Cytokeratin expression as an aid to diagnosis in medical liver biopsies

Establishment and validation of a nomogram containing cytokeratin fragment antigen 21-1 for the differential diagnosis of intrahepatic cholangiocarcinoma and hepatocellular carcinoma

Background

Our study aimed to develop a nomogram incorporating cytokeratin fragment antigen 21-1 (CYFRA21-1) to assist in differentiating between patients with intrahepatic cholangiocarcinoma (ICC) and hepatocellular carcinoma (HCC).

Methods

A total of 487 patients who were diagnosed with ICC and HCC at Qilu Hospital of Shandong University were included in this study. The patients were divided into a training cohort and a validation cohort based on whether the data collection was retrospective or prospective. Univariate and multivariate analyses were employed to select variables for the nomogram. The discrimination and calibration of the nomogram were evaluated using the area under the receiver operating characteristic curve (AUC) and calibration plots. Decision curve analysis (DCA) was used to assess the nomogram's net benefits at various threshold probabilities.

Results

Six variables, including CYFRA21-1, were incorporated to establish the nomogram. Its satisfactory discriminative ability was indicated by the AUC (0.972 for the training cohort, 0.994 for the validation cohort), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) values. The Hosmer-Lemeshow test and the calibration plots demonstrated favorable consistency between the nomogram predictions and the actual observations. Moreover, DCA revealed the clinical utility and superior discriminative ability of the nomogram compared to the model without CYFRA21-1 and the model consisting of the logarithm of alpha-fetoprotein (Log AFP) and the logarithm of carbohydrate antigen 19-9 (Log CA19-9). Additionally, the AUC values suggested that the discriminative ability of Log CYFRA21-1 was greater than that of the other variables used as diagnostic biomarkers.

Conclusions

This study developed and validated a nomogram including CYFRA21-1, which can aid clinicians in the differential diagnosis of ICC and HCC patients.

Quantitative Evaluation by Digital Pathology of Immunohistochemical Expression of CK7, CK19, and EpCAM in Advanced Stages of NASH

(1) Background: Nonalcoholic Steatohepatitis/Nonalcoholic Fatty Liver Disease (NASH/NAFLD) is the most recurrent chronic liver disease. NASH could present with a cholestatic (C) or hepatic (H) pattern of damage. Recently, we observed that increased Epithelial Cell Adhesion Molecule (EpCAM) expression was the main immunohistochemical feature to distinguish C from H pattern in NASH. (2) Methods: In the present study, we used digital pathology to compare the quantitative results of digital image analysis by QuPath software (Q-results), with the semi-quantitative results of observer assessment (S-results) for cytokeratin 7 and 19, (CK7, CK19) as well as EpCAM expression. Patients were classified into H or C group on the basis of the ratio between alanine transaminase (ALT) and alkaline phosphatase (ALP) values, using the "R-ratio formula". (3) Results: Q- and S-results showed a significant correlation for all markers (p < 0.05). Q-EpCAM expression was significantly higher in the C group than in the H group (p < 0.05). Importantly ALP, an indicator of hepatobiliary disorder, was the only biochemical parameter significantly correlated with Q-EpCAM. Instead, Q-CK7, but not Q-CK19, correlated only with γGlutamyl-Transferase (γGT). Of note, Stage 4 fibrosis correlated with Q-EpCAM, Q-CK19, and ALP but not with γGT or ALT. Conclusions: Image analysis confirms the relation between cholestatic-like pattern, associated with a worse prognosis, with increased ALP values, EpCAM positive biliary metaplasia, and advanced fibrosis. These preliminary data could be useful for the implementation of AI algorithms for the assessment of cholestatic NASH.

Analysis of clinicopathologic and imaging features of dual-phenotype hepatocellular carcinoma

Dual-phenotype hepatocellular carcinoma (DPHCC) is a new subtype of hepatocellular carcinoma (HCC). This study aimed to investigate the relationship between the computerized tomography scan (CT) imaging and clinicopathologic features of DPHCC. The CT imaging and clinicopathologic data of 97 HCC cases who underwent radical resection were collected retrospectively. The CT imaging feature was evaluated by the ratio of the average CT value of tumor to liver (TLR) in the plain scan, arterial, portal vein and delayed phases. The association between CT imaging and clinicopathologic features was analyzed using the t-test or chi-square test. Univariate and multivariate recurrence-free survival (RFS) analysis and overall survival (OS) were performed. The positive rates of cytokeratin 7 (CK7) and CK19 were 35.1% and 20.6% respectively. The positive rate of CK19 was significantly higher in cases with age < 47 years (P = 0.005), tumor diameter > 4 cm (P = 0.016) or AFP ≥ 400 ng/ml (P = 0.007). The TLR in the portal vein phase was significantly lower in CK19 positive group (P = 0.024). The recurrence risk was significantly higher in cases with CK19 positive (HR: 2.17, 95% CI 1.16 to 4.04, P = 0.013), tumor diameter > 4 cm (HR: 2.05, 95% CI 1.11 to 3.78, P = 0.019), AFP ≥ 400 ng/ml (HR: 2.50, 95% CI 1.37 to 4.54, P = 0.002) or CA199 ≥ 37 U/ml (HR: 2.23, 95% CI 1.12 to 4.42, P = 0.020). However, imaging features, pathological subtype, CK7 or CK19 expression were not significantly related to HCC OS in the univariate and multivariate analysis (all P > 0.05). The expression of CK19 may be associated with the enhancement feature of the portal vein phase CT image, and CK19 positive may suggest a worse RFS.

