Immunity against fungal infections

项目摘要 尽管真菌感染在全球范围内呈上升趋势， 包括地方性物种 .,没有许可的真菌疫苗 available.这主要是由于对疫苗免疫机制的认识不足， 的功能 表型标记 疫苗效力真菌性感染，包括由 二型真菌，组织胞浆菌，球孢子菌和芽生菌，正在以惊人的速度上升，在这样的风险 个体为高危人群开发定制真菌疫苗的一个主要限制是贫穷 了解 CD 8 + T细胞应答的必要元素，以介导疫苗免疫。 的最新进展 对抗真菌感染的免疫相关性的理解有助于平行地推进疫苗学。 T细胞衍生的IL-17 A、IFNγ、GM-CSF、IL-22和TNFα主要参与抗真菌保护。 鉴定宿主细胞上的潜在靶标可以提供新的有效疫苗平台，包括用于 免疫力低下我们建立了一种小鼠CD 4 + T细胞淋巴细胞减少症模型，其中CD 8 + T细胞 可刺激产生保护性细胞因子IL-17 A（Tc 17）和IFNγ（Tc 1）以执行杀菌免疫 对抗致命的肺部真菌感染我们已经表明，疫苗诱导的抗真菌CD 8 + T细胞持续存在， 作为长期功能记忆。在这项建议中，我们提出了开创性的发现：1。GM-CSF+ Tc 17细胞支持物 无病理的疫苗免疫; 2.抗真菌CD 8 + T细胞优先表达O-糖基化 唾液酸蛋白;和3.唾液酸蛋白是CD 8 + T细胞分化和扩增所必需的。所以我们的 中心假设是：（1）唾液酸蛋白作为CD 8 + T细胞应答的共刺激物，（2）保留CD 8 + T细胞， 唾液酸蛋白是记忆CD 8 + T细胞稳态和回忆反应所必需的。（3）唾液酸蛋白信号传导 增强交叉呈递以增强CD 8 + T细胞应答。我们的具体目标是：1.确定和 剖析唾液酸蛋白对于CD 8 + T细胞真菌疫苗应答的作用。我们会破译并描绘出这个细胞- 唾液酸蛋白对疫苗诱导Tc 17和Tc 1细胞应答内在作用（采用过继转移和骨- 骨髓嵌合体实验，以及使用TCRα KO、Sialophorin KO小鼠的同源和杂交。2.阐明 唾液酸蛋白在真菌性肺炎期间记忆T细胞稳态和回忆反应中的作用。我们将 确定唾液酸蛋白在疫苗诱导的记忆CD 8 + T细胞稳态、回忆反应中的作用， 疫苗免疫我们将在体内使用骨髓嵌合体，过继转移，CRISPR-Cas9基因编辑， 刺激和E-选择素阻断来描绘唾液酸蛋白对记忆性CD 8 + T细胞应答的作用。3. 剖析唾液酸蛋白在树突状细胞上对于CD 8 + T细胞真菌疫苗应答的作用。 我们将确定 抗原呈递细胞上的CD 43在疫苗接种后活化CD 8 + T细胞中的作用 .我们的发现将 揭示唾液酸蛋白对真菌CD 8 + T细胞应答和免疫的功能作用，以指导设计 新型疫苗平台的开发和疫苗效力的测试。

PROJECT SUMMARY Despite the global rise in fungal infections, including those by endemic sp ., there is no licensed fungal vaccine available. This is mainly due to poor understanding of mechanisms of vaccine immunity, and lack of a functional phenotypic marker associated with vaccine efficacy. Opportunistic fungal infections, including those caused by dimorphic fungi, Histoplasma, Coccidiodes and Blastomyces, are rising at an alarming rate in such at-risk individuals. A major limitation in the development of tailored fungal vaccines for the at-risk population is poor understanding of requisite elements of CD8+ T cell responses to mediate vaccine-immunity. Recent advances in the understanding of immune correlates against fungal infections has helped in advancing vaccinology in parallel. T-cell derived IL-17A, IFNγ, GM-CSF, IL-22, and TNFα are primarily involved in protection against fungi. Identification of potential targets on host cells can provide novel efficacious vaccine platforms, including for immunocompromised. We have established a mouse model of CD4+ T cell lymphopenia, where CD8+ T cells can be stimulated to produce protective cytokines IL-17A (Tc17) and IFNγ (Tc1) to execute a sterilizing immunity against lethal pulmonary fungal infection. We have shown that vaccine-elicited antifungal CD8+ T cells persisted as long-term functional memory. In this proposal, we present seminal findings: 1. GM-CSF+ Tc17 cells bolster vaccine-immunity without pathology; 2. Anti-fungal CD8+ T cells preferentially express O-glycosylated Sialophorin; and 3. Sialophorin is required for differentiation and expansion of CD8+ T cells. Therefore, our central hypotheses are that (1) Sialophorin acts as a co-stimulator for CD8+ T cell responses, (2) retention of Sialophorin is essential for memory CD8+ T-cell homeostasis and recall responses, (3) Sialophorin signaling potentiates cross-presentation to augment CD8+ T cell responses. Our specific aims are to: 1. Determine and dissect the role of Sialophorin for CD8+ T-cell fungal vaccine responses. We will decipher and delineate the cell- intrinsic role of Sialophorin for vaccine-induced Tc17 and Tc1 cell responses using adoptive transfer and bone- marrow chimera experiments, and using TCRα KO, congenic and crosses of Sialophorin KO mice. 2. Elucidate the role of Sialophorin for memory T cell homeostasis and recall responses during fungal pneumonia. We will define the role of Sialophorin for vaccine-induced memory CD8+ T-cell homeostasis, recall responses, and vaccine-immunity. We will use bone marrow chimera, adoptive transfers, CRISPR-Cas9 gene-editing, in vivo stimulation, and E-selectin blocking to delineate the role of Sialophorin on memory CD8+ T-cell responses. 3. Dissect the role of Sialophorin on dendritic cells for CD8+ T-cell fungal vaccine responses. We will identify the role of CD43 on antigen-presenting cells for activation of CD8+ T cells following vaccination . Our findings will uncover the functional role of Sialophorin for fungal CD8+ T-cell responses and immunity to guide in the design of novel vaccine platforms and test the efficacy of vaccines.