Tenascin-C in Chronic Canine Hepatitis: Immunohistochemical Localization and Correlation with Necro-inflammatory Activity, Fibrotic Stage, α-SMA, CK7 and CD3+ Cells
Getnet A. Mekonnen; IJzer Jooske; Hubertus Nederbragt
During fibrosis the extracellular matrix (ECM) is continuously being remodeled and increases in volume due to the production of various proteins. In dogs we studied the distribution of Tenascin-C (TN-C). Also, the correlation of TN-C with the necro-inflammatory activity, α-SMA, CK7 and CD3+ T-lymphocytes was analyzed by using a semi-quantitative scoring system. Three groups (n=19) of dogs were used: group-1 (n=5) with neonatal hepatitis/lobular dissecting hepatitis (NH/LDH), group-2 (n=8) with chronic hepatitis/cirrhosis (CH/CIRR) and group-3 (n=6) of healthy animals.
In the normal livers TN-C was localized mainly in the Disse's space and around the walls of bile ducts and blood vessels. In CH/CIRR livers TN-C was localized at the rim of the regenerating nodules and conspicuous in the bridging fibrous bands. In the NH/LDH, however, TN-C was diffusely distributed along with the reticular fibers that dissect single cells or groups of hepatocytes. α-SMA in the normal hepatic parenchyma showed a slightly irregular signal distributed along the perisinusoidal linings. However, in other groups, α-SMA was increased in fibrotic septa and perisinusoidal linings. CK7 in normal livers was positive in bile ducts. In other groups, however, CK7+ cells were conspicuous in the portal-parenchymal interface, rim of the regenerative nodules and in the degenerated parenchyma. The pattern and distributions of CD3 + lymphocytes were found to oppose that of TN-C. The present result also showed that TN- C is strongly correlated with increased fibrotic stage, inflammatory activity, bile duct proliferation and α-SMA indicating its role in the progression of hepatic fibrosis.