK-J4. Our results suggest that B-cell receptor-dependent downregulation of BCL6 is responsible for GSK-J4-induced cytotoxicity. Furthermore, GSK-J4-mediated inhibition of KDM6B sensitizes germinal center B-cell diffuse large B-cell lymphoma cells to chemotherapy agents that are currently utilized in treatment regimens for diffuse large B-cell lymphoma. PMID:27742770

  12. 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.

  13. Separation of plasmacytoid dendritic cells from B-cell-biased lymphoid progenitor (BLP and Pre-pro B cells using PDCA-1.

    Directory of Open Access Journals (Sweden)

    Kay L Medina

    Full Text Available B-cell-biased lymphoid progenitors (BLPs and Pre-pro B cells lie at a critical juncture between B cell specification and commitment. However, both of these populations are heterogenous, which hampers investigation into the molecular changes that occur as lymphoid progenitors commit to the B cell lineage. Here, we demonstrate that there are PDCA-1(+Siglec H(+ plasmacytoid dendritic cells (pDCs that co-purify with BLPs and Pre-pro B cells, which express little or no CD11c or Ly6C. Removal of PDCA-1(+ pDCs separates B cell progenitors that express high levels of a Rag1-GFP reporter from Rag1-GFP(low/neg pDCs within the BLP and Pre-pro B populations. Analysis of Flt3-ligand knockout and IL-7Rα knockout mice revealed that there is a block in B cell development at the all-lymphoid progenitor (ALP stage, as the majority of cells within the BLP or Pre-pro B gates were PDCA-1(+ pDCs. Thus, removal of PDCA-1(+ pDCs is critical for analysis of BLP and Pre-pro B cell populations. Analysis of B cell potential within the B220(+CD19(- fraction demonstrated that AA4.1(+Ly6D(+PDCA-1(- Pre-pro B cells gave rise to CD19(+ B cells at high frequency, while PDCA-1(+ pDCs in this fraction did not. Interestingly, the presence of PDCA-1(+ pDCs within CLPs may help to explain the conflicting results regarding the origin of these cells.

  14. CD83 modulates B cell function in vitro: increased IL-10 and reduced Ig secretion by CD83Tg B cells.

    Directory of Open Access Journals (Sweden)

    Birte Kretschmer

    Full Text Available The murine transmembrane glycoprotein CD83 is an important regulator for both thymic T cell maturation and peripheral T cell responses. Recently, we reported that CD83 also has a function on B cells: Ubiquitous transgenic (Tg expression of CD83 interfered with the immunoglobulin (Ig response to infectious agents and to T cell dependent as well as T cell independent model antigen immunization. Here we compare the function of CD83Tg B cells that overexpress CD83 and CD83 mutant (CD83mu B cells that display a drastically reduced CD83 expression. Correlating with CD83 expression, the basic as well as the lipopolysaccharide (LPS induced expression of the activation markers CD86 and MHC-II are significantly increased in CD83Tg B cells and reciprocally decreased in CD83mu B cells. Wild-type B cells rapidly upregulate CD83 within three hours post BCR or TLR engagement by de novo protein synthesis. The forced premature overexpression of CD83 on the CD83Tg B cells results in reduced calcium signaling, reduced Ig secretion and a reciprocally increased IL-10 production upon in vitro activation. This altered phenotype is mediated by CD83 expressed on the B cells themselves, since it is observed in the absence of accessory cells. In line with this finding, purified CD83mu B cells displayed a reduced IL-10 production and slightly increased Ig secretion upon LPS stimulation in vitro. Taken together, our data strongly suggest that CD83 is expressed by B cells upon activation and contributes to the regulation of B cell function.

  15. Characterization of Regulatory B Cells in Graves’ Disease and Hashimoto’s Thyroiditis

    Science.gov (United States)

    Kristensen, Birte; Hegedüs, Laszlo; Lundy, Steven K.; Brimnes, Marie K.; Smith, Terry J.; Nielsen, Claus H.

    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, but not in cells from patients with HT. In GD, B cells primed with TG induced IL-10-producing CD4+ T cells. To assess the maximal frequency of inducible IL-10+ B cells in the three donor groups PBMCs were stimulated with PMA/ionomycin. The resulting IL-10+ B-cell frequency was similar in the three groups 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 not differ between patients and healthy donors. In conclusion, our findings indicate that autoimmune thyroiditis is not associated with reduced frequency of IL-10+ B cells. These results do not rule out regulatory B-cell dysfunction, however. The observed phenotypic differences between IL-10+ B cells from patients and healthy donors are discussed. PMID:26016954

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

    Science.gov (United States)

    Kristensen, Birte; Hegedüs, Laszlo; Lundy, Steven K; Brimnes, Marie K; Smith, Terry J; Nielsen, Claus H

    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, but not in cells from patients with HT. In GD, B cells primed with TG induced IL-10-producing CD4+ T cells. To assess the maximal frequency of inducible IL-10+ B cells in the three donor groups PBMCs were stimulated with PMA/ionomycin. The resulting IL-10+ B-cell frequency was similar in the three groups 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 not differ between patients and healthy donors. In conclusion, our findings indicate that autoimmune thyroiditis is not associated with reduced frequency of IL-10+ B cells. These results do not rule out regulatory B-cell dysfunction, however. The observed phenotypic differences between IL-10+ B cells from patients and healthy donors are discussed.

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

    Directory of Open Access Journals (Sweden)

    Birte Kristensen

    Full Text Available 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, but not in cells from patients with HT. In GD, B cells primed with TG induced IL-10-producing CD4+ T cells. To assess the maximal frequency of inducible IL-10+ B cells in the three donor groups PBMCs were stimulated with PMA/ionomycin. The resulting IL-10+ B-cell frequency was similar in the three groups 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 not differ between patients and healthy donors. In conclusion, our findings indicate that autoimmune thyroiditis is not associated with reduced frequency of IL-10+ B cells. These results do not rule out regulatory B-cell dysfunction, however. The observed phenotypic differences between IL-10+ B cells from patients and healthy donors are discussed.

  18. Essential role of MALT1 protease activity in activated B cell-like diffuse large B-cell lymphoma.

    Science.gov (United States)

    Hailfinger, Stephan; Lenz, Georg; Ngo, Vu; Posvitz-Fejfar, Anita; Rebeaud, Fabien; Guzzardi, Montserrat; Penas, Eva-Maria Murga; Dierlamm, Judith; Chan, Wing C; Staudt, Louis M; Thome, Margot

    2009-11-24

    A key element for the development of suitable anti-cancer drugs is the identification of cancer-specific enzymatic activities that can be therapeutically targeted. Mucosa-associated lymphoid tissue transformation protein 1 (MALT1) is a proto-oncogene that contributes to tumorigenesis in diffuse large B-cell lymphoma (DLBCL) of the activated B-cell (ABC) subtype, the least curable subtype of DLBCL. Recent data suggest that MALT1 has proteolytic activity, but it is unknown whether this activity is relevant for tumor growth. Here we report that MALT1 is constitutively active in DLBCL lines of the ABC but not the GCB subtype. Inhibition of the MALT1 proteolytic activity led to reduced expression of growth factors and apoptosis inhibitors, and specifically affected the growth and survival of ABC DLBCL lines. These results demonstrate a key role for the proteolytic activity of MALT1 in DLBCL of the ABC subtype, and provide a rationale for the development of pharmacological inhibitors of MALT1 in DLBCL therapy.

  19. Diagnosis and treatment of post-transplant lymphoproliferative disease after hematopoietic stem cell transplantation: Report of one case and literature review%异基因造血干细胞移植后淋巴组织增殖性疾病一例并文献复习

    Institute of Scientific and Technical Information of China (English)

    唐晓琼; 刘林; 罗小华; 陈建斌; 杨梨

    2013-01-01

    Objective To investigate the diagnosis and treatment of post-transplant lymphoproliferative disease (PTLD) after hematopoietic stem cell transplantation (HSCT).Methods Clinical data of one case of PTLD,including clinical manifestations,diagnosis and treatment,were retrospectively analyzed.And the related literatures were reviewed.Results From January 2007 to November 2012,one case developed PTLD among 196 patients who were followed up after HSCT in the First Affiliated Hospital of Chongqing Medical University.The incidence of PTLD was 0.5%.Clinical manifestations of the patient were not typical,including frequent fever,multiple lymphadenopathy and multiple pulmonary nodules.The patient was diagnosed as diffuse large B-cell lymphoma (B-DLCL) by pathological examination of the swollen lymph node.After withdrawal of immunosuppressants,the temperature returned to normal,and lymphadenopathy and pulmonary nodules disappeared completely.Conclusion PTLD is a severe complication of HSCT with distinctive morphologic and clinical characteristics.The origin of this disease may be associated with Epstein-Barr virus infection and imrnunosuppressive therapy.It needs the pathologic detection to make a definite diagnosis.Several different treatment strategies have been employed,and reduction of immunosuppressive therapy may lead to regression of PTLD.%目的 探讨造血干细胞移植术后淋巴组织增殖性疾病(PTLD)的诊断和治疗.方法 回顾性分析1例异基因造血干细胞移植后PTLD的临床表现、诊断和治疗过程,并复习相关文献.结果 2007年1月至2012年11月196例造血干细胞移植后受者中有1例发生PTLD,发生率为0.5%.该例受者的临床表现不典型,主要表现为反复发热、多处淋巴结肿大和肺部多发性结节病变等,淋巴结活检提示弥漫大B细胞淋巴瘤.停用免疫抑制剂2个月后体温恢复正常,肿大的淋巴结和肺部结节病变完全消失.结论 PTLD是造血干细胞移植术后

  20. Human innate B cells: a link between host defense and autoimmunity?

    Science.gov (United States)

    Milner, Eric C B; Anolik, Jennifer; Cappione, Amedeo; Sanz, Iñaki

    2005-03-01

    B cells play a variety of immunoregulatory roles through their antigen-presentation ability and through cytokine and chemokine production. Innate immune activation of B cells may play a beneficial role through the generation of natural cross-reactive antibodies, by maintaining B cell memory and by exercising immunomodulatory functions that may provide protection against autoimmunity. In this article, we review human B cell populations and their functional properties, with a particular focus on a population of inherently autoreactive B cells, which seem to play an important physiological role in innate immunity, but which, if selected into adaptive immune responses, appear to become pathogenic agents in systemic lupus erythematosus.

  1. 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...

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

    DEFF Research Database (Denmark)

    Xia, Y; 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...

  3. Early B-cell-specific inactivation of ATM synergizes with ectopic CyclinD1 expression to promote pre-germinal center B-cell lymphomas in mice.

    Science.gov (United States)

    Yamamoto, K; Lee, B J; Li, C; Dubois, R L; Hobeika, E; Bhagat, G; Zha, S

    2015-06-01

    Ataxia telangiectasia-mutated (ATM) kinase is a master regulator of the DNA damage response. ATM is frequently inactivated in human B-cell non-Hodgkin lymphomas, including ~50% of mantle cell lymphomas (MCLs) characterized by ectopic expression of CyclinD1. Here we report that early and robust deletion of ATM in precursor/progenitor B cells causes cell autonomous, clonal mature B-cell lymphomas of both pre- and post-germinal center (GC) origins. Unexpectedly, naive B-cell-specific deletion of ATM is not sufficient to induce lymphomas in mice, highlighting the important tumor suppressor function of ATM in immature B cells. Although EμCyclinD1 is not sufficient to induce lymphomas, EμCyclinD1 accelerates the kinetics and increases the incidence of clonal lymphomas in ATM-deficient B-cells and skews the lymphomas toward pre-GC-derived small lymphocytic neoplasms, sharing morphological features of human MCL. This is in part due to CyclinD1-driven expansion of ATM-deficient naive B cells with genomic instability, which promotes the deletions of additional tumor suppressor genes (i.e. Trp53, Mll2, Rb1 and Cdkn2a). Together these findings define a synergistic function of ATM and CyclinD1 in pre-GC B-cell proliferation and lymphomagenesis and provide a prototypic animal model to study the pathogenesis of human MCL.

  4. Early B-cell Specific Inactivation of ATM Synergizes with Ectopic CyclinD1 Expression to Promote Pre-germinal center B-cell Lymphomas in Mice

    Science.gov (United States)

    Yamamoto, Kenta; Lee, Brian J.; Li, Chen; Dubois, Richard L.; Hobeika, Elias; Bhagat, Govind; Zha, Shan

    2017-01-01

    Ataxia Telangiectasia Mutated (ATM) kinase is a master regulator of the DNA damage response. ATM is frequently inactivated in human B-cell non-Hodgkin Lymphomas (B-NHL), including ~50% of mantle cell lymphomas (MCLs) characterized by ectopic expression of CyclinD1. Here we report that early and robust deletion of ATM in precursor/progenitor B-cells causes cell-autonomous, clonal mature B cell lymphomas of both pre- and post-germinal center (GC) origins. Unexpectedly naïve B cell specific deletion of ATM is not sufficient to induce lymphomas in mice, highlighting the important tumor suppressor function of ATM in immature B cells. While EμCyclinD1 is not sufficient to induce lymphomas, EμCyclinD1 accelerates the kinetics and increased the incidence of clonal lymphomas in ATM-deficient B-cells and skews the lymphomas towards pre-GC derived small lymphocytic neoplasms sharing morphological features of human MCL. This is in part due to CyclinD1-driven expansion of ATM-deficient naïve B cells with genomic instability, which promotes the deletions of additional tumor suppressor genes (i.g. Trp53, Mll2, Rb1 and Cdkn2a). Together these findings define a synergistic function of ATM and CyclinD1 in pre-germinal center B-cell proliferation and lymphomagenesis and provide a prototypic animal model to study the pathogenesis of human MCL. PMID:25676421

  5. Bruton's tyrosine kinase cooperates with the B cell linker protein SLP-65 as a tumor suppressor in Pre-B cells

    NARCIS (Netherlands)

    R. Kersseboom (Rogier); S. Middendorp; G.M. Dingjan (Gemma); K. Dahlenborg; M. Reth; H. Jumaa; R.W. Hendriks (Rudi)

    2003-01-01

    textabstractExpression of the pre-B cell receptor (pre-BCR) leads to activation of the adaptor molecule SLP-65 and the cytoplasmic kinase Btk. Mice deficient for one of these signaling proteins have an incomplete block in B cell development at the stage of large cycling

  6. Distinct T helper cell dependence of memory B-cell proliferation versus plasma cell differentiation.

    Science.gov (United States)

    Zabel, Franziska; Fettelschoss, Antonia; Vogel, Monique; Johansen, Pål; Kündig, Thomas M; Bachmann, Martin F

    2017-03-01

    Several memory B-cell subclasses with distinct functions have been described, of which the most effective is the class-switched (CS) memory B-cell population. We have previously shown, using virus-like particles (VLPs), that the proliferative potential of these CS memory B cells is limited and they fail to re-enter germinal centres (GCs). However, VLP-specific memory B cells quickly differentiated into secondary plasma cells (PCs) with the virtue of elevated antibody production compared with primary PCs. Whereas the induction of VLP(+) memory B cells was strongly dependent on T helper cells, we were wondering whether re-stimulation of VLP(+) memory B cells and their differentiation into secondary PCs would also require T helper cells. Global absence of T helper cells led to strongly impaired memory B cell proliferation and PC differentiation. In contrast, lack of interleukin-21 receptor-dependent follicular T helper cells or CD40 ligand signalling strongly affected proliferation of memory B cells, but differentiation into mature secondary PCs exhibiting increased antibody production was essentially normal. This contrasts with primary B-cell responses, where a strong dependence on CD40 ligand but limited importance of interleukin-21 receptor was seen. Hence, T helper cell dependence differs between primary and secondary B-cell responses as well as between memory B-cell proliferation and PC differentiation.

