SPLENIC REGULATION OF CELL-MEDIATED-IMMUNITY TO LISTERIA-MONOCYTOGENES

Abstract

Splenectomized mice are more resistant than normal mice to infection by L. monocytogenes. The nature of splenic regulation of cell mediated immunity to Listeria was investigated. Splenectomized mice were reconstituted with normal syngeneic spleen cells and normal plasma from Listeria-stimulated normal donors to determine if suppression of resistance in normal mice was cellular or humoral. Mice receiving spleen cells showed no decreased resistance, but mice receiving plasma showed decreased resistance as determined from bacterial numbers in the liver. The suppressive effect was associated with plasma components having a MW of < 10,000. A suppressor factor may be produced by spleen associated cells in response to stimulation of the cell-mediated immune system.