A genome-scale screen identifies sulfated glycosaminoglycans as pivotal in epithelial cell damage by Candida albicans

Candidalysin is a cytolytic peptide produced by the opportunistic fungal pathogen Candida albicans. This peptide is a key virulence factor in mouse models of mucosal and hematogenously disseminated candidiasis. In this study, we performed a genome-wide loss-of-function CRISPR screen in a human oral epithelial cell line TR146 to identify specific host factors required for susceptibility to candidalysin-induced cellular damage. We first generated a TR146 cell line that stably expressed Cas9, and then transduced this cell line with a lentiviral sgRNA library (Brunello) that has four sgRNAs for each of 19,114 human genes. The transduced cells were incubated with 30micromolar candidalysin for 8 h, which resulted in 60-70% cell death in control TR146 cells, as measured by an XTT assay. After five rounds of selection with a recovery step in between each round, the genes targeted by sgRNAs in the surviving cells were identified via next-generation sequencing and the frequency of each sgRNA was compared with that in the initial library.