[Changes of the expression of histocompatibility (HLA) antigens in human fibroblasts transformed by the avian leukosis-sarcoma virus].

Monoclonal monomorphic antibodies anti-HLA class I and II antigens, were used to evaluate the expression of these molecules on normal and RSV-transformed human fibroblasts. The results indicate that the human diploid fibroblasts transformed in vitro by RSV present a reduced HLA-class I antigens expression as compared to the uninfected fibroblasts of the same donor. In parallel, it is demonstrated that the class II molecules absent on normal cells are expressed after transformation.