Differences in the Tropism and Nitric Oxide Production by Goat Brain Cells Infected with Caprine Arthritis Encephalitis Virus

Different types of brain cells prepared from goat-kid cerebrum explant cultures were infected by direct application of Caprine Arthritis Encephalitis Virus (CAEV). Predominantly, cells of the monocyte-macrophage lineage were specifically infected by the virus as proviral DNA was detected in infected cultures by amplification of a 414 base-pair (bp) fragment of the viral gag-gene by Reverse Transcription-Polymerase Chain Reaction (RT-PCR). Nitric oxide (NO) production by infected brain cells under different treatment groups was quantified by photometric methods. Infected enriched microglia cells produced more NO than any other group of cells cultured from the goat brain cerebrum. The present study shows that microglia are targets cells infected by the CAE virus in the brain of goats. It is believed that this finding will assist in devising immuno-prophylactic and immuno-therapeutic measures to be adopted in the management of neurological dysfunctions resulting from retroviral infections. It is also possible that the present observation on the tropism of the virus with the attendant NO production may have important implications in the pathogenesis of retroviral and other viral infections of man and animals. Key Words: CAEV, RT-PCR, gag gene, microglia cells. Trop. Vet. Vol. 21: (3) 200-206 (2003)