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Updated: Aug 23, 2025
Visualization of Biofilm Formation in Candida albicans Using an Automated Microfluidic Device
Published on: December 14, 2017
Assessment of Biofilm Formation by Candida albicans Strains Isolated from Hemocultures and Their Role in Pathogenesis
Sabi Pokhrel1, Nawarat Boonmee2, Orawan Tulyaprawat1
1Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.
Abstract:
Candida albicans, an opportunistic pathogen, has the ability to form biofilms in the host or within medical devices in the body. Biofilms have been associated with disseminated/invasive disease with increased severity of infection by disrupting the host immune response and prolonging antifungal treatment. In this study, the in vivo virulence of three strains with different biofilm formation strengths, that is, non-, weak-, and strong biofilm formers, was evaluated using the zebrafish model. The survival assay and fungal tissue burden were measured. Biofilm-related gene expressions were also investigated. The survival of zebrafish, inoculated with strong biofilms forming C. albicans,, was significantly shorter than strains without biofilms forming C. albicans. However, there were no statistical differences in the burden of viable colonogenic cell number between the groups of the three strains tested. We observed that the stronger the biofilm formation, the higher up-regulation of biofilm-associated genes. The biofilm-forming strain (140 and 57), injected into zebrafish larvae, possessed a higher level of expression of genes associated with adhesion, attachment, filamentation, and cell proliferation, including eap1, als3, hwp1, bcr1, and mkc1 at 8 h. The results suggested that, despite the difference in genetic background, biofilm formation is an important virulence factor for the pathogenesis of C. albicans. However, the association between biofilm formation strength and in vivo virulence is controversial and needs to be further studied.
Insights
Stronger biofilm formation in Candida albicans correlates with increased virulence and shorter zebrafish survival. However, fungal burden did not differ, suggesting complex interactions in infection pathogenesis.
Area of Science:
- Microbiology
- Infectious Diseases
- Pathogenesis
Background:
- * *Candida albicans* forms biofilms, increasing infection severity and treatment resistance.
- * Biofilms disrupt host immunity and prolong antifungal therapy.
- * Understanding biofilm-related virulence is crucial for managing invasive candidiasis.
Purpose of the Study:
- * To evaluate the *in vivo* virulence of *C. albicans* strains with varying biofilm strengths.
- * To investigate the relationship between biofilm formation and pathogenesis in a zebrafish model.
- * To analyze the expression of biofilm-associated genes during infection.
Main Methods:
- * Utilized a zebrafish model to assess *in vivo* virulence of non-, weak-, and strong biofilm-forming *C. albicans* strains.
- * Measured zebrafish survival rates and fungal tissue burden.
- * Quantified the expression of key biofilm-related genes (e.g., *eap1*, *als3*, *hwp1*, *bcr1*, *mkc1*).
Main Results:
- * Zebrafish survival was significantly reduced when inoculated with strong biofilm-forming strains.
- * No significant differences in fungal tissue burden were observed across strains.
- * Stronger biofilm formation correlated with higher expression of adhesion, filamentation, and proliferation genes.
Conclusions:
- * Biofilm formation is a significant virulence factor in *C. albicans* pathogenesis.
- * The strength of biofilm formation influences *in vivo* virulence.
- * Further research is needed to clarify the complex association between biofilm strength and virulence.
