Macrophages and resistance to JHM virus CNS infection.

Thioglycollate elicited peritoneal exudate cells from resistant SJL mice, younger susceptible SJL mice, and susceptible ASW, BALB/c, and C57/BL6 mice all exhibit extrinsic antiviral activity. The active cell was characterized as a Thy 1.2 negative, Ia negative, radiation resistant adherent cell. The antiviral activity was not due to nonspecific cellular cytotoxicity directed against the susceptible cell nor interferon. Adherent PE cells from resistant and susceptible SJL mice were similar with respect to the number of phagocytes, nonspecific esterase containing, Fc, and C3b receptor bearing cells. Finally, extrinsic antiviral activity was not dependent upon intrinsic antiviral activity.