HTLV-I infection and chronic lymphocytic leukemia

We have captured the immunoglobulin genes of CLL cells by fusing the peripheral blood lymphocytes from CLL cells with the B lymphoblastoid line. The hybridoma cell line established from the fusion of CLL cell from two patients who were HTLV-I seropositive produced antibody directed against HTLV-I proteins. The antibody activity of the immunoglobulin produced by the fused cells is different in the two patients in one case being directed against a gag protein and in the other against the viral large envelope protein. In an attempt to explore possible mechanisms whereby HTLV-I may contribute indirectly to the pathogenesis of B cell CLL, we have determined that B cell lines infected with HTLV-I produce growth factor(s) which stimulate and expand populations of normal B cells as well as CLL cells. These results suggest that HTLV-I infection may contribute in several ways to the development of a malignancy in cell where the virus is not present in the cellular genome.