A SIMPLE METHOD TO DISTINGUISH BETWEEN SIMIAN IMMUNODEFICIENCY VIRUS ISOLATES BY RESTRICTION ANALYSIS OF PCR PRODUCTS

A simple method to distinguish between simian immunodeficiency virus ( SIV) isolates of experimentally infected rhesus macaques is reported. Peripheral blood mononuclear cells (PBMC) were prepared from a rhesus macaque infected with SIV(StM) isolated originally from a stump-tailed macaque, or from a rhesus monkey infected with SIV(SM) from a sooty m angabey monkey. PBMC were cocultivated with CEM x 174 cells and a regi on of the SIV envelope (env) gene was amplified by the polymerase chai n reaction (PCR) from cDNA of infected cocultivation cells. Restrictio n enzyme digestion analysis of the PCR products enabled SIV(StM) and S IV(SM) to be differentiated from each other, and from a molecular clon e of SIV(MAC), SIV(MAC)239, originally isolated from an infected rhesu s macaque. Furthermore, when SIV(SM) and SIV(StM) were introduced into the same animal, restriction enzyme analysis of the PCR product ampli fied from cocultivation cells of this rhesus macaque suggested that th e animal was superinfected.