Quantification of proviral DNA load of human immunodeficiency virus type 2 subtypes A and B using real-time PCR

HIV-2 infection is confined mostly to West Africa. Seven HIV-2 subtypes have so far been described; only HIV-2 subtypes A and B are prevalent, the others being considered self-limiting infections at the epidemiological level. The main limitation for the HIV-2 DNA proviral quantification is the lack of HIV-2 DNA standard. We designed and tested a new HIV-2 primer couple that amplifies both the HIV-2 ROD strain and HIV-1 LAV/BRU strain. These HIV-2 primers were used to quantified an HIV-2 standard comparatively to a standard widely used in proviral DNA HIV-1 quantification, i.e., the 8E5 cell line transfected by a single defective integrated provirus of HIV-1 BRU/LAV by cell. The primers and probe used to quantify HIV-2 DNA are located in a long terminal repeat (LTR) region with low variability. These primers amplify both HIV-2 subtypes A and B. The relevance of the follow-up of the infected patients by the quantification of the proviral DNA HIV-2 is currently studied.