Interferon-alpha 2b therapy reduces liver fibrosis in chronic non-A, non-B hepatitis: a quantitative histological evaluation

SOFTWARE-ASSISTED IMAGE ANALYSIS FOR IDENTIFICATION AND QUANTIFICATION OF HEPATIC SINUSOIDAL DILATATION AND CENTRILOBULAR FIBROSIS

Background:

Heart dysfunction and liver disease often coexist because of systemic disorders. Any cause of right ventricular failure may precipitate hepatic congestion and fibrosis. Digital image technologies have been introduced to pathology diagnosis, allowing an objective quantitative assessment. The quantification of fibrous tissue in liver biopsy sections is extremely important in the classification, diagnosis and grading of chronic liver disease.

Aim:

To create a semi-automatic computerized protocol to quantify any amount of centrilobular fibrosis and sinusoidal dilatation in liver Masson’s Trichrome-stained specimen.

Method:

Once fibrosis had been established, liver samples were collected, histologically processed, stained with Masson’s trichrome, and whole-slide images were captured with an appropriated digital pathology slide scanner. After, a random selection of the regions of interest (ROI’s) was conducted. The data were subjected to software-assisted image analysis (ImageJ^®).

Results:

The analysis of 250 ROI’s allowed to empirically obtain the best application settings to identify the centrilobular fibrosis (CF) and sinusoidal lumen (SL). After the establishment of the colour threshold application settings, an in-house Macro was recorded to set the measurements (fraction area and total area) and calculate the CF and SL ratios by an automatic batch processing.

Conclusion:

Was possible to create a more detailed method that identifies and quantifies the area occupied by fibrous tissue and sinusoidal lumen in Masson’s trichrome-stained livers specimens.

Appraising diagnostic performance of ELF test by pathological staging and digital quantification of liver fibrosis

INTRODUCTION AND OBJECTIVES

A crucial issue when appraising the performance of non-invasive markers is the limitations of the reference standard they are compared to. Digital image analysis (DIA) was suggested as a reproducible approach expressing fibrosis numerically as a proportionate area (PA) (%). We aimed to evaluate ELF test with direct reference to PA (%), thereby explore the improvement in accuracy to discriminate significant fibrosis which may actually have been underestimated by categorical pathological staging.

MATERIALS AND METHODS

PA (%) data were obtained by DIA of trichrome-stained liver biopsies of 52 chronic hepatitis patients. Paired serum samples of patients and additional 36 controls were performed to measure ELF test. Diagnostic performance characteristics of ELF test was derived in predicting significant fibrosis in the patient cohort, and also, in distinguishing healthy controls from patients with significant fibrosis.

RESULTS

We found an AUROC value of 0.73 for ELF to predict significant fibrosis as assessed by DIA and a lower AUROC value of 0.66 when assessed by conventional pathology. Importantly, ELF test provided considerably high diagnostic accuracy to discriminate healthy controls from patients with significant fibrosis defined by Ishak F≥2 and TPA≥5% (AUROCs 0.93 and 0.94, respectively) with optimal ELF cut-off point of 8.4 for both.

CONCLUSIONS

Digital quantification could represent a better reference standard than conventional pathology allowing a better discriminatory capability for ELF test. ELF test provided high diagnostic accuracy to discriminate healthy controls from patients with significant fibrosis suggesting a role as a screening strategy in the community setting.

Usefulness of morphometric image analysis with Sirius Red to assess interstitial fibrosis after renal transplantation from uncontrolled circulatory death donors

Early interstitial fibrosis (IF) correlates with long-term renal graft dysfunction, highlighting the need for accurate quantification of IF. However, the currently used Banff classification exhibits some limitations. The aim of our study was to precisely describe the progression of IF after renal transplantation using a new morphometric image analysis method relying of Sirius Red staining. The morphometric analysis we developed showed high inter-observer and intra-observer reproducibility, with ICC [95% IC] of respectively 0.75 [0.67–0.81] (n = 151) and 0.88 [0.72–0.95] (n = 21). We used this method to assess IF (mIF) during the first year after the kidney transplantation from 66 uncontrolled donors after circulatory death (uDCD). Both mIF and interstitial fibrosis (ci) according to the Banff classification significantly increased the first three months after transplantation. From M3 to M12, mIF significantly increased whereas Banff classification failed to highlight increase of ci. Moreover, mIF at M12 (p = 0.005) correlated with mean time to graft function recovery and was significantly associated with increase of creatininemia at M12 and at last follow-up. To conclude, the new morphometric image analysis method we developed, using a routine and cheap staining, may provide valuable tool to assess IF and thus to evaluate new sources of grafts.

Quantification of Liver Fibrosis—A Comparative Study

Liver disease has been targeted as the fifth most common cause of death worldwide and tends to steadily rise. In the last three decades, several publications focused on the quantification of liver fibrosis by means of the estimation of the collagen proportional area (CPA) in liver biopsies obtained from digital image analysis (DIA). In this paper, early and recent studies on this topic have been reviewed according to these research aims: the datasets used for the analysis, the employed image processing techniques, the obtained results, and the derived conclusions. The purpose is to identify the major strengths and “gray-areas” in the landscape of this topic.

Characterization of fibrosis changes in chronic hepatitis C patients after virological cure: A systematic review with meta-analysis

BACKGROUND AND AIM

Virological cure becomes available for most patients with chronic hepatitis C (CHC), but residual fibrosis can be an independent risk factor for liver-related complications. We aimed to characterize fibrosis change in CHC patients achieved virological cure.

METHODS

We did a systematic literature search for studies that had pre and post-treatment evaluations of histologic fibrosis in CHC patients with sustained virological response (SVR). We identified the association of SVR with the incidence, extent, and velocity of fibrosis change.

RESULTS

Overall, 3243 patients were included. Interferon-based regimens were used for all the patients, achieving a median SVR prevalence of 36.2%. Biopsy interval ranged from 1 to 10 years. Mean baseline fibrosis score (METAVIR) was 2.3 points. Compared with non-SVR patients, SVR patients could have higher incidence of fibrosis regression (35.1% vs 17.0%; OR: 3.3; P < 0.001), regardless of baseline fibrosis severity, way of biopsy evaluation, treatment regimen, or study design, and could have more extent of reduction (-0.31 points vs -0.00 points; P = 0.004). Baseline advanced fibrosis (F > 2) was associated with more rapid regression in both SVR and non-SVR patients (P < 0.05 for both). SVR patients could have lower incidence of fibrosis progression and maintenance than non-SVR patients by 4.8% versus 23.1% (OR: 0.20; P = 0.008) and 42.9% versus 55.2% (OR: 0.53; P < 0.001), respectively.

CONCLUSIONS

There could be a favorable characteristic of fibrosis regression in SVR patients. However, residential fibrosis may remain an issue because of a non-ignorable prevalence of fibrosis maintenance among these patients.

Magnetic resonance elastography of liver

Magnetic resonance elastography (MRE) assesses tissue stiffness in vivo by imaging propagating shear waves through the tissues and processing the wave information. MRE is a robust technology with excellent technical success; is applicable in almost all patients and body habitus; and has excellent reproducibility, repeatability, and interobserver agreement for assessing liver stiffness. It is currently the most accurate noninvasive technique for detection and staging of liver fibrosis and has the potential to replace liver biopsy. This article describes the principles and technique of MRE, current clinical applications, and emerging clinical indications.