  7. Interleukin-24 inhibits the plasma cell differentiation program in human germinal center B cells.

    Science.gov (United States)

    Maarof, Ghyath; Bouchet-Delbos, Laurence; Gary-Gouy, Hélène; Durand-Gasselin, Ingrid; Krzysiek, Roman; Dalloul, Ali

    2010-03-04

    Complex molecular mechanisms control B-cell fate to become a memory or a plasma cell. Interleukin-24 (IL-24) is a class II family cytokine of poorly understood immune function that regulates the cell cycle. We previously observed that IL-24 is strongly expressed in leukemic memory-type B cells. Here we show that IL-24 is also expressed in human follicular B cells; it is more abundant in CD27(+) memory B cells and CD5-expressing B cells, whereas it is low to undetectable in centroblasts and plasma cells. Addition of IL-24 to B cells, cultured in conditions shown to promote plasma cell differentiation, strongly inhibited plasma cell generation and immunoglobulin G (IgG) production. By contrast, IL-24 siRNA increased terminal differentiation of B cells into plasma cells. IL-24 is optimally induced by BCR triggering and CD40 engagement; IL-24 increased CD40-induced B-cell proliferation and modulated the transcription of key factors involved in plasma cell differentiation. It also inhibited activation-induced tyrosine phosphorylation of signal transducer and activator of transcription-3 (STAT-3), and inhibited the transcription of IL-10. Taken together, our results indicate that IL-24 is a novel cytokine involved in T-dependent antigen (Ag)-driven B-cell differentiation and suggest its physiologic role in favoring germinal center B-cell maturation in memory B cells at the expense of plasma cells.

  8. 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.

  9. 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.

  10. MabCampath可有效治疗B-Cell CLL

    Institute of Scientific and Technical Information of China (English)

    杨绍杰(摘)

    2006-01-01

    根据在《临床肿瘤学杂志》第10期上公布的数据,美国GenzymeOncology集团开发的MabCampath(alemtuzumab)(Ⅰ)与Fludara(fludarabine phosphate,伏达拉滨)(Ⅱ)联合使用可有效治疗B细胞慢性淋巴细胞性白血病(B-Cell CLL),在研究期间总应答率为83%。Berlex公司(Schering AG公司的子公司)在美国销售(Ⅰ)。

  11. A primitive cell origin for B-cell precursor ALL?

    Science.gov (United States)

    Cox, C V; Blair, A

    2005-01-01

    A stem cell origin has been described for both acute and chronic myelogenous leukemias. In contrast, childhood B-cell precursor acute lymphoblastic leukemia (ALL) is thought to arise in committed B-lineage cells. Recently described in vitro and in vivo model systems that support the proliferation and expansion of ALL cells have provided new tools to investigate the cellular targets for the origin of this malignancy. Evidence suggests that some subtypes of childhood ALL have a primitive cell origin and share many immunophenotypic characteristics with normal progenitor cells. These leukemic stem cells may be resistant to current therapeutic strategies designed to kill the bulk ALL cell population and subsequent relapses may arise from this population. More precise definition of these ALL stem cells through combined analyses of antigen expression, genetic lesions, and functionality is essential for the development of more effective, targeted therapeutic strategies.

  12. TP53 dysfunction in diffuse large B-cell lymphoma.

    Science.gov (United States)

    Lu, Ting-Xun; Young, Ken H; Xu, Wei; Li, Jian-Yong

    2016-01-01

    The aberrations of TP53 gene and dysregulation of the TP53 pathway are important in the pathogenesis of many human cancers, including malignant lymphomas, especially for diffuse large B cell lymphoma (DLBCL). By regulating many downstream target genes or molecules, TP53 governs major defenses against tumor growth and promotes cellular DNA repair, apoptosis, autophagy, cell cycle arrest, signaling, transcription, immune or inflammatory responses and metabolism. Dysfunction of TP53, including microRNA regulations, copy number alterations of TP53 pathway and TP53 itself, dysregulation of TP53 regulators, and somatic mutations by abnormal TP53 function modes, play an important role in lymphoma generation, progression and invasion. The role of TP53 in DLBCL has been widely explored recently. In this review, we summarized recent advances on different mechanisms of TP53 in DLBCL and new therapeutic approaches to overcome TP53 inactivation.

  13. Targeting B-cell maturation antigen in multiple myeloma

    Science.gov (United States)

    Tai, Yu-Tzu; Anderson, Kenneth C

    2015-01-01

    Novel effective immunotherapies are needed for patients with multiple myeloma (MM), since disease recurrence remains a major obstacle. B-cell maturation antigen (BCMA), a cell surface protein universally expressed on malignant plasma cells , has emerged as a very selective antigen to be targeted in novel treatments for MM. We here first review BCMA-related biology, and then highlight the recent clinical development of a novel afucosylated anti-BCMA monoclonal antibody conjugated with monomethyl auristatin F via noncleavable linker (GSK2857916). Chimeric antigen receptor-expressing T cells targeting BCMA may also induce specific and durable anti-MM responses by patients’ own effector cells. Clinical trials testing these two approaches (NCT02064387, NCT02215967) are currently ongoing in relapsed and refractory MM patients. PMID:26370838

  14. Lenalidomide in Diffuse Large B-Cell Lymphoma

    Directory of Open Access Journals (Sweden)

    Catherine Thieblemont

    2012-01-01

    Full Text Available Diffuse large B-cell lymphoma (DLBCL is the most common form of non-Hodgkin's lymphoma (NHL in adults. Even if the natural history of DLBCL has been improved with the advent of immunochemotherapy, the survival results obtained with current treatment options clearly indicate that new agents or novel approaches are needed. Lenalidomide (Revlimid, Celgene Corporation, Summit, NJ, USA, an analogue of thalidomide, is an immunomodulatory drug with pleiotropic mechanisms of action potentially adding to immunochemotherapy. We present here the biological rational for the use of lenalidomide in DLBCL in light of recent advances in the pathophysiology of the disease and the therapeutic results of the most recent trials published in literature or reported in meetings in relapsed/refractory situations as well as in first-line treatment.

  15. Lenalidomide in diffuse large B-cell lymphoma.

    Science.gov (United States)

    Thieblemont, Catherine; Delfau-Larue, Marie-Hélène; Coiffier, Bertrand

    2012-01-01

    Diffuse large B-cell lymphoma (DLBCL) is the most common form of non-Hodgkin's lymphoma (NHL) in adults. Even if the natural history of DLBCL has been improved with the advent of immunochemotherapy, the survival results obtained with current treatment options clearly indicate that new agents or novel approaches are needed. Lenalidomide (Revlimid, Celgene Corporation, Summit, NJ, USA), an analogue of thalidomide, is an immunomodulatory drug with pleiotropic mechanisms of action potentially adding to immunochemotherapy. We present here the biological rational for the use of lenalidomide in DLBCL in light of recent advances in the pathophysiology of the disease and the therapeutic results of the most recent trials published in literature or reported in meetings in relapsed/refractory situations as well as in first-line treatment.

  16. [Posterior uveitis caused by highly malignant B cell lymphoma].

    Science.gov (United States)

    Held, R; Eckardt, C; Brix, F; Feller, A C

    1989-01-01

    A diagnostic vitrectomy was performed on three patients with posterior uveitis of unknown origin and whose vitrous body was markedly affected. In all cases, cells of high-grade B-cell lymphoma (earlier referred to as reticulum cell sarcoma) were identified by cytological analysis of the specimen. In addition to the ocular findings, one of the three patients showed clinical and radiological evidence of a tumorous mass in the area of the right thalamus at the time of diagnosis. This was interpreted as a cerebral manifestation of the lymphoma. Initially, the other two patients did not show any cerebral involvement. One of them, however, developed clinical symptoms 9 months after diagnosis, which were radiologically verified as tumor infiltration of the cerebellum and the diencephalon. Under radiation therapy, the ocular findings disappeared within a few weeks.

  17. Coordinate suppression of B cell lymphoma by PTEN and SHIP phosphatases

    DEFF Research Database (Denmark)

    Miletic, Ana V; Anzelon-Mills, Amy N; Mills, David M

    2010-01-01

    results in lethal T cell lymphomas, we find that animals lacking PTEN or SHIP in B cells show no evidence of malignancy. However, concomitant deletion of PTEN and SHIP (bPTEN/SHIP(-/-)) results in spontaneous and lethal mature B cell neoplasms consistent with marginal zone lymphoma or, less frequently......, follicular or centroblastic lymphoma. bPTEN/SHIP(-/-) B cells exhibit enhanced survival and express more MCL1 and less Bim. These cells also express low amounts of p27(kip1) and high amounts of cyclin D3 and thus appear poised to undergo proliferative expansion. Unlike normal B cells, bPTEN/SHIP(-/-) B cells...... proliferate to the prosurvival factor B cell activating factor (BAFF). Interestingly, although BAFF availability may promote lymphoma progression, we demonstrate that BAFF is not required for the expansion of transferred bPTEN/SHIP(-/-) B cells. This study reveals that PTEN and SHIP act cooperatively...

  18. 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

    BACKGROUND: B cells positively contribute to immunity by antigen presentation to CD4(+) T cells, cytokine production, and differentiation into antibody secreting plasma cells. Accumulating evidence implies that B cells also possess immunoregulatory functions closely linked to their capability of IL......-10 secretion. METHODS: Colitis development was followed in CD4(+) CD25(-) T cell transplanted SCID mice co-transferred with B cells exposed to an enterobacterial extract (ebx-B cells). B and T cell cytokine expression was measured by flow cytometry and enzyme-linked immunosorbent assay (ELISA......). 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...

  19. Anti-B-Cell Therapies in Autoimmune Neurological Diseases: Rationale and Efficacy Trials.

    Science.gov (United States)

    Alexopoulos, Harry; Biba, Angie; Dalakas, Marinos C

    2016-01-01

    B cells have an ever-increasing role in the etiopathology of a number of autoimmune neurological disorders, acting as antibody-producing cells and, most importantly, as sensors, coordinators, and regulators of the immune response. B cells, among other functions, regulate the T-cell activation process through their participation in antigen presentation and production of cytokines. The availability of monoclonal antibodies or fusion proteins against B-cell surface molecules or B-cell trophic factors bestows a rational approach for treating autoimmune neurological disorders, even when T cells are the main effector cells. This review summarizes basic aspects of B-cell biology, discusses the role(s) of B cells in neurological autoimmunity, and presents anti-B-cell drugs that are either currently on the market or are expected to be available in the near future for treating neurological autoimmune disorders.

  20. Regulatory constraints in the generation and differentiation of IgE-expressing B cells.

    Science.gov (United States)

    Yang, Zhiyong; Robinson, Marcus J; Allen, Christopher D C

    2014-06-01

    B cells expressing antibodies of the immunoglobulin E (IgE) isotype are rare, yet are heavily implicated in the pathogenesis of allergies and asthma. This review discusses recent methodological advances that permit sensitive probing of IgE-expressing (IgE(+)) B cells in vivo and have accordingly clarified the basic behavior and fate of IgE(+) B cells during immune responses in mouse models. IgE antibody secreting plasma cells can arise from extrafollicular foci, germinal centers, and memory B cells. However, compared to B cells expressing other isotypes, IgE(+) B cells are susceptible to multiple additional regulatory constraints that restrict the size of the IgE(+) B cell pool at each stage, coordinately limiting the overall magnitude, affinity, and duration of the IgE antibody response.

  1. T-cell leukemia 1 expression in nodal Epstein-Barr virus-negative diffuse large B-cell lymphoma and primary mediastinal B-cell lymphoma.

    Science.gov (United States)

    Gualco, Gabriela; Weiss, Lawrence M; Barber, Glen N; Bacchi, Carlos E

    2010-09-01

    The physiologic expression of the product of the proto-oncogene TCL1 (T-cell leukemia 1) is primarily restricted to early embryonic cells. In nonneoplastic B cells, the expression of TCL1 is determined by the differentiation step with silencing at the germinal center stage. TCL1 protein is overexpressed in a wide variety of human diseases. It has been shown that TCL1 is a powerful B-cell oncogene, which has been implicated in the pathogenesis of various types of mature B-cell lymphomas. There is no comparative information in the literature addressing the expression of TCL1 in pediatric and adult nodal diffuse large B-cell lymphoma or primary mediastinal large B-cell lymphoma. We studied 55 cases of adult and pediatric diffuse large B-cell lymphoma and primary mediastinal large B-cell lymphoma to analyze the phenotypic profile of these lymphomas, including TCL1 expression, and its relationship with clinical outcome in different age groups. The cases were analyzed by immunohistochemistry for the expression of TCL1, CD10, BCL-2, BCL-6, and MUM1. We also evaluated c-MYC translocation by fluorescence in situ hybridization. TCL1 was observed in 11 cases, 5 pediatric and 6 adult cases, all but one diffuse large B-cell lymphoma. Pediatric cases showed a significant association between TCL1 expression, high proliferative index, and presence of c-MYC translocation. TCL1 positivity was predominantly found in germinal center phenotype diffuse large B-cell lymphoma. Overall survival was worse in adult TCL1-positive cases than pediatric ones. Primary mediastinal large B-cell lymphomas infrequently expressed TCL1 in both age groups.

  2. B cell depletion inhibits spontaneous autoimmune thyroiditis in NOD.H-2h4 mice.

    Science.gov (United States)

    Yu, Shiguang; Dunn, Robert; Kehry, Marilyn R; Braley-Mullen, Helen

    2008-06-01

    B cells are important for the development of most autoimmune diseases. B cell depletion immunotherapy has emerged as an effective treatment for several human autoimmune diseases, although it is unclear whether B cells are necessary for disease induction, autoantibody production, or disease progression. To address the role of B cells in a murine model of spontaneous autoimmune thyroiditis (SAT), B cells were depleted from adult NOD.H-2h4 mice using anti-mouse CD20 mAb. Anti-CD20 depleted most B cells in peripheral blood and cervical lymph nodes and 50-80% of splenic B cells. Flow cytometry analysis showed that marginal zone B cells in the spleen were relatively resistant to depletion by anti-CD20, whereas most follicular and transitional (T2) B cells were depleted after anti-CD20 treatment. When anti-CD20 was administered before development of SAT, development of SAT and anti-mouse thyroglobulin autoantibody responses were reduced. Anti-CD20 also reduced SAT severity and inhibited further increases in anti-mouse thyroglobulin autoantibodies when administered to mice that already had autoantibodies and thyroid inflammation. The results suggest that B cells are necessary for initiation as well as progression or maintenance of SAT in NOD.H-2h4 mice.

