High frequency of Human Cytomegalovirus DNA in the Liver of Infants with Extrahepatic Neonatal Cholestasis

BACKGROUND: Biliary atresia (BA) is the most severe hepatic disorder in newborns and its etiopathogenesis remains unknown. Viral involvement has been proposed, including the human cytomegalovirus (HCMV). The aims of the study were to use the polymerase chain reaction (PCR) to screen the liver tissue of infants with extrahepatic cholestasis for HCMV and to correlate the results with serological antibodies against HCMV and histological findings. METHODS: A retrospective study in a tertiary care setting included 35 patients (31 BA, 1 BA associated with a choledochal cyst, 2 congenital stenosis of the distal common bile duct and 1 hepatic cyst). HCMV serology was determined by ELISA. Liver and porta hepatis were examined histologically. Liver samples from infants and a control group were screened for HCMV DNA. RESULTS: Twelve patients had HCMV negative serology, 9 were positive for IgG antibodies and 14 were positive for IgG and IgM. Nine liver and seven porta hepatis samples were positive for HCMV DNA but none of the control group were positive (general frequency of positivity was 34.3% – 12/35). There was no correlation between HCMV positivity by PCR and the histological findings. The accuracy of serology for detecting HCMV antibodies was low. CONCLUSION: These results indicate an elevated frequency of HCMV in pediatric patients with extrahepatic neonatal cholestasis. They also show the low accuracy of serological tests for detecting active HCMV infection and the lack of correlation between HCMV positivity by PCR and the histopathological changes

Human liver sinusoidal endothelial cells induce apoptosis in activated T cells: a role in tolerance induction

BACKGROUND: The liver may have a role in peripheral tolerance, by serving as a site for trapping, apoptosis and phagocytosis of activated T cells. It is not known which hepatic cells are involved in these processes. It was hypothesised that liver sinusoidal endothelial cells (LSEC) which are strategically placed for participation in the regulation of sinusoidal blood flow, and express markers involved in recognition, sequestration and apoptosis, may contribute to peripheral tolerance by inducing apoptosis of activated T cells. METHODS: By using immunoassays and western blot analysis, the fate of activated T cells when incubated with human LSEC isolated from normal healthy livers was investigated. RESULTS: Evidence that activated (approximately 30%) but not non‐activated T cells undergo apoptosis on incubation with human LSEC in mixed cell cultures is provided. No difference in the results was observed when unstimulated and cytokine‐stimulated LSEC were used. T cell–LSEC contact is required for induction of apoptosis. Apoptosis induced by LSEC was associated with caspase 8 and 3 activity and strong expression of the proapoptotic molecule Bak. Transforming growth factor β (TGFβ) produced constitutively by LSEC is partly responsible for the caspase‐induced apoptosis, as neutralising antibodies to TGFβ markedly attenuated apoptosis, up regulated the antiapoptotic molecule Bcl‐2 and partially blocked caspase‐3 activity. CONCLUSION: These findings broaden the potential role of LSEC in immune tolerance and homeostasis of the immune system. This study may provide insight for exploring the mechanisms of immune tolerance by liver allografts, immune escape by some liver pathogens including hepatitis C and pathogenesis of liver diseases

Reduction in serum levels of antimitochondrial (M2) antibodies following immunoglobulin therapy in severe combined immunodeficient (SCID) mice reconstituted with lymphocytes from patients with primary biliary cirrhosis (PBC)

The effect of gammaglobulin treatment on autoantibody production was investigated in SCID mice reconstituted with human peripheral blood mononuclear cells (PBMC) obtained from patients with PBC. All reconstituted mice displayed the presence of human antimitochondrial antibodies (αM2Ab) of both IgG and IgM types before treatment with human immunoglobulin. Two weeks after i.p. injection of 20 ×106 PBMC into SCID mice, i.p. treatment with various preparations of human immunoglobulin was initiated. In control animals treated with saline, serum levels of human αM2Ab of the IgG type increased with time, peaking around 4 weeks after reconstitution. In contrast, human IgG autoantibodies rapidly decreased in all animals treated with human IgG. Treatment with a human IgM preparation had no effect on serum levels of αM2Ab of the IgG type. The results may suggest that the pronounced reduction of specific IgG autoantibodies was due to an increased catabolism of human IgG, including the autoantibodies, in the gammaglobulin-treated mice. Although the production of human αM2Ab in reconstituted mice could be easily shown, PBC-specific liver lesions or bile duct destruction were not observed, irrespective of treatment protocol

The risk of liver and bile duct cancer in patients with chronic viral hepatitis, alcoholism, or cirrhosis.

