CCR5 and HIV-1 infection: Additional western blot experiments confirmed our protein microarray results and showed that HIV-1 infection increased phosphorylation of Rac1 at S71, and phosphorylation of ERK1/2 in human monocytes following monocyte-endothelial communication, and the CCR5 antagonists maraviroc and TAK-779 diminished HIV-induced phosphorylation of Rac1 and ERK1/2 (Figure 4E).