Abundant and Superficial Expression of C-Type Lectin Receptors in Ectocervix of Women at Risk of HIV Infection

Abstract

Dendritic cells (DCs) are among the first cells to encounter HIV after mucosal exposure and can bind virus via C-type lectin receptors (CLRs). Here, we characterized the distribution of various DC subtypes and the density of the CLRs, DC-SIGN, langerin, and mannose receptor in the ectocervix of HIV-seronegative women with low- and high-risk behavior for acquiring HIV. Cryosections from ectocervical biopsies, collected from sexually active low-risk healthy HIV immunoglobulin G-negative women (n = 10) and HIV immunoglobulin G-negative commercial sex workers (n = 8), were assessed by computerized image analysis. We identified various distinct DC populations. CD11c(-)CD1a(+)langerin(+) cells were localized in the epithelium, whereas CD11c(+)CD1a(-)DC-SIGN and CD11c(-)CD1a(-)CD68(+)DC-SIGN(+)mannose receptor(+) cells were restricted to the lamina propria of the ectocervix. CD123(+) cells were found at low incidence and did not express any of the investigated CLRs. The density of CLR expression was significantly higher in the high-risk as compared with the low-risk women. The superficial and abundant presence of potential HIV target cells makes the ectocervix a likely site for HIV transmission. The detected variations in density and localization of potential HIV receptors should be considered when developing topical prophylactic measures.