Spatially segregated defects and IGF1-responsiveness of hilar and peripheral biliary organoids from a model of Alagille syndrome

BACKGROUND & AIMS

Alagille syndrome (ALGS) manifests with peripheral intrahepatic bile duct (IHBD) paucity, which can spontaneously resolve. In a model for ALGS, Jag1Ndr/Ndr mice, this occurs with distinct architectural mechanisms in hilar and peripheral IHBDs. Here, we investigated region-specific IHBD characteristics and addressed whether IGF1, a cholangiocyte mitogen that is downregulated in ALGS and in Jag1Ndr/Ndr mice, can improve biliary outcomes.

METHODS

Intrahepatic cholangiocyte organoids (ICOs) were derived from hilar and peripheral adult Jag1+/+ and Jag1Ndr/Ndr livers (hICOs and pICOs, respectively). ICOs were grown in Matrigel or microwell arrays, and characterized using bulk RNA sequencing, immunofluorescence, and high throughput analyses of nuclear sizes. ICOs were treated with IGF1, followed by analyses of growth, proliferation, and death. CellProfiler and Python scripts were custom written for image analyses. Key results were validated in vivo by immunostaining.

RESULTS

Cell growth assays and transcriptomics demonstrated that Jag1Ndr/Ndr ICOs were less proliferative than Jag1+/+ ICOs. IGF1 specifically rescued survival and growth of Jag1Ndr/Ndr pICOs. Jag1Ndr/Ndr hICOs were the least proliferative, with lower Notch signalling and an enrichment of hepatocyte signatures and IGF uptake/transport pathways. In vitro (Jag1Ndr/Ndr hICOs) and in vivo (Jag1Ndr/Ndr hilar portal tracts) analyses revealed ectopic HNF4a+ hepatocytes.

CONCLUSIONS

Hilar and peripheral Jag1Ndr/Ndr ICOs exhibit differences in Notch signalling status, proliferation, and cholangiocyte commitment which may result in cholangiocyte-to-hepatocyte transdifferentiation. While Jag1Ndr/Ndr pICOs can be rescued by IGF1, hICOs are unresponsive, perhaps due to their hepatocyte-like state and/or expression of IGF transport components. IGF1 represents a potential therapeutic for peripheral bile ducts.

An Update on the Role of Immunohistochemistry in the Evaluation of Pancreatic/Liver/Gastrointestinal Luminal Tract Disorders

CONTEXT.—

Immunohistochemistry serves as an ancillary diagnostic tool for a wide variety of neoplastic and nonneoplastic disorders, including infections, workup of inflammatory conditions, and subtyping neoplasms of the pancreas/liver/gastrointestinal luminal tract. In addition, immunohistochemistry is also used to detect a variety of prognostic and predictive molecular biomarkers for carcinomas of the pancreas, liver, and gastrointestinal luminal tract.

OBJECTIVE.—

To highlight an update on the role of immunohistochemistry in the evaluation of pancreatic/liver/gastrointestinal luminal tract disorders.

DATA SOURCES.—

Literature review and authors' research data and personal practice experience were used.

CONCLUSIONS.—

Immunohistochemistry is a valuable tool, assisting in the diagnosis of problematic tumors and benign lesions of the pancreas, liver, and gastrointestinal luminal tract, and also in the prediction of prognosis and therapeutic response for carcinomas of the pancreas, liver, and gastrointestinal luminal tract.

A Kaleidoscope of Keratin Gene Expression and the Mosaic of Its Regulatory Mechanisms

Keratins are a family of intermediate filament-forming proteins highly specific to epithelial cells. A combination of expressed keratin genes is a defining property of the epithelium belonging to a certain type, organ/tissue, cell differentiation potential, and at normal or pathological conditions. In a variety of processes such as differentiation and maturation, as well as during acute or chronic injury and malignant transformation, keratin expression undergoes switching: an initial keratin profile changes accordingly to changed cell functions and location within a tissue as well as other parameters of cellular phenotype and physiology. Tight control of keratin expression implies the presence of complex regulatory landscapes within the keratin gene loci. Here, we highlight patterns of keratin expression in different biological conditions and summarize disparate data on mechanisms controlling keratin expression at the level of genomic regulatory elements, transcription factors (TFs), and chromatin spatial structure.

Novel histological scoring for predicting disease outcome in primary sclerosing cholangitis

Background

Primary sclerosing cholangitis (PSC) is a progressive cholestatic liver disease that may lead to liver cirrhosis or cholangiocarcinoma. Liver histology and fibrosis stage are predictive markers of disease progression, and histological cirrhosis is defined as a significant endpoint. PSC‐specific histological scoring methods are lacking at present. We aimed to develop a tailored classification system for PSC, the PSC histoscore, based on histological features associated with disease progression.

Methods

In total, 300 PSC patients diagnosed between 1988 and 2018 were enrolled; their data were collected from the PSC registry (Helsinki University Hospital), and liver specimens were obtained from the Biobank of Helsinki. Five histological features included in the adapted Nakanuma scoring system and three additional parameters typical for PSC histology were evaluated and compared with the clinical and laboratory data. A compound endpoint consisting of liver transplantation, development of cholangiocarcinoma, or death was used as outcome measurement.

Results

Stage (fibrosis, bile duct loss, ductular reaction, and chronic cholestasis) and grade (portal inflammation, portal edema, hepatitis activity, and cholangitis activity) parameters were found to be independent predictive risk factors for the compound endpoint (P < 0.001). High disease grade (2–6) and stage (2–4) better correlated with clinical endpoints when evaluated with the PSC histoscore system compared to the adapted Nakanuma classification. The risk for disease progression in sequential endoscopic retrograde cholangiography (ERC) examinations was increased with elevated total PSC histoscores.

