One in six people will die of cancer. the systemic nature, recall ability and exquisite specificity of the immune system makes immunotherapy an attractive prospect for cancer treatment. Hepatocellular carcinoma, cervical carcinoma, various leukemias and lymphomas all have proposed viral etiologies. Viral encoded tumor specific antigens make viral associated tumors strong candidates for immunotherapy. Recent studies have described the presence of simian virus 40 (SV40)-like gene sequences and proteins (specifically the large tumor antigen: SV40 Tag) in human osteosarcomas, glioblastomas, ependymomas and malignant pleural mesotheliomas (MPM), demonstrating SV40 association with certain human malignancies. To facilitate the development of human clinical protocols for the immunotherapy of SV40 associated human malignancies, the proposed study will employ an SV40 murine tumor system to evaluate the efficacy of CTL transfer therapies and peptide based vaccines designed to target an immune response to SV40 Tag expressing tumors in vivo. Briefly, SV40 Tag specific CTL will be generated by immunization of Balb/c mice with SV40 Tag gene constructs and the epitope specificity determined by using selected H-2d restricted synthetic peptides representing potential CTL epitopes on SV40 Tag. These CTL will be utilized to examine the ability of adoptively transferred T cells to protect against tumor challenge in syngeneic mice. Further, selected synthetic peptides will be examined for the ability to actively induce protective tumor immunity in vivo. Completion of this study will provide valuable information on the active induction of tumor destructive immunity involving SV40 Tag-epitope specific CTL in vivo. Moreover, the information generated using the murine SV40 tumor model will expedite the development of reagents and clinical trials designed to examine SV40 Tag specific immunotherapies for SV40 associated human malignancies.
