Characterization of Virulence Factors in Candida Species Causing Candidemia in a Tertiary Care Hospital in Bangkok, Thailand

Abstract

Candidemia is often associated with high mortality, and Candida albicans, Candida tropicalis, Candida glabrata, and Candida parapsilosis are common causes of this disease. The pathogenicity characteristics of specific Candida spp. that cause candidemia in Thailand are poorly understood. This study aimed to characterize the virulence factors of Candida spp. Thirty-eight isolates of different Candida species from blood cultures were evaluated for their virulence properties, including exoenzyme and biofilm production, cell surface hydrophobicity, tissue invasion, epithelial cell damage, morphogenesis, and phagocytosis resistance; the identity and frequency of mutations in ERG11 contributing to azole-resistance were also determined. C. albicans had the highest epithelial cell invasion rate and phospholipase activity, with true hyphae formation, whereas C. tropicalis produced the most biofilm, hydrophobicity, protease activity, and host cell damage and true hyphae formation. ERG11 mutations Y132F and S154F were observed in all azole-resistant C. tropicalis. C. glabrata had the most hemolytic activity while cell invasion was low with no morphologic transition. C. glabrata was more easily phagocytosed than other species. C. parapsilosis generated pseudohyphae but not hyphae and did not exhibit any trends in exoenzyme production. This knowledge will be crucial for understanding the pathogenicity of Candida spp. and will help to explore antivirulence-based treatment.

Adaptation to an amoeba host drives selection of virulence-associated traits and genetic variation in saprotrophic Candida albicans

“…In contrast, exposed isolates MS and F did not show differences in hyphal formation when compared to their unexposed isolates ( Figure 2A ). Next, to assess fungal-associated cytotoxicity, we measured the release of LDH by the A549 cells ( Saiprom et al., 2023 ). We investigated whether this cytotoxicity was present during interactions with host-exposed C. albicans isolates.…”

First Report of the Emerging Pathogen Kodamaea ohmeri in Honduras

“…The isolates had a high potential for producing extracellular enzymes, specifically proteases, phospholipase, and hemolysin. Hydrolytic enzymes have an important role in adhering to and infiltrating host cells [ 20 , 22 , 46 ]. Proteases facilitate the entry into cells by breaking down proteins like albumin, collagen, and mucin.…”

“…Biofilm formation was determined according to the protocol previously published by Saiprom et al, 2023 [ 22 ], with modifications. Briefly, the isolates were cultured in a YPD medium overnight at 37 °C.…”

“…The invasion assays were carried out according to the methodology proposed by Faria-Gonçalves et al, 2022 and Saiprom et al, 2023 [ 22 , 24 ], with modifications. Briefly, RAW 264.7 macrophages were reactivated in culture dishes with Dulbecco’s modified Eagle’s medium (DMEM) (Merck, Darmstadt, Germany) supplemented with 5% fetal bovine serum (FBS) (GIBCO TM , Fisher Scientific Inc., Madrid, Spain).…”

“…Adherence tests were performed following previously published protocols with modifications [ 22 , 24 ]. For the adhesion assays, the HeLa cell line was used, which was cultured on plates with DMEM medium supplemented with 5% FBS, which was incubated at 37 °C in 5% CO 2 until 80% confluency was observed.…”