New perspectives on the immunology of chronic mucocutaneous candidiasis

Chronic mucocutaneous candidiasis is a primary immune deficiency presenting as an inability to clear fungal infections and consequently as persisting and recurring infections of the skin and mucous membranes with yeasts, mostly Candida albicans. Chronic mucocutaneous candidiasis is a heterogeneous clinical syndrome which usually presents in childhood and can have an autosomal recessive, dominant or sporadic mode of inheritance. Most chronic mucocutaneous candidiasis patients also develop accompanying endocrine and inflammatory disorders that suggest an underlying deregulation of the immune system. It has long been recognized that protection from mucocutaneous candidiasis relies on cell-mediated immunity and studies on animal models have highlighted the essential role of type 1 cytokines in protection against Candida spp. Recent data in patients with chronic mucocutaneous candidiasis have documented altered patterns of cytokine production in response to Candida spp. with decreased production of some but not all type 1 cytokines and increased levels of interleukin-10. The defect underlying altered cytokine production remains unknown but studies are in progress addressing the putative role of dendritic cells and pattern recognition receptors in directing cytokine responses. These novel insights into immune mechanisms responsible for protection against Candida spp. are opening new possibilities of immunomodulation and vaccination that could prove beneficial in the management of chronic mucocutaneous candidiasis.