Peripheral blood serum markers for apoptosis and liver fibrosis: are they trustworthy indicators of liver realness?

BACKGROUND/AIMS: No reliable serum markers for liver inflammation, apoptosis and fibrosis have been established yet, although a large number have been evaluated. Moreover, it is not clear if a molecule detected and quantified in peripheral vein blood is a really trustworthy marker of the liver condition. To answer to this question, we had the opportunity to study paired serum samples drawn simultaneously during haemodynamic study from the right hepatic vein and from a peripheral vein from patients with hepatitis C virus related cirrhosis. METHODS: The serum levels of transforming growth factor beta-1, tumour necrosis factor-alpha, hyaluronic acid, soluble (s)human leukocyte class I antigens, soluble FAS ligand, and stumour necrosis factor related ligand were assessed in a consecutive series of 15 patients with hepatitis C virus related cirrhosis. RESULTS: No statistically significant differences were found between hepatic vein and peripheral vein levels for the cytokines, substance or soluble molecules evaluated, excepted for shuman leukocyte class I antigens. Instead a strong correlation between hepatic vein and peripheral vein levels was present for: hepatic vein, shuman leukocyte class I antigens, tumour necrosis factor-alpha, soluble FAS ligand and stumour necrosis factor related ligand, but not for transforming growth factor beta-1. CONCLUSIONS: Our results show that peripheral vein measurements seem to reflect the liver compartment in a large majority of cases, but not for all molecules and probably for any liver diseases. Further studies on this line are warranted in particular for new molecules.

Soluble apoptosis molecules in primary biliary cirrhosis: analysis and commitment of the Fas and tumour necrosis factor-related apoptosis-inducing ligand systems in comparison with chronic hepatitis C.

Apoptosis in the liver is generated mainly by the Fas system. Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) has been proposed recently as a new apoptotic inducer. In the liver environment hepatocytes and biliary epithelial cells express TRAIL receptors which are up-regulated by increased levels of bile acids and during viral hepatitis. As for FasL, a soluble form of TRAIL has been described. To explore the commitment and level of activation of these two apoptotic systems in patients affected by primary biliary cirrhosis (PBC) or chronic hepatitis C (CH-C), a comparative study was drawn. Thirty patients with PBC on ursodeoxycholic acid have been enrolled. This group was compared with 30 patients with CH-C and with 20 healthy subjects. Soluble Fas ligand (sFasL) and soluble TRAIL (sTRAIL) levels were evaluated by double determinant immune assay and enzyme-linked immunosorbent assay (ELISA), respectively. Soluble FasL molecules were higher in PBC compared to CH-C (P=0 x 009). Soluble FasL was not detected in controls. Soluble TRAIL was significantly higher in CH-C patients compared to PBC (P=0 x 0001). Soluble TRAIL levels were higher in PBC and in CH-C than in controls (P=0 x 015 and P<0 x 001, respectively). No correlation between sFasL and sTRAIL, stage of disease, liver histology in each disease and cytolysis was present. Our data show different levels of commitment of TRAIL and Fas apoptosis-inducing systems in CH-C and PBC. Thus a different prominent role of TRAIL and Fas systems in the pathogenesis of these two conditions can be speculated: the former by inducing the death of infected hepatocytes, the latter by mediating the disappearance of bile duct.

Pegylated interferon and ribavirin in re-treatment of responder-relapser HCV patients.

BACKGROUND: The re-treatment of patients who relapse after a course of standard interferon and ribavirin with pegylated interferon alfa-2b plus ribavirin is an open issue. AIMS: To evaluate efficacy and safety of treatment with pegylated interferon alfa-2b plus ribavirin and the role of early HCV-RNA assessment as a predictor of sustained response. PATIENTS: Between May 2001 and December 2002, 242 consecutive patients with chronic hepatitis C were enrolled in an open, regional, multicentre study. Seventy-eight of them were responder-relapsers to a previous course of combination therapy. METHODS: Patients were treated with pegylated interferon alfa-2b (1 microg/kg/week) plus ribavirin (800-1200 mg daily). Qualitative HCV-RNA was performed at week 2. Genotypes 1-4 were treated for 48 weeks, while genotypes 2 and 3 were treated for 24 weeks. RESULTS: We obtained an overall sustained virological response rate of 41.0% (78.6% for patients with genotypes 2-3). CONCLUSION: This treatment schedule prove to be safe and effective in relapsers with genotype non-1 while genotype 1-4 patients had a low rate of sustained virological response. Qualitative virological assessment after 2 weeks may identify patients who are more likely to reach sustained virological response, but it is not a valid tool for a stopping rule approach.

Serum lamivudine levels in the presence of a lamivudine-resistant HBV mutant.

BACKGROUND/AIMS: Lamivudine efficiently inhibits hepatitis B virus replication and has been used to treat hepatitis B virus recurrence after orthotopic liver transplantation. Although effective, its use is hampered by viral breakthrough due to the appearance of hepatitis B virus drug-resistant strains. Aims of this work were to evaluate the inter- and intra-individual variations of lamivudine serum levels and the effects on the drug levels of the lamivudine-resistant hepatitis B virus mutant infection. METHODS: Serum lamivudine concentration was measured by high-performance liquid chromatography. Polymerase chain reaction analysis and sequencing analysis of the reverse transcriptase area of the polymerase was performed on each sample using specific primers. A polymerase chain reaction-enzyme-linked immunosorbent assay was used to differentiate between wild-type hepatitis B virus and lamivudine-resistant hepatitis B virus strain. RESULTS: Lamivudine serum levels presented minor inter- and intra-individual fluctuations along time, with an important increase at the time of the hepatitis flare-up due to the hepatitis B virus mutant presence. When the wild-type hepatitis B virus briefly reappeared as a mixed population, the titre of lamivudine dropped to below the detection level. CONCLUSIONS: While lamivudine serum levels appears stable when the anti-viral efficacy is fully achieved, important fluctuations are present according to the type of viral population, with a considerable decrease possibly due to the presence of the wild-type virus.

