Reconstitution of Semliki forest virus infected mice, induces immune mediated pathological changes in the CNS.

Reconstitution of Semliki forest virus infected nude mice with spleen cells from their immunocompetent nu/+ litter mates resulted in an abolition of the otherwise persistent brain virus, production of anti-SFV IgG, and development of normally absent brain pathology. The brain pathological changes, including demyelination, seem to be mediated by T cells, and are maximum 14 days after sensitization of the reconstituting spleen cells. Sensitization of the spleen cells 7 days before transfer to the nude mice results in pathological changes advanced by about 8 days, compared to reconstitution with unsensitized cells. The involvement of T cells in the virus-induced pathology is discussed.