Herpes simplex virus infection and damage in the central nervous system: immunomodulation with adjuvant, cyclophosphamide and cyclosporin A.

The role of the immune system in damage to the central nervous system (CNS) following infection with herpes simplex virus (HSV) was studied with the use of immune adjuvants and immunosuppressive drugs. The incidence of paralysis was found to be influenced significantly by the immune status of the animal. Thus, cyclosporin A (CsA) reduced the incidence of ear paralysis following inoculation of the pinna with virus, whilst cyclophosphamide (CY) increased the incidence of hind limb paralysis following i.v. inoculation with virus. Non-specific immunopotentiation with complete Freund's adjuvant (CFA) increased the incidence of hind limb paralysis. The inclusion of CNS antigen (mouse spinal cord homogenate) with the adjuvant enhanced the effect of adjuvant alone. The findings suggest that regulation of the immune response in the CNS may be of importance in the control of HSV-induced neuropathology.