PREDOMINANT EXPRESSION OF T-CELL RECEPTOR-V-ALPHA-7 IN TUMOR-INFILTRATING LYMPHOCYTES OF UVEAL MELANOMA

Expression of T cell receptor (TCR) Vα genes in tumor-infiltrating lymphocytes (TILs) within intraocular melanoma was studied. Primers for 18 different human TCR Vα families were used to analyze TCR Vα-Cα gene rearrangements in TIL in these melanomas obtained at surgery. A limited number of TCR V α genes were expressed and rearranged in these tumors, and TILs expressing Vα7 were found in seven of eight of these uveal melanomas. TCR gene usage is also restricted in experimental autoimmune disease, in T cells within organs like skin and other epithelial tissues, and in the brain of patients with multiple sclerosis (MS). The restricted usage of TCR genes in TIL may indicate that a specific antigen in these melanomas is targeted.