In vitro Interaction of Scrapie Agent and Mouse Peritoneal Macrophages

Abstract

Scrapie brain homogenate was mixed with mouse peritoneal macrophages in vitro. After 2 h of incubation at 37°, a portion of the scrapie infectivity was associated with macrophages. In contrast, very little infectivity was associated with kidney cells that had been exposed to scrapie brain homogenate. After incubation of the scrapie brain homogenate-macrophage mixture at 4° rather than 37°, a reduced quantity of infectivity was associated with the macrophages. These results show that after in vitro incubation, the scrapie agent was associated with macrophages, and the data suggest that phagocytic activity was involved.