  3. IL-4Rα-Associated Antigen Processing by B Cells Promotes Immunity in Nippostrongylus brasiliensis Infection

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    Hoving, Jennifer C.; Nieuwenhuizen, Natalie; McSorley, Henry J.; Ndlovu, Hlumani; Bobat, Saeeda; Kimberg, Matti; Kirstein, Frank; Cutler, Anthony J.; DeWals, Benjamin; Cunningham, Adam F.; Brombacher, Frank

    2013-01-01

    In this study, B cell function in protective TH2 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. PMID:24204255

  4. Natalizumab treatment leads to an increase in circulating CXCR3-expressing B cells

    Science.gov (United States)

    Penttilä, Tarja-Leena; Airas, Laura

    2016-01-01

    Objective: To study the effects of natalizumab treatment on subgroups of circulating peripheral blood B cell populations. Methods: We studied the proportions and absolute numbers of CD19+CD20+, CD10+, and CD5+ B cell populations, and determined very late activation antigen-4 and chemokine receptor CXCR3, CCR5, and CCR6 expression on B cells in the peripheral blood of 14 natalizumab-treated patients with relapsing-remitting multiple sclerosis. Five blood samples per patient were obtained longitudinally before and during the first year of treatment. Blood samples were analyzed by 6-color flow cytometry. Results: Proportions of B cells and CD10+ pre–B cells were significantly increased, and very late activation antigen-4 expression on the B cell surface was significantly decreased already after 1 week of natalizumab treatment. Natalizumab-induced sustained increase in the proportion and absolute number of CXCR3-expressing B cells was statistically significant after 1 month of treatment. There were no changes in the proportions of CCR5- or CCR6-expressing B cells. Conclusions: The rapid and persistent increase in circulating CXCR3-expressing B cells in response to natalizumab treatment possibly reflects the relevance of this chemokine receptor in controlling migration of B cells into the CNS in humans in vivo. PMID:27800533

  5. B cells responses and cytokine production are regulated by their immune microenvironment.

    Science.gov (United States)

    Vazquez, Monica I; Catalan-Dibene, Jovani; Zlotnik, Albert

    2015-08-01

    The adaptive immune system consists of two types of lymphocytes: T and B cells. These two lymphocytes originate from a common precursor, yet are fundamentally different with B cells mediating humoral immunity while T cells mediate cell mediated immunity. In cytokine production, naïve T cells produce multiple cytokines upon activation while naïve activated B cells do not. B cells are capable of producing cytokines, but their cytokine production depends on their differentiation state and activation conditions. Hence, unlike T cells that can produce a large amount of cytokines upon activation, B cells require specific differentiation and activation conditions to produce cytokines. Many cytokines act on B cells as well. Here, we discuss several cytokines and their effects on B cells including: Interleukins, IL-7, IL-4, IL-6, IL-10, and Interferons, IFN-α, IFN-β, IFN-γ. These cytokines play important roles in the development, survival, differentiation and/or proliferation of B cells. Certain chemokines also play important roles in B cell function, namely antibody production. As an example, we discuss CCL28, a chemokine that directs the migration of plasma cells to mucosal sites. We conclude with a brief overview of B cells as cytokine producers and their likely functional consequences on the immune response.

  6. 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.

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

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

    1986-03-05

    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 /sup 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.

  8. B cell antigen presentation is sufficient to drive neuroinflammation in an animal model of multiple sclerosis.

    Science.gov (United States)

    Parker Harp, Chelsea R; Archambault, Angela S; Sim, Julia; Ferris, Stephen T; Mikesell, Robert J; Koni, Pandelakis A; Shimoda, Michiko; Linington, Christopher; Russell, John H; Wu, Gregory F

    2015-06-01

    B cells are increasingly regarded as integral to the pathogenesis of multiple sclerosis, in part as a result of the success of B cell-depletion therapy. Multiple B cell-dependent mechanisms contributing to inflammatory demyelination of the CNS have been explored using experimental autoimmune encephalomyelitis (EAE), a CD4 T cell-dependent animal model for multiple sclerosis. Although B cell Ag presentation was suggested to regulate CNS inflammation during EAE, direct evidence that B cells can independently support Ag-specific autoimmune responses by CD4 T cells in EAE is lacking. Using a newly developed murine model of in vivo conditional expression of MHC class II, we reported previously that encephalitogenic CD4 T cells are incapable of inducing EAE when B cells are the sole APC. In this study, we find that B cells cooperate with dendritic cells to enhance EAE severity resulting from myelin oligodendrocyte glycoprotein (MOG) immunization. Further, increasing the precursor frequency of MOG-specific B cells, but not the addition of soluble MOG-specific Ab, is sufficient to drive EAE in mice expressing MHCII by B cells alone. These data support a model in which expansion of Ag-specific B cells during CNS autoimmunity amplifies cognate interactions between B and CD4 T cells and have the capacity to independently drive neuroinflammation at later stages of disease.

  9. IL-6 contributes to an immune tolerance checkpoint in post germinal center B cells.

    Science.gov (United States)

    Yan, Yi; Wang, Ying-Hua; Diamond, Betty

    2012-02-01

    The generation of a B cell repertoire involves producing and subsequently purging autoreactive B cells. Receptor editing, clonal deletion and anergy are key mechanisms of central B cell tolerance. Somatic mutation of antigen-activated B cells within the germinal center produces a second wave of autoreactivity; but the regulatory mechanisms that operate at this phase of B cell activation are poorly understood. We recently identified a post germinal center tolerance checkpoint, where receptor editing is re-induced to extinguish autoreactivity that is generated by somatic hypermutation. Re-induction of the recombinase genes RAG1 and RAG2 in antigen-activated B cells requires antigen to engage the B cell receptor and IL-7 to signal through the IL-7 receptor. We demonstrate that this process requires IL-6 to upregulate IL-7 receptor expression on post germinal center B cells. Diminishing IL-6 by blocking antibody or haplo-insufficiency leads to reduced expression of the IL-7 receptor and RAG and increased titers of anti-DNA antibodies following immunization with a peptide mimetope of DNA. The dependence on IL-6 to initiate receptor editing is B cell intrinsic. Interestingly, estradiol decreases IL-6 expression thereby increasing the anti-DNA response. Our data reveal a novel regulatory cascade to control post germinal center B cell autoreactivity.

  10. Regulatory B cells contribute to the impaired antitumor immunity in ovarian cancer patients.

    Science.gov (United States)

    Wei, Xin; Jin, Yangqiu; Tian, Yinpu; Zhang, Huiyuan; Wu, Jie; Lu, Wei; Lu, Xiaofen

    2016-05-01

    Multiple factors in the tumor microenvironment were found to inhibit antitumor adaptive immune responses, allowing tumor persistence and growth. In this study, ascites from ovarian cancer patients were collected. We observed that a population of interleukin-10(+) B (IL-10(+) B) cells was preferentially enriched in the ascites. This population was associated with naive B cell phenotype or IgM or class-switched memory B cell phenotypes. The frequencies of IL-10(+) B cells were negatively correlated with the frequencies of interferon gamma-producing (IFN-g(+)) CD8(+) T cells and were positively correlated with the frequencies of Foxp3(+) CD4(+) T cells. To examine whether increased IL-10(+) B cells in ascites could directly result in increased suppression of IFN-g production by CD8(+) T cells, we cocultured CD8(+) T cells with autologous blood B cells or ascitic B cells and found that CD8(+) T cells cocultured with ascitic B cells demonstrated significantly suppressed IFN-g production. This suppression was in part mediated by IL-10 as well as low CD80/CD86 expression, since depletion of IL-10 and stimulation of CD28 partially reverted IL-10(+) B cell-mediated suppression. Together, these data demonstrated an additional regulatory mechanism in the tumor microenvironment, which utilizes IL-10(+) B cells.

  11. 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

    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...

  12. Antibody-Independent Function of Human B Cells Contributes to Antifungal T Cell Responses.

    Science.gov (United States)

    Li, Rui; Rezk, Ayman; Li, Hulun; Gommerman, Jennifer L; Prat, Alexandre; Bar-Or, Amit

    2017-03-08

    Fungal infections (e.g., Candida albicans) can manifest as serious medical illnesses, especially in the elderly and immune-compromised hosts. T cells are important for Candida control. Whether and how B cells are involved in antifungal immunity has been less clear. Although patients with agammaglobulinemia exhibit normal antifungal immunity, increased fungal infections are reported following B cell-depleting therapy, together pointing to Ab-independent roles of B cells in controlling such infections. To test how human B cells may contribute to fungal-associated human T cell responses, we developed a novel Ag-specific human T cell/B cell in vitro coculture system and found that human B cells could induce C. albicans-associated, MHC class II-restricted responses of naive T cells. Activated B cells significantly enhanced C. albicans-mediated Th1 and Th17 T cell responses, which were both strongly induced by CD80/CD86 costimulation. IL-6(+)GM-CSF(+) B cells were the major responding B cell subpopulation to C. albicans and provided efficient costimulatory signals to the T cells. In vivo B cell depletion in humans resulted in reduced C. albicans-associated T responses. Of note, the decreased Th17, but not Th1, responses could be reversed by soluble factors from B cells prior to depletion, in an IL-6-dependent manner. Taken together, our results implicate an Ab-independent cytokine-defined B cell role in human antifungal T cell responses. These findings may be particularly relevant given the prospects of chronic B cell depletion therapy use in lymphoma and autoimmune disease, as patients age and are exposed to serial combination therapies.

  13. B cells moderate inflammatory progression and enhance bacterial containment upon pulmonary challenge with Mycobacterium tuberculosis.

    Science.gov (United States)

    Maglione, Paul J; Xu, Jiayong; Chan, John

    2007-06-01

    Though much is known about the function of T lymphocytes in the adaptive immune response against Mycobacterium tuberculosis, comparably little is understood regarding the corresponding role of B lymphocytes. Indicating B cells as components of lymphoid neogenesis during pulmonary tuberculosis, we have identified ectopic germinal centers (GCs) in the lungs of infected mice. B cells in these pulmonary lymphoid aggregates express peanut agglutinin and GL7, two markers of GC B cells, as well as CXCR5, and migrate in response to the lymphoid-associated chemokine CXCL13 ex vivo. CXCL13 is negatively regulated by the presence of B cells, as its production is elevated in lungs of B cell-deficient (B cell(-/-)) mice. Upon aerosol with 100 CFU of M. tuberculosis Erdman, B cell(-/-) mice have exacerbated immunopathology corresponding with elevated pulmonary recruitment of neutrophils. Infected B cell(-/-) mice show increased production of IL-10 in the lungs, whereas IFN-gamma, TNF-alpha, and IL-10R remain unchanged from wild type. B cell(-/-) mice have enhanced susceptibility to infection when aerogenically challenged with 300 CFU of M. tuberculosis corresponding with elevated bacterial burden in the lungs but not in the spleen or liver. Adoptive transfer of B cells complements the phenotypes of B cell(-/-) mice, confirming a role for B cells in both modulation of the host response and optimal containment of the tubercle bacillus. As components of ectopic GCs, moderators of inflammatory progression, and enhancers of local immunity against bacterial challenge, B cells may have a greater role in the host defense against M. tuberculosis than previously thought.

  14. Bruton’s Tyrosine Kinase Promotes Persistence of Mature Anti-Insulin B Cells

    Science.gov (United States)

    Bonami, Rachel H.; Sullivan, Allison M.; Case, James B.; Steinberg, Hannah E.; Hoek, Kristen L.; Khan, Wasif N.; Kendall, Peggy L.

    2014-01-01

    Autoreactive B lymphocytes are essential for the development of T cell–mediated type 1 diabetes (T1D). Cytoplasmic Bruton’s tyrosine kinase (BTK) is a key component of B cell signaling, and its deletion in T1D-prone NOD mice significantly reduces diabetes. However, the role of BTK in the survival and function of autoreactive B cells is not clear. To evaluate the contributions of BTK, we used mice in which B cells express an anti-insulin BCR (125Tg) and promote T1D, despite being anergic. Crossing Btk deficiency onto 125Tg mice reveals that, in contrast to immature B cells, mature anti-insulin B cells are exquisitely dependent upon BTK, because their numbers are reduced by 95%. BTK kinase domain inhibition reproduces this effect in mature anti-insulin B cells, with less impact at transitional stages. The increased dependence of anti-insulin B cells on BTK became particularly evident in an Igκ locus site–directed model, in which 50% of B cells edit their BCRs to noninsulin specificities; Btk deficiency preferentially depletes insulin binders from the follicular and marginal zone B cell subsets. The persistent few Btk-deficient anti-insulin B cells remain competent to internalize Ag and invade pancreatic islets. As such, loss of BTK does not significantly reduce diabetes incidence in 125Tg/NOD mice as it does in NOD mice with a normal B cell repertoire. Thus, BTK targeting may not impair autoreactive anti-insulin B cell function, yet it may provide protection in an endogenous repertoire by decreasing the relative availability of mature autoreactive B cells. PMID:24453243

  15. Naïve and memory B cells exhibit distinct biochemical responses following BCR engagement.

    Science.gov (United States)

    Moens, Leen; Kane, Alisa; Tangye, Stuart G

    2016-09-01

    Immunological memory is characterized by the rapid reactivation of memory B cells that produce large quantities of high-affinity antigen-specific antibodies. This contrasts the response of naïve B cells, and the primary immune response, which is much slower and of lower affinity. Memory responses are critical for protection against infectious diseases and form the basis of most currently available vaccines. Although we have known about the phenomenon of long-lived memory for centuries, the biochemical differences underlying these diverse responses of naïve and memory B cells is incompletely resolved. Here we investigated the nature of B-cell receptor (BCR) signaling in human splenic naïve, IgM(+) memory and isotype-switched memory B cells following multivalent BCR crosslinking. We observed comparable rapid and transient phosphorylation kinetics for proximal (phosphotyrosine and spleen tyrosine kinase) and propagation (B-cell linker, phospholipase Cγ2) signaling components in these different B-cell subsets. However, the magnitude of activation of downstream components of the BCR signaling pathway were greater in memory compared with naïve cells. Although no differences were observed in the magnitude of Ca(2+) mobilization between subsets, IgM(+) memory B cells exhibited a more rapid Ca(2+) mobilization and a greater depletion of the Ca(2+) endoplasmic reticulum stores, while IgG(+) memory B cells had a prolonged Ca(2+) uptake. Collectively, our findings show that intrinsic signaling features of B-cell subsets contribute to the robust response of human memory B cells over naïve B cells. This has implications for our understanding of memory B-cell responses and provides a framework to modulate these responses in the setting of vaccination and immunopathologies, such as immunodeficiency and autoimmunity.

  16. Toll-like receptors regulate B cell cytokine production in patients with diabetes

    Science.gov (United States)

    Jagannathan, M.; McDonnell, M.; Liang, Y.; Hasturk, H.; Hetzel, J.; Rubin, D.; Kantarci, A.; Van Dyke, T. E.; Ganley-Leal, L. M.

