title: Cytokine degradation by biofilms of Porphyromonas gingivalis.
abstract: The aim of this study was to determine whether biofilms of Porphyromonas gingivalis could proteolytically degrade the cytokines interleukin (IL)-1beta, IL-6, or IL-1 receptor antagonist (IL-1ra). Biofilms were grown on membrane filters on the surface of Wilkins-Chalgren blood agar. The biofilms were removed from the plates, and solutions containing 2.5 microg/ml of each cytokine were added. Following incubation for up to 4.0 h, supernatants from the biofilms were subjected to SDS-PAGE. The separated proteins were transferred by Western blotting to PVDF membranes and probed with peroxidase-conjugated antibodies recognizing both the intact cytokines and their degradation products. After 2 h, no intact IL-1beta, IL-6, or IL-1ra were detectable. Cytokine proteolysis also occurred in the presence of horse serum. These results demonstrate that biofilm-grown P. gingivalis can degrade both pro- and anti-inflammatory cytokines and so may be able to perturb cytokine networks in vivo by eliminating cytokines from the local environment.
authors.affiliation: Department of Microbiology, Eastman Dental Institute, University College London, 256 Grays Inn Road, London WC1X 8LD, UK.
authors.forename: J
authors.initials: J
authors.lastname: Fletcher
authors.forename: S
authors.initials: S
authors.lastname: Nair
authors.forename: S
authors.initials: S
authors.lastname: Poole
authors.forename: B
authors.initials: B
authors.lastname: Henderson
authors.forename: M
authors.initials: M
authors.lastname: Wilson
mesh_terms: D018441:Biofilms; D015153:Blotting, Western; D007375:Interleukin-1 / Q000378:metabolism*; D015850:Interleukin-6 / Q000378:metabolism*; D016966:Porphyromonas gingivalis / Q000378:metabolism* / Q000502:physiology; D017472:Receptors, Interleukin-1 / Q000378:metabolism*
chemical_list: D007375:Interleukin-1; D015850:Interleukin-6; D017472:Receptors, Interleukin-1