title: Gingival fibroblasts from periodontitis patients exhibit inflammatory characteristics in vitro.
abstract: OBJECTIVE
  Gingival fibroblasts (GFs) are an important regulatory cell type in the progression of periodontitis. This study aimed to compare the expression levels of genes associated with inflammation, extracellular matrix degradation and bone destruction in GFs isolated from healthy and periodontitis subjects in the absence and presence of Porphyromonas gingivalis.
  
  
  METHODS
  Primary GFs from healthy (n=10) and periodontitis subjects (n=10) were stimulated in vitro with viable P. gingivalis ATCC 49417 and 3 clinical isolates of P. gingivalis with type II fimbriae from one healthy subject (KUMC-H1) and two periodontitis patients (KUMC-P1, -P2). The mRNA expression of proinflammatory cytokines (interleukin (IL)-6, IL-8, IL-1B), anti-inflammatory cytokines (IL-4, IL-10), matrix metalloproteinase (MMP)-1 and 2, tissue inhibitor matrix metalloproteinase (TIMP)-3 and osteoprotegerin (OPG) were assessed using real-time PCR. The levels of IL-6, IL-1β and TIMP-3 protein were measured by an enzyme-linked immunosorbent assay.
  
  
  RESULTS
  The mRNA expression of IL-6, IL-1B and TIMP-3 was higher in the periodontitis group compared with the healthy group, whereas IL-4 expression was higher in the healthy group both in the absence and presence of the P. gingivalis strains. The expression levels of IL-6, IL-1β and TIMP-3 protein were also higher in the periodontitis group in the absence and/or presence of the P. gingivalis strains. There was inter-strain variability among P. gingivalis strains in the ability to induce expression of the proinflammatory cytokines, MMPs and OPG and in the ability to degrade IL-6 protein.
  
  
  CONCLUSIONS
  High expression of proinflammatory cytokines and TIMP-3 and low expression of IL-4 can be a signature of GFs associated with periodontitis.
authors.affiliation: Department of Oromaxillofacial Infection & Immunity, BK21 CLS, School of Dentistry and Dental Research Institute, Seoul National University, Seoul, Republic of Korea.
authors.forename: Keum Jin
authors.initials: KJ
authors.lastname: Baek
authors.forename: Youngnim
authors.initials: Y
authors.lastname: Choi
authors.forename: Suk
authors.initials: S
authors.lastname: Ji
mesh_terms: D018450:Disease Progression; D004797:Enzyme-Linked Immunosorbent Assay; D005347:Fibroblasts / Q000378:metabolism* / Q000382:microbiology*; D015870:Gene Expression; D005838:Genotype; D005881:Gingiva / Q000166:cytology* / Q000382:microbiology; D006801:Humans; D066298:In Vitro Techniques; D016753:Interleukin-10 / Q000378:metabolism; D053583:Interleukin-1beta / Q000378:metabolism; D015847:Interleukin-4 / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D010518:Periodontitis / Q000378:metabolism* / Q000382:microbiology; D016966:Porphyromonas gingivalis / Q000235:genetics / Q000302:isolation & purification; D060888:Real-Time Polymerase Chain Reaction; D019717:Tissue Inhibitor of Metalloproteinase-3 / Q000378:metabolism
chemical_list: D053583:Interleukin-1beta; D015850:Interleukin-6; D019717:Tissue Inhibitor of Metalloproteinase-3; D016753:Interleukin-10; D015847:Interleukin-4
keywords: Gingival fibroblast; Inflammatory cytokines; Periodontitis; Porphyromonas gingivalis