Tumour necrosis factor-alpha and soluble Fas ligand as biomarkers in non-acetaminophen-induced acute liver failure

Correlation between serum pro-inflammatory cytokine levels and the prognosis of the patients with acute liver failure

BACKGROUND AND AIM

The prognosis of acute liver failure (ALF) remains poor, and liver transplantation is an alternative treatment option. Assessing the prognosis of ALF is important in determining treatment strategies. Here, we investigated clinical factors including serum pro-inflammatory cytokine levels that are associated with the prognosis of ALF.

METHODS

Sixty-six patients who developed ALF were enrolled in this study. Serum concentrations of 12 pro-inflammatory cytokines were measured on admission. The prognosis and factors associated with survival and development of hepatic coma were analyzed.

RESULTS

Of 66 patients, 4 patients underwent liver transplantation, and 49 patients were rescued without liver transplantation, while the remaining 13 patients died. Serum concentrations of interleukin (IL)-1β, IL-4, IL-6, IL-8, IL-13, TNF, IFN -γ, IP-10, and G-CSF were significantly elevated in ALF patients. IL-4 and IL-8 levels were higher in patients who underwent liver transplantation or died than in rescued patients. Multivariable analysis identified age ≥ 55 years and IL-4 ≥ 1.2 pg/mL on admission as independent factors for mortality. Serum IL-8 levels were higher in patients with hepatic coma, and prothrombin-international normalized ratio ≥ 3.5 and IL-8 ≥ 77.2 pg/mL on admission were associated with development of hepatic coma after admission.

CONCLUSION

Serum levels of several pro-inflammatory cytokines were elevated in ALF patients. IL-4 and IL-8 were correlated with survival and development of hepatic coma after admission, respectively. Measurement of serum pro-inflammatory cytokines seems to be useful for the management of ALF.

Association of cytokines in hepatitis E with pregnancy outcome

AIMS

The aim of this study was to evaluate tumour necrosis factor-alpha (TNF-α), interleukin (IL)-6, interferon gamma (IFN-γ) and transforming growth factor-beta1 (TGF-β1) in hepatitis E infection during pregnancy and its relation with pregnancy outcome.

METHODS

A total of 272 pregnant and 219 non-pregnant women with hepatitis and 262 age and gestational age matched healthy pregnant women and 208 age matched, healthy non-pregnant women were evaluated on the basis of history, clinical examination, liver function profile. Serological tests of hepatitis A, B, C and E and cytokines using commercially available (ELISA) kits. The patients with hepatitis E were further evaluated for viral load by Real Time PCR. All these were followed till delivery for pregnancy outcome.

RESULTS

HEV viral load in acute viral hepatitis (AVH) and fulminant hepatic failure (FHF) of pregnant women were comparatively higher than non-pregnant women. Significantly higher levels of TNF-α, IL-6, IFN-γ and TGF-β1 were present in HEV infected pregnant women compared to non-pregnant women and controls. TNF-α, IL-6 and IFN-γ had significant positive correlation with viral load, serum bilirubin and prothrombin time in pregnant women. Higher levels of all four cytokines were found in pregnant women with HEV infection having adverse pregnancy outcome compared to that of pregnant women with non-HEV infection and controls.

CONCLUSION

In conclusion, severity of HEV infection and associated adverse pregnancy outcome might be mediated by cytokine in pregnancy.

Principles of liver regeneration and growth homeostasis

Liver regeneration is perhaps the most studied example of compensatory growth aimed to replace loss of tissue in an organ. Hepatocytes, the main functional cells of the liver, manage to proliferate to restore mass and to simultaneously deliver all functions hepatic functions necessary to maintain body homeostasis. They are the first cells to respond to regenerative stimuli triggered by mitogenic growth factor receptors MET (the hepatocyte growth factor receptor] and epidermal growth factor receptor and complemented by auxiliary mitogenic signals induced by other cytokines. Termination of liver regeneration is a complex process affected by integrin mediated signaling and it restores the organ to its original mass as determined by the needs of the body (hepatostat function). When hepatocytes cannot proliferate, progenitor cells derived from the biliary epithelium transdifferentiate to restore the hepatocyte compartment. In a reverse situation, hepatocytes can also transdifferentiate to restore the biliary compartment. Several hormones and xenobiotics alter the hepatostat directly and induce an increase in liver to body weight ratio (augmentative hepatomegaly). The complex challenges of the liver toward body homeostasis are thus always preserved by complex but unfailing responses involving orchestrated signaling and affecting growth and differentiation of all hepatic cell types.

Construction and identification of recombinant replication-defective adenovirus vector Αd/CMV/V5-DEST-TNFα-scFv

AIM: To construct a recombinant replication-defective adenovirus vector carrying TNFα-scFv and to obtain high-purity virus solution by viral packaging, purification and titration.

