CYTOTOXIC T-LYMPHOCYTES RAISED AGAINST A SUBDOMINANT EPITOPE OFFERED AS A SYNTHETIC PEPTIDE ERADICATE HUMAN PAPILLOMAVIRUS TYPE 16-INDUCED TUMORS

Previously, we have shown that immunization with human papillomavirus (HPV) type 16-derived cytotoxic T lymphocyte (CTL) epitope E7 49-57 (R AHYNIVTF) renders C57BL/6 mice insensitive to tumors formed by HPV16-t ransformed cells. In this study, we provide evidence that E7 49-57 is expressed as a subdominant CTL epitope on HPV16-transformed C57BL/6 ce lls, Using acid peptide elution, it is shown that HPV16-transformed ce lls express another CTL epitope, besides E7 49-57, which appears to be dominant, We demonstrate that a CTL line raised against the subdomina nt CTL epitope, offered as synthetic peptide E7 49-57, eradicates esta blished HPV16-induced tumors in mice. Our data show that synthetic pep tide-induced CTL can be applied successfully in vivo against (virus-in duced) tumor, and emphasize that subdominant CTL epitopes are useful t argets for immunotherapy. Furthermore, it is illustrated for the first time that HPV16-specific CTL interfere directly with HPV16-induced tu mors.