Conclusion

The PSC histoscore is a novel histological classification system for PSC. Our findings support the applicability of liver histology as a marker for disease progression.

A cholestatic pattern predicts major liver-related outcomes in patients with non-alcoholic fatty liver disease

BACKGROUND & AIMS

NAFLD patients usually have an increase in AST/ALT levels, but cholestasis can also be observed. We aimed to assess in subjects with NAFLD the impact of the (cholestatic) C pattern on the likelihood of developing major liver-related outcomes (MALO).

METHODS

Five hundred and eighty-two consecutive patients with biopsy-proven NAFLD or a clinical diagnosis of NAFLD-related compensated cirrhosis were classified as hepatocellular (H), C and mixed (M) patterns, by using the formula (ALT/ALT Upper Limit of Normal-ULN)/(ALP/ALP ULN). MALO were recorded during follow-up. An external cohort of 1281 biopsy-proven NAFLD patients was enrolled as validation set.

RESULTS

H, M and C patterns were found in 153 (26.3%), 272 (46.7%) and 157 (27%) patients respectively. During a median follow-up of 78 months, only 1 (0.6%) patient with H pattern experienced MALO, whilst 15 (5.5%) and 38 (24.2%) patients in M and C groups had MALO. At multivariate Cox regression analysis, age >55 years (HR 2.55, 95% CI 1.17-5.54; p = .01), platelets <150 000/mmc (HR 0.14, 95% CI 0.06-0.32; p < .001), albumin <4 g/L(HR 0.62, 95% CI 0.35-1.08; p = .09), C versus M pattern (HR 7.86, 95% CI 1.03-60.1; p = .04), C versus H pattern(HR 12.1, 95% CI 1.61-90.9; p = .01) and fibrosis F3-F4(HR 35.8, 95% CI 4.65-275.2; p < .001) were independent risk factors for MALO occurrence. C versus M pattern(HR 14.3, 95% CI 1.90-105.6; p = .008) and C versus H pattern (HR 15.6, 95% CI 2.10-115.1; p = .0068) were confirmed independently associated with MALO occurrence in the validation set. The immunohistochemical analysis found a significantly higher prevalence of moderate-high-grade ductular metaplasia combined with low-grade ductular proliferation in C pattern when compared with the biochemical H pattern. Gene expression analysis showed a lower expression of NR1H3, RXRα and VCAM1 in patients with the C pattern.

CONCLUSIONS

The presence of a cholestatic pattern in patients with NAFLD predicts a higher risk of MALO independently from other features of liver disease.

Patient-Derived Avatar Mouse Model to Predict the Liver Immune Homeostasis of Long-Term Stable Liver Transplant Patients

Although rejection or tolerance can occur in liver transplantation (LT) patients, there are no reliable non-invasive methods for predicting immune homeostasis. In this study, we developed a humanized mouse model to predict liver immune homeostasis in patients who underwent LT. The patient-derived avatar model was developed by injecting peripheral blood mononuclear cells from healthy controls (HCs) or LT patients with stable, rejection, or tolerance into NOD.Cg-Prkdc^scidIL2rg^tm1Wjl/SzJ (NSG) mice, followed by injection of human hepatic stellate cells and Carbone tetrachloride (CCl₄). After 7 weeks, the patient’s T-cell engraftment and liver inflammation in the avatar model were evaluated and compared with the liver histology of LT patients. Changes in liver inflammation following treatment with tacrolimus and/or biguanide derivatives were also examined. The C-X-C Motif Chemokine Receptor 3 (CXCR3)-dependently engrafted patient T cells led to differences in liver inflammation in our model according to the status of LT patients. The livers of avatar models from rejection patients had severe inflammation with more T helper 17 cells and fewer regulatory T cells compared to those of models from tolerance and HCs showing only mild inflammation. Moreover, our model classified stable post-LT patients into severe and mild inflammation groups, which correlated well with liver immunity in these patients. Our models revealed alleviation of inflammation after combination treatment with tacrolimus and biguanide derivatives or monotherapy. Consequently, using our new patient-derived avatar model, we predicted liver immune homeostasis in patients with stable LT without biopsy. Moreover, our avatar model may be useful for preclinical analysis to evaluate treatment responses while reducing risks to patients.

Serum level of cytokeratin 19 as a diagnostic and prognostic marker in patients with HCV-related hepatocellular carcinoma

Background

The heterogeneous nature of human hepatocellular carcinoma (HCC) impedes both treatment strategies and prognostic predictions. Several markers have been proposed for the diagnosis of HCC. Cytoskeleton-associated proteins have been known as cellular integrators in neoplasm formation. Hepatic progenitor cells are thought to express alpha-fetoprotein (AFP) and hematopoietic as well as biliary markers such as cytokeratin 19 (CK 19) and cytokeratin 7. The aim of this study was to verify the role of serum CK 19 alone or in combination with AFP as a diagnostic marker of HCC and to assess the changes in its levels after ablation of HCV-related HCC to evaluate its role as a predictor marker for recurrence of HCC after ablation. The study was conducted on 102 HCV-related cirrhotic patients categorized into three different groups according to the clinical, laboratory, and radiological evaluation: group I—62 patients with early or intermediate HCC who underwent locoregional intervention, group II—20 patients with advanced HCC not fit for any intervention apart from best supportive treatment, and group III—20 cirrhotic patients with no evidence of HCC as proved by two imaging techniques.

