Immunofluorescent Studies of the Histopathogenesis of Lymphocytic Choriomeningitis Virus Infection

Abstract

The pathogenesis of lymphocytic choriomeningitis (LCM) virus infection of mice has been subjected to intensive study by virus titration and histopathologic techniques (1-5). There are a number of unresolved questions relating to the pathogenesis of the various types of infection which require study of the distribution of virus at the cellular, rather than at the whole organ level. This report describes a direct immunofluorescent antibody test for LCM antigen, and its application to study of cellular distribution of infection in acutely and congenitally infected mice. Materials and MethodsMice.--Weanling mice of the HA/ICR strain were purchased from Charles River Mouse Farms, Brookline, Massachusetts. Latent LCM infection was not detected in these mice.LCM Virus.--The CA 1371 (mouse brain-passaged) and WCP (viscerotropic) strains of LCM virus, and the procedures for preparation of virus stocks have been described previously (6). Swiss mice congenitally infected with LCM virus were from the colony of carrier mice initiated by Haas (7); these mice were in approximately the 41st generation as carriers.Virus Titrations.--Virus suspensions (clarified by centrifugation at 1800 Rmt for 10 minutes) and serial 10-fold dilutions were made in medium 199 with 3 per cent inactivated calf serum. Materials were held in an ice bath, and inoculations made as soon as possible after preparation of suspensions. Weanling mice were inoculated intracerebrally with 0.03 ml, using 6 mice per dilution. Survivors were rechallenged at 14 days postinoculation with approximately 1000 LD60 of strain CA 1371 LCM virus, and held an additional 14 days. In. fectivity titers, based on typical death or immunity to challenge as the endpoint, were calculated according to the method of Reed and Muench, and are expressed as the logt0 of the number of IDs0 per 0.03 mi of 10 per cent suspension. Because of the high degree of pathogenicity of the CA 1371 strain following intracerebral inoculation, immunity tests were not considered necessary to evaluate infectivity titration endpoints with this strain.Tissue Cultures.--Primary cultures of trypsinized kidney ceils of monkey (rhesus and Cercopitkecus), rabbit, and Syrian hamster were used, as well as WI-26 cells and primary cultures of HA/ICR mouse embryo. All cells were grown on 9 x 35 mm coverslips in Leighton tubes. 829

Effects of Promyelocytic Leukemia Protein on Virus-Host Balance

“…Cytotoxic CD8 ϩ T-cell-mediated hepatitis in mice caused by infection with the hepatotropic LCMV-WE (35,37,46,71) correlates with elevated levels of ALT in the serum (75). To determine whether PML influenced this immunopathologic disease, which depends on critical parameters of virus-host balance such as infectious dose and immune competence of the host (75), PML Ϫ/Ϫ and control mice were infected i.v.…”

Immune conflicts in lymphocytic choriomeningitis virus

“…Histologically, there is marked inflammation of the choroid plexus, ependyma, and leptomeninges characterized by destructive lesions and a predominately lymphocytic infiltrate [41,68]. Two general observations provided evidence that acute choriomeningitis was an immunologically mediated disease.…”

Lymphocytic Choriomeningitis, Mouse

“…In the wild, infection is passed vertically from mother to offspring in utero or, less likely, by naso-oral infection after contact with nasal secretions and/or excreta from infected mice (Traub 1936b(Traub , 1939. The distribution of viral antigen and lack of microscopic lesions in animals infected in utero are indistinguishable from animals experimentally infected neonatally (Wilsnack and Rowe 1964) .…”