点突变p53肽诱导肽特异性CTL的研究

Induction of peptide specific cytotoxic lymphocytes with a mutant p53 peptide

目的探索点突变ｐ５３肽诱导细胞免疫应答的可能性，为其作为肽疫苗用于肿瘤免疫治疗提供实验依据。方法人工合成小鼠点突变ｐ５３肽Ｐ１３２Ｆ（ＬＮＫＬＦＦＱＬ，１３２Ｃｙｓ→Ｐｈｅ突变），与不完全弗氏佐剂（ＩＦＡ）或ＲＩＢＩ佐剂（ＲＡＳ）混合，皮下免疫Ｃ５７ＢＬ／６小鼠，分离脾细胞体外用肽再刺激，诱导细胞毒Ｔ淋巴细胞（ＣＴＬ），并以５１Ｃｒ释放法检测其杀伤活性。结果Ｐ１３２Ｆ肽加上ＩＦＡ或ＲＡＳ免疫小鼠，均能诱导肽特异性ＣＤ８＋ＣＴＬ；低剂量重组白细胞介素２（ｒＩＬ－２）能增强肽免疫效果。结论所用突变的ｐ５３蛋白具有免疫原性。

Objective To explore the possibility of inducing cell-mediated immune response with p53 peptides. Methods A mouse mutant p53 peptide, P 132F (LNKLFFQL, with a mutation of 132Cys→Phe), was synthesized. C57BL/6 mice were subcutaneously immunized with P 132F in adjuvant IFA or RAS, and spleen cells of the primed mice were restimulated in vitro with the peptide to generate cytotoxic T lymphocytes (CTL). The cytotoxicity of the CTL was detected by 51 Cr release assay. Results It was found that peptide specific CD8 + CTL responses were readily elicited by immunization with P 132F mixed with either IFA or RAS, and that low dose of rIL 2 helped enhance induction of peptide specific CTL. Conclusion The results suggest that mutant p53 protein is immunogenic and that antigenic peptides derived from the protein may be used as peptide vaccines for cancer immunotherapy.