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Bile Duct Damage (bile + duct_damage)
Selected AbstractsPrimary biliary cirrhosis: an orchestrated immune response against epithelial cellsIMMUNOLOGICAL REVIEWS, Issue 1 2000M. Eric Gershwin Summary: Primary biliary cirrhosis (PBC) is an organ-specific autoimmune disease that predominantly affects women and is characterized by chronic progressive destruction of small intrahepatic bile ducts with portal inflammation and ultimately fibrosis. The serologic hallmark of PBC is the presence of antibodies to mitochondria, especially to the E2 component of the pyruvate dehydrogenase complex. The mechanisms by which (and if) such antibodies produce liver tissue injury are unknown. However, the presence of these antibodies has allowed detailed immunological definition of the antigenic epitopes, the nature of reactive autoantibodies and the characterization of T-cell responses. Several mechanisms may now be proposed regarding the immune-mediated bile duct damage in PBC, including the possible role of T-cell-mediated cytotoxicity and intracellular interaction between the IgA class of antimitochondrial antibodies and mitochondrial autoantigens. There are major questions which remain unanswered, including, of course, etiology, but also the reasons for female predominance, the absence of PBC in children, the relative ineffectiveness of immunosuppressive drugs, and the specific role of mitochondrial antigens. The data so far provide suggestive evidence that PBC is a mucosal disease; this thesis provides a basis for discussion of etiology via the enterohepatic circulation of toxins and/or infection. [source] Tumor necrosis factor-, and interferon-, directly impair epithelial barrier function in cultured mouse cholangiocytesLIVER INTERNATIONAL, Issue 1 2003Hanada Shinichiro Abstract:Background/Aims: In primary biliary cirrhosis (PBC), cytokines from CD4 + T lymphocytes were suggested to contribute to the intralobular bile duct damage together with cellular immunity by CD8 + T lymphocytes. Recently, we reported that immunolocalization of 7H6 , a tight junction (TJ)-associated protein , was significantly diminished in cholangiocytes in the PBC liver. In this study, we examined the direct effects of several cytokines , tumor necrosis factor-, (TNF-,), interferon-, (IFN-,), interleukin-2 and 4 (IL-2 and 4) , on TJ in immortalized mouse cholangiocytes. Moreover, we examined the inhibitory effect of ursodeoxycholic acid (UDCA)on cytokine-induced changes in paracellular permeability. Methods: Barrier function of TJ was evaluated by measuring transepithelial electrical resistance (TER) and 3H-inulin flux. We also performed immunostaining and immunoblotting for TJ-associated proteins , claudin-1 and -3, occludin, zonula occluden-1 (ZO-1) and 7H6. Results: TNF-, and IFN-,, but neither IL-2 nor IL-4, significantly decreased TER (P < 0.005). 3H-inulin flux studies confirmed IFN-,-induced increases in paracellular permeability of cholangiocytes (P < 0.001). In immunostaining and immunoblotting studies, TJ-associated proteins were well preserved in TNF-,- or IFN-,-treated cells. Ursodeoxycholic acidhas been found to have no inhibitory effect on increased paracellular permeability induced by TNF-, or IFN-,. Conclusion: These findings show that TNF-, and IFN-, disrupt barrier function of TJ in cholangiocytes without major structural changes to TJ and suggest that disruption of TJ function and subsequent leakage of the bile constituents may influence the aggravation of cholestasis in PBC. [source] Cholestatic syndrome with bile duct damage and loss in renal transplant recipients with HCV infectionLIVER INTERNATIONAL, Issue 2 2001Johanna K. Delladetsima Abstract:Background/Aims: Bile duct cells are known to be susceptible to hepatitis B and C virus, while it has been recently suggested that hepatitis B virus (HBV) and hepatitis C virus (HCV) infection may have a direct role in the pathogenesis of vanishing bile duct syndrome (VBDS) after liver transplantation. We report the development of a cholestatic syndrome associated with bile duct damage and loss in four HCV-infected renal transplant recipients. Methods: All four patients were followed up biochemically, serologically and with consecutive liver biopsies. Serum HCV RNA was quantitatively assessed and genotyping was performed. Results: Three patients were anti-HCV negative and one was anti-HCV/HBsAg positive at the time of transplantation and received the combination of methylprednisolone, azathioprine and cyclosporine A. Two patients became anti-HCV positive 1 year and one patient 3 years post-transplantation. Elevation of the cholestatic enzymes appeared simultaneously with seroconversion, or 2,4 years later, and was related to lesions of the small-sized interlobular bile