(A) VSV-G envelope and HIV-1 envelope protein pseudotyped viruses are equally restricted by human TRIM5α. Titration of HIV-1[VSV-G], HIV-1[NL4.3] and HIV-1[BaL] viruses onto TZM-LNCX2 cells (closed symbols) and TZM cells expressing human TRIM5α(open symbols) result in 15.3 fold, 12.6 fold and 12.7 fold restriction to infection. (B) VSV-G pseudotyped Lv2-sensitive and Lv2-insensitive HIV-2 viruses are restricted by human TRIM5α. HIV-2[VSV-G] and HIV-2/I73V[VSV-G] viruses were used to infect TZM-LNCX2 cells (closed symbols) and TZM-huTRIM5α cells (open symbols). Human TRIM5α restricted VSV-G mediated HIV-2 infection 3.6 fold and 4.8 fold, respectively. (C) HIV-2 envelope pseudotyped HIV-2 particles reveal entry route dependent Lv2-mediated restriction. HIV-2[Env42S] and HIV-2/I73V[Env42] viruses were used to infect TZM-LNCX2 cells (closed symbols) and TZM-huTRIM5αcells (open symbols). The capsid mutation at position 73 (I73V) confers escape from Lv2-mediated restriction on TZM-LNCX2 cells (9.3 fold increase in infection), whereas the over expression of human TRIM5α in TZM-huTRIM5α cells results in a maximal restriction for both virus variants. Representative results from three independent experiments done in triplicate are shown. All virus preparations were titrated on the parental cell line TZM-bl. Error bars indicate the standard deviations of the data.