Rational development of tumour antigen-specific immunization in melanoma

The identification and molecular characterization of antigens expressed on tumour cells, but not on most normal host tissues, has opened the possibility of specific immunization in the therapy of cancer, particularly of melanoma. Most antigens defined are class I MHC-binding peptides recognized by CD8+ cytolytic T lymphocytes (CTL). Methodologies for active immunization to induce effective anti-tumour CTL are under development in a number of laboratories, and some of these approaches have entered clinical trials. Optimization of the anti-tumour immune response will depend on a thorough knowledge of the signals required for T cell activation, differentiation, and inactivation.