IN-SITU T-CELL RESPONSES IN A PRIMARY REGRESSIVE MELANOMA AND SUBSEQUENT METASTASES - A COMPARATIVE-ANALYSIS

In an earlier study of the immune response in a patient with a cutaneo us primary regressive melanoma, a T-cell-receptor diversity analysis d emonstrated in site amplification of certain lymphocytes, Two of them could be cloned and characterized as CD8(+) HLA-class-I-restricted CTL with strong selective anti-tumor activity. Following a disease-free p eriod of 3 years, the patient developed a gastric metastasis and subse quently (after an additional year) a metastasis in one axillary lymph node, Melanoma cell lines derived from the 2 secondary lesions have be en established here, It was found that these metastatic cells have mai ntained expression of both HLA-class-I molecules and the peptidic anti gen(s) recognized by the 2 clones amplified at the primary site, Howev er, the corresponding T lymphocytes were either undetectable or poorly represented both in the gastric and in the axillary lesions. These re sults suggest that substantial alterations in the quality of T-cell in filtrates occurred during melanoma progression, despite an apparent st ability in presentation of tumor-associated antigen(s) which initially triggered a positive rejection response. (C) 1997 Wiley-Liss, Inc.