Oropharyngeal candidiasis (OPC) is an AIDS-defining illness, caused mainly by the commensal fungus Candida albicans (C.albicans). C. albicans plays a major role in causing infections in seriously ill, immunocompromised individuals, cancer patients, and patients undergoing steroid and irradiation treatments. Oral C. albicans also causes complications in patients wearing dentures. C. albicans causes infections of the mucosal, nail or skin surfaces, termed as chronic mucocutaneous candidiasis (CMC), which is frequent in patients with certain genetic pre-dispositions. Importantly, it is the fourth most common pathogen found in hospitalized patients, and with an alarming increase in biofilm infections associated with medical devices and anti-fungal drug resistance, there is a pressed need to develop immunotherapeutics. OPC infection, like other fungal and extracellular bacterial infections, is controlled by innate immunity, and the recently discovered IL-17 producing CD4 T cells called Th17 cells. We hope to harness the mechanism of Treg function for treating mucosal dysfunction and inflammation. This study will also lead to potential novel targets to increase Treg functions and treat OPC infections and CMC, by oral cellular immunotherapy and oral vaccination.