[Spectrum of reactivity of monoclonal antibodies against specific T-suppressors]

Abstract

Monoclonal antibodies (MoAb) against specific T-suppressors CI and C4 are characterized by their reactivity with normal lymphoid cells and some tumour cell lines cultivated in vitro. MoAb CI and C4 react with T and B cells from spleen and lymph nodes. The amount of CI and C4 T and B subsets are equal in the spleen (25-29%), while lymph node T-lymphocytes contain twice as much CI and C4 cells than B-lymphocytes (40 and 20%, respectively). In the thymus CI is expressed mostly on immature (cortical) thymocytes and C4--on the mature (medullary) thymocytes. CI is expressed on some T-lymphoma cell lines (BW 5147, EL4, LBRM33), but not on thymoma RDM4 and mastocytoma P815. C4 is not found on the above cell lines but is expressed on the intermediate filament of mouse and quail fibroblasts and in lymphoid cells. This cross-reactivity may result from the existance of similar determinants in cytoskeleton proteins and lymphocyte membranes or from the intermediate filament expression on T-suppressor cellular membranes, but not on other functional T subsets.