Results

The mean serum levels of CK 19 were 6.5 ± 5.7, 10.5 ± 12.5, and 6.8 ± 2.8 ng/ml in groups I, II, and III, respectively, with no significant difference between groups. Sensitivity, specificity, positive, and negative predictive values of combined AFP and human CK 19 at cutoff levels of 25.5 ng/ml and 6.25 ng/ml were 93.9%, 45%, 87.5%, and 64.3%, respectively. In group I patients, CK 19 levels were comparable in patients with ablated focal lesion and those who did not at baseline; then, it was significantly higher in ablated patients than in patients with residual tumor 1 and 6 months after the intervention.

Conclusions

Combination of both AFP and CK 19 levels could increase the diagnostic accuracy of suspected HCCs. CK 19 levels are good predictors of ablation/recurrence in patients who underwent interventional procedures minimizing the need for follow-up imaging modalities.

Early histopathologic changes in primary biliary cholangitis: does 'minimal change' primary biliary cholangitis exist? A pathologist's view

Primary biliary cholangitis (PBC), formerly known as primary biliary cirrhosis, is an autoimmune, slowly progressive, cholestatic liver disease characterized by nonsuppurative destructive cholangitis, and interlobular bile duct destruction. Necroinflammatory activities of the hepatic parenchyma and limiting plates of milder form along with late liver fibrosis may develop. Serum liver tests include elevated serum alkaline phosphatase along with a positive antimitochondrial antibody (AMA) in nearly 95% of patients. Liver biopsies are an important confirmatory and staging tool and are additionally very helpful when AMA is negative. More specifically, the earliest changes in liver biopsy suspicious for PBC can be detected, namely loss of the canals of Hering (CoH), as proposed by various authors recently. CoH loss has been described as an early feature of PBC. We focus on early histologic features of PBC, investigating through the literature the possible role of 'minimal change' supporting the clinical diagnosis of PBC, even in the absence of characteristic granulomatous duct destructive lesions.

Keratin 7 expression in hepatic cholestatic diseases

We evaluated keratin 7 (K7) hepatocellular expression in 92 patients with common types of acute and chronic cholestatic diseases caused by bile duct obstruction/destruction or parenchymal lesions [acute hepatitis (n=20), mixed/pure cholestasis (n=16), primary biliary cholangitis-PBC (n=35), primary sclerosing cholangitis-PSC (n=10), vanishing bile duct syndrome (n=3), complete large bile duct obstruction due to space-occupying lesions (n=8)]. K7 immunohistochemical hepatocellular expression and ductular reaction (DR) were semi-quantitatively assessed. Results were correlated with liver enzyme serum levels, cholestasis type, histological features, hepatocellular Ki67 labelling index (LI) and HepPar1 expression. Hepatocellular K7 expression was detected in 87% (81/92) cases and in all cholestatic disease types with lowest incidence in pure/mixed cholestasis and highest in incomplete bile duct obstruction (iBDO), reaching 100% in PSC. K7-positive hepatocytes had low Ki67 LI (0-5%) retaining HepPar1 expression, irrespective of disease type. PSC cases had high K7 hepatocellular expression even with intact bile ducts, a feature that may aid differential diagnosis of cholestatic syndromes. K7 hepatocellular expression significantly correlated with cholestasis type, bile duct loss and fibrosis stage. It was higher in milder acute cholestatic hepatitis showing inverse correlation with hepatocyte proliferation and serum transaminase levels. In iBDO, younger age independently correlated with high K7 expression, while serum GGT levels showed a nearly significant correlation. Correlation with DR findings implied that K7-positive hepatocytes may result through metaplasia. In conclusion, K7 hepatocellular expression is a sensitive though non-specific marker of cholestasis. It may represent a cytoprotective reaction of resting hepatocytes in cholestasis of longer duration especially in younger patients.

Chronic cholestasis detection by a novel tool: automated analysis of cytokeratin 7-stained liver specimens

Background

The objective was to build a novel method for automated image analysis to locate and quantify the number of cytokeratin 7 (K7)-positive hepatocytes reflecting cholestasis by applying deep learning neural networks (AI model) in a cohort of 210 liver specimens. We aimed to study the correlation between the AI model’s results and disease progression. The cohort of liver biopsies which served as a model of chronic cholestatic liver disease comprised of patients diagnosed with primary sclerosing cholangitis (PSC).

Methods

In a cohort of patients with PSC identified from the PSC registry of the University Hospital of Helsinki, their K7-stained liver biopsy specimens were scored by a pathologist (human K7 score) and then digitally analyzed for K7-positive hepatocytes (K7%area). The digital analysis was by a K7-AI model created in an Aiforia Technologies cloud platform. For validation, values were human K7 score, stage of disease (Metavir and Nakunuma fibrosis score), and plasma liver enzymes indicating clinical cholestasis, all subjected to correlation analysis.

Results

The K7-AI model results (K7%area) correlated with the human K7 score (0.896; p < 2.2e^− 16). In addition, K7%area correlated with stage of PSC (Metavir 0.446; p < 1.849e^− 10 and Nakanuma 0.424; p < 4.23e^− 10) and with plasma alkaline phosphatase (P-ALP) levels (0.369, p < 5.749e^− 5).

Conclusions

The accuracy of the AI-based analysis was comparable to that of the human K7 score. Automated quantitative image analysis correlated with stage of PSC and with P-ALP. Based on the results of the K7-AI model, we recommend K7 staining in the assessment of cholestasis by means of automated methods that provide fast (9.75 s/specimen) quantitative analysis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13000-021-01102-6.

