A preparation of autologous CD8+ (cytotoxic) human peripheral blood lymphocytes (PBLs) sensitized to Drosophila cell-presented melanoma peptides, with potential immunostimulating and antineoplastic activities. Autologous CD8+ T-lymphocytes, isolated from a melanoma patient, are exposed in vitro to melanoma peptide-pulsed HLA-A2-expressing Drosophila cells, expanded, and reintroduced into the patient; these tumor-reactive T-cells may stimulate a host immune response against tumor cells expressing the melanoma antigens, resulting in tumor cell lysis. Drosophila cells, which do not express any native MHC molecules, have been shown to potently stimulate tumor-reactivity in vitro from human peripheral blood lymphocytes (PBL) when stably transfected with human MHC molecules and appropriate adhesion and costimulatory molecules.