“…Less information is available for the male system, but IgA-secreting plasma cells and pIgR-expressing epithelial cells occur in the urethral glands of Littré, epididymis, prostate, and seminal vesicles of humans (1,37,39) and mice (36). The secretions of both male and female systems contain significant levels of SIgA, but these may be exceeded by IgG levels, at least in humans and other primates (3,4,6,9,18,26,27). Whereas SIgA is accepted as the distinct product of the CMIS, the source and means of delivery of IgG are less clear: both local production and transudation from the circulation have been implicated (reviewed in references 2 and 23).…”