FIG. 3.

Coreceptor usage by primary HIV-1 isolates. Cf2-Luc cells were transfected with pcDNA3-CD4 alone or cotransfected with pcDNA3-CD4 and pcDNA3 expressing CCR2b, CCR3, CCR5, CCR8, CXCR4, CX3CR1, Gpr1, Gpr15, Strl33, or Apj and infected with equivalent amounts of each HIV-1 isolate as described in Materials and Methods. Viruses were isolated from brain (br), CSF, PBMC, lymph node (LN), spleen (spln), and spinal cord (SC) by coculture with CD8-depleted PBMC. Cell lysates were prepared at 48 h postinfection and assayed for luciferase activity. Data are expressed as means from duplicate infections. Error bars represent standard deviations. Similar results were obtained in two independent experiments.