[Effect of ara-A on the experimental herpes simplex virus encephalitis--pathology and fluctuation of the cerebrospinal fluid and serum antibody levels].

The effect of Ara-A treatment on the experimentally induced herpes simplex virus (HSV) encephalitis in rabbits was examined. Simultaneously practical value of enzyme-linked immunosorbent assay (ELISA) for rapid diagnosis was tested to find an early rise of antibody in cerebrospinal fluid (CSF) and serum in connection with an adoption of Ara-A administration. HSV encephalitis was produced by inoculation with type-1 HSV into the bilateral corneas of the eyes. A large amount of pus and typical neurological signs characteristic to encephalitis appeared after several days of infection. Ara-A therapy begun at the 3rd day of infection clearly increased the survival rate (90%) and improved the clinical signs, but the start of the drug at the 6th day could only increase the survival rate (60%) without cure of the clinical symptoms. ELISA could catch the early rise of IgG antibody in CSF from 3-4 days and in serum from 4-6 days after infection. Ara-A didn't interfere the antibody production. Viral antigens were found in the corneal epithelia and propria, neurons and Schwann's cells of trigeminal ganglia, neurons and glial cells of pons and cerebrum, especially in hippocampal nuclei. Typical Cowdry A and full type intranuclear inclusion bodies in the neurons were observed in the above tissues with infiltration of large amount of small round cells. In conclusion, Ara-A therapy in HSV encephalitis at the early stage of infection was quite effective for cure and the ELISA method is a useful tool for detection of early antibody rise in CSF and serum.