HISTOLOGICAL AND IMMUNOHISTOCHEMICAL STUDY OF HEPATIC STELLATE CELLS PRE AND POST-TRANSPLANTED HUMAN LIVER

Abstract

Background: Hepatic stellate cells (HSCs) regulate vitamin A metabolism and play a vital role during the activation of the immune response. During liver damage, HSCs transform to myofibroblast-like cells, leading to loss of their lipid content and synthesis of extracellular matrix (ECM) inducing liver fibrosis. Objective: The present study aimed to establish the correlation between HSCs activity within different areas of hepatic tissue and the degree of liver fibrosis in individuals with normal liver, hepatitis C virus infected patients and post-transplanted liver. Patients and methods: The study involved thirty four cases from the international medical center classified into three groups: group 1 included ten healthy individuals as control, group 2 included twelve patients with chronic hepatitis C virus and liver cirrhosis and group 3 included twelve patients with post-transplanted liver due to liver previous hepatitis C virus infection and hepatic cirrhosis subdivided into group 3a five patients who received antihepatitis C treatment, and group 3b seven patients who didn’t receive antihepatitis C treatment. We used H&E and Masson trichrome stains, immunohistochemical detection of a-smooth muscle actin (a-SMA), Glial Fibrillary acidic protein (GFAP) and transmission electron microscopy (TEM). Results: H&E stain revealed hepatic tissue with preserved architecture in group 1, disrupted architecture and areas of feathery degeneration in group 2, normal tissue histology in group 3a and moderate cellular infiltration in group 3b. Masson trichrome stain revealed normal collagen fibers distribution in group1, advanced fibrosis in group 2, no fibrotic changes in group 3a and few foci of bridging fibrosis in group 3b. Immunohistochemical analysis revealed increased expression of α-SMA in group 2 and group 3b in comparison to group 1 and group 3a. Immunohistochemical analysis revealed increased expression of GFAP in group 3b in comparison to group 3a, group 2 and group 1. TEM showed increase in the fibrous tissue and degeneration in the ultrastructure of the hepatocyte with few lipid droplets in HSCs of group 2 compared to group 1. Conclusion: The hepatic stellate cells play an important role in the fibrosis of the liver damaged by hepatitis C virus and in the post-transplanted liver which not treated from HCV.