    2010-01-01

    Aims/hypothesis Understanding cellular and molecular events in diabetes mellitus will identify new approaches for therapy. Immune system cells are important modulators of chronic inflammation in diabetes mellitus, but the role of B cells is not adequately studied. The aim of this work was to define the function of B cells in diabetes mellitus patients through focus on B cell responses to pattern recognition receptors. Methods We measured expression and function of Toll-like receptors (TLRs) on peripheral blood B cells from diabetes mellitus patients by flow cytometry and multiplexed cytokine analysis. We similarly analysed B cells from non-diabetic donors and periodontal disease patients as comparative cohorts. Results B cells from diabetes mellitus patients secrete multiple pro-inflammatory cytokines, and IL-8 production is significantly elevated in B cells from diabetic patients compared with those from non-diabetic individuals. These data, plus modest elevation of TLR surface expression, suggest B cell IL-8 hyperproduction is a cytokine-specific outcome of altered TLR function in B cells from diabetes mellitus patients. Altered TLR function is further evidenced by demonstration of an unexpected, albeit modest ‘anti-inflammatory’ function for TLR4. Importantly, B cells from diabetes mellitus patients fail to secrete IL-10, an anti-inflammatory cytokine implicated in inflammatory disease resolution, under a variety of TLR-stimulating conditions. Comparative analyses of B cells from patients with a second chronic inflammatory disease, periodontal disease, indicated that some alterations in B cell TLR function associate specifically with diabetes mellitus. Conclusions/interpretation Altered TLR function in B cells from diabetes mellitus patients increases inflammation by two mechanisms: elevation of pro-inflammatory IL-8 and lack of anti-inflammatory/protective IL-10 production. PMID:20383694

  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. B cell-specific lentiviral gene therapy leads to sustained B-cell functional recovery in a murine model of X-linked agammaglobulinemia.

    Science.gov (United States)

    Kerns, Hannah M; Ryu, Byoung Y; Stirling, Brigid V; Sather, Blythe D; Astrakhan, Alexander; Humblet-Baron, Stephanie; Liggitt, Denny; Rawlings, David J

    2010-03-18

    The immunodeficiency disorder, X-linked agammaglobulinemia (XLA), results from mutations in the gene encoding Bruton tyrosine kinase (Btk). Btk is required for pre-B cell clonal expansion and B-cell antigen receptor signaling. XLA patients lack mature B cells and immunoglobulin and experience recurrent bacterial infections only partially mitigated by life-long antibody replacement therapy. In pursuit of definitive therapy for XLA, we tested ex vivo gene therapy using a lentiviral vector (LV) containing the immunoglobulin enhancer (Emu) and Igbeta (B29) minimal promoter to drive B lineage-specific human Btk expression in Btk/Tec(-/-) mice, a strain that reproduces the features of human XLA. After transplantation of EmuB29-Btk-LV-transduced stem cells, treated mice showed significant, albeit incomplete, rescue of mature B cells in the bone marrow, peripheral blood, spleen, and peritoneal cavity, and improved responses to T-independent and T-dependent antigens. LV-treated B cells exhibited enhanced B-cell antigen receptor signaling and an in vivo selective advantage in the peripheral versus central B-cell compartment. Secondary transplantation showed sustained Btk expression, viral integration, and partial functional responses, consistent with long-term stem cell marking; and serial transplantation revealed no evidence for cellular or systemic toxicity. These findings strongly support pursuit of B lineage-targeted LV gene therapy in human XLA.

  19. CD19 CAR-targeted T cells induce long-term remission and B Cell Aplasia in an immunocompetent mouse model of B cell acute lymphoblastic leukemia.

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    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.

  20. TGFβ activated kinase 1 (TAK1 at the crossroad of B cell receptor and Toll-like receptor 9 signaling pathways in human B cells.

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    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.

  1. Accumulation of self-reactive naive and memory B cell reveals sequential defects in B cell tolerance checkpoints in Sjogren's syndrome.

    Directory of Open Access Journals (Sweden)

    Elisa Corsiero

    Full Text Available Sjögren's syndrome (SS is an autoimmune disease characterised by breach of self-tolerance towards nuclear antigens resulting in high affinity circulating autoantibodies. Although peripheral B cell disturbances have been described in SS, with predominance of naïve and reduction of memory B cells, the stage at which errors in B cell tolerance checkpoints accumulate in SS is unknown. Here we determined the frequency of self- and poly-reactive B cells in the circulating naïve and memory compartment of SS patients. Single CD27-IgD+ naïve, CD27+IgD+ memory unswitched and CD27+IgD- memory switched B cells were sorted by FACS from the peripheral blood of 7 SS patients. To detect the frequency of polyreactive and autoreactive clones, paired Ig VH and VL genes were amplified, cloned and expressed as recombinant monoclonal antibodies (rmAbs displaying identical specificity of the original B cells. IgVH and VL gene usage and immunoreactivity of SS rmAbs were compared with those obtained from healthy donors (HD. From a total of 353 VH and 293 VL individual sequences, we obtained 114 rmAbs from circulating naïve (n = 66 and memory (n = 48 B cells of SS patients. Analysis of the Ig V gene repertoire did not show significant differences in SS vs. HD B cells. In SS patients, circulating naïve B cells (with germline VH and VL genes displayed a significant accumulation of clones autoreactive against Hep-2 cells compared to HD (43.1% vs. 25%. Moreover, we demonstrated a progressive increase in the frequency of circulating anti-nuclear naïve (9.3%, memory unswitched (22.2% and memory switched (27.3% B cells in SS patients. Overall, these data provide novel evidence supporting the existence of both early and late defects in B cell tolerance checkpoints in patients with SS resulting in the accumulation of autoreactive naïve and memory B cells.

  2. Prognostic Significance of B-cell Differentiation Genes Encoding Proteins in Diffuse Large B-cell Lymphoma and Follicular Lymphoma Grade 3

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    Borovečki, Ana; Korać, Petra; Nola, Marin; Ivanković, Davor; Jakšić, Branimir; Dominis, Mara

    2008-01-01

    Aim To define prognostic significance of B-cell differentiation genes encoding proteins and BCL2 and BCL6 gene abnormalities in diffuse large B-cell lymphoma and follicular lymphoma grade 3 with >75% follicular growth pattern. Methods In 53 patients with diffuse large B-cell lymphoma and 20 patients with follicular lymphoma grade 3 with >75% follicular growth pattern the following was performed: 1) determination of protein expression of BCL6, CD10, MUM1/IRF4, CD138, and BCL2 by immunohistochemistry; 2) subclassification into germinal center B-cell-like (GCB) and activated B-cell-like (ABC) groups according to the results of protein expression; 3) detection of t(14;18)(q32;q21)/IgH-BCL2 and BCL6 abnormalities by fluorescent in situ hybridization in diffuse large B-cell lymphoma and follicular lymphoma grade 3 with >75% follicular growth pattern as well as in GCB and ABC groups; and 4) assessment of the influence of the analyzed characteristics and clinical prognostic factors on overall survival. Results Isolated BCL6 expression was more frequently found in follicular lymphoma grade 3 with >75% follicular growth pattern than in diffuse large B-cell lymphoma (P = 0.030). There were no differences in BCL2 and BCL6 gene abnormalities between diffuse large B-cell lymphoma and follicular lymphoma grade 3 with >75% follicular growth pattern. Diffuse large B-cell lymphoma and follicular lymphoma grade 3 with >75% follicular growth pattern patients were equally distributed in GCB and ABC groups. t(14;18)(q32;q21) was more frequently recorded in GCB group, and t(14;18)(q32;q21) with BCL2 additional signals or only BCL2 and IgH additional signals in ABC group (P = 0.004). The GCB and ABC groups showed no difference in BCL6 gene abnormalities. There was no overall survival difference between the patients with diffuse large B-cell lymphoma or follicular lymphoma grade 3 with >75% follicular growth pattern, however, GCB group had longer overall survival than ABC group (P

  3. Feasibility and Outcome of Haploidentical Hematopoietic Stem Cell Transplantation with Post-Transplant High-Dose Cyclophosphamide for Children and Adolescents with Hematologic Malignancies: An AIEOP-GITMO Retrospective Multicenter Study.

    Science.gov (United States)

    Berger, Massimo; Lanino, Edoardo; Cesaro, Simone; Zecca, Marco; Vassallo, Elena; Faraci, Maura; De Bortoli, Massimiliano; Barat, Veronica; Prete, Arcangelo; Fagioli, Franca

    2016-05-01

    Post-transplant high-dose cyclophosphamide (PTCy) is a novel approach to prevent graft-versus-host disease (GVHD) and rejection in patients given haploidentical hematopoietic stem cell transplantation (HSCT). Thirty-three patients with high-risk hematologic malignancies and lacking a match-related or -unrelated donor were treated with PTCy haploidentical HSCT in 5 Italian AIEOP centers. Nineteen patients had a nonmyeloablative preparative regimen (57%), and 14 patients received a full myeloablative conditioning regimen (43%). No patients received serotherapy; GVHD prophylaxis was based on PTCy (50 mg/kg on days +3 and +4) combined with mycophenolate plus tacrolimus or cyclosporine A. Neutrophil and platelet engraftment was achieved on days +17 (range, 14 to 37) and +27 (range, 16 to 71). One patient had autologous reconstitution for anti-HLA antibodies. Acute GVHD grades II to IV and III to IV and chronic GVHD developed in 22% (95% CI, 11 to 42), 3% (95% CI, 0 to 21), and 4% (95% CI, 0 to 27) of cases, respectively. The 1-year overall survival rate was 72% (95% CI, 56 to 88), progression-free survival rate was 61% (95% CI, 43 to 80), cumulative incidence of relapse was 24% (95% CI, 13 to 44), and transplant-related mortality was 9% (95% CI, 3 to 26). The univariate analysis for risk of relapse incidence showed how 3 significant variables, mother as donor (P = .02), donor gender as female (P = .04), and patient gender as female (P = .02), were significantly associated with a lower risk of relapse. Disease progression was the main cause of death. PTCy is a safe procedure also for children and adolescents who have already received several lines of chemotherapy. Among the different diseases, a trend for better 1-year rates of overall survival was obtained for nonacute leukemia patients.

  4. Signaling Proteins and Transcription Factors in Normal and Malignant Early B Cell Development

    Directory of Open Access Journals (Sweden)

    Patricia Pérez-Vera

    2011-01-01

    Full Text Available B cell development starts in bone marrow with the commitment of hematopoietic progenitors to the B cell lineage. In murine models, the IL-7 and preBCR receptors, and the signaling pathways and transcription factors that they regulate, control commitment and maintenance along the B cell pathway. E2A, EBF1, PAX5, and Ikaros are among the most important transcription factors controlling early development and thereby conditioning mice homeostatic B cell lymphopoiesis. Importantly, their gain or loss of function often results in malignant development in humans, supporting conserved roles for these transcription factors. B cell acute lymphoblastic leukemia is the most common cause of pediatric cancer, and it is characterized by unpaired early B cell development resulting from genetic lesions in these critical signaling pathways and transcription factors. Fine mapping of these genetic abnormalities is allowing more specific treatments, more accurately predicting risk profiles for this disease, and improving survival rates.

  5. A switch from canonical to noncanonical autophagy shapes B cell responses.

    Science.gov (United States)

    Martinez-Martin, Nuria; Maldonado, Paula; Gasparrini, Francesca; Frederico, Bruno; Aggarwal, Shweta; Gaya, Mauro; Tsui, Carlson; Burbage, Marianne; Keppler, Selina Jessica; Montaner, Beatriz; Jefferies, Harold B J; Nair, Usha; Zhao, Yan G; Domart, Marie-Charlotte; Collinson, Lucy; Bruckbauer, Andreas; Tooze, Sharon A; Batista, Facundo D

    2017-02-10

    Autophagy is important in a variety of cellular and pathophysiological situations; however, its role in immune responses remains elusive. Here, we show that among B cells, germinal center (GC) cells exhibited the highest rate of autophagy during viral infection. In contrast to mechanistic target of rapamycin complex 1-dependent canonical autophagy, GC B cell autophagy occurred predominantly through a noncanonical pathway. B cell stimulation was sufficient to down-regulate canonical autophagy transiently while triggering noncanonical autophagy. Genetic ablation of WD repeat domain, phosphoinositide-interacting protein 2 in B cells alone enhanced this noncanonical autophagy, resulting in changes of mitochondrial homeostasis and alterations in GC and antibody-secreting cells. Thus, B cell activation prompts a temporal switch from canonical to noncanonical autophagy that is important in controlling B cell differentiation and fate.

  6. 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 candidate for such regulation could be the chemokine CXCL10. CXCL10 is mainly produced by human monocytes, but a few reports have also found CXCL10 production by human B cells. The objective of this study was to investigate CXCL10 production by human B cells in response to in vitro stimulation with Mtb...... antigens. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed human blood samples from 30 volunteer donors using multiparameter flow cytometry, and identified a subgroup of B cells producing CXCL10 in response to in vitro stimulation with antigens. T cells did not produce CXCL10, but CXCL10 production by B cells...

  7. Microbial Translocation and B Cell Dysfunction in Human Immunodeficiency Virus Disease

    Directory of Open Access Journals (Sweden)

    Wei Jiang

    2012-01-01

    Full Text Available The gut mucosal barrier disrupted in HIV disease, resulting in increased systemic exposure to microbial products such as Lipo Polys Accharide (LPS. The association of enhanced microbial translocation and B cell dysfunction in HIV disease is not fully understood. High dose and short term exposure of microbial Toll-Like Receptor (TLR agonists were used as vaccine adjuvants, however, low dose and long term exposure of TLR agonists could be harmful. The characteristics of B cell dysfunction in HIV disease included B cell, especially memory B cell depletion, enhanced levels of autoimmune antibodies and impaired vaccine or antigen responsiveness. This review discusses and explores the possibility of the effect of microbial translocation on memory B cell depletion and impaired vaccine responses in HIV infection. By determining the mechanisms of B cell depletion and perturbations in HIV disease, it may be possible to design interventions that can improve immune responses to vaccines, reduce selected opportunistic infections and perhaps slow disease progression.

  8. [Insulin pump in type 2 diabetes: B-cell focused treatment].

    Science.gov (United States)

    Picková, Klára; Rušavý, Zdeněk

    2017-01-01

    Type 2 diabetes is a disorder characterized by insulin resistance and progressive deterioration of B-cell insulin secretion. B-cell protective strategies for lowering glucolipotoxicity by rapid achievement of normoglycemia using exogenous insulin improve their function and prolong diabetes remission. Insulin pump is an effective treatment method in newly diagnosed diabetes, where even short-term pump therapy is B-cell protective. Combination therapy with insulin pump and antidiabetics targeting the incretin system acts in synergy to protect the B-cell. While the positive effect of insulin pump is apparent even a year after stopping the therapy, the effect of incretins lasts only while on the medication. Short-term insulin treatment, especially delivered by insulin pump, is an effective method of B-cell protection in recent type 2 diabetes.Key words: B-cell function - diabetes mellitus - insulin pump - insulin resistance - type 2 diabetes.

