Envelope sequence and function of R5 SHIV
molecular clones. (A) Comparison of envelope gp160 sequence of SHIVSF162P3N clones 8 and 11. Dots denote identical residues in the sequence and * indicates potential N-linked glycosylation sites (PNGSs). PNGSs that are absent or re-positioned in clone 8 envelope gp120 are designated by black and red boxes, respectively. (B) Entry into TZM-bl cells and U87.CD4 indicator cell lines, and (C) sCD4 sensitivity and infection of primary macrophages that express low levels of CD4 with pseudotyped viruses bearing clone 8 and 11 Env gp160. Infectivity in macrophages was expressed as a ratio of infectivity in autologous PBMCs that express high levels of CD4 and CCR5. RLU, relative light unit. All viral entry and infectivity experiments were tested in triplicates. Data shown are the means and standard deviations from triplicate wells and are representative of at least two independent experiments.