Abstract
Inbred female C3H mice were given, by intraperitoneal injection, 4 X 10(7) virulent Salmonella typhimurium organisms opsonised with specific antiserum. Peritoneal washings were obtained between 1.5 and 24 h after injection and examined by electronmicroscopy. Opsonised salmonellae were ingested rapidly by peritoneal exudate cells and were digested rapidly. The presence of antibody facilitated the phagocytic efficiency of the host cells. Destruction of ingested bacteria appeared to be an innate capacity of the host phagocytes independent of the presence of antibody.