Apostolopoulos V, Karanikas V, Haurum J S, McKenzie I F
The Austin Research Institute, Heidelberg, Victoria, Australia.
J Immunol. 1997 Dec 1;159(11):5211-8.
HLA-A0201/Kb transgenic mice were immunized with oxidized mannan-mucin 1 (MUC1) as a fusion protein (containing five repeats of the 20-amino-acid MUC1 VNTR (variable number of tandem repeats) that generated highly active CD8+ CTLs to MUC1 peptides. In a direct CTL assay, the MUC1 peptides could be presented specifically by both the transgenic murine HLA-A0201/Kb and human HLA-A0201 molecules. The 9-mer MUC1 peptide sequences (APDTRPA and STAPPAHGV) were presented by HLA-A0201, although they did not contain L at P2 and L/V at P9, the preferred motifs; as a consequence, the binding was of relatively low affinity when compared with a high affinity-binding HIV peptide (ILKEPVHGV). In addition, when mice were immunized separately with the HLA-A0201-binding peptides (STAPPAHGV or APDTRPAP-containing peptides-keyhole limpet hemocyanin-mannan), direct lysis of MCF-7 (HLA-A0201+, MUC1+) also occurred. The findings are of interest for tumor immunotherapy, particularly as the CTLs generated to low affinity-binding peptides were highly active and could specifically lyse an HLA-A*0201+ human breast cancer cell line without further in vitro stimulation. The findings demonstrate that the range of peptides that can generate CTLs is broader than formerly considered.
用氧化甘露聚糖 - 粘蛋白1（MUC1）作为融合蛋白免疫HLA - A0201/Kb转基因小鼠（该融合蛋白包含20个氨基酸的MUC1可变串联重复序列（VNTR）的五个重复序列，可产生对MUC1肽具有高活性的CD8 + CTL）。在直接CTL测定中，MUC1肽可由转基因鼠HLA - A0201/Kb和人HLA - A0201分子特异性呈递。9聚体MUC1肽序列（APDTRPA和STAPPAHGV）由HLA - A0201呈递，尽管它们在P2处不包含L且在P9处不包含L/V（这是优选基序）；因此，与高亲和力结合的HIV肽（ILKEPVHGV）相比，其结合亲和力相对较低。此外，当用与HLA - A0201结合的肽（含STAPPAHGV或APDTRPAP的肽 - 钥孔血蓝蛋白 - 甘露聚糖）分别免疫小鼠时，也会发生对MCF - 7（HLA - A0201 +，MUC1 +）的直接裂解。这些发现对于肿瘤免疫治疗具有重要意义，特别是因为针对低亲和力结合肽产生的CTL具有高活性，并且无需进一步体外刺激即可特异性裂解HLA - A*0201 +人乳腺癌细胞系。这些发现表明，能够产生CTL的肽的范围比以前认为的更广泛。