Liver injury after small bowel resection is prevented in obesity-resistant 129S1/SvImJ mice

Intestinal failure-associated liver disease is a major morbidity associated with short bowel syndrome. We sought to determine if the obesity-resistant mouse strain (129S1/SvImJ) conferred protection from liver injury after small bowel resection (SBR). Using a parenteral nutrition-independent model of resection-associated liver injury, C57BL/6J and 129S1/SvImJ mice underwent a 50% proximal SBR or sham operation. At postoperative week 10, hepatic steatosis, fibrosis, and cholestasis were assessed. Hepatic and systemic inflammatory pathways were evaluated using oxidative markers and abundance of tissue macrophages. Potential mechanisms of endotoxin resistance were also explored. Serum lipid levels were elevated in all mouse lines. Hepatic triglyceride levels were no different between mouse strains, but there was an increased accumulation of free fatty acids in the C57BL/6J mice. Histological and serum markers of hepatic fibrosis, steatosis, and cholestasis were significantly elevated in resected C57BL/6J SBR mice as well as oxidative stress markers and macrophage recruitment in both the liver and visceral white fat in C57BL/6J mice compared with sham controls and the 129S1/SvImJ mouse line. Serum endotoxin levels were significantly elevated in C57BL/6J mice with significant elevation of hepatic TLR4 and reduction in PPARα expression levels. Despite high levels of serum lipids, 129S1/SvImJ mice did not develop liver inflammation, fibrosis, or cholestasis after SBR, unlike C57BL/6J mice. These data suggest that the accumulation of hepatic free fatty acids as well as increased endotoxin-driven inflammatory pathways through PPARα and TLR4 contribute to the liver injury seen in C57BL/6J mice with short bowel syndrome.NEW & NOTEWORTHY Unlike C57BL/6 mice, the 129S1/SvImJ strain is resistant to liver inflammation and injury after small bowel resection. These disparate outcomes are likely due to the accumulation of hepatic free fatty acids as well as increased endotoxin-driven inflammatory pathways through PPARα and TLR4 in C57BL/6 mice with short bowel syndrome.

Immunohistochemical evaluation of hepatic progenitor cells in different types of feline liver diseases

Hepatic progenitor cells are periportally resident cells capable of differentiating into mature hepatocytes or cholangiocytes to ensure hepatic regeneration. This reaction is termed a ductular reaction. In the present study, regenerative response of the feline liver to different hepatic diseases was investigated immunohistochemically. Regeneration of the liver through hepatocellular replication and proliferation of progenitor cell compartment were comparatively evaluated. Histological and immunohistochemical stainings were conducted on feline liver samples (n=40) representing various hepatobiliary diseases. Cytokeratin (CK) 7, CK19, Proliferating cell nuclear antigen (PCNA), Ki67, and Human hepatocyte marker 1 (Hep Par-1) were used. The presence of progenitor cells within feline livers was proved, both as passive cells in normal liver and as active cells (ductular reaction) in hepatic lesions. CK7 was found to be a suitable antibody for immunohistochemically detecting feline progenitor cells. In acute events, regeneration was predominantly shaped by the division of hepatocytes. In chronic events and severe acute events, hepatocytes lost their ability to divide and regeneration mainly occurred through progenitor cells. Location of the ductular reaction varied between different hepatic diseases. Parenchymal ductular reaction was detected in fulminant hepatitis, chronic hepatitis, hepatocellular lipidosis and metastatic lymphoma, whereas septal ductular reaction was detected in chronic hepatitis and metastatic lymphoma. Ductular reaction exhibited positive staining for Hep Par-1 in chronic and severe acute events. This study indicates the major role played by hepatic progenitor cells in regeneration of the feline liver. Moreover, it shows how the activation pattern of ductular reaction varies according to the hepatobiliary disease type.

Nodular Regenerative Hyperplasia: Expression Pattern of Glutamine Synthetase and a Potential Role for Hepatic Progenitor Cells

Nodular regenerative hyperplasia (NRH) is one of the most frequent causes of noncirrhotic intrahepatic hypertension, but is a difficult histologic diagnosis. The expression of glutamine synthetase (GS) and cytokeratin 7 (CK7) has been reported to be increased in other regenerative/vascular conditions, while CK7 and BerEP4 are also markers of hepatic progenitor cells. The aims of this study were to investigate the use of GS, CK7, and BerEP4 as the potential markers for NRH. This is a retrospective case series of NRH at Centre Hospitalier de l'Universite de Montreal between 1993 and 2013. Normal liver from partial hepatectomies for tumors were used as controls. GS, CK7, CK19, and BerEP4 immunohistochemical stains were performed on all specimens. Immunohistochemical staining patterns were scored from 0 to 3+. NRH was identified in 46 samples obtained from 26 patients. Liver chemistry profile was cholestatic in 45% of the patients. In 93% of the NRH cases, there was abnormal zone 2 expression of GS. Weak panacinar GS staining was seen in all the NRH cases. Aberrant CK7 expression was present in all cases of NRH, but were not associated with cholestasis. BerEP4 was overexpressed in 47% of the NRH cases (P<0.05); all cases with diffuse BerEP4 staining also showed extensive CK7 expression (P<0.01). NRH showed increased immunohistochemical GS staining that may support its morphologic diagnosis. Our findings suggest that there is an activation of hepatic progenitor cells in NRH.

Biliary features in liver histology of children with autoimmune liver disease

OBJECTIVES AND STUDY

Various degrees of biliary changes are considered to be part of the histological picture of children with pediatrics autoimmune liver disease (AILD), but the literature is scarce and confusing. We aimed to describe the characteristics of children with AILD (autoimmune hepatitis, AIH, and autoimmune sclerosing cholangitis, ASC) focusing on the prevalence and type of biliary abnormalities on initial biopsy to see whether ASC was predictable on histological ground.

