APPLICATION OF POLYMERASE CHAIN-REACTION FOR THE DIAGNOSIS OF CAPRINEARTHRITIS-ENCEPHALITIS

A study was performed to determine whether goats naturally infected wi th caprine arthritis-encephalitis virus (CAEV) could be detected by th e use of polymerase chain reaction (PCR) amplification of genomic DNA. The PCR primers were designed to amplify a 433 base pair region of th e proviral gag gene. Adherent cells from peripheral blood mononuclear cells (PBMC) were subjected to amplification employing the hot start m ethod using paraffin wax and silicon oil as a reaction mix overlay. Th e most reliable results were obtained when DNA extracted from adherent cells from PBMC culture was used as target DNA in the PCR reaction. W ith this PCR procedure it was possible to detect CAEV proviral DNA in 100 ng of genomic DNA from infected goat synovial membrane (GSM) cells when agarose gel electrophoresis followed by ethidium bromide stainin g was used. Using hybridization analysis the sensitivity of the assay was increased to 100 pg of genomic DNA. Although more sensitive serolo gic assays must be developed for screening purposes, PCR used in combi nation with hybridization analysis will provide a sensitive diagnostic assay to detect CAEV when no antibody response is present and CAEV in fection is suspected.