title: Elevated tumor necrosis factor-alpha expression in periapical lesions infected by Epstein-Barr virus.
abstract: BACKGROUND
  In apical periodontitis, there is an intense inflammatory response to endodontopathogenic bacteria, an essential component of the pathogenic microbiota. The inflammation can be aggravated by herpesviruses acting as nonessential pathogens in periapical lesions. This study aimed to determine the levels of tumor necrosis factor-alpha (TNF-α) and transforming growth factor-beta (TGF-β) in periapical lesions in relation to local occurrence of Epstein-Barr virus (EBV), human cytomegalovirus (HCMV), human herpesvirus 6 (HHV-6), and human herpesvirus 8 (HHV-8).
  
  
  METHODS
  Fifty-eight samples with apical periodontitis and 20 clinically healthy gingival control tissues were collected. Viral DNA was determined with nested polymerase chain reaction, and cytokine mRNA expression was detected with real-time polymerase chain reaction assays.
  
  
  RESULTS
  Periapical lesions harbored EBV (75.9%) and HHV-6 (22.4%) at significantly higher frequencies compared with controls (P < .000001 and P < .05, respectively), whereas HCMV (12%) and HHV-8 (0%) occurred rarely. The median TNF-α expression was 13 times higher (P < .001) and TGF-β expression was 5 times higher in periapical lesions than in controls (P < .001). TNF-α expression was significantly higher in EBV-positive lesions than in EBV-negative lesions (P = .032). Presence of symptoms, lesion size, and infection by HCMV or HHV-6 had no significant association with either TNF-α or TGF-β expression.
  
  
  CONCLUSIONS
  The herpesviral component of the endodontic microbiota did not correlate with TGF-β expression, whereas EBV infection was associated with a median 1.5 times further elevation of the high TNF-α expression characteristic for periapical lesions.
authors.affiliation: Medical and Health Science Center, University of Debrecen, Debrecen, Hungary.
authors.forename: Katinka
authors.initials: K
authors.lastname: Hernádi
authors.forename: Eszter
authors.initials: E
authors.lastname: Gyöngyösi
authors.forename: Beáta
authors.initials: B
authors.lastname: Mészáros
authors.forename: Levente
authors.initials: L
authors.lastname: Szakács
authors.forename: Anita
authors.initials: A
authors.lastname: Szalmás
authors.forename: Eszter
authors.initials: E
authors.lastname: Csoma
authors.forename: Richárd
authors.initials: R
authors.lastname: Mogyorósi
authors.forename: Levente
authors.initials: L
authors.lastname: Czompa
authors.forename: György
authors.initials: G
authors.lastname: Veress
authors.forename: István
authors.initials: I
authors.lastname: Varga
authors.forename: Ildikó Judit
authors.initials: IJ
authors.lastname: Márton
authors.forename: József
authors.initials: J
authors.lastname: Kónya
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D003587:Cytomegalovirus; D004279:DNA, Viral / Q000032:analysis; D020031:Epstein-Barr Virus Infections / Q000276:immunology* / Q000378:metabolism; D004854:Herpesvirus 4, Human; D015654:Herpesvirus 6, Human; D019288:Herpesvirus 8, Human; D006801:Humans; D008875:Middle Aged; D010485:Periapical Periodontitis / Q000276:immunology* / Q000378:metabolism / Q000473:pathology / Q000821:virology*; D060888:Real-Time Polymerase Chain Reaction; D018709:Statistics, Nonparametric; D016212:Transforming Growth Factor beta / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*
chemical_list: D004279:DNA, Viral; D016212:Transforming Growth Factor beta; D014409:Tumor Necrosis Factor-alpha