title: Expression of peptidylarginine deiminase-2 and -4, citrullinated proteins and anti-citrullinated protein antibodies in human gingiva.
abstract: OBJECTIVE
  The presence of citrullinated proteins, and peptidylarginine deiminase types -2 (PAD-2) and -4 (PAD-4) in periodontal tissues, determine the presence of anti-cyclic citrullinated protein antibodies (anti-CCP) in gingival crevicular fluid (GCF) and compare the expression of these proteins between inflamed and non-inflamed sites.
  
  
  METHODS
  Tissue sections were stained using antibodies against citrullinated proteins, PAD-2 and PAD-4. RT-PCR was performed to investigate PAD-2 and PAD-4 mRNA in inflamed and non-inflamed gingival tissues. Anti-CCP antibodies in gingival crevicular fluid were detected by ELISA.
  
  
  RESULTS
  Citrullinated proteins, PAD-2 and PAD-4 were detected in gingiva. There was a correlation between inflammation and expression of these proteins. mRNAs for PAD-2 and PAD-4 were detected in both inflamed and non-inflamed gingival tissues. Antibodies to CCP were found mostly in the GCF of individuals with periodontitis.
  
  
  CONCLUSIONS
  PAD-2 and PAD-4 (protein and mRNA) as well as citrullinated proteins are present in inflamed gingiva, and anti-CCP antibodies can be detected in the GCF of some patients. Tissue expression of citrullinated proteins and PAD increased with the severity of inflammation. The presence of anti-CCP antibodies in GCF was almost exclusive to a subset of patients with periodontitis. Increased expression of these proteins in inflamed gingiva lends support to the notion that periodontal inflammation contributes to the inflammatory burden in a similar way to rheumatoid arthritis.
authors.affiliation: Colgate Australian Clinical Dental Research, School of Dentistry, University of Adelaide, Adelaide, South Australia, 5005, Australia.
authors.forename: G P
authors.initials: GP
authors.lastname: Harvey
authors.forename: T R
authors.initials: TR
authors.lastname: Fitzsimmons
authors.forename: A A S S K
authors.initials: AA
authors.lastname: Dhamarpatni
authors.forename: C
authors.initials: C
authors.lastname: Marchant
authors.forename: D R
authors.initials: DR
authors.lastname: Haynes
authors.forename: P M
authors.initials: PM
authors.lastname: Bartold
mesh_terms: D000328:Adult; D010520:Aggressive Periodontitis / Q000276:immunology / Q000473:pathology; D001323:Autoantibodies / Q000032:analysis*; D002227:Carbazoles; D055113:Chronic Periodontitis / Q000276:immunology / Q000473:pathology; D002956:Citrulline / Q000032:analysis* / Q000276:immunology; D004396:Coloring Agents; D042783:Endothelial Cells / Q000473:pathology; D005260:Female; D005347:Fibroblasts / Q000473:pathology; D005881:Gingiva / Q000276:immunology / Q000473:pathology*; D005883:Gingival Crevicular Fluid / Q000737:chemistry / Q000276:immunology; D005884:Gingival Hemorrhage / Q000276:immunology / Q000473:pathology; D005889:Gingival Recession / Q000276:immunology / Q000473:pathology; D006801:Humans; D006867:Hydrolases / Q000032:analysis*; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D010514:Periodontal Pocket / Q000276:immunology / Q000473:pathology; D010518:Periodontitis / Q000276:immunology / Q000473:pathology*; D000080002:Protein-Arginine Deiminase Type 4; D000076342:Protein-Arginine Deiminases; D011506:Proteins / Q000032:analysis* / Q000276:immunology; D012907:Smoking
chemical_list: D001323:Autoantibodies; D002227:Carbazoles; D004396:Coloring Agents; D011506:Proteins; D002956:Citrulline; C020702:3-amino-9-ethylcarbazole; D006867:Hydrolases; C000629235:PADI4 protein, human; D000080002:Protein-Arginine Deiminase Type 4; D000076342:Protein-Arginine Deiminases