title: [Detection of TTV DNA in liver tissues of patients with non A-G hepatitis by in situ hybridization].
abstract: OBJECTIVE
  To demonstrate the existence of TT virus(transfusion-transmitted virus, TTV) in liver tissues of patients with unknown etiology.
  
  
  METHODS
  Paraffin-embedded liver tissues from 51 cases who were non A-E hepatitis serologically and immunohistochemically negative for HBsAg, HCV NS3 antigen and HGV NS5 antigen were tested by in situ hybridization with Dig TTV DNA probe.
  
  
  RESULTS
  The total positive rate of TTV DNA was 27.5% (14/51). Among the different pathological types, the positive rates were 30.8% (4/13) in acute mild hepatitis, 12.5% (1/8) in acute fulminante hepatitis, 42.9% (3/7) in subacute fulminante hepatitis, 33.3% (2/6) in chronic hepatitis, 22.2% (2/9) in active liver cirrhosis, 25% (1/4) in chronic fulminante hepatitis and 25% (1/4) in primary liver carcinoma respectively. Hybridization signals were detected within the nuclei or cytoplasm of the hepatocyte and most of them in nuclei. The positive cells were diffusely scattered in the intralobular areas in acute hepatitis and aggregated in periportal areas in chronic hepatitis or in the form of clustering in pseudolobules in active liver cirrhosis.
  
  
  CONCLUSIONS
  Our results suggest that the TTV detected from liver tissues or sera from patients with unknown etiology is a novel virus, which belongs to hepadnavirus.
authors.affiliation: Beijing Youan Hospital, Beijing 100054, China.
authors.forename: Z
authors.initials: Z
authors.lastname: Lang
authors.forename: Y
authors.initials: Y
authors.lastname: Zhou
authors.forename: H
authors.initials: H
authors.lastname: Yan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D004266:DNA Virus Infections / Q000821:virology*; D004279:DNA, Viral / Q000032:analysis*; D005260:Female; D006525:Hepatitis, Viral, Human / Q000821:virology*; D006801:Humans; D017403:In Situ Hybridization; D008099:Liver / Q000821:virology*; D008297:Male; D008875:Middle Aged; D022783:Torque teno virus / Q000235:genetics / Q000302:isolation & purification*
chemical_list: D004279:DNA, Viral