A new approach by optical coherence tomography for elucidating biofilm formation by emergent Candida species

PLoS One. 2017 Nov 16;12(11):e0188020. doi: 10.1371/journal.pone.0188020. eCollection 2017.

Abstract

The majority of microorganisms present a community lifestyle, establishing biofilm ecosystems. However, little is known about its formation in emergent Candida species involved in catheter-related infections. Thus, various techniques may be used in the biofilm detection to elucidate structure and clinical impact. In this context, we report the ability of emergent Candida species (Candida haemulonii, C. lusitaniae, C. pelliculosa, C.guilliermondii, C. famata and C. ciferrii) on developing well structured biofilms with cell viability and architecture, using optical coherence tomography (OCT). This new approach was compared with XTT analyses and Scanning Electron Microscopy (SEM). A positive correlation between oxidative activity (XTT) and OCT results (r = 0.8752, p < 0.0001) was observed. SEM images demonstrated cells attachment, multilayer and morphologic characteristics of the biofilm structure. C. lusitaniae was the emergent species which revealed the highest scattering extension length and oxidative metabolism when evaluated by OCT and XTT methods, respectively. Herein, information on C. ciferri biofilm structure were presented for the first time. The OCT results are independently among Candida strains and no species-specific pattern was observed. Our findings strongly contribute for clinical management based on the knowledge of pathogenicity mechanisms involving emergent yeasts.

MeSH terms

  • Biofilms*
  • Candida / classification
  • Candida / physiology*
  • Microscopy, Electron, Scanning
  • Species Specificity
  • Tomography, Optical Coherence / methods*

Grants and funding

The author Rejane Neves received financial support from FACEPE/Brazil to acquire reagents and the necessary materials and Melyna Leite-Andrade received a scholarship from CNPq/Brazil. This study was also funded by CAPES and the National Institute of Photonics (to REdA). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.