Optimizing a Candida biofilm microtiter plate model for measurement of antifungal susceptibility by tetrazolium salt assay
Open accessAbstract
Candida spp. infect medical devices, such as venous and urinary catheters, by adhering to the surface and forming a community of drug-resistant cells surrounded by a matrix. The ability to measure drug activity during this biofilm mode of growth is of interest for the investigation of resistance mechanisms and novel antifungal therapies. The tetrazolium salt (XTT) reduction assay is the test most commonly used to estimate viable biofilm growth and to examine the impact of biofilm therapies. The primary goal of the current experiments was to identify assay variables that affect the XTT assay result in order to improve assay reproducibility, sensitivity, and throughput for the study of antifungal activity. The species used in the current studies included Candida albicans , C. parapsilosis , and C. glabrata . The assay variables that were studied included the impact of culture conditions, the duration of biofilm growth, the timing and frequency of drug administration, the XTT source and concentration, and the duration of XTT incubation. The conditions that impacted the assay readout and altered assay sensitivity included the duration of biofilm growth, the frequency of drug dosing, and the duration of XTT incubation. Several factors were found to reduce time and assay expense, including the elimination of washing steps, the shortening of incubation times, and the use of lower XTT concentrations. A description of assay pitfalls and troubleshooting is included. Recognition of these technical variables should allow investigators to better design reproducible biofilm therapeutic studies.
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MBECs in biofilm conditions were assessed by the XTT reduction assay as previously described, with minor modifications.
“MBECs in biofilm conditions were assessed by the tetrazolium salt (XTT) reduction assay as previously described (66, 67), with minor modifications.”
From Ume6-dependent pathways of morphogenesis and biofilm formation in <i>Candida auris</i> (2024) · cites this paper as [67]
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- Authors
- Nett, J. E., Cain, M. T., Crawford, K., & Andes, D. R.
- Affiliations
- University of Wisconsin–Madison (US)
- Venue
- Journal of Clinical Microbiology
- Publisher
- American Society for Microbiology
- Published
- 2011-04
- Volume
- 49
- Issue
- 4
- Pages
- 1426-1433
- ISSN
- 0095-1137 (ISSN-L)
- 1098-660X
- PMC
- PMC3122839
- OpenAlex
- W2039795845
- Cited by
- 153
- References
- 9
- Citations by year
- 2026: 4 · 2025: 7 · 2024: 7 · 2023: 8 · 2022: 10 · 2021: 15 · 2020: 15 · 2019: 9 · 2018: 16 · 2017: 18 · 2016: 13 · 2015: 3 · 2014: 7 · 2013: 8 · 2012: 9
- FWCI
- 6.07
- Type
- journal article
- Language
- en
- Open access
- green
- www.ncbi.nlm.nih.gov
- Locations
- Journal of Clinical Microbiology (publishedVersion)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- Funders
- U.S. Department of Veterans Affairs
- National Institutes of Health
- National Heart, Lung, and Blood Institute (T32HL007899)
- National Institute of Allergy and Infectious Diseases (R01AI073289)
- Topics
- Health Sciences › Medicine › Infectious Diseases › Antifungal resistance and susceptibility
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Bacterial biofilms and quorum sensing
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Fungal and yeast genetics research
- Keywords
- Candida biofilms, antifungal susceptibility, Candida albicans, Candida parapsilosis, Candida glabrata, assay reproducibility, antifungal resistance
- MeSH terms
- Antifungal Agents, Candida, Humans, Microbial Sensitivity Tests, Sensitivity and Specificity, Tetrazolium Salts, Reproducibility of Results, Biofilms, Microbial Viability
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