CD4 and HIV-1 infection: Our previous studies and those from other groups have identified multiple immune cell populations in these explant cervical (and penile) tissues including resident memory CD4 + T cells along with mDC populations derived that are 28% for CD1c positive, 12% CD207 (langerin) positive, and 7.69% CD209 (DC-SIGN) positive (Fig 2), which is in accordance with previous findings [24,73–75] Th1 and Th17 cells are abundant in both the blood and mucosa and are highly permissive to HIV-1 infection [76–79].