THE ROLE OF CELL WALL CARBOHYDRATES IN BINDING OF MICROORGANISMS TO MOUSE PERITONEAL EXUDATE MACROPHAGES

Abstract

The recognition by macrophages of unopsonized bacteria was studied, employing a binding assay, performed at 4.degree. C. Various gram positive and gram negative bacteria were shown to bind to glass-adherent mouse peritoneal exudate cells under these conditions, Streptococcus pneumoniae being the only exception. The binding could be inhibited by pretreatment of the macrophage monolayers with various monosaccharides. The role of particular components of the bacterial cell wall in binding was examined further using different strains of Klebsiella aerogenes and Salmonella typhimurium with a known cell composition and mutant strains deficient in certain sugars. The ability of a particular constituent to inhibit binding was found to correlate closely with its presence in the bacterial cell wall. This form of binding, mediated by cell wall carbohydrates may represent a primitive recognition mechanism enabling phagocytes to bind microorganisms.