Functional genomics identifies type I interferon pathway as central for host defense against Candida albicans

Candida albicans is the most common human fungal pathogen causing mucosal and systemic infections. However, human antifungal immunity remains poorly defined. Here by integrating transcriptional analysis and functional genomics, we identified Candida -specific host defence mechanisms in humans. Candida induced significant expression of genes from the type I interferon pathway in human peripheral blood mononuclear cells. This unexpectedly prominent role of type I interferon pathway in anti- Candida host defence was supported by additional evidence. Polymorphisms in type I interferon genes modulated Candida -induced cytokine production and were correlated with susceptibility to systemic candidiasis. In in vitro experiments, type I interferons skewed Candida -induced inflammation from a Th17 response towards a Th1 response. Patients with chronic mucocutaneous candidiasis displayed defective expression of genes in the type I interferon pathway. These findings indicate that the type I interferon pathway is a main signature of Candida -induced inflammation and has a crucial role in anti- Candida host defence in humans. Systemic infection with the fungal pathogen C. albicans is characterized by high mortality, and the precise antifungal defence mechanisms in humans are poorly defined. Using a systems approach, Smeekens et al . describe a previously unknown role for type I interferons in human anti- Candida defence.