The Th17/IL-17 Axis and Host Defense Against Fungal Infections

Chronic mucocutaneous candidiasis (CMC) was recognized as a primary immunodeficiency in the early 1970s. However, for almost 40 years, its genetic etiology remained unknown. The progressive molecular and cellular description of inborn errors of immunity (IEI) with syndromic CMC pointed toward a possible role of IL-17-mediated immunity in protecting against fungal infection and CMC. Since 2011, novel IEI affecting either the response to or production of IL-17A and/or IL-17F (IL-17A/F) in patients with isolated or syndromic CMC provided formal proof of the pivotal role of the IL-17 axis in mucocutaneous immunity to Candida spp, and, to a lesser extent, to Staphylococcus aureus in humans. In contrast, IL-17-mediated immunity seems largely redundant against other common microbes in humans. In this review, we outline the current knowledge of IEI associated with impaired IL-17A/F-mediated immunity, highlighting our current understanding of the role of IL-17A/F in human immunity. & COPY; 2023 American Academy of Allergy, Asthma & Immunology

Automated summary

Chronic mucocutaneous candidiasis (CMC) is recognized as a primary immunodeficiency, and recent studies have identified the genetic etiology of CMC linked to impaired IL-17-mediated immunity. The IL-17 axis plays a crucial role in mucocutaneous immunity to Candida spp and Staphylococcus aureus in humans, while it seems to be redundant against other common microbes. This review provides an overview of the current understanding of IL-17A/F-mediated immunity and its relevance in human immunity.