Objective To isolate and identify peptides bound to HLA I onhuman hepatocellular carcinoma. Methods MHC-associated peptides were extracted by mild acid wash of viable hepatocellular carcinomas cells, collected by gel filtration, and fractioned by reversed phase high pressured liquid chromatography (RP-HPLC). Peptides of individual fractions were reconstitution of T cell epitopes and were identified by cytotoxicity T lymophacyte assay. Actively extracted sample analyses were performed by HPLC-MS-MS (tandom mass spectrometry). Protein database in the internet was used as an additional tool for structure analysis and for determination of protein source of the eluted peptides. Result RP-HPLC showed that there were over 20 different fractions of peptides derived from human hepatocellular carcinoma, and only two active peaks were identified by cytotoxicity T lymophocyte assay. The most promising candidate for T cell epitope was nonamers peptide (SLIVHLNEV), derived from met/hepatocyte growth factor receptor, point mutation was 1180F to L. Conclusion Sensitive sequencing by HPLC-MS may provide a powerful method of identifying tumor specific antigenic peptides, and nonamers peptide (SLIVHLNEV) is the hepatocellular carcinoma antigenic peptide.%目的 寻找肝癌细胞抗原肽。方法 应用细胞膜酸洗技术使抗原肽从人肝癌细胞膜表面脱落，经过凝胶层析，应用反相高效液相色谱层析得到不同组份多肽，细胞表位重建及生物学鉴定确定其活性，高效液相色谱-质谱仪联用技术获得抗原肽的一级结构，在互联网上进行氨基酸同源性分析确定其同源性序列。结果 经过反相高效液相色谱层析后可以获得20多个多肽组份，生物活性鉴定有2个活性组份，其中1个组份经过液质联用鉴定和氨基酸同源性分析，确定其序列为SLIVHLNEV，是肝细胞生长因子受体前体第1175～1183肽段发生突变，第1180位点的苯丙氨酸变为亮氨酸。结论 液质联用技术为寻找抗原肽的有效方法，肝细胞生长因子受体突变肽SLIVHLNEV为肝癌抗原肽。
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