Mouse mononuclear phagocyte antigenic heterogeneity detected by monoclonal antibodies.

Identification and characterization of the many cellular and subcellular changes that underlie various macrophage functions have been hampered by the problem of population heterogeneity. The problem has remained because, in the case of most functions, we have not had the means to examine cells at a level below that of whole populations. We report here the potential means to do so. Rat anti-mouse mononuclear phagocyte monoclonal antibodies were raised against adherent cells cultured from bone marrow. These antibodies were used to delineate and, in the presence of complement, eliminate subpopulations of macrophages. The extent to which antigenic heterogeneity occurs was shown in several mononuclear phagocyte populations that are commonly employed experimentally. Some antibodies reacted with most mononuclear phagocytes tested, whereas others showed marked selectivity of binding. As expected, resident populations were less heterogeneous antigenically than inflammatory populations were. The data both extend what is known about mononuclear phagocyte population heterogeneity and suggest means by way of which this heterogeneity can be overcome.