title: Identification of biomarkers for periodontal disease using the immunoproteomics approach.
abstract: BACKGROUND
  Periodontitis is one of the most common oral diseases associated with the host's immune response against periodontopathogenic infection. Failure to accurately diagnose the stage of periodontitis has limited the ability to predict disease status. Therefore, we aimed to look for reliable diagnostic markers for detection or differentiation of early stage periodontitis using the immunoprotemic approach.
  
  
  METHODS
  In the present study, patient serum samples from four distinct stages of periodontitis (i.e., mild chronic, moderate chronic, severe chronic, and aggressive) and healthy controls were subjected to two-dimensional gel electrophoresis (2-DE), followed by silver staining. Notably, we consistently identified 14 protein clusters in the sera of patients and normal controls.
  
  
  RESULTS
  Overall, we found that protein levels were comparable between patients and controls, with the exception of the clusters corresponding to A1AT, HP, IGKC and KNG1 (p < 0.05). In addition, the immunogenicity of these proteins was analysed via immunoblotting, which revealed differential profiles for periodontal disease and controls. For this reason, IgM obtained from severe chronic periodontitis (CP) sera could be employed as a suitable autoantibody for the detection of periodontitis.
  
  
  CONCLUSIONS
  Taken together, the present study suggests that differentially expressed host immune response proteins could be used as potential biomarkers for screening periodontitis. Future studies exploring the diagnostic potential of such factors are warranted.
authors.affiliation: Department of Oral Science & Craniofacial, Faculty of Dentistry, University of Malaya , Kuala Lumpur , Malaysia.
authors.forename: Jesinda P
authors.initials: JP
authors.lastname: Kerishnan
authors.affiliation: Faculty of Dentistry, University of Malaya , Kuala Lumpur , Malaysia.
authors.forename: Sani
authors.initials: S
authors.lastname: Mohammad
authors.affiliation: Faculty of Dentistry, University of Malaya , Kuala Lumpur , Malaysia.
authors.forename: Muhamad Shaifunizam
authors.initials: MS
authors.lastname: Alias
authors.affiliation: Laboratory of Biotechnology, Institute of Win Men Biotech , Sungai Bakap, Pulau Pinang , Malaysia.
authors.forename: Alan Kang-Wai
authors.initials: AK
authors.lastname: Mu
authors.affiliation: Department of Restorative Dentistry, Faculty of Dentistry, University of Malaya , Kuala Lumpur , Malaysia.
authors.forename: Rathna Devi
authors.initials: RD
authors.lastname: Vaithilingam
authors.affiliation: Department of Restorative Dentistry, Faculty of Dentistry, University of Malaya , Kuala Lumpur , Malaysia.
authors.forename: Nor Adinar
authors.initials: NA
authors.lastname: Baharuddin
authors.affiliation: Department of Restorative Dentistry, Faculty of Dentistry, University of Malaya , Kuala Lumpur , Malaysia.
authors.forename: Syarida H
authors.initials: SH
authors.lastname: Safii
authors.affiliation: Department of Oro-Maxillofacial Surgical & Medical Sciences, Faculty of Dentistry, University of Malaya , Kuala Lumpur , Malaysia.
authors.forename: Zainal Ariff
authors.initials: ZA
authors.lastname: Abdul Rahman
authors.affiliation: Chen Dental Specialist Clinic , Kuching, Sarawak , Malaysia.
authors.forename: Yu Nieng
authors.initials: YN
authors.lastname: Chen
authors.affiliation: Department of Oral Science & Craniofacial, Faculty of Dentistry, University of Malaya, Kuala Lumpur, Malaysia; Oral Cancer Research and Coordinating Centre, Faculty of Dentistry, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Yeng
authors.initials: Y
authors.lastname: Chen
keywords: Biomarker; Immunoblotting; Periodontal disease; Proteomics; Serum immunogenic protein; Two-dimensional electrophoresis