Abstract
Phagocytosis of monosaccharide-binding latex particles by guinea-pig polymorphonuclear leucocytes (PMNs) was investigated. When neuraminic acid or glucuronic acid was chemically bound to the surface of latex particles the degree of phagocytosis was somewhat lower than that for bare, glucose-, mannose- or rhamnose-binding latex particles. These experimental findings were interpreted in terms of the kind of monosaccharide and the surface potential and surface hydrophobicity of latex particles. As a result, it was concluded that the inhibitory action of neuraminic acid or glucuronic acid on phagocytosis arises from an increase in the surface hydrophilicity of latex particles brought about by the hydroxyl groups and negative charges on the chemically bound neuraminic acid or glucuronic acid molecules. Physically adsorbed glucuronic acid molecules were also found to decrease the degree of phagocytosis of latex particles by PMNs, though not so remarkable as the chemically bound monosaccharide molecules.