Identification of a novel conserved HLA-A*0201-restricted epitope from the spike protein of SARS-CoV

• Main Authors: Ni Bing, Wang Li, Ruan Zhihua, Lv Yanbo, Wu Yuzhang
• Format: Article
• Language: English
• Published: BMC 2009-12-01
• Series: BMC Immunology
• Online Access: http://www.biomedcentral.com/1471-2172/10/61

<p>Abstract</p> <p>Background</p> <p>The spike (S) protein is a major structural glycoprotein of coronavirus (CoV), the causal agent of severe acute respiratory syndrome (SARS). The S protein is a potent target for SARS-specific cell-mediated immune responses. However, the mechanism CoV pathogenesis in SARS and the role of special CTLs in virus clearance are still largely uncharacterized. Here, we describe a study that leads to the identification of a novel HLA-A*0201-restricted epitope from conserved regions of S protein.</p> <p>Results</p> <p>First, different SARS-CoV sequences were analyzed to predict eight candidate peptides from conserved regions of the S protein based upon HLA-A*0201 binding and proteosomal cleavage. Four of eight candidate peptides were tested by HLA-A*0201 binding assays. Among the four candidate peptides, Sp8 (S_958-966, VLNDILSRL) induced specific CTLs both <it>ex vivo </it>in PBLs of healthy HLA-A2⁺donors and in HLA-A2.1/K^btransgenic mice immunized with a plasmid encoding full-length S protein. The immunized mice released IFN-γ and lysed target cells upon stimulation with Sp8 peptide-pulsed autologous dendritic cells in comparison to other candidates.</p> <p>Conclusion</p> <p>These results suggest that Sp8 is a naturally processed epitope. We propose that Sp8 epitope should help in the characterization of mechanisms of virus control and immunopathology in SARS-CoV infection.</p>