The phagocytic cell: summary.

Abstract

A symposium entitled, The Phagocytic Cell was held in Detroit, Michigan, on May 30, 1983, under the sponsorship of the American Association for the Advancement of Science. It was the purpose of this symposium to highlight recent advances in the biology of phagocytes, including (1) the use of monoclonal antibodies in the identification and purification of cell surface structures involved in activation and/or modulation of phagocytic function; (2) the biochemical nature and pathologic consequences of certain phagocytic cell defects; (3) autoregulation of receptor-mediated functions of phagocytes; (4) identification of mechanisms whereby phagocytes express their antimicrobial properties; (5) the modulation of normal phagocytic cell function by bacterial products; and (6) the role of the phagocyte in host defense in the oral cavity. Several of the topics discussed during this symposium are reviewed herein. There is now convincing evidence that phagocytes possess the capacity to regulate in a highly selective manner various receptor-mediated responses. It has been recognized for some years that the receptors for synthetic N-formylmethionyl chemotactic peptides and for C5a mediate both chemotactic responses and lysosomal discharge following ligand-receptor interaction. Although both chemotactic and secretory responses use the same receptor, it is clear that chemotaxis by neutrophils can be elicited with 10-fold-lower concentrations of chemoattractant than are required to provoke lysosomal degranulation. Studies using radiolabelled chemotactic peptides indicate that such