Kinetics of soluble tumour necrosis factor (TNF)-alpha receptors and cytokines in the early phase of treatment for chronic hepatitis C: comparison between interferon (IFN)-alpha alone, IFN-alpha plus amantadine or plus ribavirin.

We have previously studied the effect of three different treatment regimens with interferon (IFN)-alpha alone or in combination with amantadine or ribavirin on viral kinetics in the first month of therapy. To understand the regulation of cytokine immune response during early inhibition of HCV replication, we analysed the longitudinal profile of proinflammatory markers (soluble TNFRs), of type 1 cytokines [IFN-gamma and interleukin (IL-12)], and of a type 2 cytokine (IL-10). Twenty-two chronic hepatitis C patients received daily therapy for 6 months. Sera were collected at baseline, at 6, 12, 24, 30 and 48 h and at the 3rd, 7th, 15th and 30th days of treatment. All cytokines and receptors were evaluated by enzyme linked immunosorbent assay (ELISA). At baseline, a correlation was found between the two soluble TNFRs (P < 0.0001) and between the soluble TNFRs and ALT levels (P < 0.003), as shown previously. Regardless of the type of treatment, lower levels of soluble TNFR-p75 were present from day 3 in patients who had significant virus decay at day 30 (P < 0.01). Baseline IL-10 levels correlated with TNFR-p75 (P < 0.01) and with treatment response (P < 0.05) and a significant IL-10 reduction from baseline was observed from day 3 among responders, irrespective of the type of treatments (P < 0.05). IL-12 and IFN-gamma levels did not differ according to treatment or outcome. These findings suggest a pivotal role for IL-10 in orchestrating the antiviral immune response. Its early decline can favour the shift from a Th2 to a Th1 immune response, which has been shown to be associated with a long-term virological response to treatment.

Argininosuccinate lyase: a new autoantigen in liver disease.

Anti-liver cytosol 1 autoantibody (LC1) characterizes a severe form of autoimmune hepatitis (AIH), staining the cytoplasm of periportal hepatocytes and targeting an unidentified 60-kD liver cytosolic antigen. To identify its target, we used high-titre anti-LCI+ sera from two patients with AIH to screen 18 cytoplasm enzymes with periportal location by double immunodiffusion (DDI). Both sera gave a broad precipitin line against human liver cytosol, suggesting that they may recognize two distinct antigens, a possibility confirmed by the appearance of two precipitin lines when DDI conditions were optimized (0.8% agarose and 3% polyethylene glycol (PEG)). Experiments by DDI and Western blot (WB) identified a liver cytosolic autoantigen of 50 kD, different from LC1, giving a line of identity with argininosuccinate lyase (ASL). Reactivity to ASL was then investigated by DDI and WB in 57 patients with AIH, 17 with primary biliary cirrhosis (PBC), 15 with chronic hepatitis B virus (HBV) infection, 13 with alphal-antitrypsin deficiency, 17 with Wilson's disease, 18 with extrahepatic autoimmune disorders, and in 48 healthy controls. Anti-ASL was found in 16% of AIH and 23% of PBC patients by DDI and in 14% of AIH, 23% of PBC and 20% of HBV patients by WB. No argininosuccinate was present in the urine of four anti-ASL+ patients tested, excluding an inhibition of enzymatic activity by anti-ASL. The addition of anti-ASL+ serum to human fibroblast cultures induced a significant increase in ASL activity. ASL is a new autoantigen in liver disease and its clinical relevance warrants further investigation.

S-adenosil-L-methionine is able to reverse the immunosuppressive effects of chenodeoxycholic acid in vitro.

The study was conceived to evaluate if S-adenosil-L-methionine, a substance commonly used in the treatment of cholestasis in patients with cirrhosis and chronic hepatitis, exerts any immunological effect and of it is able to counterbalance bile acid-mediated immunosuppression. Proliferation and interleukin 2 and interferon-gamma secretion of human lymphocytes, collected from healthy subjects and exposed to mitogenic stimuli (phytohemagglutinin, pokeweed and anti-CD3 monoclonal antibodies), were analysed in the basal condition or after exposure to S-adenosil-L-methionine and/or chenodeoxycholic acid. Chenodeoxycholic acid inhibited phytohemagglutinin-induced lymphocyte proliferation and interferon-gamma secretion, and phytohemagglutinin and pokeweed-mediated interleukin 2 secretion. S-adenosil-L-methionine did not affect lymphocyte proliferation while it reduced interleukin 2 secretion upon phytohemagglutinin and pokeweed stimulation and interferon-gamma secretion upon all stimuli tested. Moreover, S-adenosil-L-methionine counteracted chenodeoxycholic acid-mediated inhibition of lymphocyte proliferation and interleukin 2 secretion. The results of our study confirm the immunosuppressive role of chenodeoxycholic acid on both secretive and proliferative lymphocyte functions and provide evidence of immunomodulatory activities of S-adenosil-L-methionine and its capacity to antagonize chenodeoxycholic acid-mediated inhibition of lymphocyte proliferation and interleukin 2 secretion.