Innate and acquired immunity in the human penile urethra.

In men, the penile urethra is a primary infection site for sexually transmitted pathogens. Research on the immunology of this mucosal site has been limited in part due to sampling challenges, but available evidence indicates that the urethra contains a rich contingent of immunological mediators that can mount vigorous innate and adaptive immune responses against infectious organisms. Further research is needed to define approaches to stimulate immunity at this mucosal site to prevent the transmission of HIV-1 and other sexually transmitted pathogens.