""""""""DISCONTINUED T cells can be activated by antigen-presenting cells. These antigen-presenting cells can provide multiple signals to activate T cells. The first signal is the interaction between the T cell receptor and a specific antigen presented in the context of an appropriate HLA class (HLA Class I for CD8+ T cells and HLA Class II for CD4+ T cells). The second signal is also usually provided by the antigen-presenting cell. One of the strongest second signals is induced by B7. We introduced the gene encoding B7 (CD28 ligand) into 3 human melanoma cell lines that are HLA-A2+ or HLA-A1+, express significant levels of LFA-3 and ICAM-1 and produce RNAs encoding the shared melanoma antigens MAGE-1 and -3, and tyrosinase. The objectives of the study are: 1) determine the maximum number of B7-transfected allogeneic melanoma cells that can be administered SQ or ID, 2) characterize the immune response to B7- transfected cells, and 3) characterize the toxicity, and 4) observe any antitumor responses. Stage IV pts. with melanoma will be typed for expression of HLA-A2 or HLA-A1. The 3 lines will be injected at 2 wk. intervals for 3 vaccinations followed by 3 injections at monthly intervals. Cohorts of pts. will receive escalating doses of 10E7 cells and 10E8 cells SQ. A final cohort will receive 10E7 cells intradermally. Twenty-eight pts. have been vaccinated. There has been 1 CR and 10 pts. with stable disease. The only toxicity has been local skin reactions. Preliminary immunologic monitoring shows that some patients have increased cytotoxic T cell lymphocyte precursors to the melanoma cell lines present in the vaccine. This study was transferred from the CRB to the MB in 1996.""""""""
