Emerging Fungal Pathogen Candida auris Evades Neutrophil Attack

Candida auris has recently emerged as the first fungal pathogen to cause a global public health threat. The reason this species is causing hospital-associated outbreaks of invasive candidiasis with high mortality is unknown. In this study, we examine the interaction of C. auris with neutrophils, leukocytes critical for control of invasive fungal infections. We show that human neutrophils do not effectively kill C. auris. Compared to Candida albicans, neutrophils poorly recruited to C. auris and failed to form neutrophil extracellular traps (NETs), which are structures of DNA, histones, and proteins with antimicrobial activity. In mixed cultures, neutrophils preferentially engaged and killed C. albicans over C. auris. Imaging of neutrophils in a zebrafish larval model of invasive candidiasis revealed the recruitment of approximately 50% fewer neutrophils in response to C. auris compared to C. albicans. Upon encounter with C. albicans in the zebrafish hindbrain, neutrophils produced clouds of histones, suggesting the formation of NETs. These structures were not observed in C. auris infection. Evasion of neutrophil attack and innate immunity offers an explanation for the virulence of this pathogen.