Characterization of monoclonal antibodies against sporadic bovine leukosis cell lines.

We report here distributions of antigens expressed on sporadic bovine leukosis (SBL) cells by a total of 38 monoclonal antibodies (mAbs) directed against three different types of SBL-cell lines, BLT2 (thymic type), BTL-PC3 (calf type) and BLS1 (skin type). Most mAbs had high reactivities with some bovine lymphoma cell lines and less reactivity with normal lymphocytes except for some peripheral blood mononuclear cells (PBM) in cattle and certain other species. They were more reactive with cultured T-cell line BTL-PC3 and B-cell lines, BL312 and KU-1, than naturally occurring lymphoid tumor cells. Among the 38 mAbs, 27 was determined the molecular weights of their recognized antigens in Western blot analyses. A mAb C419 had high reactivity with lymphoma cell lines but no reactivity with normal lymphocytes, indicating that it recognizes tumor-associated antigens of SBL.