Differential Regulation of Myeloid-Derived Suppressor Cells by Candida Species

Abstract

Myeloid-derived suppressor cells (MDSCs) are innate immune cells characterized by their ability to suppress T-cell responses. Recently, we demonstrated that the human-pathogenic fungi <i>Candida albicans</i> and <i>Aspergillus fumigatus</i> induced a distinct subset of neutrophilic MDSCs. To dissect <i>Candida</i>-mediated MDSC induction in more depth, we studied the relative efficacy of different pathogenic non-<i>albicans Candida</i> species to induce and functionally modulate neutrophilic MDSCs, including <i>C. glabrata, C. parapsilosis, C. dubliniensis</i>, and <i>C. krusei</i>. Our data demonstrate that the extent of MDSC generation is largely dependent on the <i>Candida</i> species with MDSCs induced by <i>C. krusei</i> and <i>C. glabrata</i> showing a higher suppressive activity compared to MDSCs induced by <i>C. albicans.</i> In summary, these studies show that fungal MDSC induction is differentially regulated at the species level and differentially affects effector T-cell responses.