Selected mutants of mouse hepatitis virus type 4 (JHM strain) induce different CNS diseases. Pathobiology of disease induced by wild type and mutants ts8 and ts15 in BALB/c and SJL/J mice.
The model system of central nervous system (CNS) disease induced by mouse hepatitis virus type 4 (MHV-4) is explored by comparison of wild type (wt) MHV-4 and two temperature-sensitive (ts) mutants, designated ts8 and ts15, in BALB/c and SJL/J mice. In BALB/c mice, 3 plaque-forming units (PFU) of wt MHV-4 given intracerebrally caused fatal encephalomyelitis in all mice by 7 days after infection, with spread of virus outside the CNS, especially to liver. In SJL/J mice, 3 PFU of wt virus was cleared within 2-3 days, with little spread, and up tp 100 PFU failed to cause fatal encephalomyelitis. However, larger amounts of virus, like 1000 PFU, caused fatal encephalomyelitis in SJL/J mice. In contrast, 10(4) PFU of MHV-4 ts8 did not cause death in either BALB/c or SJL/J mice, and persisted in the CNS of both strains while retaining its ts phenotype. There was significatnly less spread of virus outside the CNS. BALB/c mice usually showed demyelination, remyelination, and recurrent demyelination with ts8, while SJL/J mice only rarely had lesions. Intracerebral inoculation with 10(4) PFU of MHV-4 ts15 was associated with a persistent infection in CNS and liver of BALB/c mice; however, only occasional demyelination and hepatic lesions occurred. TS15 did not cause death in either BALB/c or SJL/J mice and did not cause histopathologic injury in SJL/J mice.
D000818:Animals; D000956:Antigens, Viral / Q000276:immunology; D002490:Central Nervous System / Q000276:immunology; D002493:Central Nervous System Diseases / Q000382:microbiology*; D003711:Demyelinating Diseases / Q000382:microbiology; D004660:Encephalitis / Q000382:microbiology; D008099:Liver / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D008815:Mice, Inbred Strains; D006517:Murine hepatitis virus / Q000235:genetics* / Q000276:immunology / Q000472:pathogenicity; D009132:Muscles / Q000276:immunology; D009154:Mutation; D009836:Oligodendroglia / Q000276:immunology; D013154:Spleen / Q000276:immunology; D013950:Thymus Gland / Q000276:immunology
D000956:Antigens, Viral