6B11抗独特型单链抗体－热休克蛋白70融合蛋白诱导抗卵巢癌免疫应答的体外实验研究

BSTRACT Objective: It has been improved that 6B11 anti-idiotypic single chain antibody can mimic OC166-9, the antigen of ovarian carcinoma in our previous researcch. In this study we are going to evaluate whether anti-tumor immune response can be induced by the fusion protein of B11ScFv-mHSP70 in vitro. And to explore the probability of 6B11ScFv-mHSP70 as ovarian cancer vaccine. Methods: 6B11ScFv-mHSP70 was expressed by E.coli and the fusion protein was more than 95% in the production after denaturation and renaturation. The immunological activities of 6B11ScFv-mHSP70 was analyzed with ELISA and inhibiton ELISA respectively. Separated female peripheral blood mononuclear cells (PBMC) expressing HLA-A2 were co-cultured and stimulated with 6B11ScFv-mHSP70. The proliferations of PBMC and cytotoxicity were observed by CCK-8 and LDH release test respectively. Immune Flow Cytometry was used to analyze the phenotype of T lymphocyte stimulated by 6B11ScFv-mHSP70. Result: 6B11ScFv-mHSP70 showed capacity of binding to ovarian cancer monoclonal antibody COC166-9 and anti-mHSP70 antibody. It also could stimulate PBMC to be proliferated and performed cytotoxicity function to ovarian carcinoma cell line expressing OC166-9 and HLA-A2. There were significant difference between stimulation and unstimulation in CD4+ T cell, CD8+ T cell, CD4+/CD8+ ratio and Treg cell. Conclution: 6B11ScFv-mHSP70 can induce cellular immunity against ovarian carcinoma in vitro. This paper has provided experimental evidence for clinical use of 6B11ScFv-mHSP70 as anti-idiotype vaccine against ovarian carcinoma.