No prospective study has analyzed simultaneously chronic viral hepatitis and alcoholism as risk factors for liver carcinogenesis, while taking into consideration the role of cirrhosis. Nor has the risk for hepatocellular carcinoma among patients with chronic viral hepatitis been prospectively evaluated in a low-risk Western population. Last, the relationship between hepatocellular carcinoma risk factors and bile duct cancer remains to be clarified. We analyzed prospectively the risk for primary liver and extrahepatic biliary tract cancer among 186,395 patients hospitalized with either chronic viral hepatitis, alcoholism, cirrhosis, or any combination of these conditions through linkages between national Swedish registers. Compared with the general population, the relative risk of hepatocellular carcinoma was 34.4 for chronic viral hepatitis alone, 2.4 for alcoholism alone, and 40.7 for cirrhosis alone. Among patients with combinations of these risk conditions, the relative risk of hepatocellular carcinoma was 27.3 for chronic viral hepatitis and alcoholism, 118.5 for chronic viral hepatitis and cirrhosis, 22.4 for alcoholism and cirrhosis, and 171.4 for all 3 conditions. We found limited evidence for an excess risk of intrahepatic, but not for extrahepatic, biliary duct cancer. Cirrhosis amplifies the risk of hepatocellular carcinoma among patients with chronic viral hepatitis, but it is not a prerequisite for liver carcinogenesis. In contrast, cirrhosis may be a necessary intermediate for the development of hepatocellular carcinoma among alcoholics

Cholangiocarcinoma in primary sclerosing cholangitis: risk factors and clinical presentation.

BACKGROUND: Primary sclerosing cholangitis (PSC) confers a high risk of cholangiocarcinoma (CC) development. Since patients at risk of CC may be selected for early liver transplantation, it is a challenge to identify any predisposing factors. We compared the presentation and natural history of a large number of PSC patients with and without later CC development to identify features associated with risk of CC. METHODS: Clinical and laboratory data from presentation and follow-up were collected from 394 PSC patients from five European countries. The cohort included 48 (12.2%) patients with CC. RESULTS: CC was diagnosed within the first year after diagnosis of PSC in 24 (50%) cases and in 13 (27%) patients at intended liver transplantation. Jaundice, pruritus, abdominal pain and fatigue were significantly more frequent at diagnosis of PSC in the group that developed CC, but not after exclusion of cases diagnosed within the first year. Inflammatory bowel disease was diagnosed at least 1 year before PSC more often among patients with CC development than among those without (90% and 65%, respectively: P = 0.001). The duration of inflammatory bowel disease before diagnosis of PSC was significantly longer in patients who developed CC than in the remaining group (17.4 years and 9.0 years, respectively: P=0.009 in multivariate analysis). CONCLUSIONS: A high proportion of CC cases is diagnosed within the first year after diagnosis of PSC. A long history of inflammatory bowel disease is a risk factor for CC development

The HLA-DR3,DQ2 heterozygous genotype is associated with an accelerated progression of primary sclerosing cholangitis.

BACKGROUND: An improvement of prognostic models in primary sclerosing cholangitis (PSC) is needed. In particular, inclusion of prognostic markers that are independent of the disease stage would be advantageous. We investigated whether HLA class II genes associated with PSC are also related to disease progression. METHODS: The study included 265 PSC patients from five European countries with a median follow-up of 9.1 years. The end-points were death (n = 38) or liver transplantation (n = 52). Thirty patients developed cholangiocarcinoma during follow-up. RESULTS: The DRB1*03,DQA1*0501, DQB1*02 (i.e. DR3,DQ2) heterozygous genotype was associated with an increased risk of death or liver transplantation (hazard ratio = 1.63; 95% confidence interval (CI) = 1.06-2.52). The presence of a DQ6 encoding haplotype (DQB1*0603 or DQB1*0602) in DR3,DQ2 negative individuals was associated with a reduced risk of death or liver transplantation (hazard ratio = 0.57; 95% CI = 0.36-0.88). There was a trend towards an increased risk of developing cholangiocarcinoma among DR4,DQ8 positive patients, but this did not reach significance (odds ratio = 2.27; 95% CI = 0.78-6.62). CONCLUSION: The DR3,DQ2 heterozygous genotype is associated with a more rapid progression of PSC, whereas HLA-DQ6 is associated with a retarded disease progression. It is possible that the DR4,DQ8 haplotype is related to cholangiocarcinoma development

Time-dependent Cox regression model is superior in prediction of prognosis in primary sclerosing cholangitis.

More precise prognostic models are needed for prediction of survival in patients with primary sclerosing cholangitis (PSC), particularly for the selection of candidates for liver transplantation. The aim of this study was to develop a time-dependent prognostic model for the calculation of updated short-term survival probability in PSC. Consecutive clinical and laboratory follow-up data from the time of diagnosis were collected from the files of 330 PSC patients from 5 European centers, followed for a median of 8.4 years since diagnosis. Time-fixed and time-dependent Cox regression analyses, as well as the additive regression model, were applied. The reliability of the models was tested by a cross-validation procedure. Bilirubin (on a logarithmic scale), albumin, and age at diagnosis of PSC were identified as independent prognostic factors in multivariate analysis of both the time-fixed and the time-dependent Cox regression models. The importance of bilirubin was more pronounced in the time-dependent model (hazard ratio [HR], 2.84) than in the time-fixed analysis (hazard ratio, 1.51). The additive regression model indicated that once the patients survive beyond the first 5 years, the impact on prognosis of albumin at diagnosis ceases. The time-dependent prognostic model was superior to the time-fixed variant in assigning low 1-year survival probabilities to patients that actually survived less than 1 year. In conclusion, a time-dependent Cox regression model has the potential to estimate a more precise short-term prognosis in PSC compared with the traditional time-fixed models