The Biochemical and Antimicrobial Activities of the Phagocyte

Abstract

Many factors determine whether a parasite can establish itself successfully in a host and initiate an infectious process. An important mechanism that a host can employ to combat disease and that can be studied, in vitro, at the cellular level is phagocytosis. The importance of this host-defense mechanism has been apparent since the process was first described by Metchnikoff in the latter part of the nineteenth century. However, the mechanism(s) involved in engulfment and destruction of ingested microorganisms have been the subject of much study and controversy. The early literature dealing with phagocytosis has been adequately reviewed (1,2). These scholarly works concentrate mainly on the physical forces involved with engulfment and also on the different factors that can effect the phagocytic act. Inexplicably little or no studies on the biochemical aspects of phagocytosis were carried out or reported in this early period. Some scattered reports, however, did appear (3). Somewhat later some excellent work was carried out in Nungester’s laboratory. Unfortunately, most of this work was published in thesis form only (4, 5). These workers all demonstrated that the phagocytic act was accompanied by biochemical changes; specifically, an increased respiratory activity. Suter and his co-workers in the early 1950’s initiated a series of studies concerned with the interaction of tubercle bacilli and guinea pig exudate cells. They described this interaction at the biochemical level (6–8).

This paper is number XXX in a series entitled“The role of the phagocyte in host-parasite interactions.”