An inexpensive and worldwide available digital image analysis technique for histological fibrosis quantification in chronic hepatitis C

Hepatic fibrosis staging is based on semiquantitative scores. Digital imaging analysis (DIA) appears more accurate because fibrosis is quantified in a continuous scale. However, high cost, lack of standardization and worldwide unavailability restrict its use in clinical practice. We developed an inexpensive and widely available DIA technique for fibrosis quantification in hepatitis C, and here, we evaluate its reproducibility and correlation with semiquantitative scores, and determine the fibrosis percentage associated with septal fibrosis and cirrhosis. 282 needle biopsies staged by Ishak and METAVIR scores were included. Images of trichrome-stained sections were captured and processed using Adobe(®) Photoshop(®) CS3 and Adobe(®) Bridge(®) softwares. The percentage of fibrosis (fibrosis index) was determined by the ratio between the fibrosis area and the total sample area, expressed in pixels calculated in an automated way. An excellent correlation between DIA fibrosis index and Ishak and METAVIR scores was observed (Spearman's r = 0.95 and 0.92; P < 0.001, respectively). Excellent intra-observer reproducibility was observed in a randomly chosen subset of 39 biopsies with an intraclass correlation index of 0.99 (95% CI, 0.95-0.99). The best cut-offs associated with septal fibrosis and cirrhosis were 6% (AUROC 0.97, 95% CI, 0.95-0.99) and 27% (AUROC 1.0, 95% CI, 0.99-1), respectively. This new DIA technique had high correlation with semiquantitative scores in hepatitis C. This method is reproducible, inexpensive and available worldwide allowing its use in clinical practice. The incorporation of DIA technique provides a more complete evaluation of fibrosis adding the quantification to architectural patterns.

Correlation of MR elastography with morphometric quantification of liver fibrosis (Fibro-C-Index) in chronic hepatitis B

PURPOSE

We evaluated the correlation of MR Elastography (MRE) with morphometric assessment of liver fibrosis in chronic hepatitis B (CHB).

METHODS

Thirty-two patients with CHB underwent both MRE and a liver biopsy within a 6-month interval. MRE was performed using standard MRE sequence on a 1.5 Tesla clinical scanner. The liver stiffness (LS) was measured on automatically generated stiffness maps. Morphometric quantification of fibrosis of liver biopsies was performed using a semi-automated image analysis program and expressed as percentage area (Fibro-C-Index). Correlations between MRE, Fibro-C-Index, and histologic fibrosis stages were evaluated. Receiver operating curve (ROC) analysis of MRE and Fibro-C-index for differentiating fibrosis (≥F1), significant fibrosis (≥F2), advanced fibrosis (≥F3), and cirrhosis (F4) was performed.

RESULTS

MRE showed excellent correlation with both Fibro-C-Index (r = 0.78, 95% confidence interval [CI], 0.59-0.88, P < 0.001) and histologic staging (rho = 0.87, 95% CI, 0.72-0.94, P < 0.0001). Significant differences in MRE (P = 0.0001) and Fibro-C-Index (P = 0.003) among different stages of liver fibrosis was found. MRE and Fibro-C-Index had similar accuracies for differentiating fibrosis stages: ≥F1 (0.87 versus 0.81, P = 0.6), ≥F2 (0.95 versus 0.94, P = 0.78), ≥F3 (0.98 versus 0.96, P = 0.76), and F4 (1.00 versus 0.92, P = 0.10).

CONCLUSION

MRE is an excellent noninvasive indicator of liver fibrosis burden in CHB.

Comparative assessment of liver fibrosis by computerized morphometry in naïve patients with chronic hepatitis B and C

BACKGROUND

Liver fibrosis, now assessed by liver biopsy or using non-invasive methods, might be different in chronic hepatitis B (CHB) and chronic hepatitis C (CHC).

AIM

To compare histological amount and pattern of fibrosis in CHB and CHC.

METHODS

Sixty CHB and sixty CHC biopsies from naïve patients, standardized for the spectrum of Metavir fibrosis stages, were analysed for (1) semi-quantitative Metavir activity, steatosis, perisinusoidal fibrosis, alpha-smooth muscle actin immunoreactivity, (2) quantitative morphometry of total and perisinusoidal fibrosis ratio (FR and PFR).

RESULTS

Biopsy quality, activity, steatosis, Fibrotest(®) values were not different between the two groups. Correlation between FR and fibrosis stage was stronger in CHB (r = 0.90) than CHC (r = 0.81). Mean FR was 1.5-fold higher in CHC than CHB for early fibrosis stages (F ≤ 2, P = 0.001), with higher PFR in CHC for F0 (P = 0.001), F1 (P = 0.08) and F2 (P = 0.004). Hepatic stellate cell activation index was also higher in CHC than in CHB (P = 0.007). Diagnosis performance of FR for significant fibrosis was not statistically different in CHB than CHC (AUROC 0.92 and 0.87 respectively), but cut-offs optimizing sensitivity and specificity were higher in CHC and their extrapolation to CHB led to 10% decrease in sensitivity. In F ≤ 2 patients, correlation between FR and Fibrotest(®) was only significant in CHC.

CONCLUSIONS

As compared to CHB, amount of fibrosis is greater in CHC for F ≤ 2 patients, mainly because of higher perisinusoidal fibrosis. These data illustrate difficulty to assess early fibrosis stages by non-invasive methods, and support the need for specific cut-offs in CHB.

Study of the effect of antiviral therapy on homocysteinemia in hepatitis C virus- infected patients

BACKGROUND

Hepatitis C virus (HCV) infection is one of the leading causes of chronic liver disease (CLD). About 80% of those exposed to the virus develop a chronic infection. Hyperhomocysteinemia, which is an independent risk factor for atherosclerotic vascular disease and thromboembolism, may develop in HCV-infected patients although altered alanine amino transferase (ALT) enzyme levels are generally associated with damage to liver cells. The gold standard therapy for chronic hepatitis C patients is pegylated interferon combined with an anti-viral drug (ribavirin). The current study aimed to investigate the effect of antiviral therapy on plasma homocysteine (Hcy) levels in HCV patients in addition to other parameters.

METHODS

532 HCV-infected patients and 70 healthy controls were recruited for the study. All patients were subjected to laboratory investigations including HCV-RNA levels, complete blood cell counts, serum levels of homocysteine, ALT, alkaline phosphatase (ALP), lipid profile and liver ultrasonographic examination. The outcome of treatment with pegylated interferon α plus ribavirin treatment and sustained virologic response (SVR) was determined 6-9 months post-therapy.

RESULTS

Hyperhomocysteinemia was found in 91.35% of HCV-infected patients. The difference in plasma Hcy concentrations reached statistical significance between the patient and control groups. ALT, cholesterol and triglycerides (TGs) levels were found higher than normal in the patients group. After receiving a combined therapy for 24 weeks, 43.66% patients showed an SVR (responders); 30.98% patients were non-responders while 25.35% patients initially responded to therapy but again retrieved positive status of HCV infection six months post-therapy (relapse-cirrhotic patients). The mean levels of plasma Hcy, ALT and ALP were significantly reduced in responders within 10 weeks of therapy when compared with non-responders and relapse-cirrhotic patients.

CONCLUSION

Elevated homocysteine levels in serum due to HCV infection can be reduced to normal range with the standard interferon α plus ribavirin treatment. This study highlights the significance of the measurement of serum homocysteine levels in the diagnosis and monitoring of HCV infection treatment in addition to other laboratory parameters.

