title: Crevicular Porphyromonas gingivalis-specific immunoglobulin A levels in healthy and periodontitis-affected Thai cohorts.
abstract: Abstract Aim:  Immunoglobulin A is a key humoral immune component involved in defense mechanisms against infections. Periodontitis, the chronic inflammatory disease causing periodontal destruction, adversely affects adults worldwide, including Thailand. As the development of periodontitis is partly mediated by immune components, levels of total and Porphyromonas gingivalis-specific immunoglobulin A in gingival crevicular fluid of Thai cohorts were studied.
  
  
  METHODS
  Gingival crevicular fluid was collected from 24 patients with severe generalized chronic periodontitis and 22 healthy controls. The amount and concentration of total and Porphyromonas gingivalis-specific immunoglobulin A in each gingival crevicular fluid sample were determined by enzyme-linked immunosorbent assay.
  
  
  RESULTS
  The control group contained the highest concentrations of both types of gingival crevicular fluid-immunoglobulin A, but the lowest levels of these antibodies were found in the deep sites of the periodontitis group. Moreover, the concentrations of gingival crevicular fluid-immunoglobulin A and the degree of periodontitis severity appeared to have an inverse relationship. There was no significant difference in the amounts of gingival crevicular fluid-immunoglobulin A in the control and periodontitis groups.
  
  
  CONCLUSIONS
  This study supports the hypothesis that high concentrations of specific gingival crevicular fluid-immunoglobulin A antibodies directed against Porphyromonas gingivalis, a potent periodontic microorganism, could retard periodontitis development.
authors.affiliation: Department of Oral Microbiology, Faculty of Dentistry, Mahidol University, Bangkok, Thailand Department of General Dentistry, Faculty of Dentistry, Srinakarinwirot University, Bangkok, Thailand Department of Oral Medicine, Faculty of Dentistry, Mahidol University, Bangkok, Thailand.
authors.forename: Suwan
authors.initials: S
authors.lastname: Choonharuangdej
authors.forename: Aurasri
authors.initials: A
authors.lastname: Chutinet
authors.forename: Yosvimol
authors.initials: Y
authors.lastname: Kuphasuk
mesh_terms: D000328:Adult; D000368:Aged; D000907:Antibodies, Bacterial / Q000032:analysis; D055113:Chronic Periodontitis / Q000276:immunology* / Q000382:microbiology; D015331:Cohort Studies; D003774:Dental Plaque Index; D005260:Female; D005883:Gingival Crevicular Fluid / Q000276:immunology*; D006801:Humans; D007071:Immunoglobulin A, Secretory / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D017622:Periodontal Attachment Loss / Q000276:immunology / Q000382:microbiology; D010512:Periodontal Index; D010514:Periodontal Pocket / Q000276:immunology / Q000382:microbiology; D016966:Porphyromonas gingivalis / Q000276:immunology*; D013785:Thailand; D055815:Young Adult
chemical_list: D000907:Antibodies, Bacterial; D007071:Immunoglobulin A, Secretory
keywords: Porphyromonas gingivalis; enzyme-linked immunosorbent assay; gingival crevicular fluid; immunoglobulin A; periodontitis