Molecular cloning and immunogenicity of renal cell carcinoma-associated antigen G250

The molecular cloning of the cDNA and gene encoding the venal cell carcinom a (RCC)-associated protein G250 is described. This protein is one of the be st markers for clear cell RCC: all clear-cell RCC express this protein, whe reas no expression can be detected in normal kidney and most other normal t issue. Antibody studies have indicated that this molecule might serve as a therapeutic target. In view of the induction/up-regulation of G250 antigen in RCC, its restricted tissue expression and its possible role in therapy, we set out to molecularly define the G250 antigen, which we identified as a transmembrane protein identical to the tumor-associated antigen MN/CAIX. W e determined, by FISH analysis, that the G250/MN/CAIX gene is located on ch romosome 9p12-13. In view of the relative immunogenicity of RCC, we investi gated whether the G250 antigen can be recognized by TIL derived from RCC pa tients. The initial characterization of 18 different TIL cultures suggests that anti-G250 reactivity is rare. (C) 2000 Wiley-Liss, Inc.