细胞毒性T淋巴细胞（CTLs）是通过识别细胞表面与MHC I类分子结合的抗原表位杀伤靶细胞，它是机体抗肿瘤和有效控制各种感染的重要免疫防御反应之一。PRRS是危害养猪业最重要的疾病之一。PRRSV感染宿主后诱导产生的细胞免疫对清除机体病毒可能起着更重要的作用，但目前对其免疫机制缺乏全面系统的了解。M蛋白是PRRSV最为保守的结构蛋白，可诱发强烈的特异性细胞免疫应答。因此本研究以M蛋白为靶标，利用生物信息学方法预测出与长白猪SLA-1等位基因有潜在高亲和力的候选九聚肽，利用体外构建的SLA-I复合体筛选出与SLA-1等位基因特异性结合的表位，通过SLA单倍型仔猪从体内和体外鉴定可被自然加工、递呈的具有免疫学活性的SLA-1限制性CTL表位，并初步探讨其介导的CTL应答在PRRSV感染中的作用以及不同SLA-1等位基因对PRRSV感染的影响，为阐明PRRS细胞免疫机制和研制多肽疫苗奠定基础。

Cytotoxic T lymphocytes (CTLs) can kill target cells by identifying antigen epitopes which bind MHC class I molecules on the cell surface. It is the important immune defense reaction for host to resist the tumors and control all kinds of infections effectively. PRRS is one of the most important diseases that harmed swine industry. Cell-mediated immunity which was induced by PRRSV may play more important role for clearance of virus. However, at present, we still lack systematical and comprehensive understanding of immune mechanisms about PRRS. M protein is highly conservative structural protein of PRRSV and it can induce strong specific cellular immune response. In this study, several peptides of M protein with high affinity to SLA-1 alleles of Landrace will be predicted using the bioinformatics methods and the peptide-binding specificities will be analyzed using the reconstructed SLA class I protein complex in vitro. Immunogenicity of candidate SLA-1 alleles-restricted peptides will be detected in vivo and in vitro using SLA haplotype miniature piglets. The role of CTL response in PRRSV infection and the relationship between SLA-1 alleles and the PRRSV infection will be explored. This study may be lain the foundation for elucidating the cellular immune mechanisms of PRRS and developing multi-peptide vaccines.