title: Hepatitis C virus infection of salivary gland epithelial cells. Lack of evidence.
abstract: BACKGROUND
  Hepatitis C virus genome (HCV-RNA) has been detected in whole salivary gland tissue of chronically infected patients. However, contamination of the tissue by plasma or blood cells was not excluded by the previous reports.
  
  
  OBJECTIVE
  To assess whether HCV infects the salivary gland epithelial cells in patients with chronic HCV liver disease.
  
  
  METHODS
  Twenty unselected patients with chronic active hepatitis (11 cases) or active cirrhosis (nine cases) were examined. Serum and saliva samples were obtained from all patients, 12 of whom (seven, chronic active hepatitis; five, active cirrhosis) underwent salivary gland biopsy. PCR for HCV-RNA was performed on RNA extracted from serum, saliva and salivary gland epithelial cells collected by isokinetic gradient separation after trypsin digestion of whole salivary gland tissue. Saliva samples were also examined for the presence of secretory IgA anti-HCV by gel chromatography and ELISA testing.
  
  
  RESULTS
  HCV-RNA was detected in all sera with titers ranging from 5.42 x 10(5) genome equivalents/ml to 123.2 x 10(5) genome equivalents/ml. Thirteen patients were infected with genotype 1b, four patients had genotype 1a, two patients had genotype 2a and one patient was unclassifiable. Low titer HCV-RNA (<2 x 10(5) genome equivalents/ml) was detected in 3/20 saliva samples (15%) from highly viremic patients infected with 1b genotype. RNA extracted from salivary gland epithelial cells consistently tested negative for HCV-RNA. In addition, all saliva specimens tested negative for secretory-IgA (S-IgA) anti-HCV, even after a 10-fold concentration of the samples.
  
  
  CONCLUSIONS
  There was no evidence that HCV infects the salivary gland epithelial cells in our viremic patients with HCV chronic liver disease. Low level HCV-RNA in saliva is most probably due to virus spillover from blood.
authors.affiliation: Department of Infectious and Tropical Diseases, La Sapienza University, Rome, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Taliani
authors.forename: D
authors.initials: D
authors.lastname: Celestino
authors.forename: M C
authors.initials: MC
authors.lastname: Badolato
authors.forename: A
authors.initials: A
authors.lastname: Pennica
authors.forename: A
authors.initials: A
authors.lastname: Bozza
authors.forename: G
authors.initials: G
authors.lastname: Poliandri
authors.forename: V
authors.initials: V
authors.lastname: Riccieri
authors.forename: G
authors.initials: G
authors.lastname: Benfari
authors.forename: A
authors.initials: A
authors.lastname: Sebastiani
authors.forename: C
authors.initials: C
authors.lastname: De Bac
authors.forename: G
authors.initials: G
authors.lastname: Quaranta
authors.forename: A
authors.initials: A
authors.lastname: Aceti
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D002850:Chromatography, Gel; D004797:Enzyme-Linked Immunosorbent Assay; D004848:Epithelium / Q000473:pathology / Q000821:virology; D005260:Female; D016679:Genome, Viral; D005838:Genotype; D016174:Hepacivirus / Q000235:genetics / Q000302:isolation & purification*; D006526:Hepatitis C / Q000473:pathology* / Q000821:virology; D006801:Humans; D008103:Liver Cirrhosis / Q000209:etiology / Q000473:pathology / Q000821:virology; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012367:RNA, Viral / Q000097:blood; D012469:Salivary Glands / Q000473:pathology / Q000821:virology*; D014766:Viremia / Q000473:pathology / Q000821:virology
chemical_list: D012367:RNA, Viral