Immunohistochemical quantification of fast-myosin in frozen histological sections of goat limb muscles

Fast-myosin in frozen histological sections of eight, 10, 11 and nine muscles of the upper forelimb, lower forelimb, upper hindlimb and lower hindlimb, respectively, of goats was quantified by an immunohistochemical micromethod based on the enzyme-linked immunosorbent assay. The structure of the muscles is well preserved during the immunohistochemical measurement. High fast-myosin levels (more than 201 mg/g total protein) were observed in the triceps brachii (lateral head), rectus femoris, vastus lateralis, semitendinosus, semimembranosus, gastrocnemius (lateral head) and long digital extensor muscles. In contrast, low fast-myosin levels (less than 50 mg/g) were found in the triceps brachii (medial head), superficial digital flexor, vastus intermedialis, and soleus muscles. Fast-myosin-positive fibres (type II or fast-twitch type) were distributed more in the superficial regions than in the deeper regions in the triceps brachii (lateral and long heads), biceps brachii, brachialis, biceps femoris, vastus lateralis, vastus medialis, semimembranosus and gastrocnemius (lateral and medial heads) muscles. In contrast, type IIfibres were distributed more in the deeper regions than in the superficial regions in the extensor carpi radialis, deep digital flexor, cranial tibial, deep digital flexor and superficial digital flexor muscles. When the results obtained by the immunohistochemical micromethod were compared with those obtained by biochemical techniques and by histomorphometrical analyses, high correlations were noted. This technique could be used in research projects to study the muscle characteristics that determine meat quality.

The relationship between liver disease stage and liver fibrosis: a tangled web

The structural consequences of chronic liver disease are described as a series of liver disease 'stages' with scarring and architectural change that eventually destroys and replaces the normal lobular structure of the liver. Fibrosis ('excess collagen') and stage have been confused in histological staging systems. Fibrosis is part of increasing liver disease stage, but fibrosis and stage are different. Staging liver disease is important in routine histopathological assessment. Measurement of liver fibrosis is another process. The collagenous proportion of a liver biopsy [collagen proportionate area (CPA)] correlates with hepatic venous pressure gradient (HVPG), which is of recognized prognostic value. CPA at 1 year post-transplantation in hepatitis C virus-infected patients predicts subsequent clinical decompensation. CPA in cirrhotic patients predicts decompensation more accurately than staging or HVPG. The 'cirrhosis' stage category has poor prognostic power, and CPA effectively substages cirrhosis. CPA improves the description of liver disease stage. Proper validation of antifibrotic treatments and 'non-invasive markers of liver fibrosis' requires measurement of liver fibrosis (and not liver biopsy stage scores). It is unacceptable for the words 'fibrosis' and 'score' to remain next to each other. There are benefits to properly understanding liver fibrosis and liver disease stage and properly assessing each of them.

Non-invasive assessment of liver fibrosis progression in hepatitis C patients retreated for 96 weeks with antiviral therapy: a randomized study

BACKGROUND

The efficacy of a maintenance therapy in non-responder patients with chronic hepatitis C has been essentially evaluated by histological semiquantitative scores.

AIM

The aim was to evaluate the efficiency of 2 years of treatment with peginterferon alpha-2a vs alpha-tocopherol in these patients by histology, morphometry and blood markers of fibrosis.

METHOD

Hundred and five HCV patients with a Metavir fibrosis score > or = 2 were randomized to receive peginterferon alpha-2a 180 microg/week (PEG) (n=55) or alpha-tocopherol (TOCO) 1000 mg/day (n=50) for 96 weeks. The primary endpoint was improvement or stabilization of the Metavir fibrosis score by biopsy performed at week 96. Secondary endpoints included a quantitative assessment of fibrosis by morphometry and changes in blood markers of fibrosis.

RESULTS

There was no difference at baseline between PEG and TOCO according to the metavir (83.3 vs 86.8%, P=0.751) stage. The median fibrosis rate, measured with morphometry was 2.72 and 2.86% at day 0, and 3.66 and 2.82% at week 96, in the PEG and TOCO groups (P=0.90) respectively. However, the percentage of patients with metavir activity grade improvement was significantly higher in the PEG group vs the TOCO group (52.8 vs 23.7%, P=0.016). Non-invasive markers analysis did not show any significant change in both groups.

CONCLUSION

Long-term therapy with peginterferon alpha-2a did not reduce liver fibrosis degree assessed by morphometry and blood tests as compared with alpha-tocopherol. Blood tests could be useful to assess liver fibrosis changes in clinical trials.

Management of nonresponsive hepatitis C

More than 50% of hepatitis C virus (HCV)-infected patients do not respond to the classical pegylated interferon (PEG-IFN)/ribavirin combination therapy. However, failing to respond to one course of treatment is not synonymous of therapy failure and retreatment is often beneficial. Alternative retreatment strategies include repeating the classical standard of care with an optimized drug regimen and adherence, including ribavirin serum concentration adjustment, correcting, if at all possible, comorbidities, and the addition of new specific anti-HCV molecules to the backbone of pegylated interferon/ribavirin. Options of retreatment should include consensus and natural interferons. For patients with advanced disease exposed to a high risk of lethal complications, customized maintenance therapy could be an effective option since it may slow down complications in some patients. Since low-dose interferon monotherapy is not sufficient, such a maintenance therapy remains to be verified via clinical trials. New possibilities of noninvasive assessment of fibrosis and the use of genetic tests to predict fibrosis progression and responsiveness to interferon are major emerging opportunities that run parallel to the revolution of the pharmacologic armentarium.

Farglitazar lacks antifibrotic activity in patients with chronic hepatitis C infection

BACKGROUND & AIMS

Farglitazar (GI262570), an insulin-sensitizing agent, selectively binds and activates peroxisome proliferator-activated receptor gamma (PPARgamma) and inhibits stellate cell activation. We evaluated its antifibrotic effect in patients with chronic hepatitis C that did not respond to standard-of-care therapy.

METHODS

Patients with fibrosis of Ishak stages 2-4 (n = 265), based on analysis of liver biopsy samples, were randomly assigned to groups given once-daily doses of 0.5 mg farglitazar, 1.0 mg farglitazar, or placebo for 52 weeks; repeat liver biopsy samples were then obtained. The primary end points were changes in levels of alpha-smooth muscle actin (SMA) expression and collagen, based on morphometry and ranked histologic assessments.

RESULTS

Two hundred nine patients had paired biopsy specimens adequate for analysis (81.5% with pretreatment Ishak scores of stage 2 or 3). There was no overall difference in SMA (P = .58) or collagen (P = .99) levels at week 52. SMA levels increased by a median of 49% in samples from patients given placebo, 58% in patients given 0.5 mg farglitizar and 52% in patients given 1.0 mg farglitizar, respectively. Collagen increased by 27% in placebo samples and 31% in samples from patients given either dose of farglitizar. There were no significant differences between treatment groups in the ranked assessment of paired biopsy specimens or in the proportion of patients with a change in fibrosis score > or = Ishak stage.

CONCLUSIONS

In patients with chronic hepatitis C and moderate fibrosis, 52 weeks of treatment with farglitazar does not affect stellate cell activation or fibrosis (measured by morphometry or comparison of paired biopsy specimens).

