Priming of Antifungal T-Cells at Mucosal and Systemic Sites

粘膜和全身部位抗真菌 T 细胞的启动

• 批准号: 7540447
• 负责人: Marcel Wuethrich
• 金额: $ 22.05万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-12-15 至 2009-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7540447
• 关键词: Activation Analysis; Adoptive Transfer; Antifungal Agents; Antigens; Attenuated; Attenuated Live Virus Vaccine; Autologous; Blastomyces; Blastomyces dermatitidis; CD4 Positive T Lymphocytes; Cells; Communicable Diseases; Complex; Data; Development; Disease; Effector Cell; Engineering; Event; Evolution; Experimental Models; Generations; Genital system; Hand; Immune; Immune response; Immunity; Immunization; Immunology; Infection; Infection Control; Infectious Agent; Influenza; Knowledge; Lead; Lung; Lung diseases; Mediating; Microbe; Molecular; Monitor; Mucosal Immunity; Mucous Membrane; Mus; National Institute of Allergy and Infectious Disease; Papillomavirus; Patients; Phase; Poliomyelitis; Property; Reagent; Research; Resistance; Respiratory Mucosa; Respiratory Tract Infections; Rotavirus; Route; Site; Skin; Staging; Surface; System; T-Cell Receptor; T-Lymphocyte; Testing; Tissues; Transgenic Mice; Transgenic Organisms; United States National Institutes of Health; Vaccination; Vaccines; Work; base; design; fungus; improved; in vivo; insight; lymph nodes; microbial; mucosal vaccination; mucosal vaccine; pathogen; prevent; respiratory; response; subcutaneous; tool

DESCRIPTION (provided by applicant): Fungal pathogens and most infectious agents enter the body at mucosal surfaces. Mucosal immune priming induces both systemic and mucosal resistance, and is believed to be the ideal strategy to prevent or treat infections that arise from a mucosal surface. Systemic priming, in turn, usually induces poor mucosal immunity and is judged to be less desirable against mucosal infections. Contrary to this paradigm, we find that a live-attenuated, vaccine strain of Blastomyces dermatitidis can protect mice against a lethal pulmonary infection (via Th1 CD4+ T cells) when the attenuated strain is delivered only by the subcutaneous route, and not by the respiratory route. Here, we will investigate the fundamental mechanisms by which these 2 routes of antigen (Ag) delivery trigger CD4+ T cells during the priming and the recall phases. We will endeavor to uncover the cellular and molecular mechanisms that lead to effective or failed priming of T cells in the skin versus the lung. T cell receptor (TCR) transgenic (Tg) systems are arguably the best immunological tools to decipher the activation of clonal T cells in vivo, but there are no such reagents available for studying T-cell immunity to the dimorphic fungi. Therefore, we propose to create a Blastomyces-specific CD4+ TCR Tg mouse to monitor and analyze the activation of Ag-specific CD4+ T cells in these two immunologically disparate settings. We hypothesize that the subcutaneous delivery of Ag will prime TCR Tg, Blastomcyes-specific CD4+ T-cells in the skin-draining lymph nodes to become activated Th1 effector cells, and protect against lung challenge upon recall. Mucosal priming, on the other hand, will lead to the generation of functionally impaired Th1 effectors unable to provide resistance to challenge. Our specific aims are to: 1) Develop an adoptive transfer system to monitor Blastomyces-specific CD4+ T cells in vivo. Fungal-specific TCR Tg mice will be created from a T cell clone that protects mice against experimental infection. TCR Tg cells will be used to establish an autologous adoptive transfer system to track the phenotypic and functional properties of protective Ag-specific T cells during the priming phase in the skin, and on recall in the lung. 2) Identify whether and how mucosal priming fails to engender Ag-specific Th1 CD4+ cells. TCR Tg cells will let us track the critical stages of the CD4+ T cell response after Ag exposure at the respiratory mucosa: recruitment, activation, proliferation and differentiation in the lung and draining lymph nodes during the priming and recall phases. These events will be compared/contrasted to those after Ag exposure in the skin. Our studies will yield new insight into the evolution of T cell responses and immunity in mucosal tissues. This knowledge will contribute to the development of effective strategies to induce acquired, protective immunity for improved control of fungal and other microbial infections at these sites. PROJECT NARRATIVE: Fungal and other pathogens enter the body through the lung and cause disease at this site or after dissemination. The studies proposed here will create a uniquely powerful transgenic mouse to investigate the induction of protective immune responses in the lung. Our findings will provide the mechanistic basis to design strategies that prevent and/or treat infections with fungi and other microbial infections.

描述（由申请人提供）：真菌病原体和大多数感染因子通过粘膜表面进入人体。粘膜免疫启动诱导全身和粘膜抵抗，并被认为是预防或治疗粘膜表面感染的理想策略。反过来，全身启动通常会导致粘膜免疫不良，并且被认为不太适合抵抗粘膜感染。与此范例相反，我们发现皮炎芽生菌减毒活疫苗株可以保护小鼠免受致命性肺部感染（通过 Th1 CD4+ T 细胞），此时减毒株仅通过皮下途径递送，而不是通过呼吸道递送路线。在这里，我们将研究这 2 种抗原 (Ag) 传递途径在启动和召回阶段触发 CD4+ T 细胞的基本机制。我们将努力揭示导致皮肤和肺部 T 细胞有效或失败启动的细胞和分子机制。 T 细胞受体 (TCR) 转基因 (Tg) 系统可以说是破译体内克隆 T 细胞激活的最佳免疫学工具，但目前还没有此类试剂可用于研究 T 细胞对二态性真菌的免疫。因此，我们建议创建芽生菌特异性 CD4+ TCR Tg 小鼠来监测和分析这两种免疫学不同环境中 Ag 特异性 CD4+ T 细胞的激活。我们假设皮下递送 Ag 将启动皮肤引流淋巴结中的 TCR Tg（胚细胞特异性 CD4+ T 细胞），使其成为激活的 Th1 效应细胞，并在召回时防止肺部攻击。另一方面，粘膜启动将导致功能受损的 Th1 效应器的产生，无法提供对挑战的抵抗力。我们的具体目标是： 1) 开发过继转移系统来监测体内芽生菌特异性 CD4+ T 细胞。真菌特异性 TCR Tg 小鼠将从保护小鼠免受实验感染的 T 细胞克隆中产生。 TCR Tg 细胞将用于建立自体过继转移系统，以跟踪保护性 Ag 特异性 T 细胞在皮肤启动阶段和肺部召回时的表型和功能特性。 2) 确定粘膜启动是否以及如何未能产生 Ag 特异性 Th1 CD4+ 细胞。 TCR Tg 细胞将使我们能够追踪呼吸道粘膜接触 Ag 后 CD4+ T 细胞反应的关键阶段：在启动和回忆阶段，肺和引流淋巴结中的募集、激活、增殖和分化。这些事件将与皮肤接触银后的事件进行比较/对比。 我们的研究将为粘膜组织中 T 细胞反应和免疫的进化提供新的见解。这些知识将有助于制定有效的策略来诱导获得性保护性免疫，从而改善对这些部位真菌和其他微生物感染的控制。 项目叙述：真菌和其他病原体通过肺部进入体内，并在该部位或传播后引起疾病。这里提出的研究将创造出一种独特的强大转基因小鼠，以研究肺部保护性免疫反应的诱导。我们的研究结果将为设计预防和/或治疗真菌感染和其他微生物感染的策略提供机制基础。