  9. Expression of Bruton's tyrosine kinase in B-cell neoplasms evaluated by flow cytometry.

    Science.gov (United States)

    Marcondes, Natália Aydos; Fernandes, Flavo Beno; Alegretti, Ana Paula; Faulhaber, Gustavo Adolpho Moreira

    2016-12-27

    Bruton's tyrosine kinase (BTK) is a cytoplasmatic protein that is part of the B-cell antigen receptor signaling pathway. Our aim was to evaluate the expression of BTK in B-cell neoplasms and compare it to normal B-cell lymphocytes. After surface staining with CD19 and CD45, flow cytometry staining for intracellular BTK was performed in leukemic or mature B-cells from bone marrow or peripheral blood samples. No differences in BTK expression were identified between groups, or in comparison to control samples, there was no association between BTK expression and the clinical variables evaluated. BTK expression in B-cell neoplasms was similar to that of normal B-cell lymphocytes.

  10. Targeting Bruton's tyrosine kinase signaling as an emerging therapeutic agent of B-cell malignancies.

    Science.gov (United States)

    Xia, Bing; Qu, Fulian; Yuan, Tian; Zhang, Yizhuo

    2015-12-01

    It is becoming increasingly evident that B-cell receptor (BCR) signaling is central to the development and function of B cells. BCR signaling has emerged as a pivotal pathway and a key driver of numerous B-cell lymphomas. Disruption of BCR signaling can be lethal to malignant B cells. Recently, kinase inhibitors that target BCR signaling have induced notable clinical responses. These inhibitors include spleen tyrosine kinase, mammalian target of rapamycin, phosphoinositide 3'-kinase and Bruton's tyrosine kinase (BTK). Ibrutinib, an oral irreversible BTK inhibitor, has emerged as a promising targeted therapy for patients with B-cell malignancies. The present review discusses the current understanding of BTK-mediated BCR signaling in the biology and pathobiology of normal and malignant B cells, and the cellular interaction with the tumor microenvironment. The data on ibrutinib in the preclinical and clinical settings is also discussed, and perspectives for the future use of ibrutinib are outlined.

  11. Rehabilitation or the death penalty: autoimmune B cells in the dock.

    Science.gov (United States)

    Dahal, Lekh N; Cragg, Mark S

    2015-03-01

    CD20-based monoclonal antibodies have become established as treatments for lymphoma, rheumatoid arthritis, systemic lupus erythematosus, vasculitis and dermatomyositis, with the principle therapeutic mechanism relating to B-cell depletion through effector cell engagement. An article by Brühl et al. in this issue of the European Journal of Immunology [Eur. J. Immunol. 2015. 45: 705-715] reveals a fundamentally distinct mechanism of silencing autoimmune B-cell responses. Rather than B-cell depletion, the authors use anti-CD79b antibodies to induce B-cell tolerance and suppress humoral immune responses against collagen to prevent the development of arthritis in mice. Here we highlight the differences in the mechanisms used by anti-CD20 and anti-CD79b Ab therapy and discuss why depletion of B cells may not be required to treat autoimmune arthritis and other B-cell-associated pathologies.

  12. 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.

  13. Epigenomic evolution in diffuse large B-cell lymphomas.

    Science.gov (United States)

    Pan, Heng; Jiang, Yanwen; Boi, Michela; Tabbò, Fabrizio; Redmond, David; Nie, Kui; Ladetto, Marco; Chiappella, Annalisa; Cerchietti, Leandro; Shaknovich, Rita; Melnick, Ari M; Inghirami, Giorgio G; Tam, Wayne; Elemento, Olivier

    2015-04-20

    The contribution of epigenomic alterations to tumour progression and relapse is not well characterized. Here we characterize an association between disease progression and DNA methylation in diffuse large B-cell lymphoma (DLBCL). By profiling genome-wide DNA methylation at single-base pair resolution in thirteen DLBCL diagnosis-relapse sample pairs, we show that DLBCL patients exhibit heterogeneous evolution of tumour methylomes during relapse. We identify differentially methylated regulatory elements and determine a relapse-associated methylation signature converging on key pathways such as transforming growth factor-β (TGF-β) receptor activity. We also observe decreased intra-tumour methylation heterogeneity from diagnosis to relapsed tumour samples. Relapse-free patients display lower intra-tumour methylation heterogeneity at diagnosis compared with relapsed patients in an independent validation cohort. Furthermore, intra-tumour methylation heterogeneity is predictive of time to relapse. Therefore, we propose that epigenomic heterogeneity may support or drive the relapse phenotype and can be used to predict DLBCL relapse.

  14. Hypogammaglobulinaemia in low grade B cell tumours; significance and therapy.

    Science.gov (United States)

    Chapel, H; Griffiths, H; Brennan, V; Bunch, C; Lea, J; Lee, M

    1991-04-01

    Bacterial infection is an important cause of morbidity and mortality in patients with B-cell tumors; this is related to their secondary hypogammaglobulinaemia. Two studies of intravenous replacement therapy [IVIg] have been performed in such patients: a crossover study over two years and a randomised, multicentre study over one year. Both involved infusions of IVIg [400 mg/Kg] or an equivalent volume of saline every three weeks for one year. In both studies, serious bacterial infections were considerably reduced by IVIg. Viral and fungal infections were uncommon. In the crossover study bacterial infections were more frequent in periods in which patients serum IgG levels were below the normal range [less than 6.4 g/l]. The sites of bacterial infection were similar in these studies to those in previously published reports, namely respiratory tract, skin, urinary tract and blood. There were a few mild adverse reactions which were related to the rate of infusion, but no serious toxic effects. Haematological parameters were not significantly changed by IVIg at this dose and disease progression did not appear to be changed.

  15. Cerebral infratentorial large B-cell lymphoma presenting as Parkinsonism.

    Science.gov (United States)

    Lin, Chih-Ming; Hong, Kelvin

    2010-03-01

    Though rare, primary intracranial tumors can present with Parkinsonian symptoms, and diagnosis can be delayed unless there is a high index of suspicion. We herein present an 81-year-old man who was seen in our neurology clinic due to acute onset of unsteady gait and altered consciousness. Parkinsonism was initially diagnosed because of the typical manifestations. Levodopa was prescribed; however, there was a limited effect on his symptoms. Upon detail history and neurological examination, left sided hemiparesis was disclosed. Cerebral imaging studies revealed a solid mass over the right infratentorial para-midbrain area leading to reactive obstructive hydrocephalus. Work-up including chest and abdominal CT scanning, upper and lower GI endoscopy, and tumor marker studies failed to uncover any abnormalities. A neurosurgeon was consulted and a shunt procedure and biopsy of the infratentorial mass were performed. Histopathological examination of the biopsy tissue revealed tumor diffusely intermixed with large cells consistent with large B-cell lymphoma. The patient and his family declined further treatment. Though rare, cerebral tumors can present with Parkinsonian features and represent a diagnostic challenge. Clinicians should be aware of the possibility of cerebral neoplasms causing Parkinsonism, and include them in the differential diagnosis, especially for patients presenting with atypical Parkinsonian features, or those not responsive to initial therapy.

  16. Primary Mediastinal Large B-Cell Lymphoma during Pregnancy

    Directory of Open Access Journals (Sweden)

    Cesar A. Perez

    2012-01-01

    Full Text Available Non-Hodgkin’s Lymphoma (NHL rarely presents during pregnancy and primary mediastinal large B-cell lymphoma (PMLBCL accounts for approximately 2.5% of patients with NHL. The case of a 22-year-old woman who was diagnosed with Stage IIA PMLBCL during week 13 of her intrauterine pregnancy is described. The staging consisted in computed tomography (CT of the chest and magnetic resonance imaging (MRI of the abdomen and pelvis. She was managed with R-CHOP regimen (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone for a total of six cycles and, because of the early presentation during the second trimester, she received the entire chemotherapy course during the pregnancy. She delivered a healthy baby at 34 weeks of pregnancy and a 18FDG-PET/CT scan demonstrated complete remission after delivery. After 20 months of follow up she remains with no evidence of disease and her 1-year-old son has shown no developmental delays or physical abnormalities. PMLBCL, although an uncommon subgroup of DLBCL, may present during pregnancy and R-CHOP should be considered as one suitable option in this complex scenario.

  17. Prognostic Assessment in Patients with Indolent B-Cell Lymphomas

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    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.

  18. 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.

  19. Primary cutaneous B-cell lymphoma: Role of surgery

    Science.gov (United States)

    Parbhakar, Sam; Cin, Arianna Dal

    2011-01-01

    PURPOSE: To evaluate the role of surgery in patients diagnosed with primary cutaneous B-cell lymphoma (PCBCL) – a rare disease entity. The authors offer a rationale for the use of primary surgical excision in the treatment of isolated cutaneous lymphomas. METHODS: A literature review examining the use of primary surgical excision in the treatment of PCBCL was conducted. The lymphoma database at the Juravinski Cancer Centre (Hamilton, Ontario) was searched from January 1995 to July 2008, generating a list of 4924 patients. A simulated computer program was subsequently designed to search for all possible PCBCLs. A retrospective chart review was then conducted on the new list of 1325 patients, identifying 25 patients diagnosed with PCBCL. RESULTS: The mean age of the 25 patients with PCBCL was 59.9 years; nine (36%) were treated with surgery, and sixteen (64%) with radiation. The average follow-up period for patients was 3.6 years. Twenty-four of the 25 patients were completely cured, with only one patient recurring in the radiation subgroup. There were no complications in the surgery subgroup. There were two local complications in the radiation subgroup consisting of chronic ulcerations. CONCLUSIONS: Primary surgical excision is an effective management option in the treatment of PCBCL, particularly the marginal zone and follicle centre subtypes. PMID:22654537

  20. Systemic Sclerosis Patients Present Alterations in the Expression of Molecules Involved in B-Cell Regulation.

    Science.gov (United States)

    Soto, Lilian; Ferrier, Ashley; Aravena, Octavio; Fonseca, Elianet; Berendsen, Jorge; Biere, Andrea; Bueno, Daniel; Ramos, Verónica; Aguillón, Juan Carlos; Catalán, Diego

    2015-01-01

    The activation threshold of B cells is tightly regulated by an array of inhibitory and activator receptors in such a way that disturbances in their expression can lead to the appearance of autoimmunity. The aim of this study was to evaluate the expression of activating and inhibitory molecules involved in the modulation of B cell functions in transitional, naive, and memory B-cell subpopulations from systemic sclerosis patients. To achieve this, blood samples were drawn from 31 systemic sclerosis patients and 53 healthy individuals. Surface expression of CD86, MHC II, CD19, CD21, CD40, CD22, Siglec 10, CD35, and FcγRIIB was determined by flow cytometry. IL-10 production was evaluated by intracellular flow cytometry from isolated B cells. Soluble IL-6 and IL-10 levels were measured by ELISA from supernatants of stimulated B cells. Systemic sclerosis patients exhibit an increased frequency of transitional and naive B cells related to memory B cells compared with healthy controls. Transitional and naive B cells from patients express higher levels of CD86 and FcγRIIB than healthy donors. Also, B cells from patients show high expression of CD19 and CD40, whereas memory cells from systemic sclerosis patients show reduced expression of CD35. CD19 and CD35 expression levels associate with different autoantibody profiles. IL-10(+) B cells and secreted levels of IL-10 were markedly reduced in patients. In conclusion, systemic sclerosis patients show alterations in the expression of molecules involved in B-cell regulation. These abnormalities may be determinant in the B-cell hyperactivation observed in systemic sclerosis.

  1. Further evidence for a human B cell activating factor distinct from IL-4.

    Science.gov (United States)

    Diu, A; Février, M; Mollier, P; Charron, D; Banchereau, J; Reinherz, E L; Thèze, J

    1990-01-01

    Supernatants from activated human T cell clones were previously shown to contain B cell-activating factor (BCAF), an activity which results in polyclonal resting B cell stimulation. In the present study, we investigate the relationship between this activity and human interleukin-4 which was also shown to act on resting B cells. The supernatant of the T cell clone TT9 contains IL-4 but anti-IL-4 antiserum does not affect the response of B cells as measured by thymidine uptake or cell volume increase. Furthermore, IL-4 induces Fc epsilon-receptor (CD23) expression on 30% of unstimulated human B cells, whereas BCAF-containing supernatants from clone P2, that do not contain detectable amounts of IL-4, promote B cell proliferation without inducing CD23 expression. Our results therefore establish that IL-4 and BCAF are distinct activities and suggest that they trigger different activation pathways in human B cells. In addition, culture of B cells with T cell supernatants for 72 hr induces a three- to fourfold increase in the expression of HLA-DR, -DP, and -DQ antigens in 50% of B cells. The addition of inhibiting concentrations of anti-IFN-gamma, LT, or IL-4 antisera to the cultures does not change these results. Finally, 30% of B cells cultured with T cell supernatants leave the G1 phase of the cell cycle and 20% reach mitosis. Taken together, our findings further support the existence of a B cell-activating factor responsible for the activation of resting human B cells.

  2. Systemic sclerosis patients present alterations in the expression of molecules involved in B cell regulation

    Directory of Open Access Journals (Sweden)

    Lilian eSoto

    2015-09-01

    Full Text Available The activation threshold of B cells is tightly regulated by an array of inhibitory and activator receptors, in such a way that disturbances in their expression can lead to the appearance of autoimmunity. The aim of this study was to evaluate the expression of activating and inhibitory molecules involved in the modulation of B cell functions in transitional, naïve and memory B cell sub-populations from systemic sclerosis patients. To achieve this, blood samples were drawn from thirty one systemic sclerosis patients and fifty three healthy individuals. Surface expression of CD86, MHC II, CD19, CD21, CD40, CD22, Siglec 10, CD35, and FcgammaRIIB was determined by flow cytometry. IL-10 production was evaluated by intracellular flow cytometry from isolated B cells. Soluble IL-6 and IL-10 levels were measured by ELISA from supernatants of stimulated B cells. Systemic sclerosis patients exhibit an increased frequency of transitional and naïve B cells related to memory B cells, compared to healthy controls. Transitional and naïve B cells from patients express higher levels of CD86 and FcgammaRIIB than healthy donors. Also, B cells from patients show high expression of CD19 and CD40, while memory cells from systemic sclerosis patients show reduced expression of CD35. CD19 and CD35 expression levels associate to different autoantibody profiles. IL-10+ B cells and secreted levels of IL-10 were markedly reduced in patients. In conclusion, systemic sclerosis patients show alterations in the expression of molecules involved in B cell regulation. These abnormalities may be determinant in the B cell hyperactivation observed in systemic sclerosis.

  3. Mitochondrial function provides instructive signals for activation-induced B-cell fates.

    OpenAIRE

    Jang, Kyoung-Jin; Mano, Hiroto; Aoki, Koji; Hayashi, Tatsunari; Muto, Akihiko; Nambu, Yukiko; Takahashi, Katsu; Itoh, Katsuhiko; Taketani, Shigeru; Stephen L Nutt; Igarashi, Kazuhiko; Shimizu, Akira; Sugai, Manabu

    2015-01-01

    During immune reactions, functionally distinct B-cell subsets are generated by stochastic processes, including class-switch recombination (CSR) and plasma cell differentiation (PCD). In this study, we show a strong association between individual B-cell fates and mitochondrial functions. CSR occurs specifically in activated B cells with increased mitochondrial mass and membrane potential, which augment mitochondrial reactive oxygen species (mROS), whereas PCD occurs in cells with decreased mit...

