title: Marginal periodontium as a potential reservoir of human papillomavirus in oral mucosa.
abstract: BACKGROUND
  Although human papillomaviruses (HPVs) are associated with a number of proliferative epithelial lesions including squamous cell malignancies, they can also be detected in the normal oral mucosa in 10% to 20% of the adult population. However, the point of entry and the site of replication of HPV in the oral cavity are not known. Since the gingival pocket is the only site in the oral mucosa where basal cells, known to be targets of HPV at other mucosal sites, are normally exposed to the environment, we hypothesized that this could be the site of latent HPV.
  
  
  METHODS
  Gingival biopsies taken from 38 individuals with clinically diagnosed periodontal disease were examined. The presence of HPV DNA was studied by using nested PCR (polymerase chain reaction with MY09/MY11 and GP05+/GP06+ primers targeting the L1 region of HPV), followed by subsequent hybridization with a cocktail of 12 high-risk HPV oligoprobes and in situ hybridization (ISH) with probes for HPV screening and the HPV subtype 16.
  
  
  RESULTS
  In the present study, high-risk HPV types were detected in 26% (8/31) of the gingival biopsies with PCR. By using in situ hybridization, the viral DNA was localized to the coronal part of the junctional epithelium in the gingival pocket.
  
  
  CONCLUSIONS
  The results suggest that the periodontal pocket might serve as a reservoir of HPVs in oral mucosa. While having important implications in understanding the HPV transmission, this observation does not rule out the possibility that HPV may be involved in the initiation of periodontal disease.
authors.affiliation: Department of Anatomy, Institute of Biomedicine, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
authors.forename: Marketta
authors.initials: M
authors.lastname: Hormia
authors.forename: Jaana
authors.initials: J
authors.lastname: Willberg
authors.forename: Hellevi
authors.initials: H
authors.lastname: Ruokonen
authors.forename: Stina
authors.initials: S
authors.lastname: Syrjänen
mesh_terms: D000328:Adult; D002467:Cell Nucleus / Q000821:virology; D004279:DNA, Viral / Q000032:analysis; D004846:Epithelial Attachment / Q000821:virology; D004848:Epithelium / Q000821:virology; D005881:Gingiva / Q000821:virology*; D005888:Gingival Pocket / Q000821:virology; D006801:Humans; D017403:In Situ Hybridization; D009061:Mouth Mucosa / Q000821:virology; D015345:Oligonucleotide Probes; D027383:Papillomaviridae / Q000145:classification / Q000302:isolation & purification*; D030361:Papillomavirus Infections / Q000175:diagnosis; D010510:Periodontal Diseases / Q000821:virology; D016133:Polymerase Chain Reaction
chemical_list: D004279:DNA, Viral; D015345:Oligonucleotide Probes