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Transforming growth factor-beta (TGF-beta) system is involved in the control of cell growth and extracellular matrix formation. Previous studies in patients with chronic liver disease have shown that increased TGF-beta expression significantly correlates with the degree of hepatic fibrosis. The aim of our study was to define TGF-beta system expression in hepatic parenchymal cells and its significance in patients with differing extents of chronic liver disease of viral etiology. Expression of TGF-beta 1, TGF-beta 1 type II receptor (TGF-beta RII) and the Smad signaling pathway was evaluated in consecutive liver sections of 77 patients with chronic liver disease (65 HCV positive and 12 HBV positive). Results were correlated with histological scores and apoptotic activity. TGF-beta 1 was demonstrated in the liver of 30/56 (53.6%) patients with chronic hepatitis and 20/21 (95%) patients with cirrhosis, but in none of the 20 normal livers. Positive cytokine reaction was seen both in stromal cells and hepatocytes. Expression of TGF-beta RII and Smad proteins showed a distribution pattern similar to that of TGF-beta, with a direct correlation in terms of immunoreactivity extent. A significant correlation was found between parenchymal expression of TGF-beta system and inflammatory and fibrosis scores. No correlation was found with apoptotic index and other morphological, clinical or virological parameters. The TGF-beta system is up-regulated at the ligand, receptor and signaling level in the liver of patients with more active disease. The strong expression of TGF-beta and the Smad pathway in parenchymal cells suggests that hepatocytes, in addition to mesenchymal cells, may play an important role in the progression of liver disease. [ABSTRACT FROM AUTHOR]

ABSTRACT- Antibodies against thymus epithelial cells (anti-TEC) and the basal cell layer (BCLA) of squamous epithelia have been described in association with HDV-related chronic liver disease (CLD). Data are lacking on their presence during nAnB virus infection. Sera from 51 patients with nAnB post-transfusion hepatitis, including acute and chronic cases diagnosed during a prospective study on candidates for cardiac surgery, and 167 with various forms of CLD were tested for the presence of anti-TEC and BCLA using indirect immunofluorescence on human thymus and rat forestomach sections. Both antibodies mainly occurred in nAnB, HDV and cryptogenic CLD (anti-TEC: 51%, 47% and 42%; BCLA: 29%, 38% and 31%, respectively). The prevalence of anti-TEC in nAnB CLD turned out to be higher than that recorded in alcoholic, HBV-related, autoimmune, liver and kidney microsomal antibody positive CLD and primary biliary cirrhosis (p ranging from < 0.03 to < 0.0004). Two monoclonal antibodies (Mabs) to cytokeratins gave a pattern superimposable on that of spontaneous anti-TEC (both Mabs) and BCLA (only one). Antibodies against epithelial constituents, presumably targeting cytokeratin-associated antigens, occur not only in HDV CLD, as previously reported, but also in nAnB CLD, where they might represent a diagnostic aid, due to the unavailability of reliable serological markers of nAnB infection. The close similarity of anti-TEC and BCLA status between nAnB and cryptogenic CLD suggests a nAnB etiology of at least a proportion of chronic liver patients at present scored as cryptogenic. [ABSTRACT FROM AUTHOR]