Innate immunity including epithelial and nonspecific host factors: workshop 1B.

The majority of HIV infections are initiated at mucosal sites. The oral mucosal tissue has been shown to be a potential route of entry in humans and primates. Whereas HIV RNA, proviral DNA, and infected cells are detected in the oral mucosa and saliva of infected individuals, it appears that the oral mucosa is not permissive for efficient HIV replication and therefore may differ in susceptibility to infection when compared to other mucosal sites. Since there is no definitive information regarding the fate of the HIV virion in mucosal epithelium, there is a pressing need to understand what occurs when the virus is in contact with this tissue, what mechanisms are in play to determine the outcome, and to what degree the mechanisms and outcomes differ between mucosal sites. Workshop 1B tackled 5 important questions to define current knowledge about epithelial cell-derived innate immune agents, commensal and endogenous pathogens, and epithelial cells and cells of the adaptive immune system and how they contribute to dissemination or resistance to HIV infection. Discovering factors that explain the differential susceptibility and resistance to HIV infection in mucosal sites will allow for the identification and development of novel protective strategies.