METHODS: The TNFα-scFv gene was amplified from the PUC57-Αmp vector and cloned into the shuttle plasmid pDONR221. The resulting pDONR221-TNFα-scFv was identified by DNA sequencing and then co-transfected into bacteria carrying the adenoviral backbone plasmid pΑd-CMV-V5-DEST to generate an adenoviral plasmid carrying TNFα-scFv (pΑd/CMV/V5-DEST-TNFα-ScFv) by homologous recombination in bacteria. After the pΑd/CMV/V5-DEST-TNFα-ScFv vector was transfected into 293 cells, the transfected 293 cells were infected with adenoviruses. The expression of TNFα-ScFv was detected by cytopathic effect and Western blot.

RESULTS: PCR amplification, restriction analysis and DNA sequencing verified that both the recombinant shuttle plasmid pDONR221-TNFα -scFv and the recombinant adenovirus vector pΑd/CMV/V5-DEST-TNFα-scFv were correctly constructed. After amplification and purification, the titer of recombinant adenovirus was 2.5×10¹¹ TCID 50/mL after proliferation in 293 cells. Western blot analysis demonstrated that TNFα-scFv was expressed efficiently in 293 cells after infection.

CONCLUSION: The recombinant adenovirus vector Αd/CMV/V5-DEST-TNFα-scFv has been successfully constructed, which lays a foundation for further study of gene function and therapy.

Serum tumor necrosis factor-alpha level in hepatitis E virus-related acute viral hepatitis and fulminant hepatic failure in pregnant women

AIM

The host response in hepatitis E virus (HEV)-related liver disease of pregnant women is unclear. This study was carried out to evaluate the serum concentration of tumor necrosis factor (TNF)-α in HEV-related acute viral hepatitis (AVH) and fulminant hepatic failure (FHF) in pregnant women in relation to pregnancy outcome.

METHODS

The study included 262 pregnant and 158 non-pregnant women with jaundice. There were 160 healthy asymptomatic pregnant women and 124 healthy asymptomatic non-pregnant women as controls. The jaundiced patients were classified as AVH or FHF. Serum TNF-α level was assayed by commercially available enzyme-linked immunoassay kits.

RESULTS

A significantly higher level of TNF-α was observed in HEV-infected pregnant women than non-HEV pregnant women (P < 0.001). TNF-α level was significantly higher in AVH and FHF of HEV-infected pregnant women compared with AVH and FHF of HEV infected non-pregnant women (P = 0.036 and P = 0.010, respectively). The HEV-infected pregnant FHF expired group had significantly higher levels of TNF-α than the non-pregnant FHF expired group (P = 0.025). TNF-α levels were significantly higher in AVH of HEV-infected pregnant women than healthy pregnant controls (P < 0.001). Higher TNF-α levels were observed in HEV-infected women having preterm delivery and low birthweight newborns compared with non-HEV and healthy pregnant women.

CONCLUSION

Higher serum concentration of TNF-α observed in HEV infected AVH and FHF pregnant cases shows that pregnancy with HEV infection increases TNF-α secretion. TNF-α may be an important factor in the outcomes of pregnancy due to HEV infection.

Knowledge-based identification of soluble biomarkers: hepatic fibrosis in NAFLD as an example

The discovery of biomarkers is often performed using high-throughput proteomics-based platforms and is limited to the molecules recognized by a given set of purified and validated antigens or antibodies. Knowledge-based, or systems biology, approaches that involve the analysis of integrated data, predominantly molecular pathways and networks may infer quantitative changes in the levels of biomolecules not included by the given assay from the levels of the analytes profiled. In this study we attempted to use a knowledge-based approach to predict biomarkers reflecting the changes in underlying protein phosphorylation events using Nonalcoholic Fatty Liver Disease (NAFLD) as a model. Two soluble biomarkers, CCL-2 and FasL, were inferred in silico as relevant to NAFLD pathogenesis. Predictive performance of these biomarkers was studied using serum samples collected from patients with histologically proven NAFLD. Serum levels of both molecules, in combination with clinical and demographic data, were predictive of hepatic fibrosis in a cohort of NAFLD patients. Our study suggests that (1) NASH-specific disruption of the kinase-driven signaling cascades in visceral adipose tissue lead to detectable changes in the levels of soluble molecules released into the bloodstream, and (2) biomarkers discovered in silico could contribute to predictive models for non-malignant chronic diseases.

Increase in soluble CD95L during subacute phases after human spinal cord injury: a potential therapeutic target

STUDY DESIGN

A pilot study measuring the levels of serum-soluble CD95 ligand (CD95L) in eight spinal cord-injured patients.

OBJECTIVES

To determine the soluble concentration of CD95L in spinal cord injury (SCI) patients after trauma.

METHODS

We collected blood samples from eight patients with acute traumatic SCI. Soluble CD95L serum levels were determined using an enzyme-linked immunosorbent assay. American Spinal Injury Association (ASIA) was determined according to ASIA classification. The patients were monitored, and venous blood was drawn after arrival at the hospital on the 1st and 3rd day and during the 1st, 2nd, 4th, 8th and 12th weeks after trauma.

RESULTS

The average patient age was 48.1 years (18-86 years). Three patients were paraplegic (two incomplete, one complete), five were quadriplegic (one complete, four incomplete). The serum concentration of soluble CD95L (sCD95L) decreased during the 1st week (41 ng(- l)) and increased after the 2nd week in all eight patients. It peaked during the 4th week (68.5 ng (- l)) and reached a plateau during the 12th week (76.2 ng (- l)). There are many possible explanations for not being able to detect a statistical significance, one of course being the small sample size.

