HLA peptidomics and personalized cancer immunotherapy

Presentation of tumor-specific HLA peptides may cause can be exploited for the elimination of the diseased cells, when used as cancer vaccines. Extensive efforts are made to identify HLA peptides derived from cancer-specific proteins that are not expressed by any of the normal/essential cells in the body, to be administered as immunotherapeutics for cancer, without the fear of inducing adverse effects. The most important cancer candidates are Cancer/Testis Antigens, which are proteins that are expressed only in the germline cells or in embryonal tissues, and neoantigens, which are expressed only in the cancer cells since they contain mutated sequences unique to the cancer cells. The approach we take is to combine the commonly used exome analyses of the tumor and normal cells with and transcriptome and HLA peptidome analyses of the tumor cells alone and look among the identified peptides for those that are derived from Cancer/Testis antigens and neoantigens. This approach can identify from among the thousands of possible candidate peptides, those few that are really produced and presented by the cancer cells and prioritize them for further immunogenicity testing and clinical applications