Monocytes/macrophages in diagnosis and immunopathogenesis.

Abstract

This article summarizes studies of human monocytes/macrophages carried out in my laboratory over a period of more than three decades. Modern studies of mammalian phagocytes began with Metchnikoff in the late 19th century. The early history of this field is summarized in Table ​Table1.1. In vivo and in vitro studies in animal systems led to the concept of the mononuclear-phagocyte system as a cell system involved in host defenses, phagocytosis, and antigen presentation and processing (11). Following Metchnikoff’s development of phagocyte theory, Wright described opsonins as factors in serum that facilitated phagocytosis. Aschoff defined the reticuloendothelial system as a cellular system in which tissue macrophages and monocytes share important functional characteristics, namely, phagocytic ability and adhesiveness to glass. Subsequently, the histologic development of silver stains by Del Rio-Hortega defined a type of macrophage-related cell in the brain, the microglia. In the mid-1960s, the late Zanvil Cohn and his collaborators carried out seminal studies of mononuclear phagocytes leading to concepts of macrophage differentiation, activation, secretion, and the relationship of macrophages to antigen presentation and processing. My laboratory has had a long-standing commitment to the investigation of human monocytes/macrophages, their normal structure and function, their role in the immunopathogenesis of various disorders, and their functional abnormalities in diseases. TABLE 1 Early history of research on mononuclear phagocytes (This report was presented as the Abbott Award Lecture in Clinical and Diagnostic Laboratory Immunology at the 97th General Meeting of the American Society for Microbiology, Miami, Fla., May 1997.)