Tuesday 8 January 2008
Dendritic cells (DCs) are thought to mediate HIV-1 transmission but it is becoming evident that different DC subsets at the sites of infection have distinct roles.
In the genital tissues, two different DC subsets are present: the Langerhans cells (LCs) and the DC-SIGN(+)-DCs.
Although DC-SIGN(+)-DCs mediate HIV-1 transmission, recent data demonstrate that LCs prevent HIV-1 transmission by clearing invading HIV-1 particles.
However, this protective function of LCs is dependent on the function of the C-type lectin Langerin (CD207): blocking Langerin function by high virus concentrations enables HIV-1 transmission by LCs.
de Witte L, Nabatov A, Geijtenbeek TB. Distinct roles for DC-SIGN(+)-dendritic cells and Langerhans cells in HIV-1 transmission. Trends Mol Med. 2007 Dec 3; PMID: #18055263#