In this study, we examined the effects of HIV infection on the transmigration of CD14+CD16+ monocytes across the BBB, demonstrated that heightened sensitivity to CCL2 and increased CCR2 are a mechanism by which HIV infected cells enter the CNS, and identified cell surface markers specific to this mature monocyte subpopulation which facilitate their diapedesis. The gene discussed is CCL2; the disease is HIV infectious disease.