Expression of Toll-like receptors （TLRs） in B cells provides a cell-intrinsic mechanism for innate signals regulating adaptive immune responses. In combination with other signaling pathways in B cells, including thr...Expression of Toll-like receptors （TLRs） in B cells provides a cell-intrinsic mechanism for innate signals regulating adaptive immune responses. In combination with other signaling pathways in B cells, including through the B-cell receptor （BCR）, TLR signaling plays multiple roles in B-cell differentiation and activation. The outcome of TLR signaling in B cells is largely context-dependent, which partly explains discrepancies among in vitroand in vivostudies, or studies using different immunogens. We focus on recent findings on how B-cell-intrinsic TLR signaling regulates antibody responses, including germinal center formation and autoantibody production in autoimmune disease models. In addition, TLR signaling also acts on the precursors of B cells, which could influence the immune response of animals by shaping the composition of the immune system. With TLR signaling modulating immune responses at these different levels, much more needs to be understood before we can depict the complete functions of innate signaling in host defense.展开更多
Rabies remains a public health threat that kills approximately 59,000 people worldwide each year,most of which are from the developing countries of Africa and Asia where dog rabies are endemic.Therefore, developing an...Rabies remains a public health threat that kills approximately 59,000 people worldwide each year,most of which are from the developing countries of Africa and Asia where dog rabies are endemic.Therefore, developing an affordable and efficacious vaccine is crucial for rabies control in these countries. Interleukin(IL)-15, an immunoregulatory cytokine, is a pluripotent molecule with therapeutic potential, which targets many cell types and links the innate and adaptive immune system. In this study, IL-15 gene was cloned and inserted into the genome of a recombinant rabies virus(RABV) strain LBNSE(designated as LBNSE-IL15), and the effect of over-expression of IL-15 on the immunogenicity of RABV was investigated. It was found that mice vaccinated with LBNSEIL15 could induce significantly higher level of virus-neutralizing antibody(VNA) than those immunized with LBNSE, resulting in the higher protection after challenge. Further investigation was performed to find out the possible role of IL-15 plays in the process of antibody induction, and it was found that LBNSE-IL15 could enhance the maturation of dendritic cells(DCs) in immunized mice. Furthermore, the mice immunized with LBNSE-IL15 could promote the T_(FH) cells differentiation and the generation of germinal center B cells and plasma cells. Together, these data indicated that IL-15 could be a potential adjuvant in enhancing the immunogenicity of RABV, contributing to the development of more-efficacious rabies vaccines.展开更多
Myasthenia gravis(MG) is a prototypical antibody-mediated neurological autoimmune disease with the involvement of humoral immune responses in its pathogenesis. T follicular helper(Tfh) cells have been implicated in ma...Myasthenia gravis(MG) is a prototypical antibody-mediated neurological autoimmune disease with the involvement of humoral immune responses in its pathogenesis. T follicular helper(Tfh) cells have been implicated in many autoimmune diseases. However, whether and how Tfh cells are involved in MG remain unclear.Here, we established and studied a widely-used and approved animal model of human MG, the rat model with acetylcholine receptor alpha(AChRa) subunit(RAChR97–116)-induced experimental autoimmune myasthenia gravis(EAMG). This model presented mild bodyweight loss 10 days after the first immunization(representing the early stage of disease) and more obvious clinical manifestations and body-weight loss 7 days after the second immunization(representing the late stage of disease). AChR-specific pre-Tfh cells and mature Tfh cells were detected in these two stages, respectively. In cocultures of Tfh cells and B cells, the number of IgG2 bsecreting B cells and the level of anti-AChR antibodies in the supernatant were higher in the cultures containing EAMG-derived Tfh cells. In immunohistochemistry and immunofluorescence assays, a substantial number of CD4^+/Bcl-6^+ T cells and a greater number of larger germinal centers were observed in lymph node tissues resected from EAMG rats. Based on these results, wehypothesize that an AChR-specific Tfh cell-mediated humoral immune response contributes to the development of EAMG.展开更多
基金This work was supported by research grants from the National Natural Science Foundation of China to BH （31170848） and to ZH （31200669）.
