A new gene coding for a differentiation antigen recognized by autologous cytolytic T lymphocytes on HLA-A2 melanomas.

TLDR

Antitumor CTL clones can be isolated from HLA‑A2 melanoma patients and lyse most HLA‑A2 melanomas, with the tyrosinase gene previously identified as a target antigen. The study identifies Melan‑A, an 18‑kb, five‑exon gene expressed in most melanomas and melanocytes, as a new HLA‑A2–restricted antigen recognized by CTL clones.

Abstract

It has been reported previously that antitumor cytolytic T lymphocyte (CTL) clones can be isolated from blood lymphocytes of HLA-A2 melanoma patients, after stimulation in vitro with autologous tumor cells, and that some of these CTL clones lyse most HLA-A2 melanomas. A first antigen recognized by such CTL clones was previously shown to be encoded by the tyrosinase gene. We report here the identification of another gene that also directs the expression of an antigen recognized on most melanomas by CTL clones that are restricted by HLA-A2. The gene, designated Melan-A, is unrelated to any known gene. It is 18 kb long and comprises five exons. Like the tyrosinase gene, it is expressed in most melanoma tumor samples and, among normal cells, only in melanocytes.