Chronic hepatitis C virus (HCV) infection results in progressive liver fibrosis leading to cirrhosis and liver cancer. The mechanism for this remains unclear but hepatocyte apoptosis is thought to play a major role. Hepatocyte apoptosis in human liver tissue was determined by immunohistochemistry for cytokeratin 18 (M30 CytoDEATH) and cleaved poly(ADP-ribose) polymerase (PARP). In vitro studies were performed with replication-defective recombinant adenoviruses expressing HCV proteins (rAdHCV) to study the effects of HCV on cell death in Huh7 cells, primary mouse hepatocytes (PMoHs) and primary human hepatocytes (PHHs). Cell viability and apoptosis were studied using crystal violet assays and Western blots probed for cleaved caspase-3 and cleaved PARP, with and without treatment with the pan-caspase inhibitor Q-VD-OPh and necrostatin-1. Liver tissue of HCV-infected patients expressed elevated levels of apoptotic markers compared with HCV-negative patients. rAdHCV infection reduced cell viability compared with uninfected controls and cells infected with control virus (rAdGFP). Huh7, PMoHs and PHHs infected with rAdHCV showed significantly increased levels of apoptotic markers compared with uninfected controls and rAdGFP-infected cells. In rAdHCV-infected Huh7, treatment with Q-VD-OPh and necrostatin-1 both improved cell viability. Q-VD-Oph also reduced cleaved PARP in rAdHCV-infected Huh7 and PMoHs. Hepatocyte apoptosis is known to be increased in the livers of HCV-infected patients. HCV promoted cell death in primary and immortalized hepatocytes, and this was inhibited by Q-VD-OPh and necrostatin-1. These findings indicate that HCV-induced cell death occurs by both apoptosis and necroptosis, and provide new insights into the mechanisms of HCV-induced liver injury.

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Endoscopic variceal ligation (EVL) is widely used to prevent esophageal variceal bleeding in patients with advanced cirrhosis. However, the safety and efficacy of EVL in this setting have not been clearly established. This study included 300 adult patients with cirrhosis on our liver transplant waitlist who underwent upper gastrointestinal endoscopy. Esophageal varices deemed to be at high risk of bleeding were banded until eradication or transplantation. A retrospective review of patient notes and endoscopy databases was undertaken, and the number of banding episodes, complications, and patient outcomes were recorded. Forty-two of 300 patients presented with or had previous variceal bleeding prior to referral and were excluded from the analysis. Of the remaining 258 patients, 101 underwent a total of 259 banding episodes (2.6 per patient) with a median follow-up post-banding of 18.4 months per patient (a total of 150 patient years). Failed prophylaxis occurred in 2 patients (2%), and there were 3 episodes (1.2%) of acute hematemesis from band-induced ulceration. One patient (1%) had mild esophageal stricturing post-banding without dysphagia. Four of 36 patients (11%) previously found to have moderately sized or larger varices that were not banded presented with hematemesis due to variceal bleeding and were subsequently banded. None of the patients that received banding died because of bleeding or failed to receive a transplant as a result of banding complications. This study shows that in liver transplant candidates, EVL is highly effective in preventing first variceal bleed. Although banding carries a small risk of band-induced bleeding, this rate is low in comparison with the predicted rate of variceal bleeding in this population. Liver Transpl 15:1508Transpl 15: -1513Transpl 15: , 2009

IntroductionImmunosuppressants are used ubiquitously post-liver transplantation to prevent allograft rejection. However their effects on hepatocytes are unknown. Experimental data from non-liver cells indicate that immunosuppressants may promote cell death thereby driving an inflammatory response that promotes fibrosis and raises concerns that a similar effect may occur within the liver. We evaluated apoptosis within the liver tissue of post-liver transplant patients and correlated these findings with in vitro experiments investigating the effects of immunosuppressants on apoptosis in primary hepatocytes.MethodsHepatocyte apoptosis was assessed using immunohistochemistry for M30 CytoDEATH and cleaved PARP in human liver tissue. Primary mouse hepatocytes were treated with various combinations of cyclosporine, tacrolimus, sirolimus, or MMF. Cell viability and apoptosis were evaluated using crystal violet assays and Western immunoblots probed for cleaved PARP and cleaved caspase 3.ResultsPost-liver transplant patients had a 4.9-fold and 1.7-fold increase in M30 CytoDEATH and cleaved PARP compared to normal subjects. Cyclosporine and tacrolimus at therapeutic concentrations did not affect hepatocyte apoptosis, however when they were combined with MMF, cell death was significantly enhanced. Cell viability was reduced by 46% and 41%, cleaved PARP was increased 2.6-fold and 2.2-fold, and cleaved caspase 3 increased 2.2-fold and 1.8-fold following treatment with Cyclosporine/MMF and Tacrolimus/MMF respectively. By contrast, the sirolimus/MMF combination did not significantly reduce hepatocyte viability or promote apoptosis.ConclusionCommonly used immunosuppressive drug regimens employed after liver transplantation enhance hepatocyte cell death and may thus contribute to the increased liver fibrosis that occurs in a proportion of liver transplant recipients.