title: Blood cell gene expression profiling in subjects with aggressive periodontitis and chronic arthritis.
abstract: BACKGROUND
  Microarray analysis of local and peripheral cells in subjects with immune-inflammatory diseases may identify candidate genes associated with these diseases. The present study identified differentially expressed genes in peripheral blood mononuclear cells (PBMCs) from subjects with untreated localized aggressive periodontitis (LAgP) or generalized aggressive periodontitis (GAgP). Differentially expressed genes were validated in groups of subjects with LAgP, GAgP, juvenile idiopathic arthritis (JIA), or rheumatoid arthritis (RA) and controls.
  
  
  METHODS
  Candidate genes were identified by gene expression profiling of PBMCs using a microarray system in untreated gender-matched subjects with LAgP (N = 2) or GAgP (N = 3) and controls (N = 2) younger than 35 years of age. The microarray results were validated by real-time reverse transcription-polymerase chain reaction (RT-PCR) using PBMCs from 103 individuals, including groups of subjects with LAgP (N = 18), GAgP (N = 27), JIA (N = 10), or RA (N = 23) and controls (N = 25).
  
  
  RESULTS
  Of 53 differentially expressed candidate genes identified in subjects with LAgP, 14 were involved in immune responses and inflammatory processes. Of these, the RT-PCR validation confirmed that Toll-like receptor 2 gene (TLR2) and myomesin 2 gene had a significantly higher expression in subjects with LAgP than in controls. RT-PCR also showed increased expression of TLR2 in subjects with RA. Comparison of subjects with GAgP to controls using microarray analysis identified only three upregulated genes.
  
  
  CONCLUSIONS
  Several genes upregulated in subjects with LAgP were related to immune responses including TLR2 and myomesin 2.
authors.affiliation: Department of Periodontology, School of Dentistry, Faculty of Health Sciences, University of Copenhagen, 20 Nørre Allé, Copenhagen, Denmark.
authors.forename: Lars K
authors.initials: LK
authors.lastname: Sørensen
authors.forename: Anne
authors.initials: A
authors.lastname: Havemose-Poulsen
authors.forename: Søren U
authors.initials: SU
authors.lastname: Sønder
authors.forename: Klaus
authors.initials: K
authors.lastname: Bendtzen
authors.forename: Palle
authors.initials: P
authors.lastname: Holmstrup
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000235:genetics* / Q000276:immunology; D016022:Case-Control Studies; D064211:Connectin; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000378:metabolism*; D008297:Male; D009124:Muscle Proteins / Q000096:biosynthesis / Q000097:blood; D020411:Oligonucleotide Array Sequence Analysis; D010518:Periodontitis / Q000097:blood / Q000235:genetics* / Q000276:immunology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D051195:Toll-Like Receptor 2 / Q000096:biosynthesis* / Q000097:blood; D015854:Up-Regulation
chemical_list: D064211:Connectin; C577299:MYOM1 protein, human; D009124:Muscle Proteins; D051195:Toll-Like Receptor 2