文摘Expression of Toll-like receptors （TLRs） in B cells provides a cell-intrinsic mechanism for innate signals regulating adaptive immune responses. In combination with other signaling pathways in B cells, including through the B-cell receptor （BCR）, TLR signaling plays multiple roles in B-cell differentiation and activation. The outcome of TLR signaling in B cells is largely context-dependent, which partly explains discrepancies among in vitroand in vivostudies, or studies using different immunogens. We focus on recent findings on how B-cell-intrinsic TLR signaling regulates antibody responses, including germinal center formation and autoantibody production in autoimmune disease models. In addition, TLR signaling also acts on the precursors of B cells, which could influence the immune response of animals by shaping the composition of the immune system. With TLR signaling modulating immune responses at these different levels, much more needs to be understood before we can depict the complete functions of innate signaling in host defense.
基金partially supported by the National Natural Science Foundation of China(31402176,31372419,31522057)the National Program on Key Research Project of China(2016YFD0500400)+2 种基金the Fundamental Research Funds for the Central Universities(2662016 QD036,to MZ)the Ministry of Science and Technology of China(863 program,number 2011AA10A212)the Ministry of Agriculture of China(special fund for Agro-scientific research in the Public Interest,2013 03042,to ZFF)
文摘Rabies remains a public health threat that kills approximately 59,000 people worldwide each year,most of which are from the developing countries of Africa and Asia where dog rabies are endemic.Therefore, developing an affordable and efficacious vaccine is crucial for rabies control in these countries. Interleukin(IL)-15, an immunoregulatory cytokine, is a pluripotent molecule with therapeutic potential, which targets many cell types and links the innate and adaptive immune system. In this study, IL-15 gene was cloned and inserted into the genome of a recombinant rabies virus(RABV) strain LBNSE(designated as LBNSE-IL15), and the effect of over-expression of IL-15 on the immunogenicity of RABV was investigated. It was found that mice vaccinated with LBNSEIL15 could induce significantly higher level of virus-neutralizing antibody(VNA) than those immunized with LBNSE, resulting in the higher protection after challenge. Further investigation was performed to find out the possible role of IL-15 plays in the process of antibody induction, and it was found that LBNSE-IL15 could enhance the maturation of dendritic cells(DCs) in immunized mice. Furthermore, the mice immunized with LBNSE-IL15 could promote the T_(FH) cells differentiation and the generation of germinal center B cells and plasma cells. Together, these data indicated that IL-15 could be a potential adjuvant in enhancing the immunogenicity of RABV, contributing to the development of more-efficacious rabies vaccines.
基金supported by the National Natural Science Foundation of China(81000536,81471227,31371079,31671112 and 81430035)the China Postdoctoral Science Foundation(20100471094)+3 种基金the Returned Overseas Scholars Foundation of the Natural Science Foundation of Heilongjiang Province,China(LC2015029,QC2015022)the Science and Technology Research Project of the Education Department of Heilongjiang Province,China(12541z008)the Heilongjiang Province Postdoctoral Science Foundation(LBH-Q131111)the Open Topic of Key Laboratory of Neurobiology,General Colleges and Universities in Heilongjiang Province,China(2013HLJKLNT-05)
文摘Myasthenia gravis(MG) is a prototypical antibody-mediated neurological autoimmune disease with the involvement of humoral immune responses in its pathogenesis. T follicular helper(Tfh) cells have been implicated in many autoimmune diseases. However, whether and how Tfh cells are involved in MG remain unclear.Here, we established and studied a widely-used and approved animal model of human MG, the rat model with acetylcholine receptor alpha(AChRa) subunit(RAChR97–116)-induced experimental autoimmune myasthenia gravis(EAMG). This model presented mild bodyweight loss 10 days after the first immunization(representing the early stage of disease) and more obvious clinical manifestations and body-weight loss 7 days after the second immunization(representing the late stage of disease). AChR-specific pre-Tfh cells and mature Tfh cells were detected in these two stages, respectively. In cocultures of Tfh cells and B cells, the number of IgG2 bsecreting B cells and the level of anti-AChR antibodies in the supernatant were higher in the cultures containing EAMG-derived Tfh cells. In immunohistochemistry and immunofluorescence assays, a substantial number of CD4^+/Bcl-6^+ T cells and a greater number of larger germinal centers were observed in lymph node tissues resected from EAMG rats. Based on these results, wehypothesize that an AChR-specific Tfh cell-mediated humoral immune response contributes to the development of EAMG.