  4. Burkitt's lymphoma is a malignancy of mature B cells expressing somatically mutated V region genes.

    OpenAIRE

    Klein, U.; Klein, G.; Ehlin-Henriksson, B.; Rajewsky, K.; Küppers, R.

    1995-01-01

    BACKGROUND: The developmental stage from which stems the malignant B cell population in Burkitt's lymphoma (BL) is unclear. An approach to answering this question is provided by the sequence analysis of rear-ranged immunoglobulin (Ig) variable region (V) genes from BL for evidence of somatic mutations, together with a phenotypic characterization. As somatic hypermutation of Ig V region genes occurs in germinal center B cells, somatically mutated Ig genes are found in germinal center B cells a...

  5. Reconstituted B cell receptor signaling reveals carbohydrate-dependent mode of activation

    OpenAIRE

    2016-01-01

    Activation of immune cells (but not B cells) with lectins is widely known. We used the structurally defined interaction between influenza hemagglutinin (HA) and its cell surface receptor sialic acid (SA) to identify a B cell receptor (BCR) activation modality that proceeded through non-cognate interactions with antigen. Using a new approach to reconstitute antigen-receptor interactions in a human reporter B cell line, we found that sequence-defined BCRs from the human germline repertoire coul...

  6. B cells as multi-functional players during Mycobacterium tuberculosis infection and disease.

    Science.gov (United States)

    du Plessis, Willem J; Walzl, Gerhard; Loxton, André G

    2016-03-01

    Immunity to tuberculosis is still understood to be driven and maintained by T-cell derived immune responses. With a steady influx of data, it is becoming clear that B cells, the mediators of humoral immunity, have the capacity to function in roles not previously appreciated within the traditional B cell dogma. In this review we aim to discuss B cells, from its generation through to its functioning as effectors in both the innate and adaptive immune response, within the tuberculosis domain.

  7. Disodium cromoglycate enhances ongoing immunoglobulin production in vitro in human B cells.

    Science.gov (United States)

    Kimata, H; Yoshida, A; Ishioka, C; Mikawa, H

    1991-01-01

    The effect of disodium cromoglycate (DSCG) upon human immunoglobulin (Ig) isotypes and IgG subclasses production by purified B cells was studied. DSCG enhanced IgM, IgG1, IgG2, IgG3, IgG4 and IgA production in a dose-dependent fashion, while DSCG failed to induce IgE production at any concentrations tested by purified B cells. When B cells were separated into small resting and large activated B cells, DSCG failed to induce Ig production from small resting B cells in the presence or absence of Staphylococcus aureus Cowan strain I (SAC). In contrast, in large activated B cells DSCG significantly enhanced all types of Ig production (two-to threefold), especially IgG4 production (seven-to 11-fold), except IgE, which large B cells did not produce. The enhancement of IgG subclass production was not subclass switching, since DSCG failed to enhance IgG1 production in B cells depleted of surface IgG1+ cells (sIgG1+ cells). Similarly, DSCG did not enhance IgG2, IgG3 or IgG4 production from sIgG2-, sIgG3- or sIgG4- B cells, respectively, Interleukin-4 (IL-4) or interleukin-6 (IL-6) also enhanced Ig production except IgG4 from large activated B cells. The enhancing effect of DSCG was not mediated by IL-4 or IL-6 since anti-IL-4 or anti-IL-6 antibody failed to block the DSCG-induced enhancement. DSCG also enhanced IgG2 and IgM production from human B-cell lines GM-1500 and CBL, respectively. These results suggest that DSCG directly and preferentially stimulates activated B cells which are producing Ig and, in addition, enhances their Ig production. PMID:1904400

  8. Uptake and presentation of myelin basic protein by normal human B cells.

    Directory of Open Access Journals (Sweden)

    Marie Klinge Brimnes

    Full Text Available B cells may play both pathogenic and protective roles in T-cell mediated autoimmune diseases such as multiple sclerosis (MS. These functions relate to the ability of B cells to bind and present antigens. Under serum-free conditions we observed that 3-4% of circulating B cells from healthy donors were capable of binding the MS-associated self-antigen myelin basic protein (MBP and of presenting the immunodominant peptide MBP85-99, as determined by staining with the mAb MK16 recognising the peptide presented by HLA-DR15-positive cells. In the presence of serum, however, the majority of B cells bound MBP in a complement-dependent manner, and almost half of the B cells became engaged in presentation of MBP85-99. Even though complement receptor 1 (CR1, CD35 and CR2 (CD21 both contributed to binding of MBP to B cells, only CR2 was important for the subsequent presentation of MBP85-99. A high proportion of MBP85-99 presenting B cells expressed CD27, and showed increased expression of CD86 compared to non-presenting B cells. MBP-pulsed B cells induced a low frequency of IL-10-producing CD4+ T cells in 3 out of 6 donors, indicating an immunoregulatory role of B cells presenting MBP-derived peptides. The mechanisms described here refute the general assumption that B-cell presentation of self-antigens requires uptake via specific B-cell receptors, and may be important for maintenance of tolerance as well as for driving T-cell responses in autoimmune diseases.

  9. Cellular Dynamics of Memory B Cell Populations: IgM+ and IgG+ Memory B Cells Persist Indefinitely as Quiescent Cells.

    Science.gov (United States)

    Jones, Derek D; Wilmore, Joel R; Allman, David

    2015-11-15

    Despite their critical role in long-term immunity, the life span of individual memory B cells remains poorly defined. Using a tetracycline-regulated pulse-chase system, we measured population turnover rates and individual t1/2 of pre-established Ag-induced Ig class-switched and IgM-positive memory B cells over 402 d. Our results indicate that, once established, both IgG-positive and less frequent IgM-positive memory populations are exceptionally stable, with little evidence of attrition or cellular turnover. Indeed, the vast majority of cells in both pools exhibited t1/2 that appear to exceed the life span of the mouse, contrasting dramatically with mature naive B cells. These results indicate that recall Ab responses are mediated by stable pools of extremely long-lived cells, and suggest that Ag-experienced B cells employ remarkably efficient survival mechanisms.

  10. Cellular dynamics of memory B cell populations: IgM+ and IgG+ memory B cells persist indefinitely as quiescent cells1

    Science.gov (United States)

    Jones, Derek D.; Wilmore, Joel R.; Allman, David

    2015-01-01

    Despite their critical role in long-term immunity, the lifespan of individual memory B cells remains poorly defined. Using a tetracycline-regulated pulse-chase system, we measured population turnover rates and individual half-lives of pre-established antigen-induced immunoglobulin (Ig) class-switched and IgM-positive memory B cells over 402 days. Our results indicate that, once established, both IgG-positive and less frequent IgM-positive memory populations are exceptionally stable, with little evidence of attrition or cellular turnover. Indeed, the vast majority of cells in both pools exhibited half-lives that appear to exceed the lifespan of the mouse, contrasting dramatically with mature naïve B cells. These results indicate that recall antibody responses are mediated by stable pools of extremely long-lived cells, and suggest that antigen-experienced B cells employ remarkably efficient survival mechanisms. PMID:26438523

  11. B-CELL SUBPOPULATIONS OF PERIPHERAL BLOOD IN SYSTEMIC LUPUS ERYTHEMATOSUS

    Directory of Open Access Journals (Sweden)

    A. I. Budkova

    2017-01-01

    Full Text Available Distinct changes of B-cell subpopulations are observed in most systemic rheumatic diseases associated with polyclonal B cell hyperreactivity. Immunosuppressive and cytostatic therapy may also differentially influence B lymphocyte subsets in these. We studied subpopulations of B cells in systemic rheumatic patients along treatment with cytostatics. We analyzed B cell phenotypes in ninety-nine blood samples from the patients with systemic lupus erythematosus (SLE, n = 25, systemic sclerosis (n = 27, Sjogren’s syndrome (n = 47 in the course of their hospital treatment. Control group consisted of 49 healthy blood donors. Phenotyping of blood B-cell subpopulations was performed by means of flow cytometry (Beckman Coulter, USA. Naïve B-cell subpopulations in SLE patients who underwent cyclophosphan treatment, were underrepresented, if compared with normal control group, whereas plasmablast levels were increased irrespectively of medication mode. B cell population exhibits a natural heterogeneity, thus making it necessary to analyze distinct B cell subpopulations as independent functional units, when studying different rheumatic diseases. The levels of plasmablasts which are active antibody producers, remain high, despite immunosuppressive therapy performed in SLE. Thus, therapy targeted against certain B cell subsets, could be able to provide a more effective treatment for the patients with systemic rheumatic diseases.

  12. B cell maturation antigen deficiency exacerbates lymphoproliferation and autoimmunity in murine lupus.

    Science.gov (United States)

    Jiang, Chao; Loo, William M; Greenley, Erin J; Tung, Kenneth S; Erickson, Loren D

    2011-06-01

    Systemic lupus erythematosus and its preclinical lupus-prone mouse models are autoimmune disorders involving the production of pathogenic autoantibodies. Genetic predisposition to systemic lupus erythematosus results in B cell hyperactivity, survival of self-reactive B cells, and differentiation to autoantibody-secreting plasma cells (PCs). These corrupt B cell responses are, in part, controlled by excess levels of the cytokine BAFF that normally maintains B cell homeostasis and self-tolerance through limited production. B cell maturation Ag (BCMA) is a receptor for BAFF that, under nonautoimmune conditions, is important for sustaining enduring Ab protection by mediating survival of long-lived PCs but is not required for B cell maturation and homeostasis. Through analysis of two different lupus-prone mouse models deficient in BCMA, we identify BCMA as an important factor in regulating peripheral B cell expansion, differentiation, and survival. We demonstrate that a BCMA deficiency combined with the lpr mutation or the murine lupus susceptibility locus Nba2 causes dramatic B cell and PC lymphoproliferation, accelerated autoantibody production, and early lethality. This study unexpectedly reveals that BCMA works to control B cell homeostasis and self-tolerance in systemic autoimmunity.

  13. Pathogenic functions of B cells in autoimmune diseases: IFN-γ production joins the criminal gang.

    Science.gov (United States)

    Fillatreau, Simon

    2015-04-01

    B-cell depletion therapy has emerged as a powerful strategy to intercept the progression of T-cell-mediated autoimmune diseases such as rheumatoid arthritis, type 1 diabetes, or relapsing remitting multiple sclerosis. However, its mode of action remains incompletely defined, reflecting our incomplete understanding of the pathogenic functions of B cells in such pathologies. B cells can contribute to immune responses through the production of antibodies, presentation of antigen to T cells, and production of cytokines. In this issue of the European Journal of Immunology [Eur. J. Immunol. 2015. 45: 988-998], Olalekan et al. demonstrate that IFN-γ production by B cells is essential for the development of arthritis in mice. Lack of IFN-γ expression in B cells results in reduced autoimmune T-cell responses and autoantibody levels, impacting the arthritogenic reaction akin to that in B-cell depletion therapy. Together with other reports, the article by Olalekan et al. emphasizes the importance of cytokine-producing B cells in the pathogenesis of autoimmune diseases. In this commentary, I discuss how these findings shed new light on the roles of B cells as drivers of autoimmune pathogenesis, and how they more generally contribute to our understanding of the role of B cells in immunity.

  14. Phosphatidylserine Outer Layer Translocation Is Implicated in IL-10 Secretion by Human Regulatory B Cells.

    Science.gov (United States)

    Audo, Rachel; Hua, Charlotte; Hahne, Michael; Combe, Bernard; Morel, Jacques; Daien, Claire I

    2017-01-01

    B cells can have a regulatory role, mainly mediated by interleukin 10 (IL-10). IL-10 producing B cells (B10 cells) cells remain to be better characterized. Annexin V binds phosphatidylserine (PS), which is externalized during apoptosis. Previous works suggested that B10 cells are apoptotic cells since they bind Annexin V. Others showed that Annexin V binding could also be expressed on viable B cells. We aimed to explore if PS exposure can be a marker of B10 cells and if PS exposure has a functional role on B cell IL-10 production in healthy subjects. We found that B10 cells were significantly more often Annexin V+ than IL-10 non-producing B cells. After CpG activation, Annexin V+ B cells differentiated more often into B10 cells than Annexin Vneg B cells. Cell death and early apoptosis were similar between Annexin V+ and Annexin Vneg B cells. PS blockage, using biotinylated AnV and glyburide, decreased B10 cell differentiation. This study showed that B10 cells have an increased PS exposure independently of any apoptotic state. B cells exposing PS differentiate more into B10 cells whereas PS blockage inhibits B10 cells generation. These results strongly suggest a link between PS exposure and B10 cells.

  15. Adhesion of Human B Cells to Germinal Centers in Vitro Involves VLA-4 and INCAM-110

    Science.gov (United States)

    Freedman, Arnold S.; Munro, J. Michael; Rice, G. Edgar; Bevilacqua, Michael P.; Morimoto, Chikao; McIntyre, Bradley W.; Rhynhart, Kurt; Pober, Jordan S.; Nadler, Lee M.

    1990-08-01

    Human B lymphocytes localize and differentiate within the microenvironment of lymphoid germinal centers. A frozen section binding assay was developed for the identification of those molecules involved in the adhesive interactions between B cells and lymphoid follicles. Activated human B cells and B cell lines were found to selectively adhere to germinal centers. The VLA-4 molecule on the lymphocyte and the adhesion molecule INCAM-110, expressed on follicular dendritic cells, supported this interaction. This cellular interaction model can be used for the study of how B cells differentiate.

  16. Critical roles for Rac1 and Rac2 GTPases in B cell development and signaling.

    Science.gov (United States)

    Walmsley, Marita J; Ooi, Steen K T; Reynolds, Lucinda F; Smith, Susan Harless; Ruf, Sandra; Mathiot, Anne; Vanes, Lesley; Williams, David A; Cancro, Michael P; Tybulewicz, Victor L J

    2003-10-17

    The Rac1 guanosine triphosphatase (GTPase) has been implicated in multiple cellular functions, including actin dynamics, proliferation, apoptosis, adhesion, and migration resulting from signaling by multiple receptors, including the B cell antigen receptor (BCR). We used conditional gene targeting to generate mice with specific Rac1 deficiency in the B cell lineage. In the absence of both Rac1 and the highly related Rac2, B cell development was almost completely blocked. Both GTPases were required to transduce BCR signals leading to proliferation, survival and up-regulation of BAFF-R, a receptor for BAFF, a key survival molecule required for B cell development and maintenance.