Nonlinear optical microscopy: use of second harmonic generation and two-photon microscopy for automated quantitative liver fibrosis studies

Liver fibrosis is associated with an abnormal increase in an extracellular matrix in chronic liver diseases. Quantitative characterization of fibrillar collagen in intact tissue is essential for both fibrosis studies and clinical applications. Commonly used methods, histological staining followed by either semiquantitative or computerized image analysis, have limited sensitivity, accuracy, and operator-dependent variations. The fibrillar collagen in sinusoids of normal livers could be observed through second-harmonic generation (SHG) microscopy. The two-photon excited fluorescence (TPEF) images, recorded simultaneously with SHG, clearly revealed the hepatocyte morphology. We have systematically optimized the parameters for the quantitative SHG/TPEF imaging of liver tissue and developed fully automated image analysis algorithms to extract the information of collagen changes and cell necrosis. Subtle changes in the distribution and amount of collagen and cell morphology are quantitatively characterized in SHG/TPEF images. By comparing to traditional staining, such as Masson's trichrome and Sirius red, SHG/TPEF is a sensitive quantitative tool for automated collagen characterization in liver tissue. Our system allows for enhanced detection and quantification of sinusoidal collagen fibers in fibrosis research and clinical diagnostics.

Liver fibrosis

Liver damage leads to an inflammatory response and to the activation and proliferation of mesenchymal cell populations within the liver which remodel the extracellular matrix as part of an orchestrated wound-healing response. Chronic damage results in a progressive accumulation of scarring proteins (fibrosis) that, with increasing severity, alters tissue structure and function, leading to cirrhosis and liver failure. Efforts to modulate the fibrogenesis process have focused on understanding the biology of the heterogeneous liver fibroblast populations. The fibroblasts are derived from sources within and out with the liver. Fibroblasts expressing alpha-smooth muscle actin (myofibroblasts) may be derived from the transdifferentiation of quiescent hepatic stellate cells. Other fibroblasts emerge from the portal tracts within the liver. At least a proportion of these cells in diseased liver originate from the bone marrow. In addition, fibrogenic fibroblasts may also be generated through liver epithelial (hepatocyte and biliary epithelial cell)-mesenchymal transition. Whatever their origin, it is clear that fibrogenic fibroblast activity is sensitive to (and may be active in) the cytokine and chemokine profiles of liver-resident leucocytes such as macrophages. They may also be a component driving the regeneration of tissue. Understanding the complex intercellular interactions regulating liver fibrogenesis is of increasing importance in view of predicted increases in chronic liver disease and the current paucity of effective therapies.

Bioconjugation of oligonucleotides for treating liver fibrosis

Liver fibrosis results from chronic liver injury due to hepatitis B and C, excessive alcohol ingestion, and metal ion overload. Fibrosis culminates in cirrhosis and results in liver failure. Therefore, a potent antifibrotic therapy is urgently needed to reverse scarring and eliminate progression to cirrhosis. Although activated hepatic stellate cells (HSCs) remain the principle cell type responsible for liver fibrosis, perivascular fibroblasts of portal and central veins as well as periductular fibroblasts are other sources of fibrogenic cells. This review will critically discuss various treatment strategies for liver fibrosis, including prevention of liver injury, reduction of inflammation, inhibition of HSC activation, degradation of scar matrix, and inhibition of aberrant collagen synthesis. Oligonucleotides (ODNs) are short, single-stranded nucleic acids, which disrupt expression of target protein by binding to complementary mRNA or forming triplex with genomic DNA. Triplex forming oligonucleotides (TFOs) provide an attractive strategy for treating liver fibrosis. A series of TFOs have been developed for inhibiting the transcription of alpha1(I) collagen gene, which opens a new area for antifibrotic drugs. There will be in-depth discussion on the use of TFOs and how different bioconjugation strategies can be utilized for their site-specific delivery to HSCs or hepatocytes for enhanced antifibrotic activities. Various insights developed in individual strategy and the need for multipronged approaches will also be discussed.

Relationship of serum fibrosis markers with liver fibrosis stage and collagen content in patients with advanced chronic hepatitis C

This study determined the utility of a panel of serum fibrosis markers along with routine laboratory tests in estimating the likelihood of histological cirrhosis in a cohort of prior nonresponders with chronic hepatitis C. The relationship between serum markers and quantitative hepatic collagen content was also determined. Liver biopsy samples from 513 subjects enrolled in the HALT-C trial were assigned Ishak fibrosis scores. The collagen content of 386 sirius-red stained, nonfragmented biopsy samples was quantified using computerized morphometry. Serum tissue inhibitor of matrix metalloproteinase-1 (TIMP-1), amino-terminal peptide of type III procollagen (PIIINP), hyaluronic acid (HA), and YKL-40 levels were determined using commercially available assays.Sixty-two percent of patients had noncirrhotic fibrosis (Ishak stage 2-4) whereas 38% had cirrhosis (Ishak stage 5,6). Multivariate analysis identified a 3-variable model (HA, TIMP-1, and platelet count) that had an area under the receiver operating curve (AUROC) of 0.81 for estimating the presence of cirrhosis. This model was significantly better than that derived from the cirrhosis discriminant score (AUROC 0.70), the AST-to-platelet ratio (AUROC 0.73), and a prior model developed in HALT-C patients (AUROC 0.79). Multivariate analysis demonstrated that the serum fibrosis markers correlated substantially better with Ishak fibrosis scores than with the log hepatic collagen content (AUROC 0.84 versus 0.72).

CONCLUSION

A 3-variable model consisting of serum HA, TIMP-1, and platelet count was better than other published models in identifying cirrhosis in HALT-C Trial subjects. The stronger correlation of the serum markers with Ishak scores suggests that serum fibrosis markers reflect the pattern of fibrosis more closely than the quantity of hepatic collagen.

Low-dose intermittent interferon-alpha therapy for HCV-related liver cirrhosis after curative treatment of hepatocellular carcinoma

AIM: To assess the efficacy of low-dose intermittent interferon (IFN) therapy in patients with hepatitis C virus (HCV)-related compensated cirrhosis who had received curative treatment for primary hepatocellular carcinoma (HCC).

METHODS: We performed a prospective case controlled study. Sixteen patients received 3 MIU of natural IFN-alpha intramuscularly 3 times weekly for at least 48 wk (IFN group). They were compared with 16 matched historical controls (non-IFN group).

RESULTS: The cumulative rate of first recurrence of HCC was not significantly different between the IFN group and the non-IFN group (0% vs 6.7% and 68.6% vs 80% at 1- and 3-year, P = 0.157, respectively). The cumulative rate of second recurrence was not also significantly different between the IFN group and the non-IFN group (0% vs 6.7% and 35.9% vs 67% at 1- and 3-year, P = 0.056, respectively). Although the difference in the Child-Pugh classification score between the groups at initial treatment of HCC was not significant, the score was significantly worse at the time of data analysis in the non-IFN group than IFN group (7.19 ± 1.42 vs 5.81 ± 0.75, P = 0.0008). The cumulative rate of deviation from objects of any treatment for recurrent HCC was also higher in the non-IFN group than IFN group (6.7% and 27% vs 0 and 0% at 1- and 3-year, P = 0.048, respectively).

CONCLUSION: Low-dose intermittent IFN-alpha therapy for patients with HCV-related compensated cirrhosis after curative HCC treatment was effective by making patients tolerant to medical or surgical treatment for recurrent HCC in the later period of observation.

Effect of prolonged interferon therapy on the outcome of hepatitis C virus-related cirrhosis: a randomized trial

BACKGROUND & AIMS

The impact of interferon (IFN) treatment on the occurrence of complications related to hepatitis C virus (HCV)-related cirrhosis is debated because the majority of studies are retrospective. We designed a randomized controlled trial comparing the efficacy of prolonged IFN alfa-2a treatment vs nontreatment on complication-free survival in patients with compensated HCV cirrhosis.

