Use of polymerase chain reaction for diagnosis of type D simian retrovirus infection in macaque blood.

We developed a simple and specific polymerase chain reaction (PCR) method for the detection of type D simian retrovirus (SRV) infection (SRV-1, SRV-2, and SRV-3) using whole blood samples from macaques. Each pair of primers for the three serotypes of SRV was highly specific for its respective envelope proviral DNA and was sensitive enough to easily detect about five copies of the SRV-2 proviral genome. The PCR products were confirmed by Southern blot hybridization with digoxigenin-labeled internal oligonucleotide probes. For diagnostic purposes the three sets of primers were mixed together. The molecular weight of the PCR product for each of the three serotypes differed. Serotypes were confirmed by hybridization with a mixture of SRV-2 and SRV-1 and -3 internal probes. The PCR analysis of 39 whole blood samples correctly identified five SRV-1 and nine SRV-2 culture-positive samples. It also detected SRV-2 in two culture-negative blood samples from monkeys from which SRV had been previously isolated.