  17. Micro RNA-19a suppresses IL-10 in peripheral B cells from patients with atherosclerosis.

    Science.gov (United States)

    Ren, Zhong-Qiao; Liu, Ning; Zhao, Kan

    2016-10-01

    The interleukin (IL)-10-production B cells play an important role in the pathogenesis of atherosclerosis (Asro) with unknown mechanism. Micro RNA (miR)-17-92 cluster has strong immune regulatory activities. This study tests a hypothesis that miR-17-92 cluster suppresses IL-10 expression in B cells of Asro patients. Patients with Asro were recruited into this study. Peripheral blood samples were collected from the patients. B cells were isolated from the blood samples and analyzed to elucidate the role of miR-17-92 in the regulation of IL-10 expression. Peripheral B cells from patients with Asro show lower levels of IL-10 than that from healthy subjects. The IL-10 expression in the B cells is negatively correlated with the expression of miR-19a in the B cells. The serum levels of tumor necrosis factor (TNF)-α, interferon (IFN)-γ and interleukin (IL)-4 in Asro patients were higher than healthy subjects. Exposure to TNF-α or IFN-γ or IL-4 suppressed IL-10 expression in B cells via increasing the expression of miR-19a in B cells, which could be abolished by Inhibition of miR-19a. TNF-α or IFN-γ or IL-4 suppresses IL-10 in B cells via up regulating miR-19a expression. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. High levels of SOX5 decrease proliferative capacity of human B cells, but permit plasmablast differentiation.

    Directory of Open Access Journals (Sweden)

    Mirzokhid Rakhmanov

    Full Text Available Currently very little is known about the differential expression and function of the transcription factor SOX5 during B cell maturation. We identified two new splice variants of SOX5 in human B cells, encoding the known L-SOX5B isoform and a new shorter isoform L-SOX5F. The SOX5 transcripts are highly expressed during late stages of B-cell differentiation, including atypical memory B cells, activated CD21low B cells and germinal center B cells of tonsils. In tonsillar sections SOX5 expression was predominantly polarized to centrocytes within the light zone. After in vitro stimulation, SOX5 expression was down-regulated during proliferation while high expression levels were permissible for plasmablast differentiation. Overexpression of L-SOX5F in human primary B lymphocytes resulted in reduced proliferation, less survival of CD138neg B cells, but comparable numbers of CD138+CD38hi plasmablasts compared to control cells. Thus, our findings describe for the first time a functional role of SOX5 during late B cell development reducing the proliferative capacity and thus potentially affecting the differentiation of B cells during the germinal center response.

  19. Increased RP105-Negative B Cells in IgG4-Related Disease.

    Science.gov (United States)

    Koarada, S; Tashiro, S; Nagao, N; Suematsu, R; Ohta, A; Tada, Y

    2013-01-01

    Four patients with IgG4-related disease (IgG4-RD) showed increased percentages of RP105-negative B cells in the peripheral blood. Case 1: A 66-year-old man having retroperitoneal fibrosis had 18.8% of RP105-negative B cells. Oral prednisolone improved the affected lesions and the percentage of RP105-negative B cells decreased (3.2%) after the treatment. Case 2: A 53-year-old man with retroperitoneal fibrosis had 27.9% of RP105-negative B cells. Case 3: A 38-year-old man with follicular hyperplasia showed increased percentage of RP105-negative B cells (8.3%). Case 4: A 60-year-old man with interstitial nephritis had 27.5% of RP105-negative B cells. The treatment decreased the numbers of RP105-negative B cells. Increased numbers of RP105-negatvie B cells is possibly associated with disease activity of IgG4-RD. Analysis of expression of RP105 on B cells may be helpful in evaluation of disease activity of IgG4-RD.

  20. Mediation of transitional B cell maturation in the absence of functional Bruton’s tyrosine kinase

    Science.gov (United States)

    Tanwar, Shalini; Dhar, Atika; Varanasi, Vineeth; Mukherjee, Tapas; Boppana, Ramanamurthy; Basak, Soumen; Bal, Vineeta; George, Anna; Rath, Satyajit

    2017-01-01

    X-linked immune-deficient (Xid) mice, carrying a mutation in Bruton’s tyrosine kinase (Btk), have multiple B cell lineage differentiation defects. We now show that, while Xid mice showed only mild reduction in the frequency of the late transitional (T2) stage of peripheral B cells, the defect became severe when the Xid genotype was combined with either a CD40-null, a TCRbeta-null or an MHC class II (MHCII)-null genotype. Purified Xid T1 and T2 B cells survived poorly in vitro compared to wild-type (WT) cells. BAFF rescued WT but not Xid T1 and T2 B cells from death in culture, while CD40 ligation equivalently rescued both. Xid transitional B cells ex vivo showed low levels of the p100 protein substrate for non-canonical NF-kappaB signalling. In vitro, CD40 ligation induced equivalent activation of the canonical but not of the non-canonical NF-kappaB pathway in Xid and WT T1 and T2 B cells. CD40 ligation efficiently rescued p100-null T1 B cells from neglect-induced death in vitro. These data indicate that CD40-mediated signals, likely from CD4 T cells, can mediate peripheral transitional B cell maturation independent of Btk and the non-canonical NF-kappaB pathway, and thus contribute to the understanding of the complexities of peripheral B cell maturation. PMID:28378771

  1. B cells produce less IL-10, IL-6 and TNF-α in myasthenia gravis.

    Science.gov (United States)

    Yilmaz, Vuslat; Oflazer, Piraye; Aysal, Fikret; Parman, Yeşim G; Direskeneli, Haner; Deymeer, Feza; Saruhan-Direskeneli, Güher

    2015-06-01

    B cells from myasthenia gravis (MG) patients with autoantibodies (Aab) against acetylcholine receptor (AChR), muscle-specific kinase (MuSK) or with no detectable Aab were investigated as cytokine producing cells in this study. B cells were evaluated for memory phenotypes and expressions of IL-10, IL-6 and IL-12A. Induced productions of IL-10, IL-6, IL-12p40, TNF-α and LT from isolated B cells in vitro were measured by immunoassays. MG patients receiving immunosuppressive treatment had higher proportions of memory B cells compared with healthy controls and untreated patients. With CD40 stimulation MG patients produced significantly lower levels of IL-10, IL-6. With CD40 and B cell receptor stimulation of B cells, TNF-α production also decreased in addition to these cytokines. The lower levels of these cytokine productions were not related to treatment. Our results confirm a disturbance of B cell subpopulations in MG subgroups on immunosuppressive treatment. B cell derived IL-10, IL-6 and TNF-α are down-regulated in MG, irrespective of different antibody productions. Ineffective cytokine production by B cells may be a susceptibility factor in dysregulation of autoimmune Aab production.

  2. Signaling and Dynamic Actin Responses of B Cells on Topographical Substrates

    Science.gov (United States)

    Ketchum, Christina; Sun, Xiaoyu; Fourkas, John; Song, Wenxia; Upadhyaya, Arpita

    B cells become activated upon physical contact with antigen on the surface of antigen presenting cells, such as dendritic cells. Binding of the B cell receptor with antigen initiates actin-mediated spreading of B cells, signaling cascades and eventually infection fighting antibodies. Lymphocytes, including B cells and T cells, have been shown to be responsive to the physical parameters of the contact surface, such as antigen mobility and substrate stiffness. However the roll of surface topography on lymphocyte function is unknown. Here we investigate the degree to which substrate topography controls actin-mediated spreading and B cell activation using nano-fabricated surfaces and live cell imaging. The model topographical system consists of 600 nanometer tall ridges with spacing varying between 800 nanometers and 5 micrometers. Using TIRF imaging we observe actin dynamics, B cell receptor motion and calcium signaling of B cells as they spread on the ridged substrates. We show that the spacing between ridges had a strong effect on the dynamics of actin and calcium influx on B cells. Our results indicate that B cells are highly sensitive to surface topography during cell spreading and signaling activation.

  3. Mediation of transitional B cell maturation in the absence of functional Bruton's tyrosine kinase.

    Science.gov (United States)

    Tanwar, Shalini; Dhar, Atika; Varanasi, Vineeth; Mukherjee, Tapas; Boppana, Ramanamurthy; Basak, Soumen; Bal, Vineeta; George, Anna; Rath, Satyajit

    2017-04-05

    X-linked immune-deficient (Xid) mice, carrying a mutation in Bruton's tyrosine kinase (Btk), have multiple B cell lineage differentiation defects. We now show that, while Xid mice showed only mild reduction in the frequency of the late transitional (T2) stage of peripheral B cells, the defect became severe when the Xid genotype was combined with either a CD40-null, a TCRbeta-null or an MHC class II (MHCII)-null genotype. Purified Xid T1 and T2 B cells survived poorly in vitro compared to wild-type (WT) cells. BAFF rescued WT but not Xid T1 and T2 B cells from death in culture, while CD40 ligation equivalently rescued both. Xid transitional B cells ex vivo showed low levels of the p100 protein substrate for non-canonical NF-kappaB signalling. In vitro, CD40 ligation induced equivalent activation of the canonical but not of the non-canonical NF-kappaB pathway in Xid and WT T1 and T2 B cells. CD40 ligation efficiently rescued p100-null T1 B cells from neglect-induced death in vitro. These data indicate that CD40-mediated signals, likely from CD4 T cells, can mediate peripheral transitional B cell maturation independent of Btk and the non-canonical NF-kappaB pathway, and thus contribute to the understanding of the complexities of peripheral B cell maturation.

  4. MicroRNA-155 influences B-cell function through PU.1 in rheumatoid arthritis.

    Science.gov (United States)

    Alivernini, Stefano; Kurowska-Stolarska, Mariola; Tolusso, Barbara; Benvenuto, Roberta; Elmesmari, Aziza; Canestri, Silvia; Petricca, Luca; Mangoni, Antonella; Fedele, Anna Laura; Di Mario, Clara; Gigante, Maria Rita; Gremese, Elisa; McInnes, Iain B; Ferraccioli, Gianfranco

    2016-09-27

    MicroRNA-155 (miR-155) is an important regulator of B cells in mice. B cells have a critical role in the pathogenesis of rheumatoid arthritis (RA). Here we show that miR-155 is highly expressed in peripheral blood B cells from RA patients compared with healthy individuals, particularly in the IgD(-)CD27(-) memory B-cell population in ACPA(+) RA. MiR-155 is highly expressed in RA B cells from patients with synovial tissue containing ectopic germinal centres compared with diffuse synovial tissue. MiR-155 expression is associated reciprocally with lower expression of PU.1 at B-cell level in the synovial compartment. Stimulation of healthy donor B cells with CD40L, anti-IgM, IL-21, CpG, IFN-α, IL-6 or BAFF induces miR-155 and decreases PU.1 expression. Finally, inhibition of endogenous miR-155 in B cells of RA patients restores PU.1 and reduces production of antibodies. Our data suggest that miR-155 is an important regulator of B-cell activation in RA.

  5. B cells promote tumor progression via STAT3 regulated-angiogenesis.

    Directory of Open Access Journals (Sweden)

    Chunmei Yang

    Full Text Available The role of B cells in cancer and the underlying mechanisms remain to be further explored. Here, we show that tumor-associated B cells with activated STAT3 contribute to tumor development by promoting tumor angiogenesis. B cells with or without Stat3 have opposite effects on tumor growth and tumor angiogenesis in both B16 melanoma and Lewis Lung Cancer mouse models. Ex vivo angiogenesis assays show that B cell-mediated tumor angiogenesis is mainly dependent on the induction of pro-angiogenic gene expression, which requires Stat3 signaling in B cells. Furthermore, B cells with activated STAT3 are mainly found in or near tumor vasculature and correlate significantly with overall STAT3 activity in human tumors. Moreover, the density of B cells in human tumor tissues correlates significantly with expression levels of several STAT3-downstream pro-angiogenic genes, as well as the degree of tumor angiogenesis. Together, these findings define a novel role of B cells in promoting tumor progression through angiogenesis and identify STAT3 in B cells as potential therapeutic target for anti-angiogenesis therapy.

  6. Scarcity of autoreactive human blood IgA(+) memory B cells.

    Science.gov (United States)

    Prigent, Julie; Lorin, Valérie; Kök, Ayrin; Hieu, Thierry; Bourgeau, Salomé; Mouquet, Hugo

    2016-10-01

    Class-switched memory B cells are key components of the "reactive" humoral immunity, which ensures a fast and massive secretion of high-affinity antigen-specific antibodies upon antigenic challenge. In humans, IgA class-switched (IgA(+) ) memory B cells and IgA antibodies are abundant in the blood. Although circulating IgA(+) memory B cells and their corresponding secreted immunoglobulins likely possess major protective and/or regulatory immune roles, little is known about their specificity and function. Here, we show that IgA(+) and IgG(+) memory B-cell antibodies cloned from the same healthy humans share common immunoglobulin gene features. IgA and IgG memory antibodies have comparable lack of reactivity to vaccines, common mucosa-tropic viruses and commensal bacteria. However, the IgA(+) memory B-cell compartment contains fewer polyreactive clones and importantly, only rare self-reactive clones compared to IgG(+) memory B cells. Self-reactivity of IgAs is acquired following B-cell affinity maturation but not antibody class switching. Together, our data suggest the existence of different regulatory mechanisms for removing autoreactive clones from the IgG(+) and IgA(+) memory B-cell repertoires, and/or different maturation pathways potentially reflecting the distinct nature and localization of the cognate antigens recognized by individual B-cell populations.

  7. The human fetal lymphocyte lineage: identification by CD27 and LIN28B expression in B cell progenitors

    Science.gov (United States)

    McWilliams, Laurie; Su, Kuei-Ying; Liang, Xiaoe; Liao, Dongmei; Floyd, Serina; Amos, Joshua; Moody, M. Anthony; Kelsoe, Garnett; Kuraoka, Masayuki

    2013-01-01

    CD27, a member of the TNFR superfamily, is used to identify human memory B cells. Nonetheless, CD27+ B cells are present in patients with HIGM1 syndrome who are unable to generate GCs or memory B cells. CD27+IgD+ fetal B cells are present in umbilical cord blood, and CD27 may also be a marker of the human B1-like B cells. To define the origin of naïve CD27+IgD+ human B cells, we studied B cell development in both fetal and adult tissues. In human FL, most CD19+ cells coexpressed CD10, a marker of human developing B cells. Some CD19+CD10+ B cells expressed CD27, and these fetal CD27+ cells were present in the pro-B, pre-B, and immature/transitional B cell compartments. Lower frequencies of phenotypically identical cells were also identified in adult BM. CD27+ pro-B, pre-B, and immature/transitional B cells expressed recombination activating gene-1, terminal deoxynucleotidyl transferase and Vpre-B mRNA comparably to their CD27− counterparts. CD27+ and CD27− developing B cells showed similar Ig heavy chain gene usage with low levels of mutations, suggesting that CD27+ developing B cells are distinct from mutated memory B cells. Despite these similarities, CD27+ developing B cells differed from CD27− developing B cells by their increased expression of LIN28B, a transcription factor associated with the fetal lymphoid lineages of mice. Furthermore, CD27+ pro-B cells efficiently generated IgM+IgD+ immature/transitional B cells in vitro. Our observations suggest that CD27 expression during B cell development identifies a physiologic state or lineage for human B cell development distinct from the memory B cell compartment. PMID:23901121

  8. Engagement of CD22 on B cells with the monoclonal antibody epratuzumab stimulates the phosphorylation of upstream inhibitory signals of the B cell receptor.

