Human melanoma cells bear antigens that are recognized by autologous CD8+ cytotoxic T-lymphocytes. The invention involves the reception of particular peptides analogues of the MZ2-E antigen by HLA molecules. Disclosed herein are peptide analogues of the tumor antigen MZ2-E that have been modified to resist peptidase degradation, and which bind HLA molecules to form a complex whose recognition by specific cytolytic T cells leads to lysis of the complex. The identification by cytolytic T cells of the peptide analogue/HLA complex may be used in diagnostics, or therapeutically.