Neutrophil extracellular traps capture the human pathogen, Candida albicans, in blood and delay hyphal transformation

Abstract

In tissues, neutrophils neutralize Candida albicans through phagocytosis and delay C. albicans hyphae growth by deploying neutrophil extracellular traps (NETs). However, in the bloodstream, the dynamic interactions between NETs and C. albicans are far less understood. Here, we employ a microfluidic assay and measure a significant increase in intact NETs in blood within 3 h after adding C. albicans yeast or hyphae. We show that C. albicans yeast can be captured efficiently on NETs, thereby delaying the transition to hyphal growth. We measure higher amounts of intact NETs in blood samples from invasive candidiasis patients compared to healthy participants, both with and without stimulation. These findings suggest that both C. albicans yeast and hyphae in the bloodstream stimulate NET release, potentially aiding in their removal from the blood.

Keywords: candidemia; host-pathogen; innate immunity; microfluidic.