Inhibition of virus-induced age-dependent poliomyelitis by interferon-gamma.

Age-dependent poliomyelitis (ADPM) is a neuroparolytic disease which results from combined infection of susceptible mice with lactate dehydrogenase-elevating virus (LDV) and murine leukemia virus (MuLV). The present study examined the effects of interferon-gamma (IFN-gamma) treatment on the incidence of ADPM, replication of LDV and MuLV and anti-LDV immunity. IFN-gamma treatment of ADPM-susceptible C58/M mice protected them from paralytic disease, but had no detectable effect on the IgG anti-LDV response or LDV viremia. IFN-gamma-mediated protection from ADPM correlated with reduced expression of LDV RNA, but not MuLV RNA, in the spinal cords of C58/M mice. These results confirm that spinal cord LDV replication is the determinant of ADPM and demonstrate that cytokine-mediated inhibition of LDV replication in the central nervous system prevents neuroparalytic disease.