METHODS

A total of 102 patients (mean age, 60.5 +/- 9.5 y; male/female ratio, .82) with biopsy examination-proven HCV cirrhosis, Child-Pugh score A, who were hepatocellular carcinoma (HCC) free, and had at least 1 risk factor of complications were randomized to receive IFN or no therapy for 24 months.

RESULTS

During the follow-up evaluation, the complication rate was 24.5%: HCC occurred in 12 and decompensation unrelated to HCC occurred in 13 patients. The number of HCC patients was similar in both groups. The probability of complication-free survival was not significantly different between treated and untreated patients (98% and 72.3% vs 90% and 70.7% at 12 and 24 mo, respectively, P = .59). The median time until complication occurrence was 17.1 months in the treated group vs 13.6 months in the untreated group (P = .2).

CONCLUSIONS

This randomized controlled trial showed that a 2-year course of IFN has little or no impact on complication-free survival in patients with high-risk compensated HCV cirrhosis.

Progression of fibrosis in advanced chronic hepatitis C: evaluation by morphometric image analysis

Fibrosis progression in chronic liver disease has usually been evaluated by liver biopsy using insensitive semiquantitative numerical scores. An alternative to this is to measure fibrous tissue quantitatively using morphometric image analysis. The aim of this study was to quantify fibrosis progression in a cohort of patients with treatment-refractory chronic hepatitis C enrolled in a placebo-controlled clinical trial of interferon gamma-1b (IFN-gamma 1b) for the treatment of advanced hepatic fibrosis. We used morphometry to quantify the amount of fibrous tissue in liver biopsies performed at baseline and after 48 weeks in 245 patients who had paired unfragmented, adequate-sized specimens and correlated the results with clinical and laboratory parameters. Eighty-seven patients were treated with placebo and 158 with IFN-gamma 1b. No effect of the drug on fibrosis was found in the trial, and so data from all 245 patients were combined for analysis. At baseline, 78% had cirrhosis; 22%, bridging fibrosis. The mean morphometrically determined collagen content increased by 58% between baseline and 48 weeks. There were statistically significant but weak correlations of fibrosis with platelet count, albumin, bilirubin, INR, and hyaluronic acid; however, changes in these did not correlate with or predict changes in fibrosis in the liver biopsy.

CONCLUSION

In advanced chronic hepatitis C, fibrosis increases at a rapid pace that can only be detected by morphometry. This technique can be used in future therapeutic trials of agents to inhibit fibrosis progression.

Hépatite C et transplantation hépatique

Hepatitis C virus-related end-stage liver disease, alone or in combination with alcohol, has become the leading indication for liver transplantation in most transplant programs accounting for approximately half of transplants performed in European centers. Hepatitis C virus infection recurs virtually in every post-transplant patient. The natural history of hepatitis C after liver transplantation is variable. Progression of chronic hepatitis C virus is more aggressive after liver transplantation with a cumulative probability of developing graft cirrhosis estimated to reach 30% at 5 years. Approximately 10% of the patients with recurrent disease will die or require re-transplantation within 5 years post-transplantation. Several factors, including those related to the virus, the host, the environment and the donor, are probably implicated in the outcome. The immune status represents the main significant variable in influencing disease severity in hepatitis C virus-infected patients; with higher HCV viral load and the significant association described between the degree of immunosuppression and disease severity. Interventions to prevent, improve, or halt the recurrence of hepatitis C virus infection have been evaluated by multiple small studies worldwide with similar overall rates of virological clearance of approximately 9-30%. Current consensus recommends combination therapy with pegylated interferon and ribavirin for those patients with histological recurrence of hepatitis C virus infection and fibrosis. Therapy is adjusted to tolerance and rescued with granulocyte colony-stimulating factor and erythropoietin for bone marrow suppression. In this article we present a comprehensive review of post-transplant hepatitis C virus infection; in particular fibrosis progression and the major challenges according to treatment.

Prolonged Negative HCV-RNA Status Led to a Good Outcome in Chronic Hepatitis C Patients with Genotype 1b and Super-High Viral Load

OBJECTIVE

We examined whether a sustained negative HCV-RNA status for 48 weeks affects the outcome in patients with genotype 1b and super-high viral load, and also investigated whether the outcome is affected by the induction therapy of twice-daily pre-administrated interferon (IFN)-beta.

METHODS

78 eligible patients were divided into four groups. 40 were patients assigned to the short treatment protocol. 13 patients received 3 MU IFN-beta twice daily for 2 weeks followed by IFN-alpha2b+ribavirin for 22 weeks (beta-induction group: group 1). 27 patients received IFN-alpha2b+ribavirin for 24 weeks (standard combination group: group 2). 38 patients were assigned to the maintenance treatment protocol. All of the 13 in the beta-induction group (group 3) and 21 of 25 patients in the standard combination group (group 4) who were negative HCV-RNA PCR at week 24 had IFN monotherapy to maintain a negative HCV-RNA result for 48 weeks.

RESULTS

An HCV-RNA-negative status at week 24 was observed in 96% (25/26) of groups 1 and 3 versus in 79% (41/52) of groups 2 and 4 (p<0.01). The sustained virological response (SVR) was 38% (5/13) in group 1 and 11% (3/27) in group 2 (p<0.05). In the maintenance treatment, SVR was observed in 46% (6/13) of group 3 and 32% (8/25) of group 4 (NS).

CONCLUSIONS

A sustained negative HCV-RNA status for 48 weeks might be associated with viral elimination in patients with genotype 1 and super-high viral load.

A decade of trials of interferon-alpha for chronic hepatitis C. A meta-regression analysis

The most relevant randomized controlled trials of interferon-alpha (IFN) for naive patients with chronic hepatitis C (CHC) published in a decade, just before appearance of pegylated IFN trials in 2000, were included in this paper. Its purpose is to review the relationship between sustained biochemical response in active versus control group versus usual clinical variables as IFN regimens, cirrhosis, genotype and versus less frequently addressed variables as funding, methodological quality or location of principal author. Meta-analysis estimates of global treatment effect varied according to trial design: group 1=IFN versus placebo/no treatment, 32 RCTs, 2499 pts, OR 9.5 (6.3-14.2); group 2a=comparison of IFN schedules, 43 RCTs, 7454 pts, OR 1.6 (1.4-1.9); group 2b=IFN+other drugs versus standard IFN, 30 RCTs, 4737 pts, OR 2.0 (1.6-2.6). Fixed effects (arm-level) meta-regression on the complete data set (171 arms, 10,580 pts) revealed that sustained response was most likely in experimental arms of IFN+ribavirin or other drugs (OR 2.4), arms using yearly schedule (OR 2.0), trial principal author from Asia (OR 1.7), trial sample size >200 (OR 1.4) and arms enrolling less than 50% of cirrhotics (OR 1.3). Moreover, focus was on some significant interactions too, as the effect of trial's quality interacting to the recorded funding (more benefit if no-profit, less if for-profit) and the effect of trial funding interacting to the location of first author (more benefit if from Asia). Three main effects (experimental arm, cirrhosis, funding) and one interaction (funding*location of principal author) explained 31% of between study variability in a random-effect meta-regression. In a subgroup analysis on a data set including available information on HCV genotype (93 arms, around 7000 pts), meta-regression revealed that genotype 1 or 4 less than 50% per arm and specialistic journal were significant predictors of either biochemical (transaminases) or virological (HCV-RNA) sustained response, in a model including the same main effects identified in the complete data set analysis. Finally, although mostly captured by different IFN regimens along time, heterogeneity of effect in a large set of (not-pegylated) IFN trials was also explained by HCV genotype and variables of quality and reporting, such as trial's principal author from Asia.

