Oral immunization of mice against candidiasis.

Oral immunization with live Candida albicans evoked antibody- and cell-mediated immune responses in gnotobiotic C.B-17 and BALB/c mice. No deaths or systemic candidiasis of endogenous origin were evident in these C. albicans-colonized (pure culture) mice. Histologic examination showed minimal to no infection of the stomach, esophagus, or tongue by C. albicans. Not only were orally immunized mice more resistant to systemic candidiasis (intravenous challenge) than were germfree (nonimmunized) controls, but immunity could be transferred to susceptible mice with immune spleen cells. Oral immunization elicited a Th1-type response in spleen cells and a Th2 response in Peyer's patch lymphocytes. The alimentary tracts of these orally immunized mice remained chronically colonized with C. albicans in spite of the presence of both antibody- and cell-mediated immune responses to C. albicans.