METHODS

The files of children diagnosed with AILD were reviewed. The Ishak score was used to grade inflammation and fibrosis on biopsy; a biliary score was built to grade bile duct injury. Demographic, laboratory and histological features at diagnosis were reported and compared between the two groups (AIH vs ASC).

RESULTS

Forty-one patients were diagnosed with AIH (n = 24), ASC (n = 13) and PSC (n = 4) between 2009 and 2018. Twenty-nine patients [F = 76%, AIH = 20, ASC = 9, median age at diagnosis 11.7 (range 2.2-17.8)] were included in the study; 12 (4 with PSC) were excluded. Prevalence of inflammatory bowel disease was higher in ASC group (56% vs 10% in AIH, p < 0.05). On histology 17% had cirrhosis. The grade of biliopathy with AILD was moderate in 72% and severe in 31%, and overall more prominent in ASC (p = 0.031). The inflammation of the bile ducts was classified as "multifocal" or "diffuse" mainly in ASC patients (89% vs 45% in AIH, p = 0.043). Periductular fibrosis was reported in 52% of AILD patients, with a higher mean score in ASC group (p < 0.05). However, ductular reaction, biliary metaplasia and granulomatous cholangitis were equally reported in AIH and ASC, providing no clear-cut for the distinction of the two entities in the global histological evaluation.

CONCLUSIONS

Majority of patients with pediatrics AILD have "moderate" or "severe" features of biliopathy; AIH and ASC are not easily distinguishable on histological ground at diagnosis, and therefore, the cholangiogram remains the only effective tool to differentiate patients with AIH from those with ASC. Further prospective studies are needed to better define histological biliary features in AILD, assess if the biliopathy responds to immunosuppressive treatment and evaluate its impact on long-term outcome.

Primary Biliary Cholangitis and Autoimmune Hepatitis

Primary biliary cholangitis and autoimmune hepatitis are common autoimmune diseases of the liver. Both have typical clinical presentations, including certain autoantibodies on serologic testing. Histologic features are also often typical: primary biliary cholangitis shows bile duct destruction (sometimes with granulomas), and autoimmune hepatitis shows prominent portal and lobular lymphoplasmacytic inflammation. Both have a wide differential diagnosis, including one another; they may also simultaneously occur within the same patient. Careful use of clinical and histologic criteria may be necessary for diagnosis. First-line therapy is immunosuppression for autoimmune hepatitis and ursodeoxycholic acid for primary biliary cholangitis. Both diseases may progress to cirrhosis.

Therapeutic effects of hepatocyte growth factor-overexpressing dental pulp stem cells on liver cirrhosis in a rat model

Cirrhosis is the terminal stage of hepatic diseases and is prone to develop into hepatocyte carcinoma. Increasing evidence suggests that the transplantation of dental pulp stem cells (DPSCs) may promote recovery from cirrhosis, but the key regulatory mechanisms involved remain to be determined. In this study, we overexpressed human hepatocyte growth factor (hHGF) in primary rat DPSCs and evaluated the effects of HGF overexpression on the biological behaviors and therapeutic efficacy of grafted DPSCs in cirrhosis. Liver cirrhosis was induced via the intraperitoneal injection of CCl₄ twice weekly for 12 weeks and was verified through histopathological and serological assays. HGF was overexpressed in DPSCs via transduction with a hHGF-lentiviral vector and confirmed based on the elevated expression and secretion of HGF. The HGF-overexpressing DPSCs were transplanted into rats intravenously. The HGF-overexpressing DPSCs showed increased survival and hepatogenic differentiation in host liver tissue at 6 weeks after grafting. They also exhibited a significantly greater repair potential in relation to cirrhosis pathology and impaired liver function than did DPSCs expressing HGF at physiological levels. Our study may provide an experimental basis for the development of novel methods for the treatment of liver cirrhosis in clinical practice.

Molecular signature of active fibrogenesis prevails in biliary atresia after successful portoenterostomy

BACKGROUND

In biliary atresia mechanisms of progressive liver injury leading to need of liver transplantation after successful portoenterostomy remain unknown. A better understanding is a prerequisite for development of novel therapies to extend native liver survival, and we aimed to unravel molecular characteristics of liver injury after successful portoenterostomy.

METHODS

Liver biopsies obtained from 28 biliary atresia children during successful portoenterostomy and at median age 3.0 years were studied. Biopsies were analyzed for histology and immunohistochemical expression of collagen 1, myofibroblast marker α-smooth muscle actin, and cytokeratin-7 positive ductal reactions. Hepatic ribonucleic acid (RNA) expression of growth factors and inflammatory cytokines was evaluated. Intestinal failure patients with comparable liver fibrosis and nonfibrotic gallstone patients and donor livers were controls.

RESULTS

After successful portoenterostomy, histologic cholestasis resolved and portal inflammation reduced, while fibrosis along with ductal reactions and overexpression of collagen and α-smooth muscle actin persisted. At follow-up, liver RNA expression of collagen and platelet-derived growth factor was increased, whereas RNA expression of various inflammatory cytokines remained low. Disappearance of periductal α-smooth muscle actin expression after successful portoenterostomy (36% of patients) associated with contracted ductal reactions and reduced progression of fibrosis, collagen accumulation, platelet-derived growth factor RNA expression, and serum levels of bile acids and bilirubin. Fibrosis progressed less rapidly in syndromic than in isolated biliary atresia patients.

