Comparison of counting methods of the morphological forms of Candida albicans

• Grant number: 17/24591-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2018
• End date: December 31, 2018
• Field of knowledge: Health Sciences - Dentistry
• Principal Investigator: Ewerton Garcia de Oliveira Mima
• Grantee: Gabriela Cristina Zanatta
• Host Institution: Faculdade de Odontologia (FOAr). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

Candida albicans is the main fungal pathogen of humans. This microorganism shows the ability to develop in different morphologies (yeast, pseudohifas and hyphae), called polymorphism. The C. albicans polymophism compromises the usual quantification methods, which could jeopardize procedures that require accuracy, such as therapeutic methods as well as research involving filamentous fungi. Thus, the aim of this study will be to compare the methods of quantification of C. albicans by colony forming units (CFU) and by quantitative polymerase chain reaction (qPCR) with the counting of viable cells and cell nuclei in In Cell Analyzer 2000. Standardized planktonic cultures of C. albicans in yeast and filamentous form will be grown and submitted individually or mixed to the three methods of quantification: CFU/mL, cell count and qPCR. For In Cell Analyzer 2000 counts, the fungal suspensions will be treated with different fluorescent markers to evidence viable cells, non-viable cells, and cell nuclei. For qPCR a cross-linking DNA ligand will be used to exclude DNA from non-viable cells with membrane damage. The data will be submitted to intraclass correlation coefficient tests and correlation analysis, which, if present, will be followed by a linear and multiple regression study (± = 5%).