FIG. 1.

Efficient knockdown of CCR5 by passenger-strand shortened siRNAs. (A) Sequences of the two sets of siRNA targeting CCR5 used in the experiments. Guide strands are colored black, and sense strands are gray. (B) GHOST-R5/X4 cells were transfected with 40 nM siRNAs, and total RNAs were extracted for RT-qPCR analysis of CCR5 mRNA expression at the indicated time points after transfection. (C) GHOST-R5/X4 cells were transfected as in (B) and were subjected to flow cytometric analysis at the indicated time points after transfection. (D) Forty-eight hours after transfection of 40 nM siRNA, GHOST-R5/X4 cells were infected with 2,000 TCID₅₀/ml HIV-1 JR-FL pseudovirus, and infectivity was determined by luciferase activity analysis. Data shown are the means of three independent experiments, and the error bars indicate the standard deviations. NC, negative control siRNA.