CONCLUSION

Promising results for anti-CD95L therapy have already been documented in lab studies with rodents. Anti-CD95L blocks the pro-apoptotic and proinflammatory activity of membrane-bound CD95L during the acute phase of SCI. We observed that sCD95L levels are elevated during the subacute and intermediate phases of SCI. It would be of great interest to study a larger group of patients to determine whether higher sCD95 levels are correlated with improved or impaired neurological outcome or with increasing levels of autoimmune components in peripheral blood.

Cell-free DNA as a potential marker to predict carbon tetrachloride-induced acute liver injury in rats

PURPOSE

Finding an optimal biomarker for the noninvasive evaluation of acute liver injury (ALI) may be of great value in predicting clinical outcomes and investigating potential treatments. We investigated cell-free DNA (CFD) as a potential biomarker to predict carbon tetrachloride-induced ALI in rats.

METHODS

Forty-five Sprague-Dawley rats were randomly assigned to three groups. ALI was induced by carbon tetrachloride via a nasogastric tube at 1, 2.5, or 5 ml/kg of a 50 % solution. Fifteen additional rats underwent a sham procedure. Blood samples were drawn at time t which was 0 (baseline), 3, 6, 12, 24, 48, 72, 96, and 120 h for the measurements of CFD, glutamate-pyruvate transaminase (GPT), glutamate-oxaloacetate transaminase (GOT), and total bilirubin. Prothrombin time and histology were examined at 24 and 120 h following injection of 5 ml/kg carbon tetrachloride in 18 additional rats and in 10 control rats.

RESULTS

CFD levels in rats subjected to carbon tetrachloride-induced ALI were significantly increased in all blood samples starting at 12 h after the induction of ALI (p < 0.001), reaching peak levels at 24 h. Blood GOT, GPT, and total bilirubin were elevated in all blood samples starting at 3 h after the induction of ALI (p < 0.0001), reaching peak levels by 48 h. A positive correlation was demonstrated between CFD levels and GOT (R (2) = 0.92), GPT (R (2) = 0.92), and total bilirubin (R (2) = 0.76). CFD levels correlated with liver damage seen on histological examination, as well as predicted liver damage, at 24 h after ALI.

CONCLUSIONS

CFD may be a useful biomarker for the prediction and measurement of ALI. There is no evidence to suggest that CFD is superior to other available noninvasive biomarkers.

Systematic review: acute liver failure - one disease, more than 40 definitions

BACKGROUND

Acute liver failure (ALF) is a clinical syndrome with very high mortality estimates ranging between 60% and 80%.

AIM

To investigate the explicitness and extent of variability in the used ALF definitions in the ALF prognostic literature.

METHODS

All studies that pertain to the prognosis of patients with ALF were electronically searched in MEDLINE (1950-2012) and EMBASE (1950-2012). Identified titles and abstracts were independently screened by three reviewers to determine eligibility for additional review. We included English articles that reported original data from clinical trials or observational studies on ALF patients.

RESULTS

A total of 103 studies were included. Of these studies 87 used 41 different ALF definitions and the remaining 16 studies did not report any explicit ALF definition. Four components underlying ALF definitions accounted for the differences: presence and/or grading of hepatic encephalopathy (HE); the interval between onset of disease and occurrence of HE; presence of coagulopathy and pre-existing liver disease.

CONCLUSIONS

The diversity in acute liver failure definitions hinders comparability and quantitative analysis among studies. There is room for improvement in the reporting of acute liver failure definitions in prognostic studies. The result of this review may be useful as a starting point to create a uniform acute liver failure definition.

Biomarkers for drug-induced liver injury

Of the estimated 10,000 documented human drugs, more than 1000 have been associated with drug-induced liver injury (DILI), although causality has not always been established clearly. Numerous biomarkers for DILI have been explored, but less than ten are adopted or qualified as valid by the US FDA. The biomarkers for DILI are individual or a panel of proteins, nucleic acids or metabolites from various sources, such as the liver, blood and urine. While most DILI biomarkers are drug independent, some possibly 'drug-specific' DILIs have been explored, but specificity and sensitivity of both types need to be improved for the diagnosis of DILI during drug development and in clinical practice. Novel approaches for DILI biomarkers have been actively investigated recently, but produced mainly animal-based biomarkers, which are possibly useful for drug development, but are not suitable or have not been validated for clinical applications. This review summarizes the current practice and future perspectives for DILI biomarkers.

Liver regeneration after partial hepatectomy: critical analysis of mechanistic dilemmas

Liver regeneration after partial hepatectomy is one of the most studied models of cell, organ, and tissue regeneration. The complexity of the signaling pathways initiating and terminating this process have provided paradigms for regenerative medicine. Many aspects of the signaling mechanisms involved in hepatic regeneration are under active investigation. The purpose of this review is to focus on the areas still not well understood. The review also aims to provide insights into the ways by which current concepts of liver regeneration can provide understanding regarding malfunction of the regenerative process in liver diseases, such as acute liver failure.