title: Degradation of immunoglobulin G by periodontal bacteria.
abstract: Several subgingival microorganisms were tested for their ability to utilize human immunoglobulin G (IgG) as a substrate for growth. This was done using a protein-free chemically defined medium, supplemented with IgG. Stimulation of growth was observed for Capnocytophaga ochracea, Porphyromonas asaccharolytica, Porphyromonas endodontalis, Porphyromonas gingivalis, Prevotella intermedia, Prevotella oralis, Lactobacillus catenaforme and Streptococcus intermedius. Immunoelectrophoresis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis and a protein assay demonstrated that P. intermedia and P. endodontalis completely degraded the protein chains of IgG. Partial breakdown of IgG was observed for P. asaccharolytica and C. ochracea, whereas P. oralis cleaved the IgG heavy chain, yielding Fc and Fab fragments. All these bacteria utilized IgG as a substrate for growth. Binding studies using an enzyme-linked immunosorbent assay, revealed complete loss of in vitro antigen-antibody binding capacity after incubation of specific IgG with P. endodontalis and partial loss of binding with P. intermedia, P. gingivalis, C. ochracea or Fusobacterium nucleatum. Degradation or inactivation of IgG by oral bacteria is thought to be important in the causation of polymicrobial infections.
authors.affiliation: Department of Periodontology and Preventive Dentistry, University of Nijmegen, the Netherlands.
authors.forename: H J
authors.initials: HJ
authors.lastname: Jansen
authors.forename: J S
authors.initials: JS
authors.lastname: van der Hoeven
authors.forename: C W
authors.initials: CW
authors.lastname: van den Kieboom
authors.forename: J H
authors.initials: JH
authors.lastname: Göertz
authors.forename: P J
authors.initials: PJ
authors.lastname: Camp
authors.forename: J A
authors.initials: JA
authors.lastname: Bakkeren
mesh_terms: D000190:Actinomyces / Q000254:growth & development / Q000378:metabolism; D000907:Antibodies, Bacterial / Q000378:metabolism*; D000937:Antigen-Antibody Reactions; D001421:Bacteria, Anaerobic / Q000254:growth & development / Q000378:metabolism*; D001439:Bacteroides / Q000254:growth & development / Q000378:metabolism; D002206:Capnocytophaga / Q000254:growth & development / Q000378:metabolism; D003470:Culture Media; D017753:Ecosystem; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D005051:Eubacterium / Q000254:growth & development / Q000378:metabolism; D016967:Fusobacterium nucleatum / Q000254:growth & development / Q000378:metabolism; D006801:Humans; D007074:Immunoglobulin G / Q000378:metabolism*; D007778:Lactobacillus / Q000254:growth & development / Q000378:metabolism; D009844:Oligosaccharides / Q000378:metabolism; D010455:Peptides / Q000378:metabolism; D010519:Periodontium / Q000276:immunology / Q000382:microbiology*; D017861:Porphyromonas / Q000254:growth & development / Q000378:metabolism; D013291:Streptococcus / Q000254:growth & development / Q000378:metabolism; D015163:Superinfection / Q000276:immunology*; D013559:Symbiosis
chemical_list: D000907:Antibodies, Bacterial; D003470:Culture Media; D007074:Immunoglobulin G; D009844:Oligosaccharides; D010455:Peptides