CONCLUSION

These findings suggest that instead of inflammation, molecular signature of active fibrogenesis in association with ductal reactions prevails in long-term native liver survivors with biliary atresia. Patients should be stratified for isolated and syndromic disease forms in interventional studies.

Revaluation of vanishing bile duct syndrome

Vanishing bile duct syndrome (VBDS) can result from multiple etiologies, including congenital and genetic diseases, ischemic causes, neoplastic disorders, infections, immune disorders, drugs, idiopathic adulthood ductopenia (IAD) and so on. Recently, lymphoma, HIV/AIDS and drugs were identified to be major etiologies in the reported cases, some of which presented complex clinical course and were contributed by more than one etiological factor. Hepatic biopsy must be done for the diagnosis of VBDS and immunohistochemical staining for cytokeratin 7 (CK7) and CK19 has contributed to the establishment of diagnosis of VBDS. VBDS can be usually treated with symptomatic and supportive therapy, etiological therapy, liver transplantation, ursodeoxycholic acid and immunosuppressive agents. Glucocorticoids can be tried to switch to mycophemolate mofeil or tacrolimus when their effects are poor or side effects are severe. Severe cases ought to receive multimodality therapy besides plasmapheresis.

Silymarin-loaded Eudragit(®) RS100 nanoparticles improved the ability of silymarin to resolve hepatic fibrosis in bile duct ligated rats

Some nano-formulations of silymarin (SM), a drug commonly used for liver diseases, were developed to overcome its poor solubility and poor bioavailability; antifibrotic effect of these formulations has not been tested yet. In this study we aimed to formulate and evaluate silymarin-loaded Eudragit(®) RS100 nanoparticles (SMnps) and to test the capability of SMnps to reverse an established fibrosis model. SMnps were prepared by solvent evaporation and nano-precipitation techniques. The influence of drug:polymer ratio, concentration of surfactant in the aqueous phase on particle size, drug entrapment efficiency (EE) % and in vitro drug releases were investigated. For in vivo evaluation, bile duct ligated (BDL)-rats were treated with either SM or SMnps every other day (125mg/kg) orally for 3 weeks started 3 weeks after BDL. Liver function tests, oxidative stress and fibrosis/fibrogenesis process were evaluated using biochemical and histopathological techniques. The formulation No (F4) of SMnps showed an average particle size of 632.28±12.15nm, a drug EE% of 89.47±1.65% and released the drug in a prolonged manner over 24h. The prepared SMnps were nearly spherical with smooth surfaces. In BDL-rats, treatments with either SM or SMnps corrected liver function and oxidative stress. Only SMnps was able to reverse the induced fibrosis; SMnps significantly decreased serum tumor necrosis factor- α (TNF-α), serum transforming growth factor- β1 (TGF-β1), hepatic hydroxyproline and downregulated the hepatic expression of tissue inhibitor metalloproteinase-1 (TIMP-1) and cytokeratin-19 (CK-19), whilst increased hepatic hepatocytes growth factor (HGF) and upregulated the hepatic expression of matrix metalloproteinase-2 (MMP-2) and increased MMP-2/TIMP-1 ratio at mRNA level. Livers of rats treated with SMnps showed very little collagen in ECM and restored hepatic architecture as compared to either BDL rats or rats treated with SM.

CONCLUSION

Formulation of silymarin as nanoparticles improved its ability to resolve cholestasis-induced liver fibrosis by restoring hepatic regenerative capabilities. Therefore, formulation of SMnps may represent a step forward in the field of anti-fibrotic drug development.

Liver fibrosis during the development of biliary atresia: Proof of principle in the murine model

BACKGROUND

The murine model of biliary atresia (BA) is used for examining the pathogenesis of BA. The aim of the study was description of the morphological features and illustrating the detailed development of fibrosis using the Biliary Atresia Research Consortium (BARC) system.

METHODS

Neonatal mice were injected intraperitoneally with rhesus rotavirus (RRV) strain (N=17). Healthy mice were the control group (N=29). All mice were sacrificed at 7 or 14days after birth. Two pathologists examined the morphological features using the BARC system; CK19, αSMA and collagen type I were assessed by immunohistochemistry.

RESULTS

In RRV mice, portal fibrous expansion with focal bile duct proliferation and strong portal cellular infiltrate was found in contrast to healthy mice. In RRV mice, CK19 bile duct staining was significantly less or absent (p<0.01), with stronger portal staining of collagen type I (p=0.02). Expansion of staining for αSMA was more in RRV mice (p<0.01), but αSMA portal staining was stronger in healthy mice (p=0.02).

CONCLUSIONS

The morphological features observed in the murine model of BA correspond with the BA characteristics according to the BARC criteria. Fibrosis is an important feature of the model. Therefore, this murine model is useful for investigating the pathogenesis of BA.

Native liver histology after successful portoenterostomy in biliary atresia

BACKGROUND

Biliary atresia is the most common indication for childhood liver transplantation. The effects of successful portoenterostomy (PE) on native liver histology remain unclear.

AIMS

We assessed changes in native liver histology after a successful PE in relation to liver function and clinical outcomes.

METHODS

In total, 70 native liver biopsies of 44 biliary atresia patients were obtained at PE (n=30), 4.2 years after successful PE (n=23) and 1.1 years after failed PE (n=17), and reviewed for cholestasis, fibrosis, inflammation, and cytokeratin 7 (CK7) immunopositivity (chronic cholestasis). Ten transplant donor livers served as controls.