Hepatic fibrosis: molecular mechanisms and drug targets

Liver fibrosis is the common response to chronic liver injury, ultimately leading to cirrhosis and its complications, portal hypertension, liver failure, and hepatocellular carcinoma. Efficient and well-tolerated antifibrotic drugs are currently lacking, and current treatment of hepatic fibrosis is limited to withdrawal of the noxious agent. Efforts over the past decade have mainly focused on fibrogenic cells generating the scarring response, although promising data on inhibition of parenchymal injury and/or reduction of liver inflammation have also been obtained. A large number of approaches have been validated in culture studies and in animal models, and several clinical trials are underway or anticipated for a growing number of molecules. This review highlights recent advances in the molecular mechanisms of liver fibrosis and discusses mechanistically based strategies that have recently emerged.

Histological response in patients treated by interferon plus ribavirin for hepatitis C virus-related severe fibrosis

BACKGROUND

Studies of viral hepatitis C have suggested that fibrosis can regress, at least in patients with sustained virological response. A recent study suggested that cirrhosis was reversible in sustained and non-virological responders.

AIM

To study fibrosis progression rate and cirrhosis reversion in patients treated for severe fibrosis with interferon or interferon + ribavirin.

PATIENTS AND METHODS

Ninety-nine patients were treated with interferon + ribavirin and 64 with interferon. The Metavir fibrosis score and the semiquantitative fibrosis score (SFS) were used to assess fibrosis.

RESULTS

In sustained responders, fibrosis progression rate decreased from 0.26 Metavir unit (interquartile range: 0.19-0.34) to -0.67 (-0.67 to 0) (P < 0.0001) and from 0.81 SFS unit (0.48-1.13) to -1.33 (-3.67 to 0) (P < 0.0001). In non-responders, fibrosis progression rate decreased from 0.25 Metavir unit (0.17-0.33) before treatment to 0 (0-0) during treatment (P = 0.002) and from 0.63 SFS unit (0.49-1.12) to 0 (-2.67-1.33) (P = 0.18). Six out of 18 (33%) sustained virological responders and four of 43 (9%) non-responders regressed from cirrhosis (F4) to severe fibrosis (F3) (P = 0.058). No patient with cirrhosis had a decrease of Metavir fibrosis score of 2 points.

CONCLUSION

Interferon can slow fibrosis progression in sustained virological responders with severe fibrosis. In patients with a non-virological response and treated for 12 months the fibrosis progression rate was nil, meaning that only fibrosis stabilization could be obtained in these patients. Then, longer treatment duration (3-4 years) could be evaluated in non-virological responders.

Effects of interferon treatment response on liver complications of chronic hepatitis C: 9-year follow-up study

OBJECTIVES

Fibrotic severity, biochemical indices of poor liver function, and sporadic transmission are independent predictors of liver complications among people with chronic hepatitis C. After accounting for these factors, we tested whether interferon treatment or the treatment response reduces the rate of liver cancer, liver-related death or transplantation, and other liver complications during extended follow-up.

METHODS

Liver clinic cohort of 455 patients with histologically proven chronic hepatitis C was followed prospectively for median 9 yr (IQ 6, 11 yr); 384 received interferon, 343 completed a treatment course. Liver complications were assessed in relation to treatment and treatment response in univariate and multivariate models, and survival to onset of liver-related complications was determined.

RESULTS

The annual incidence of total liver complications was 1.5% in treated and 2.9% in untreated patients and appeared quasilinear throughout 9-yr follow-up. Interferon treatment did not influence the rate of liver complications. However, the rate of complications increased exponentially with transition of the treatment response from sustained viral response (SVR), through response-relapse to nonresponse (or no treatment). By univariate analysis, response to interferon treatment was a significant predictor of complications. After adjustment for fibrosis score, serum albumin concentration and mode of transmission in a multivariate model, treatment response just failed to reach significance (p= 0.058) as a predictor of outcome.

CONCLUSIONS

Response to antiviral therapy, and particularly SVR, appears to reduce liver complications in chronic hepatitis C. However, in the absence of an antiviral treatment response, a course of interferon does not reduce risks of liver cancer or liver failure.

Fibrillin-1 expression in normal and fibrotic rat liver and in cultured hepatic fibroblastic cells: modulation by mechanical stress and role in cell adhesion

Fibrillin-1, together with elastin, is the main component of elastic fibers found throughout the extracellular space and responsible for the biomechanical properties of most tissues and organs. In this work, fibrillin-1 expression and modulation were explored in experimental rat liver fibrosis and in vitro; furthermore, the role of fibrillin-1 fragments on cell adhesion was analyzed. Fibrosis was induced by subjecting rats to common bile duct ligation for 72 h and 7 days or carbon tetrachloride (CCl(4)) treatment for 2 and 6 weeks. Immunohistochemistry showed that, after bile duct ligation, fibrillin-1, elastin, and alpha-smooth muscle actin colocalized in the developing portal connective tissue. In CCl(4)-treated animals, a similar colocalization was observed in septa; however, elastin deposition was not observed around activated alpha-smooth muscle actin-positive stellate cells of the parenchyma. Treatment with the profibrogenic mediator transforming growth factor-beta1 (TGF-beta1) greatly increased the fibrillin-1 expression of cultured liver fibroblasts. The level of fibrillin-1 expression was significantly higher in cells grown in restrained (stressed) collagen lattices compared with those grown in unrestrained collagen lattices. Cell adhesion on the C-terminal fragment of fibrillin-1 containing the RGD sequence (rF6H) slightly increased (between 0.3 and 2.5 microg/ml) and decreased at higher concentrations, while adhesion on the N-terminal fragment of fibrillin-1 (rF16) was dose-dependently decreased. In addition, the rF16 fragment decreased cell adhesion to fibronectin. In conclusion, our study illustrates the important deposition of fibrillin-1 that occurs in two mechanistically distinct settings of liver fibrogenesis. Furthermore, the induction of fibrillin-1 expression by TGF-beta1 and mechanical stress, and the antiadhesive properties of fibrillin-1 fragments suggest important implications for physiological and pathological fibrillin-1 catabolism during tissue remodeling.

Interferon alfa down-regulates collagen gene transcription and suppresses experimental hepatic fibrosis in mice

The equilibrium between the production and degradation of collagen is rigorously controlled by a number of growth factors and cytokines. Interferon alfa (IFN-alpha) is now widely used for the treatment of chronic hepatitis C, which can improve serum levels of fibrotic markers and the degree of hepatic fibrosis, not only in patients who responded to therapy but also in those in whom it is ineffective. These findings may suggest that IFN-alpha possesses direct antifibrotic effects in addition to its antiviral activity. However, in contrast to IFN-gamma, which has been shown to suppress collagen gene transcription, little is known about the mechanisms responsible for the antifibrotic effects of IFN-alpha. Here, we report that IFN-alpha, when administered into transgenic mice harboring the alpha2(I) collagen gene (COL1A2) promoter sequence, significantly repressed promoter activation and prevented the progression of hepatic fibrosis induced by carbon tetrachloride injection. Transient transfection assays indicated that IFN-alpha decreased the steady-state levels of COL1A2 messenger RNA (mRNA) and inhibited basal and TGF-beta/Smad3-stimulated COL1A2 transcription in activated hepatic stellate cells (HSC). These inhibitory effects of IFN-alpha on COL1A2 transcription were exerted through the interaction between phosphorylated Stat1 and p300. Blocking of the IFN-alpha signal by overexpressing the intracellular domain-deleted IFN receptor increased basal COL1A2 transcription and abolished the inhibitory effects of IFN-alpha. In conclusion, our results indicate that IFN-alpha antagonizes the TGF-beta/Smad3-stimulated COL1A2 transcription in vitro and suppresses COL1A2 promoter activation in vivo, providing a molecular basis for antifibrotic effects of IFN-alpha.

