A three-phase in-vitro system for studying Pseudomonas aeruginosa adhesion and biofilm formation upon hydrogel contact lenses
- Equal contributors
1 Department of Hygiene and Environmental Medicine, Ernst Moritz Arndt University Greifswald, Greifswald, Germany
2 School of Pharmacy and Pharmaceutical Sciences, The University of Manchester, Manchester, UK
3 Competence Center for Functional Genomics, Ernst Moritz Arndt University Greifswald, Greifswald, Germany
4 Department of Microbiology, Ernst Moritz Arndt University Greifswald, Greifswald, Germany
5 Institute of Community Medicine, Ernst Moritz Arndt University Greifswald, Greifswald, Germany
BMC Microbiology 2010, 10:282 doi:10.1186/1471-2180-10-282Published: 9 November 2010
Pseudomonas aeruginosa is commonly associated with contact lens (CL) -related eye infections, for which bacterial adhesion and biofilm formation upon hydrogel CLs is a specific risk factor. Whilst P. aeruginosa has been widely used as a model organism for initial biofilm formation on CLs, in-vitro models that closely reproduce in-vivo conditions have rarely been presented.
In the current investigation, a novel in-vitro biofilm model for studying the adherence of P. aeruginosa to hydrogel CLs was established. Nutritional and interfacial conditions similar to those in the eye of a CL wearer were created through the involvement of a solid:liquid and a solid:air interface, shear forces and a complex artificial tear fluid. Bioburdens varied depending on the CL material and biofilm maturation occurred after 72 h incubation. Whilst a range of biofilm morphologies were visualised including dispersed and adherent bacterial cells, aggregates and colonies embedded in extracellular polymer substances (EPS), EPS fibres, mushroom-like formations, and crystalline structures, a compact and heterogeneous biofilm morphology predominated on all CL materials.
In order to better understand the process of biofilm formation on CLs and to test the efficacy of CL care solutions, representative in-vitro biofilm models are required. Here, we present a three-phase biofilm model that simulates the environment in the eye of a CL wearer and thus generates biofilms which resemble those commonly observed in-situ.