A Gene Encoding an Antigen Recognized by Cytolytic T Lymphocytes on a Human Melanoma

TLDR

Many human melanoma tumors express antigens that are recognized by patient‑derived cytolytic T lymphocytes. The study proposes that antigen MZ2‑E–targeted immunotherapy could be offered to patients identified by HLA typing and tumor RNA analysis. A novel gene encoding antigen MZ2‑E was identified; it is expressed in melanoma and some other tumors, absent in normal tissues, presented by HLA‑A1, and recognized by patient‑derived CTLs.

Abstract

Many human melanoma tumors express antigens that are recognized in vitro by cytolytic T lymphocytes (CTLs) derived from the tumor-bearing patient. A gene was identified that directed the expression of antigen MZ2-E on a human melanoma cell line. This gene shows no similarity to known sequences and belongs to a family of at least three genes. It is expressed by the original melanoma cells, other melanoma cell lines, and by some tumor cells of other histological types. No expression was observed in a panel of normal tissues. Antigen MZ2-E appears to be presented by HLA-A1; anti-MZ2-E CTLs of the original patient recognized two melanoma cell lines of other HLA-A1 patients that expressed the gene. Thus, precisely targeted immunotherapy directed against antigen MZ2-E could be provided to individuals identified by HLA typing and analysis of the RNA of a small tumor sample.