Initial characterization of monoclonal antibodies against human monocytes.

Three monoclonal antibodies against human monocytes have been produced by somatic cell fusion. Extensive specificity analysis suggests that these antibodies react with most if not all human peripheral blood monocytes and not with highly purified T or B cells. Initial chemical characterization of the monocyte antigen recognized by two of these antibodies is presented. The molecule is a single polypeptide chain with an apparent molecular weight of 200,000. These reagents should prove useful in the clinical definition of disorders of monocyte differentiation, in studies of monocyte function, and in the elucidation of the genetics and structure of monocyte cell surface antigens.