Uptake and killing of Mima polymorpha and Herellea vaginicola by the reticuloendothelial system of neonatally thymectomized nonwasted mice.

Phagocytosis and killing of Mima polymorpha and Herellea vaginicola by the liver, lungs, spleen, and kidneys from neonatally thymectomized nonwasted mice and their sham-thymectomized litter mates were compared. The removal of M. polymorpha from blood by these organs, measured 2 and 4 hr after intravenous injection of bacteria, was not affected by thymectomy. Because significantly fewer viable organisms persisted in the liver, spleen, and kidneys, it is concluded that bacterial killing increased after thymectomy. Phagocytosis of M. polymorpha by peritoneal macrophages increased in thymectomized mice. Removal of H. vaginicola from the blood by the lungs was greater after thymectomy. Thymectomy did not affect the killing of H. vaginicola by the liver, spleen, lungs, or kidneys. Killing of H. vaginicola by the kidney was less than that by other organs, although this was not affected by thymectomy. Chronic reticuloendothelial stimulation associated with infection was not an adequate explanation for these findings because no wasting syndrome was encountered.