title: Opportunistic pathogen Candida albicans elicits a temporal response in primary human mast cells.
abstract: Immunosuppressed patients are frequently afflicted with severe mycoses caused by opportunistic fungal pathogens. Besides being a commensal, colonizing predominantly skin and mucosal surfaces, Candida albicans is the most common human fungal pathogen. Mast cells are present in tissues prone to fungal colonization being expectedly among the first immune cells to get into contact with C. albicans. However, mast cell-fungus interaction remains a neglected area of study. Here we show that human mast cells mounted specific responses towards C. albicans. Collectively, mast cell responses included the launch of initial, intermediate and late phase components determined by the secretion of granular proteins and cytokines. Initially mast cells reduced fungal viability and occasionally internalized yeasts. C. albicans could evade ingestion by intracellular growth leading to cellular death. Furthermore, secreted factors in the supernatants of infected cells recruited neutrophils, but not monocytes. Late stages were marked by the release of cytokines that are known to be anti-inflammatory suggesting a modulation of initial responses. C. albicans-infected mast cells formed extracellular DNA traps, which ensnared but did not kill the fungus. Our results suggest that mast cells serve as tissue sentinels modulating antifungal immune responses during C. albicans infection. Consequently, these findings open new doors for understanding fungal pathogenicity.
authors.affiliation: 1] Department of Clinical Microbiology, Umeå University, Umeå, Sweden [2] Umeå Centre for Microbial Research (UCMR), Umeå, Sweden [3] The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå, Sweden.
authors.forename: José Pedro
authors.initials: JP
authors.lastname: Lopes
authors.affiliation: 1] Department of Clinical Microbiology, Umeå University, Umeå, Sweden [2] Umeå Centre for Microbial Research (UCMR), Umeå, Sweden [3] The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå, Sweden.
authors.forename: Marios
authors.initials: M
authors.lastname: Stylianou
authors.affiliation: Department of Medicine, Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Gunnar
authors.initials: G
authors.lastname: Nilsson
authors.affiliation: 1] Department of Clinical Microbiology, Umeå University, Umeå, Sweden [2] Umeå Centre for Microbial Research (UCMR), Umeå, Sweden [3] The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå, Sweden.
authors.forename: Constantin F
authors.initials: CF
authors.lastname: Urban
mesh_terms: D000935:Antifungal Agents / Q000494:pharmacology; D002176:Candida albicans / Q000187:drug effects / Q000502:physiology*; D002177:Candidiasis / Q000382:microbiology / Q000473:pathology; D016923:Cell Death / Q000187:drug effects; D015550:Cell Degranulation / Q000187:drug effects; D002478:Cells, Cultured; D002630:Chemotactic Factors / Q000494:pharmacology; D016207:Cytokines / Q000378:metabolism; D004705:Endocytosis / Q000187:drug effects; D065206:Extracellular Traps / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D008407:Mast Cells / Q000187:drug effects / Q000382:microbiology*; D050296:Microbial Viability / Q000187:drug effects; D009000:Monocytes / Q000187:drug effects / Q000378:metabolism; D009504:Neutrophils / Q000187:drug effects / Q000378:metabolism; D013997:Time Factors
chemical_list: D000935:Antifungal Agents; D002630:Chemotactic Factors; D016207:Cytokines