    Science.gov (United States)

    Lumb, Simon; Fleischer, Sarah J; Wiedemann, Annika; Daridon, Capucine; Maloney, Alison; Shock, Anthony; Dörner, Thomas

    2016-06-01

    The binding of antigen to the B cell receptor (BCR) results in a cascade of signalling events that ultimately drive B cell activation. Uncontrolled B cell activation is regulated by negative feedback loops that involve inhibitory co-receptors such as CD22 and CD32B that exert their functions following phosphorylation of immunoreceptor tyrosine-based inhibition motifs (ITIMs). The CD22-targeted antibody epratuzumab has previously been shown to inhibit BCR-driven signalling events, but its effects on ITIM phosphorylation of CD22 and CD32B have not been properly evaluated. The present study therefore employed both immunoprecipitation and flow cytometry approaches to elucidate the effects of epratuzumab on direct phosphorylation of key tyrosine (Tyr) residues on both these proteins, using both transformed B cell lines and primary human B cells. Epratuzumab induced the phosphorylation of Tyr(822) on CD22 and enhanced its co-localisation with SHP-1. Additionally, in spite of high basal phosphorylation of other key ITIMs on CD22, in primary human B cells epratuzumab also enhanced phosphorylation of Tyr(807), a residue involved in the recruitment of Grb2. Such initiation events could explain the effects of epratuzumab on downstream signalling in B cells. Finally, we were able to demonstrate that epratuzumab stimulated the phosphorylation of Tyr(292) on the low affinity inhibitory Fc receptor CD32B which would further attenuate BCR-induced signalling. Together, these data demonstrate that engagement of CD22 with epratuzumab leads to the direct phosphorylation of key upstream inhibitory receptors of BCR signalling and may help to explain how this antibody modulates B cell function.

  9. Unusual patterns of immunoglobulin gene rearrangement and expression during human B cell ontogeny: human B cells can simultaneously express cell surface kappa and lambda light chains

    OpenAIRE

    1993-01-01

    Immunoglobulin gene rearrangement during mammalian B cell development generally follows an ordered progression, beginning with heavy (H) chain genes and proceeding through kappa and lambda light (L) chain genes. To determine whether the predicted kappa-->lambda hierarchy was occurring in vitro, we generated Epstein-Barr virus-transformed cell lines from cultures undergoing human pre-B cell differentiation. A total of 143 cell lines were established. 24 expressed cell surface mu/lambda by flow...

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

    Science.gov (United States)

    2016-09-01

    University of Pennsylvania, Philadelphia, PA 19104; ‡School of Veterinary Medicine , University of Pennsylvania, Philadelphia, PA 19104; xDepart- ment of...that Tbet+ B cells are a memory B cell subset generated by BCR-delivered TLR9 or TLR7 agonists in the context of an inflammatory cytokine milieu...via the BCR. Pathogen degradation leads to viral nucleic acids engaging TLR7 or TLR9. Processing and loading of viral peptides onto MHCII molecules

  11. Variant B Cell Receptor Isotype Functions Differ in Hairy Cell Leukemia with Mutated BRAF and IGHV Genes

    NARCIS (Netherlands)

    Weston-Bell, Nicola J.; Forconi, Francesco; Kluin-Nelemans, Hanneke C.; Sahota, Surinder S.

    2014-01-01

    A functional B-cell receptor (BCR) is critical for survival of normal B-cells, but whether it plays a comparable role in B-cell malignancy is as yet not fully delineated. Typical Hairy Cell Leukemia (HCL) is a rare B-cell tumor, and unique in expressing multiple surface immunoglobulin (sIg) isotypes

  12. Activation of resting human B cells by helper T-cell clone supernatant: characterization of a human B-cell-activating factor.

    Science.gov (United States)

    Diu, A; Gougeon, M L; Moreau, J L; Reinherz, E L; Thèze, J

    1987-12-01

    The effects of helper T-cell clone supernatants on resting human B cells were investigated. Four different helper T-cell clones (two T4+ and two T8+) were stimulated by anti-T3 monoclonal antibodies on Sepharose beads or anti-T11(2) plus anti-T11(3) monoclonal antibodies. The supernatants from these activated clones induced the proliferation of highly purified resting B lymphocytes from the peripheral blood. The B cells exhibited a cell size and a surface-antigen pattern (4F2 antigen and transferrin receptor) of phase G0 B cells, and they were functionally resting. In response to T-cell supernatants a large fraction of the B cells enlarged and expressed 4F2 antigens and transferrin receptors. In gel filtration, the corresponding activity migrated with an apparent Mr of 12,000-15,000. Our findings strongly support the existence of a human B-cell-activating factor acting on resting B cells and causing them to enter phase G1 of the cell cycle.

  13. Early B-cell factor 1 (EBF1) is critical for transcriptional control of SLAMF1 gene in human B cells.

    Science.gov (United States)

    Schwartz, Anton M; Putlyaeva, Lidia V; Covich, Milica; Klepikova, Anna V; Akulich, Kseniya A; Vorontsov, Ilya E; Korneev, Kirill V; Dmitriev, Sergey E; Polanovsky, Oleg L; Sidorenko, Svetlana P; Kulakovskiy, Ivan V; Kuprash, Dmitry V

    2016-10-01

    Signaling lymphocytic activation molecule family member 1 (SLAMF1)/CD150 is a co-stimulatory receptor expressed on a variety of hematopoietic cells, in particular on mature lymphocytes activated by specific antigen, costimulation and cytokines. Changes in CD150 expression level have been reported in association with autoimmunity and with B-cell chronic lymphocytic leukemia. We characterized the core promoter for SLAMF1 gene in human B-cell lines and explored binding sites for a number of transcription factors involved in B cell differentiation and activation. Mutations of SP1, STAT6, IRF4, NF-kB, ELF1, TCF3, and SPI1/PU.1 sites resulted in significantly decreased promoter activity of varying magnitude, depending on the cell line tested. The most profound effect on the promoter strength was observed upon mutation of the binding site for Early B-cell factor 1 (EBF1). This mutation produced a 10-20 fold drop in promoter activity and pinpointed EBF1 as the master regulator of human SLAMF1 gene in B cells. We also identified three potent transcriptional enhancers in human SLAMF1 locus, each containing functional EBF1 binding sites. Thus, EBF1 interacts with specific binding sites located both in the promoter and in the enhancer regions of the SLAMF1 gene and is critical for its expression in human B cells.

  14. CD80 expression on B cells regulates murine T follicular helper development, germinal center B cell survival, and plasma cell generation.

    Science.gov (United States)

    Good-Jacobson, Kim L; Song, Eunice; Anderson, Shannon; Sharpe, Arlene H; Shlomchik, Mark J

    2012-05-01

    Germinal center (GC) B cells and T follicular helper (T(FH)) cells interact in the production of high-affinity long-lived plasma cells (PCs) and memory B cells, although the mechanisms regulating the formation of these long-lived populations remain unclear. Because CD80 is one of the few markers shared by human and murine memory B cells, we investigated its role in the development of GCs, memory cells, and PCs. In CD80-deficient mice, fewer long-lived PCs were generated upon immunization compared with that in B6 controls. In concert, the absence of CD80 resulted in an increase in apoptotic GC B cells during the contraction phase of the GC. CD80(-/-) mice had fewer T(FH) cells compared with that of B6, and residual T(FH) cells failed to mature, with decreased ICOS and PD-1 expression and decreased synthesis of IL-21 mRNA. Mixed bone marrow chimeras demonstrated a B cell-intrinsic requirement for CD80 expression for normal T(FH) cell and PC development. Therefore, B cell expression of CD80 plays a critical role in regulating B-T interactions in both early and late GC responses. This, in turn, results in impaired ability to produce long-lived PCs. These data provide new insights into the development of GCs and Ab-forming cells and the functions of CD80 in humoral immunity.

  15. The activation of B cells enhances DC-SIGN expression and promotes susceptibility of B cells to HPAI H5N1 infection.

    Science.gov (United States)

    Na-Ek, Prasit; Thewsoongnoen, Jutarat; Thanunchai, Maytawan; Wiboon-Ut, Suwimon; Sa-Ard-Iam, Noppadol; Mahanonda, Rangsini; Thitithanyanont, Arunee

    2017-09-02

    The interplay between highly pathogenic avian influenza (HPAI) H5N1 virus and immune cells has been extensively studied for years, as host immune components are thought to play significant roles in promoting the systemic spread of the virus and responsible for cytokine storm. Previous studies suggested that the interaction of B cells and monocytes could promote HPAI H5N1 infection by enhancing avian influenza virus receptor expression. In this study, we further investigate the relationship between the HPAI H5N1 virus, activated B cells, and DC-SIGN expression. DC-SIGN has been described as an important factor for mediating various types of viral infection. Here, we first demonstrate that HPAI H5N1 infection could induce an activation of B cells, which was associated with DC-SIGN expression. Using CD40L and recombinant IL-4 for B cell stimulation, we determined that DC-SIGN expressed on activated B cells was able to enhance its susceptibility to HPAI H5N1 infection. Our findings uncover the interplay between this H5N1 virus and B cells and provide important information in understanding how the virus overcomes our immune system, contributing to its unusual immunopathogenesis. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. The spectrum of B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and classical Hodgkin lymphoma: a description of 10 cases.

    Science.gov (United States)

    Gualco, Gabriela; Natkunam, Yasodha; Bacchi, Carlos E

    2012-05-01

    B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and classical Hodgkin lymphoma, is a diagnostic provisional category in the World Health Organization (WHO) 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. Typically, these cases share features intermediate between diffuse large B-cell lymphoma and classical Hodgkin lymphoma, or include characteristics of both lymphomas. The rarity of such cases poses a tremendous challenge to both pathologists and oncologists because its differential diagnosis has direct implications for management strategies. In this study, we present 10 cases of B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and classical Hodgkin lymphoma and have organized the criteria described by the WHO into four patterns along with detailed clinical, morphological and immunophenotypic characterization and outcome data. Our findings show a male preponderance, median age of 37 years and a mediastinal presentation in 80% of cases. All cases expressed at least two markers associated with B-cell lineage and good response to combination chemotherapy currently employed for non-Hodgkin lymphomas.

  17. Idiotype vaccines for human B-cell malignancies.

    Science.gov (United States)

    Inoges, S; de Cerio, A Lopez-Diaz; Soria, E; Villanueva, H; Pastor, F; Bendandi, M

    2010-01-01

    After twenty years of use in humans, customized idiotypic vaccination yet remains a non-approved, experimental therapeutic option for patients with lymphoma and myeloma. Potentially applicable to all B-cell malignancies whose cells express a clonal immunoglobulin or its epitopes on their surface, this treatment is designed to prevent disease recurrence or progression. Mostly used in follicular lymphoma patients so far, idiotype vaccines have clearly shown biological efficacy, clinical efficacy and clinical benefit in this setting, although no study aiming at regulatory approval of the procedure has been able to meet its main clinical endpoints. In mantle cell lymphoma, only biological efficacy has been proven for idiotypic vaccination, while in multiple myeloma a limited number of studies support the notion of biological and perhaps even clinical efficacy, although no credible evidence of clinical benefit has still emerged. Idiotype vaccines have been produced and administered in a number of substantially different manners. Therefore, the results of most clinical trials cannot be easily compared, and even less pooled together in meaningful meta-analyses. A more creative and yet scientifically sound way to design clinical trials of customized active immunotherapies will be key to the future development of idiotype vaccines, particularly considering that we currently lack any clinical or biological indicator to possibly predict which patients are more likely to respond to idiotypic vaccination from an immunologic point of view. This review aims at summarizing the multifaceted success achieved by idiotype vaccines, as well as at outlining the challenges awaiting them in the near future: how to improve feasibility, immunogenicity and efficacy, as well as how to confirm benefit and gain regulatory approval.

  18. Clinicopathological features of aggressive B-cell lymphomas including B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell and Burkitt lymphomas: a study of 44 patients from Argentina.

    Science.gov (United States)

    Bürgesser, María Virginia; Gualco, Gabriela; Diller, Ana; Natkunam, Yasodha; Bacchi, Carlos E

    2013-06-01

    Aggressive B-cell lymphomas incorporate a wide spectrum of lymphomas that pose challenges in diagnosis as well as treatment. We evaluated the clinicopathological features of 44 patients with aggressive B-cell lymphomas which were classified into 3 groups based on the World Health Organization 2008 classification as follows: including 30 cases of diffuse large B-cell lymphoma (DLBCL), 8 cases of Burkitt lymphoma (BL) and 6 cases of B-cell lymphoma, unclassifiable, with features intermediate between Burkitt lymphoma and diffuse large B-cell lymphoma (BCLU). Male predominance was observed in BL and BCLU groups and the mean age varied from 29 years in BL, 61 years in DLBCL and 70 years in BCLU. Patients with BCLU presented at more advanced stages and had a higher international prognostic index. By immunohistochemistry, they shared characteristics of both BL (including more frequent expression of SOX11) and DLBCL. FISH analyses showed three cases with more than one rearrangement: one MYC/BCL2 and two BCL2/BCL6, in addition to which one case with BCL2/IGH translocation and another with MYC rearrangement were also detected. The mean follow-up survival time of BCLU was 6.6 months, which was significantly shorter in comparison to DLBCL (31 months) and BL (30 months), respectively. The importance of recognizing this BCLU group relies on its different clinical course, poor prognosis and shorter survival than DLBCL and BL. An accurate diagnosis is critical for risk stratification and to improve therapeutic approaches and outcomes.

  19. In vivo, multimodal imaging of B cell distribution and response to antibody immunotherapy in mice.

    Directory of Open Access Journals (Sweden)

    Daniel L J Thorek

    Full Text Available BACKGROUND: B cell depletion immunotherapy has been successfully employed to treat non-Hodgkin's lymphoma. In recent years, increasing attention has been directed towards also using B-cell depletion therapy as a treatment option in autoimmune disorders. However, it appears that the further development of these approaches will depend on a methodology to determine the relation of B-cell depletion to clinical response and how individual patients should be dosed. Thus far, patients have generally been followed by quantification of peripheral blood B cells, but it is not apparent that this measurement accurately reflects systemic B cell dynamics. METHODOLOGY/PRINCIPAL FINDINGS: Cellular imaging of the targeted population in vivo may provide significant insight towards effective therapy and a greater understanding of underlying disease mechanics. Superparamagnetic iron oxide (SPIO nanoparticles in concert with near infrared (NIR fluorescent dyes were used to label and track primary C57BL/6 B cells. Following antibody mediated B cell depletion (anti-CD79, NIR-only labeled cells were expeditiously cleared from the circulation and spleen. Interestingly, B cells labeled with both SPIO and NIR were not depleted in the spleen. CONCLUSIONS/SIGNIFICANCE: Whole body fluorescent tracking of B cells enabled noninvasive, longitudinal imaging of both the distribution and subsequent depletion of B lymphocytes in the spleen. Quantification of depletion revealed a greater than 40% decrease in splenic fluorescent signal-to-background ratio in antibody treated versus control mice. These data suggest that in vivo imaging can be used to follow B cell dynamics, but that the labeling method will need to be carefully chosen. SPIO labeling for tracking purposes, generally thought to be benign, appears to interfere with B cell functions and requires further examination.

  20. IL-15 Expression on RA Synovial Fibroblasts Promotes B Cell Survival

    Science.gov (United States)

    Benito-Miguel, Marta; García-Carmon