Intracellular localization of tumor-associated antigens in murine and human malignant melanoma

Cross-reacting tumor-associated antigens have been demonstrated to be present in the cytoplasm of melanocytes in malignant melanoma. We have utilized both the leukocyte migration inhibition and the lymphocyte stimulation assays to determine the intracellular location(s) of these antigens in both human malignant melanoma and B-16 murine melanoma. The results of both assays indicate that this antigen(s) is associated with the membranous organelles, particularly the melanin granules, and is not found in the soluble components of the cytoplasm, as suggested by other studies.