SIVcpz from a naturally infected Cameroonian chimpanzee: Biological and genetic comparison with HIV-1N

Thus far, simian immunodeficiency virus from chimpanzees (SIVcpz) genomes h ave been characterized as Pan troglodytes troglodytes and show a strong rel ation with human immunodeficiency virus (HIV)-1 N in their env genes. We fu lly characterized another SIVcpz from P. t. troglodytes. This chimpanzee (C am5) was, as was also the host of SIVcpz-cam3, wild born in Cameroon, a reg ion where all three groups of HIV-I (M, N and O) co-occur. In contrast to o ther SIVcpz, SIVcpz-cam5 was isolated immediately after the rescue of the a nimal. Our data demonstrate that SIVcpz-cam5, like SIVcpz-cam3, grows easil y on human peripheral blood mononuclear cells (PBMCs) and uses CCR5 as a co -receptor similar to HIV-1 N YBF30. Phylogenetic analysis based on the enti re env gene shows that SIVcpz-cam5 falls into the same unique subcluster as HIV-1 N YBF30, SIVcpz-cam3 and SIVcpz-US. A phylogenetic relationship was also found with the vif gene of HIV-1 N. This study provides proof that HIV -1 N related viruses circulate in wild P. t. troglodytes.