The study of human melanoma-specific antigen peptides by HLA-A2 restricted tumor-infiltrating lymphocytes / 中国免疫学杂志

ABSTRACT

Objective:To explore the characteristics of human melanoma-specific antigen peptides by HLA-A2 restricted tumor-infiltrating lymphocytes.Methods:The HLA-A2 protein and polypeptides molecules were purified from the three tumor cell lines(624-Mel, Chap-Mel and JY) by immunoaffinity chromatography, after the peptides bound to HLA-A2 protein solution were acidified with acetic acid and boiled by high temperature, and centrifuged through an Ultra-CL filter, then the peptides extracts were fractionated by revered phase high pressure liquid chromatography(RP-HPLC). Individual fractions were assessed for their ability to reconstitute melanoma-specific epitopes by adding to the HLA-A2 Ag-procceing mutant cell, T2. The biological feature of one of three active peptides from RT-HPLC samples was performed by mass spectrometric analysis. The synthetic peptides identical to active peptide sequences were determined in the reconstitute test.Results:Three prominent peaks(P19, P25 and P31) of the fraction from 624-Mel were observed in the reconstitute test, TIL killing rate was 67% for (P31) peptide fraction. The mass spectrometric analysis of one of active peptides (P31) showed that at mass-to-charge ratio(m/z) 948 has been usually nine residues. The sequence is H+ Ala Lue Trp Lue Phe Phe Gly Val Lue OH-. The peptide synthesized comprising epitopes were verified.Conclusion:These results showed the peptides derived from active fractions were related to human melanoma-specific tumor antigen peptides recognized by HLA-A2-restriced TIL. These peptides could develop novel peptide-based an anti-tumor vaccine for immunotherapy of CTL.