studies of antigen presentation of peptides by MHC class I molecules

点击翻译按钮获取中文摘要

1.We found that assembly rate of HLA-B35 molecules is faster than that of HLA-B51 molecules. One can speculate that the difference of peptide binding affinity to these HLA class I molecules result in that of assembly rate. To investigate peptide binding to HLA class I molecules, we established novel binding assay using RMA-S cells trasnfected with HLA class I genes. Analysis of binding of peptides carrying anchor residues of HLA-B35 or B51 to these HLA class I molecules indicate that the peptide binding affinity to HLA-B51 is significantly weaker than that to HLA-B35. These findings imply that the difference of assembly rate may result from that of peptide binding to these HLA class I molecules in endoplasmic reticurum.2.In order to clarify self-peptides recognized by T cells, we attempted to isolate allopeptides recognized by HLA-B51 alloreactive CTL.In HPLC fraction of peptides isolated from purified HLA-B51 molecules, a TAP dependent peptide recognized by one HLA-B51 alloreactive CTL clone was detected. This approach is very useful for studies of antigen presentation and T cell recognition.3.Polymorphism and antigen presentation of human minor histocompatibility (hmH) antigens were studied using hmH specific CTL clones. The CTL clones killed most target cells expressing HLA-B35, while they failed to kill the cells expressing HLA-B35 subtypes. Since the specific hmH peptides could be isolated form these cells expressing HLA-B35 subytypes, hmH antigens are thought to be conserved among populations.