Human T-cell Epitopes in SARS

描述（由申请人提供）：由于基因组大小较大且HLA等位基因的极端多态性，因此发现和验证源自严重急性呼吸道综合征冠状病毒（SARS CoV）的HLA限制性细胞毒性和辅助T细胞表位是一项重大挑战。在此，我们提出将联合收割机生物信息学方法和高通量MHC-肽结合测定相结合，以鉴定代表>95%的一般人群的HLA I类和II类分子限制的表位，而不考虑种族。这些表位将通过使用来自健康未暴露供体的HLA转基因小鼠和人PBMC的体内和体外免疫原性研究进一步验证。动物模型可能在SARS特异性疫苗和诊断方法的开发中发挥重要作用。因此，我们还计划鉴定在人MHC转基因小鼠中表达的小鼠和人MHC分子呈递的表位。在本申请的最后部分，我们提出探索多表位SARS疫苗构建体的开发。该构建体可以单独使用，或与旨在诱导抗SARS抗体应答的其他疫苗构建体结合使用。因为所提出的方法是基于SARS衍生肽序列的免疫原性潜力的系统定义，所以只需要最小限度地使用来自感染或康复个体的活SARS病毒或生物样品。本文提出的研究将导致广泛的表位的定义，促进严格评估与人类感染相关的T细胞应答所需的诊断试剂的开发，并能够在T细胞免疫水平上评估不同候选疫苗的性能。

DESCRIPTION (provided by applicant): The discovery and validation of HLA-restricted cytotoxic and helper T cell epitopes derived from the Severe Acute Respiratory Syndrome coronavirus (SARS CoV) represents a significant challenge because of the large genome size and because of the extreme polymorphism of HLA alleles. Herein, we propose to combine bioinformatic approaches and high throughput MHC- peptide binding assays to identify epitopes restricted by HLA class I and class II molecules representative of >95% of the general population, irrespective of ethnicity. These epitopes will be further validated with in vivo and in vitro immunogenicity studies utilizing HLA transgenic mice and human PBMC from healthy unexposed donors. Animal models are likely to play a vital role in the development of SARS specific vaccines and diagnostics. Accordingly, we also plan to identify epitopes presented by mouse and human MHC molecules expressed in human MHC transgenic mice. In the final part of this application, we propose to explore development of a multi-epitope SARS vaccine construct. This construct could be utilized by itself, or in conjunction with other vaccine constructs aimed at inducing anti-SARS antibody responses. Because the proposed approach is based on a systematic definition of the immunogenic potential of SARS-derived peptide sequences, only minimal use of live SARS virus or biological samples from infected or convalescent individuals is required. The studies proposed herein will lead to the definition of a broad range of epitopes, facilitate the development of diagnostic reagents necessary to rigorously evaluate T cell responses associated with infection in humans, and enable the evaluation, at the level of T cell immunity, of the performance of different vaccine candidates.