Vaccination with an NY-ESO-1 peptide of HLA class I/II specificities induces integrated humoral and T cell responses in ovarian cancer.

NY-ESO-1 is a "cancer-testis" antigen expressed in epithelial ovarian cancer (EOC) and is among the most immunogenic tumor antigens defined to date. The NY-ESO-1 peptide epitope, ESO(157-170), is recognized by HLA-DP4-restricted CD4+ T cells and HLA-A2- and A24-restricted CD8+ T cells. To test whether providing cognate helper CD4+ T cells would enhance the antitumor immune response, we conducted a phase I clinical trial of immunization with ESO(157-170) mixed with incomplete Freund's adjuvant (Montanide ISA51) in 18 HLA-DP4+ EOC patients with minimal disease burden.