Significance of hyphae formation in virulence of Candida tropicalis and transcriptomic analysis of hyphal cells.
Recently, the proportion of Candida tropicalis in clinical isolates has significantly increased. Some C. tropicalis strains colonize the skin or mucosal surfaces as commensals; others trigger invasive infection. To date, the pathogenicity of C. tropicalis has not been thoroughly researched. This study reports several virulence factors, including biofilm and hyphae formation, proteinase, phospholipase, lipase and hemolytic activity, in 52 clinical isolates of C. tropicalis collected from five hospitals in four provinces of China. Some C. tropicalis tended to produce more hyphae than others in the same circumstance. Six C. tropicalis strains with different morphologies were injected into mice via the tail vein, and the survival proportions and fungal burdens of the strains were evaluated. Hyphal production by C. tropicalis was associated with stronger virulence. RNA sequencing revealed that C. tropicalis with more hyphae up-regulated several genes involved in morphological differentiation and oxidative response, including IF2, Atx1, and Sod2. It appears that hyphal formation plays a vital role in the pathogenicity of C. tropicalis, and interacts with the oxidative stress response to strengthen the organism's virulence.
Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
Cen
C
Jiang
Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
Zhen
Z
Li
Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
Lihua
L
Zhang
Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
Yuan
Y
Tian
Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
Danfeng
D
Dong
Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China. Electronic address: pyb9861@sina.com.
Yibing
Y
Peng
D000818:Animals; D018441:Biofilms; D041022:Candida tropicalis / Q000472:pathogenicity / Q000502:physiology*; D002177:Candidiasis / Q000382:microbiology; D016000:Cluster Analysis; D019295:Computational Biology / Q000379:methods; D005260:Female; D020869:Gene Expression Profiling; D015971:Gene Expression Regulation, Enzymologic; D015966:Gene Expression Regulation, Fungal; D025301:Hyphae / Q000235:genetics*; D051379:Mice; D015203:Reproducibility of Results; D059467:Transcriptome; D014774:Virulence / Q000235:genetics; D037521:Virulence Factors / Q000235:genetics
D037521:Virulence Factors
Candida tropicalis; Hyphae; RNA-seq; Virulence