Filling the void: an optimized polymicrobial interkingdom biofilm model for assessing novel antimicrobial agents in endodontic infection

Abusrewil, S., Brown, J. L. , Delaney, C. D., Butcher, M. C., Kean, R., Gamal, D., Scott, J. A. , McLean, W. and Ramage, G. (2020) Filling the void: an optimized polymicrobial interkingdom biofilm model for assessing novel antimicrobial agents in endodontic infection. Microorganisms, 8(12), 1988. (doi: 10.3390/microorganisms8121988) (PMID:33327403) (PMCID:PMC7764896)

Abstract

There is a growing realization that endodontic infections are often polymicrobial, and may contain Candida spp. Despite this understanding, the development of new endodontic irrigants and models of pathogenesis remains limited to mono-species biofilm models and is bacterially focused. The purpose of this study was to develop and optimize an interkingdom biofilm model of endodontic infection and use this to test suitable anti-biofilm actives. Biofilms containing Streptococcus gordonii, Fusobacterium nucleatum, Porphyromonas gingivalis, and Candida albicans were established from ontological analysis. Biofilms were optimized in different media and atmospheric conditions, prior to quantification and imaging, and subsequently treated with chlorhexidine, EDTA, and chitosan. These studies demonstrated that either media supplemented with serum were equally optimal for biofilm growth, which were dominated by S. gordonii, followed by C. albicans. Assessment of antimicrobial activity showed significant effectiveness of each antimicrobial, irrespective of serum. Chitosan was most effective (3 log reduction), and preferentially targeted C. albicans in both biofilm treatment and inhibition models. Chitosan was similarly effective at preventing biofilm growth on a dentine substrate. This study has shown that a reproducible and robust complex interkingdom model, which when tested with the antifungal chitosan, supports the notion of C. albicans as a key structural component.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Kean, Mr Ryan and Scott, Dr James and Brown, Dr Jason and Gamal, Ms Dalia and Delaney, Mr Christopher and Mclean, Professor William and Butcher, Mr Mark and Ramage, Professor Gordon and Abusrewil, Sumaya
• Authors: Abusrewil, S., Brown, J. L., Delaney, C. D., Butcher, M. C., Kean, R., Gamal, D., Scott, J. A., McLean, W., and Ramage, G.
• College/School: College of Medical Veterinary and Life Sciences > School of Medicine, Dentistry & Nursing > Dental School
• Journal Name: Microorganisms
• Publisher: MDPI
• ISSN: 2076-2607
• ISSN (Online): 2076-2607
• Published Online: 14 December 2020
• Copyright Holders: Copyright © 2020 The Authors
• First Published: First published in Microorganisms 8(12): 1988
• Publisher Policy: Reproduced under a Creative Commons License

Project Code	Award No	Project Name	Principal Investigator	Funder's Name	Funder Ref	Lead Dept
173112		Understanding processes and mechanisms affecting the oral microbiome using OMICs approaches	Gordon Ramage	Biotechnology and Biological Sciences Research Council (BBSRC)	BB/P504567/1	Med - Dental School