Role of apoptosis in the remodeling of cholestatic liver injury following release of the mechanical stress

It has been known for a long time that portal fibrosis consecutive to experimental common bile duct ligation is reversible following obstacle removal, but the mechanisms involved remain unknown. We have studied the effect of bilioduodenal anastomosis and of simple biliary decompression on the remodeling of the lesion in bile duct-ligated rats. Rats were subjected to common bile duct ligation for 7 days or 14 days. Bilioduodenal anastomosis was performed after 14 days of bile duct ligation and animals sacrificed at intervals. In other animals, after 7 days or 14 days of ligation, the common bile duct was merely decompressed by bile aspiration and animals sacrificed 24 h later. Collagen deposition, alpha-smooth muscle actin expression and apoptosis were evaluated. Bile was collected and the bile acid profile assessed. After anastomosis, collagen deposition and alpha-smooth muscle actin expression decreased and were back to control values after 7 days. These parameters remained practically unchanged 24 h after biliary decompression. Bile duct ligation by itself induced apoptosis of some fibroblastic and bile ductular cells after 7 days; this was back to normal after 14 days. After anastomosis or decompression, apoptosis of both fibroblastic and bile ductular cells increased greatly and was accompanied by ultrastructural features of extracellular matrix degradation. Total bile acid content decreased after common bile duct ligation, the proportion of dihydroxylated bile acids decreasing and that of trihydroxylated bile acids increasing. Biliary decompression and anastomosis did not modify total concentration and composition of the biliary bile acid pool. In summary, we show that mere biliary decompression, by relieving the mechanical stress, is as effective as bilioduodenal anastomosis to induce apoptosis of portal cells that likely triggers portal fibrosis regression.

Review article: indicators and predictors of response to anti-viral therapy in chronic hepatitis C

The complications of chronic hepatitis C, including cirrhosis and hepatocellular carcinoma, are expected to increase dramatically world-wide over the next 10-20 years. Immunomodulatory/anti-viral therapy, employing interferon alfa both alone and in combination with ribavirin, affords the only effective treatment for hepatitis C. Accurate early prediction of response to interferon therapy may decrease or eliminate unnecessary or ineffective treatment, permit greater flexibility in tailoring therapy on an individual basis, and enhance the cost-effectiveness of treatment. Liver biopsy provides valuable information about the baseline severity and subsequent progression of hepatitis C. Severe fibrosis or cirrhosis on the pre-treatment liver biopsy is associated with decreased response rates. The measurement of viral RNA levels and genotyping may be used to optimize individual patient treatment. Genotype non-1 and a low viral load are the most significant pre-treatment indicators of sustained virological response. The most reliable predictor of a poor virological response is continued seropositivity for viral RNA during therapy. Therefore, a decision to stop or continue treatment can be based on a positive viral RNA test at 12 weeks for interferon-naive patients receiving interferon or pegylated interferon therapy.

[Role of interferons in the treatment of hepatitis B and hepatitis C virus infections]

BACKGROUND

Since the discovery of hepatitis C (HCV), the efficacy of treatment has significantly progressed using standard mono-therapy: with Interferon alpha (IFN) during six months we obtained approximately 10% sustained response and currently with the association of pegylated IFN and Ribavirin a 55% sustained response was achieved.

CURRENT POSITION AND MAJOR POINTS

HCV infection continues to present therapeutic problems which have not entirely been solved, mainly related to clinical and biological tolerance, and non-responders. Moreover, the care of patients with extra-hepatic localization, cirrhotic patients, as well as therapeutic problems of co-infected HIV-HCV patients. As regards hepatitis B (HBV) new effective treatments against this virus have appeared, IFN then nucleoside analogs, some of which are available in France (i.e. lamivudine, adefovir, dipovoxil). The main objective of chronic hepatitis B treatment is to obtain the complete inhibition of the HBV virus by Hbe-antigen antibody seroconversion which would therefore significantly increase patient survival. In this article the advantages and disadvantages of the different treatments are assessed.

FUTURE PERSPECTIVES

Despite the considerable and rapid progress obtained in the therapeutic treatment of infection due to HCV and HBV a number of unknown factors remain, which warrants further trials, in particular to evaluate the efficacy as well as the tolerance of the antiviral agent association.

Future research directions in idiopathic pulmonary fibrosis: summary of a National Heart, Lung, and Blood Institute working group

Idiopathic pulmonary fibrosis (IPF) is an insidious inflammatory fibroproliferative disease whose cause and course before diagnosis are unknown, and for which existing treatments are of limited benefit. The National Heart, Lung, and Blood Institute convened a working group to develop specific recommendations for future IPF research. Inflammatory and immune processes are involved in IPF pathogenesis, and current therapeutic strategies are aimed at suppressing the inflammation. Recent data suggest that the molecular processes underlying the fibrogenesis may provide new opportunities for therapeutic intervention. Specific areas of future research recommended by the working group include studies to elucidate the etiology of IPF, to develop novel diagnostic techniques and molecular diagnostics, to establish a program for identification of molecular targets for IPF treatment and identification and generation of agonists or antagonists that inhibit fibrogenesis, to foster investigations that couple the use of new technologies (e.g., laser capture microdissection, microarrays, and mass spectroscopic analysis of proteins) with data from the human genome project, to establish a national consortium of Clinical Centers of Excellence to conduct coordinated clinical and laboratory studies of well-characterized patients and patient-derived materials, and to stimulate research to develop animal models of persistent and progressive pulmonary fibrosis for evaluation of new intervention approaches.

Scoring of chronic hepatitis

Grading of the severity of chronic hepatitis and staging of its structural consequences are widely used in clinical trials of therapy and in research. Simple and complex methods are available. Intra- and interobserver variation can be reduced but not eliminated, because grading and staging are essentially subjective. The data are categorical rather than numerical and must be treated accordingly. Morphometry of fibrous tissue offers a different approach to biopsy assessment.

