Role of TCRy& T cells in the mucosal response to intestinal infection

描述（由申请人提供）：尽管临床相关的感染因子如人类免疫缺陷病毒通过肠道粘膜进入，但肠道T细胞对感染的反应仍未得到充分研究。单核增生李斯特菌（Listeria monocytogenes， LM）已被用作研究T细胞反应的模式生物，LM的正常感染途径和作为疫苗使用的潜在途径是通过摄入。然而，绝大多数LM免疫学研究使用接种途径而不是口服。此外，在所使用的菌株中，内毒素A蛋白与人e -钙粘蛋白具有高亲和力，但与小鼠e -钙粘蛋白结合较差。这种受体-配体配对是LM进入肠上皮细胞所必需的。本文提出的口腔感染研究利用重组LM表达一种与小鼠e -钙粘蛋白高亲和力的内毒素a蛋白。因此，我们的研究概述了LM的生理途径和切入点。我们的初步研究揭示了粘膜TCRgd T细胞对口腔LM感染的显著反应，其动力学模拟适应性T细胞反应。最重要的是，粘膜TCRgd T细胞的这种表型和功能上不同的亚群被长期保留，并在受到挑战时经历回忆反应。在本提案中需要验证的假设是，这种假定的记忆TCRgd T细胞的特殊子集对于防止LM感染很重要，并且还调节CDB的长期保护性TCRa反应。这一假设将在以下具体目标中进行检验：目标1。测试TCRgd的一个亚群是否代表真正的粘膜记忆细胞。将对口腔LM感染的原发性和继发性TCRgd细胞反应进行详细的动力学、表型和功能分析。目标2。确定LM感染对粘膜TCRgd激活的要求。在这里，我们将测试树突状细胞，共刺激和细胞因子在增加原发性和继发性TCRgd细胞反应中的作用。目标3。观察粘膜TCRgd细胞对口腔LM感染的反应。口腔感染系统提供了一个特殊的机会来检查粘膜TCRgd细胞反应的解剖。

DESCRIPTION (provided by applicant): Despite the fact that clinically relevant infectious agents such as human immunodeficiency virus enter through the intestinal mucosa, the intestinal T cell response to infection remains understudied. Listeria monocytogenes (LM) has been used as a model organism for studying T cell responses and the normal route of infection for LM and a potential route for use of LM as a vaccine is through ingestion. Nevertheless, the vast majority of LM immunological studies utilize inoculation routes other than oral. Moreover in the bacterial strains used, the internalin A protein binds human E-cadherin with high affinity but poorly binds mouse E-cadherin. This receptor-ligand pairing is required for entry of LM into intestinal epithelial cells. The oral infection studies proposed here utilize a recombinant LM that expresses an internalin A protein with high affinity for mouse E-cadherin. Thus, the physiologic route and entry point of LM is recapitulated in our studies. Our preliminary studies revealed a remarkable mucosal TCRgd T cell response to oral LM infection, whose kinetics mimic an adaptive T cell response. Most importantly, this phenotypically and functionally distinct subset of mucosal TCRgd T cells are retained long-term and undergo a recall response upon challenge. The hypothesis to be tested in this proposal is that this specialized subset of putative memory TCRgd T cells is important for protection against LM infection and also regulates the long-term protective CDB TCRa¿ response. This hypothesis will be tested in the following specific aims: Aim 1. To test whether a subset of TCRgd represent bona fide mucosal memory cells. A detailed kinetic, phenotypic and functional analysis of the primary and secondary TCRgd cell response to oral LM infection will be undertaken. Aim 2. To determine the requirements for mucosal TCRgd activation in response to LM infection. Here we will test the role of dendritic cells, costimulation and cytokines in mounting primary and secondary TCRgd cell responses. Aim 3. To visualize the mucosal TCRgd cell response to oral LM infection. The oral infection system provides an exceptional opportunity to examine the anatomy of the mucosal TCRgd cell response.