ducts. Early bile duct lesions were characterized by degenerative changes of the epithelium. Late and more severe bile duct damage was associated with bile duct loss. The progression of the cholestatic syndrome coincided with high HCV RNA serum levels, while HCV genotype was 1a and 1b. Two patients (one with HBV co-infection) developed progressive VBDS and died of liver failure 2 and 3 years after biochemical onset. One patient, despite developing VBDS within a 10-month period, showed marked improvement of liver function after cessation of immunosuppression because of graft loss. The fourth patient, who had mild biochemical and histological bile duct changes, almost normalized liver function tests after withdrawal of azathioprine. Conclusion:Á progressive cholestatic syndrome due to bile duct damage and loss may develop in renal transplant patients with HCV infection. The occurrence of the lesions after the appearance of anti-HCV antibodies and the high HCV RNA levels are indicative of viral involvement in the pathogenesis. Withdrawal of immunosuppressive therapy may have a beneficial effect on the outcome of the disease. [source] Recurrent primary biliary cirrhosisLIVER TRANSPLANTATION, Issue 6 2003James Neuberger Liver transplantation remains the only effective treatment for end-stage primary biliary cirrhosis (PBC). It appears now well accepted that the disease recurs in the allograft. The diagnosis of recurrent PBC is made on the basis of a consistent history and demonstrating the histologic features of PBC on liver biopsy and exclusion of other causes of bile duct damage [source] Osteopontin is involved in the formation of epithelioid granuloma and bile duct injury in primary biliary cirrhosisPATHOLOGY INTERNATIONAL, Issue 1 2003Kenichi Harada Recently, it was shown that osteopontin (OPN) is involved as a chemoattractant cytokine in the recruitment of macrophages and T lymphocytes in the granulomas of diverse etiologies and also plays an important role in the production of autoantibodies and development of autoimmune diseases. Primary biliary cirrhosis (PBC) is characterized by immune-mediated bile duct damage with frequent epithelioid granulomas. In this study, the expression of OPN was immunohistochemically examined in 25 PBC and 52 control livers. Epithelioid cells within granuloma in PBC expressed OPN variably. These cells were also positive for CD68, suggesting their histiocyte/macrophage lineage. In addition, strong expression of OPN was seen in the cytoplasm of mononuclear cells infiltrating around granulomas and also damaged bile ducts in PBC. The number of such positive mononuclear cells and the ratio of OPN-positive cells/total infiltrating cells in portal tracts were higher in PBC than in controls. The majority of these OPN-positive cells were found to be IgG- or IgM-producing plasma cells. These suggest that in PBC, OPN is an important immune molecule in portal tracts, and contributes to the recruitment of mononuclear cells into epithelioid granuloma and also participates in bile duct injury via B-cell differentiation and plasma cell expansion. [source] Hepatitic pattern of graft versus host disease in childrenPEDIATRIC BLOOD & CANCER, Issue 5 2007Héctor Melín-Aldana MD Abstract Background Liver involvement by graft-versus-host disease (GVHD) is characterized histologically by bile duct damage, which may be severe. A different pattern, "hepatitic GVHD," has been described in adult patients. This pattern also shows marked lobular hepatitis and hepatocellular damage. We report the development of hepatitic GVHD in six pediatric patients. Procedure Clinical information and histologic features of liver biopsy samples were retrospectively reviewed. Results Patients' ages ranged from 3 to 11 years. Underlying diagnosis, pre-transplant conditioning and GVHD prophylaxis varied. Peripheral blood stem cells were the source of the allograft in four patients, matched sibling in one, and matched-unrelated donor in one. Hepatic GVHD was detected between 149 and 310 days post-transplant. Prior acute GVHD had developed in two patients, and involved the skin and/or gastrointestinal tract. No patients had significant ductopenia. Only one patient had significant lymphocytic infiltration of bile ducts (ductitis). Bile duct epithelial damage and significant portal/periportal inflammation were present in all patients. Lobular necro-inflammation was present in five patients. Five patients improved with immunosuppression and one died with progressive GVHD. Conclusions This series focuses on hepatitic GVHD in pediatric patients. Clinical and histologic patterns are similar to what has been described in adults. Specific etiology and pathogenesis of this entity remain unclear. Pediatr Blood Cancer 2007;49:727,730. © 2006 Wiley-Liss, Inc. [source] | ||||||||||