Cellular retinol-binding protein-1 expression and modulation during in vivo and in vitro myofibroblastic differentiation of rat hepatic stellate cells and portal fibroblasts

Cellular retinol-binding protein-1 (CRBP-1) is involved in vitamin A metabolism because it mediates both retinol esterification to retinyl esters and retinol oxidation to retinal and retinoic acid. CRBP-1 is highly expressed in the liver, particularly in hepatic stellate cells (HSC). In this study, we investigated the liver expression of CRBP-1 during experimental fibrogenesis. We also studied the regulation of CRBP-1 expression in cultured HSC and portal fibroblasts, two fibroblastic cell types involved in liver fibrogenesis. Fibrosis was induced in rats by carbon tetrachloride (CCl(4)) or bile duct ligation. Immunohistochemical staining was performed for CRBP-1 and alpha-smooth muscle (SM) actin, an activation marker of fibrogenic cells. CRBP-1 and alpha-SM actin expression was studied by Western blotting and/or Northern blot in primary cultures of HSC isolated by conventional methods and in portal fibroblasts that were obtained by outgrowth from the biliary tree after enzymatic digestion. In normal liver, contrary to HSC, portal fibroblasts did not express CRBP-1. After CCl(4) injury, CRBP-1 expression was maintained in myofibroblastic alpha-SM actin-positive HSC. After bile duct ligation, portal fibroblasts (which proliferated around ductular structures) acquired expression of both CRBP-1 and alpha-SM actin. During HSC activation in culture, CRBP-1 expression gradually increased until Day 5 when alpha-SM actin expression was obvious. Cultured portal fibroblasts developed both CRBP-1 and alpha-SM actin expression. In both cell populations, transforming growth factor-beta 1 treatment increased CRBP-1 expression. Thus, in normal liver, CRBP-1 expression was different among fibroblastic cells, a finding that adds to the concept of heterogeneity of liver fibrogenic cells. Furthermore, during myofibroblastic differentiation, HSC that lost their stores of retinol maintained a high level of CRBP-1 expression, whereas portal fibroblasts acquired CRBP1 expression. Together, these data suggest a correlation between CRBP-1 expression and myofibroblastic differentiation.

Increased oxidative stress in dimethylnitrosamine-induced liver fibrosis in the rat: effect of N-acetylcysteine and interferon-alpha

Oxidative stress may represent a common link between chronic liver damage and hepatic fibrosis. Antioxidants and interferon seem to protect against hepatic stellate cell (HSC) activation and liver fibrosis. This study evaluated (1) the effect of the profibrotic agent dimethylnitrosamine (DMN) on the hepatic oxidative balance in the rat; (2) the role played by the antioxidant agent N-acetylcysteine (NAC); and (3) the antifibrotic effects of two different types of interferon-alpha: recombinant alpha-2b (rIFN-alpha) and leukocyte alpha (LeIFN-alpha). Five groups of rats received: (1) saline; (2) DMN; (3) DMN + NAC; (4) DMN + rIFN-alpha; and (5) DMN + LeIFN-alpha. Oxidative balance was evaluated by hepatic glutathione, TBARs, protein carbonyl, and sulfhydryl determination. Fibrosis was determined by hepatic hydroxyproline content and fibronectin (FN) staining (immunohistochemistry). DMN rats showed a diffuse FN deposition, an impaired oxidative balance, and higher hepatic hydroxyproline levels compared to that of controls. NAC administration significantly reduced FN deposition, increased hepatic glutathione, and decreased TBARs and protein carbonyls. Administration of IFN-alpha exerted different effects according to the type used. Both IFNs decreased FN deposition; however, LeIFN-alpha significantly improved histology and oxidative parameters compared to those of untreated DMN and rats treated with rIFN-alpha. This study shows the role of free radicals in this model of hepatic fibrosis; the protective effect of NAC against liver fibrosis; and the antifibrotic effect exerted by IFN-alpha (particularly LeIFN-alpha) independent of its antiviral activity.

Changes in histological lesions and serum fibrogenesis markers in chronic hepatitis C patients non-responders to interferon alpha

BACKGROUND/AIMS

The aim of this study was to evaluate the changes in histological lesions and serum N-terminal peptide of type III procollagen (PIIINP) and hyaluronate (HA) levels in virologic non-responder patients treated by Interferon alpha (IFNalpha).

METHODS

We enrolled 183 patients treated by IFNalpha and 56 controls, all with paired biopsy specimens. Yearly liver fibrosis progression was estimated before and during a follow-up of 1 year.

RESULTS

By contrast to sustained responders, non-responders (n = 105) did not achieve improvement of histological scores after therapy. Their yearly fibrosis progression rate was similar before and during follow-up (0.18, 95%CI: 0.16-0.20, vs 0.26 (95%CI: 0.12-0.40) fibrosis units/year, NS), and was not different in controls (0.17, 95%CI: 0.06-0.27). The levels of PIIINP and hyaluronate (HA) remained unchanged during follow-up. Histological improvement was observed for the second biopsy in 25% of non-responders, but also in 23% of controls. This improvement was not correlated with decrease of ALT level, viral load, PIIINP, or HA.

CONCLUSIONS

Our results suggest that IFNalpha therapy is unable to decrease PIIINP or HA levels and cannot improve the histological outcome in virologic non-responder patients. The histological improvement observed in a subset of patients may be linked to sample fluctuation or lack of reproducibility of histological scores.

Hepatic fibrosis. Pathogenesis and principles of therapy

There has been great progress made in our understanding of the cellular mechanisms of hepatic fibrosis. The recognition that the hepatic stellate cell, (formerly know as lipocyte, Ito, or fat-storing cell), played a central role in the fibrotic response was key to our understanding. Stellate cells undergo a process known as activation, in response to any insult. Activation is a broad phenotypic response, characterized by distinct functional changes in proliferation, fibrogenesis, contractility, cytokine secretion, and matrix degradation. Insights gained into the molecular regulations of stellate cell activation may lead to new antifibrotic therapies, which may reduce morbidity and mortality in patients with chronic liver injury.

Liver fibrosis assessment with semiquantitative indexes and image analysis quantification in sustained-responder and non-responder interferon-treated patients with chronic hepatitis C

BACKGROUND/AIMS

The effect of interferon on the reduction of liver fibrosis is controversial. We aimed to compare semiquantitative methods with a quantitative digital image analysis system to assess liver fibrosis in biopsies from patients with chronic hepatitis and different responses to interferon.

METHODS

We studied 98 liver biopsies with chronic hepatitis C before and after recombinant interferon alfa-2 treatment, using conventional histological assessment, grading of histological activity, scoring/staging of fibrosis (Knodell and Scheuer), and quantification of fibrosis with image analysis (FibroQuant).

RESULTS

Sustained-responders to interferon showed a significant reduction in histological lesions and in their Knodell and Scheuer activity indexes. The semiquantitative systems showed no reduction in fibrosis. The FibroQuant application showed a significant reduction in porto-periportal and septal areas among sustained-responders (P < 0.001) and non-responders (P < 0.05), and in porto-periportal and septal fibrosis areas only in sustained-responders (P < 0.001), whereas the percentage of fibrosis increased in non-responders (P < 0.001).

CONCLUSIONS

The Scheuer system is useful for the daily evaluation of fibrosis, but the FibroQuant application provides more objective data on the anti-fibrogenic effects of interferon, which include a reduction in the porto-periportal area in sustained-responders and non-responders, accompanied by a reduction in the area of fibrosis only when the viral replication has ceased.

Effect of interferon-alpha on experimental septal fibrosis of the liver - study with a new model

Interferon-alpha is used in antiviral therapy in humans, mainly for viral hepatitis B and C. An anti-fibrotic effect of interferon has been postulated even in the absence of anti-viral response, which suggests that interferon directly inhibits fibrogenesis. Rats infected with the helminth Capillaria hepatica regularly develop diffuse septal fibrosis of the liver, which terminates in cirrhosis 40 days after inoculation. The aim of this study was to test the anti-fibrotic effect of interferon in this experimental model. Evaluation of fibrosis was made by three separate methods: semi-quantitative histology, computerized morphometry and hydroxyproline measurements. Treatment with interferon-alpha proved to inhibit the development of fibrosis in this model, especially when doses of 500,000 and 800,000 IU were used for 60 days. Besides confirming the anti-fibrotic potential of interferon-alpha on a non-viral new experimental model of hepatic fibrosis, a clear-cut dose-dependent effect was observed.