The Role of Human IL-17 Immunity in Fungal Disease

Candida species are major causes of invasive and mucocutaneous fungal infections. Various recognition pathways and effector mechanisms are involved in triggering intrinsic, innate and adaptive host immune responses to these fungi. Invasive candidiasis may involve almost any internal organ or anatomic site and is a significant cause of morbidity and mortality in immunocompromised individuals, including, in particular, those with primary immunodeficiency disorders (PIDs) affecting phagocytic cells. Other PIDs characterized by an impairment of IL-17 T cell-mediated immunity confer predisposition to mucocutaneous Candida infections, with Candida albicans in particular. We discuss here inborn errors of immunity leading to an impairment of IL-17-mediated host defense and the occurrence of mucocutaneous candidiasis.