Demyelination induced by the JHM virus in mice is directly caused by viral infection of white matter glial cells rather than an immune-mediated mechanism.
Demyelinative lesions were produced in mice by inoculation of JHM virus, a neurotropic strain of mouse hepatitis virus. The production of these lesions was dependent on dosage of virus, age of mice, and route of inoculation. In animals with demyelination, fluorescent antibody staining showed viral antigen was most prominent in the cells of the white matter. No immunopathologic mechanism for demyelination was apparent. No fixation of immunoglobulins in the lesions was seen, nor did immunosuppression with cyclophosphamide prevent demyelination. Focal hepatitis, usually a concomitant finding with white-matter disease, could be prevented without altering the demyelinative lesions. Demyelination in JHM virus-infected mice appeared to be the direct result of infection of glial cells of the white matter.
Leslie P. Weiner (Tue,) studied this question.