Origins of serum IgA antibodies

描述（由申请人提供）：我们的目的是确定控制持久IgA反应产生的因素，并确定共生微生物在促进对肠道抗原和病原体的全身IgA反应中的作用。支持这项工作的中心假设是，分节丝状细菌（SFB）通过启动肠道常驻T细胞和B细胞来促进全身IgA反应，从而增加粘膜IgA+分泌细胞的产生，这些细胞随后在骨髓中为长寿的浆细胞定殖。进一步的实验将确定肠道和骨髓中分泌iga的浆细胞在稳定状态下和对肠道病原体作出反应时的寿命。具体来说，我们将：1)确定SFB定殖对骨髓浆细胞池的影响，2)确定SFB定殖对肠道微生物的全身IgA反应的影响，3)确定LP和BM中IgA+ pc的衰变动力学。

DESCRIPTION (provided by applicant): Our intent is to define the factors controlling the generation of lasting IgA responses and determine the role of commensal microbes in promoting systemic IgA responses to enteric antigens and pathogens. The central hypothesis underpinning this work is that Segmented Filamentous Bacteria (SFB) promote systemic IgA responses by priming gut-resident T and B cells, thus augmenting the generation of mucosal IgA+-secreting cells that subsequently colonize niches for long-lived plasma cells in the bone marrow. Additional experiments will define the life span of IgA-secreting plasma cells in the gut and the bone marrow, at steady state and in response to an enteric pathogen. Specifically we will: 1) Define the impact of SFB colonization on the bone marrow plasma cell pool, 2) Define the impact of SFB colonization on systemic IgA responses to enteric microbes, 3) Define decay kinetics for IgA+ PCs in the LP and the BM.