FIG. 7.

mRNA expression of HIV and SIV receptors and coreceptors in primary cell types. RT-PCR was used to test for chemokine receptor mRNA expression. (A) Amplification of GAPDH served as a control for intact mRNA. (B) The presence of chemokine receptor mRNA in Δ32/Δ32 CCR5 PBMCs and macrophages, astrocytes, and BMVECs was determined, with mRNA from coreceptor-expressing cell lines NP2/CD4 (CCR5, CXCR4, CCR3, CCR8, and GPR1) and GHOST (CXCR6 and GPR15) acting as positive controls. NP2/CD4 cells naturally expressed RDC1. The primers used are shown in Table 2. Lanes MWM, 100-bp molecular size DNA ladder. Each experiment was carried out with negative (water) (lanes −) and positive (mRNA from cells expressing the specific receptor) (lanes +) controls, as well as with the parental NP2/CD4 cells as a cellular negative control. The absence of contaminating genomic DNA was confirmed by carrying out all RT-PCRs on untranscribed mRNA (data not shown).