RESULTS

After a successful PE [serum bilirubin 11 (2 to 35) μmol/L at biopsy], histologic native liver cholestasis completely resolved in 83% of the patients and portal inflammation significantly decreased. Nevertheless, enhanced fibrosis [Metavir stage 2 (1-4) vs. 4 (1-4)], bile duct proliferation [grade 2 (1-2) vs. 1 (0-2)], and periportal CK7 immunostaining [grade 1 (0-2) vs. 1 (0-4)] persisted in 100%, 87%, and 61% of subjects, respectively. Metavir fibrosis stage corresponded cirrhosis (stage 4) in 52% of the patients, associated with the presence of portal hypertension, and correlated with serum-conjugated bilirubin (r=0.601, P=0.002), bile duct proliferation (r=0.657, P=0.001), and CK7 positivity (r=0.657, P=0.001). Aspartate transferase to platelet ratio index predicted native liver fibrosis and development of esophageal varices. The degree of fibrosis and portal inflammation at PE were unrelated to native liver survival.

CONCLUSIONS

Despite resolution of cholestasis and decreasing inflammation, bile duct proliferation, periportal CK7 immunostaining, and fibrosis persist after successful PE. Fibrosis is associated with biochemical cholestasis, bile duct proliferation, CK7 immunopositivity (chronic cholestasis), and development of portal hypertension.

Peritumoral ductular reaction: a poor postoperative prognostic factor for hepatocellular carcinoma

Background

The role of ductular reaction (DR) in hepatocellular carcinoma (HCC) remains to be elucidated.

Methods

In this study, we tried to uncover possible effect by correlating peritumoral DR in a necroinflammatory microenvironment with postoperative prognosis in HCC. The expression of peritumoral DR/CK19 by immunohistochemistry, necroinflammation and fibrosis were assessed from 106 patients receiving curative resection for HCC. Prognostic values for these and other clinicopathologic factors were evaluated.

Results

Peritumoral DR significantly correlated with necroinflammation (r = 0.563, p = 3.4E-10), fibrosis (r = 0.435, p = 3.1E-06), AFP level (p = 0.010), HBsAg (p = 4.9E-4), BCLC stage (p = 0.003), TNM stage (p = 0.002), multiple nodules (p = 0.004), absence of tumor capsule (p = 0.027), severe microscopic vascular invasion (p = 0.031) and early recurrence (p = 0.010). Increased DR was significantly associated with decreased RFS/OS (p = 4.8E-04 and p = 2.6E-05, respectively) in univariate analysis and were identified as an independent prognostic factor (HR = 2.380, 95% CI = 1.250-4.534, p = 0.008 for RFS; HR = 4.294, 95% CI = 2.255-8.177, p = 9.3E-6 for OS) in multivariate analysis.

Conclusions

These results suggested that peritumoral DR in a necroinflammatory microenvironment was a poor prognostic factor for HCC after resection.

Frequency of hepatocellular fibrillar inclusions in European flounder (Platichthys flesus) from the Douro River estuary, Portugal

Liver lesions in wild fish have been associated with xenobiotic exposure. Facing reports of pollution in the Douro River estuary (north of Portugal), we have been making field surveys using fishes and targeting histopathological biomarkers of exposure and effect. Herein, we intended to better characterize and report the rate of one poorly understood lesion-hepatocellular fibrillar inclusions (HFI)-found in European flounder (Platichthys flesus). With this report, we aimed to establish sound baseline data that could be viewed as a starting point for future biomonitoring, while offering the world's second only pool of field data on such a liver toxicopathic lesion, which could be compared with data available from the UK estuaries. Sampling was done in the Douro River estuary over 1 year. A total of 72 animals were fished with nets, in spring-summer (SS) and autumn-winter (AW) campaigns. Livers were processed for histopathology and both routine and special staining procedures (alcian blue, periodic acid Schiff (PAS), tetrazonium coupling reaction). Immunohistochemistry targeted AE1/AE3 (pan cytokeratins). The severity of the HFI extent was graded using a system with four levels, varying from 0 (absence of HFI) to 3 (high relative density of cells with HFI). Cells (isolated/groups) with HFI appeared in 35 % or more of the fish, in the total samples of each season, and over 40 % in more homogeneous sub-samples. There were no significant differences when comparing samples versus sub-samples or SS versus AW. When merging the data sets from the two seasons, the frequency of fish with HFI was ≈36 % for the total sample and ≈49 % for the sub-sample. The extreme group (biggest and smallest fish) revealed a HFI frequency of only 16 %, which differed significantly from the total and sub-sampled groups. Immunostaining and PAS were negative for the HFI, and alcian blue could, at times, faintly stain the inclusions. These were positive with the tetrazonium reaction. We showed the presence of HFI in European flounder from the Douro River estuary, proving that they are essentially protein in nature, that no seasonal changes existed in the HFI frequency, and that it was rarer in the smallest and biggest fish groups. Within the ranges of weight/size of our total sample, we estimate that the frequency of HFI in the local flounder is ≈35 %. That rate stands as a baseline value for future assessments, namely for biomonitoring purposes targeting correlations with the estuary pollution status.

Isolation of EpCAM(+)/CD133 (-) hepatic progenitor cells

Progenitor cell-derived hepatocytes are critical for hepatocyte replenishment. Therefore, we established a line of human hepatic progenitor (HNK1) cells and determined their biological characteristics for experimental and therapeutic applications. HNK1 cells, isolated from human noncirrhotic liver samples with septal fibrosis, showed high expression of the hepatic progenitor cell (HPC) markers EpCAM, CK7, CK19, alpha-fetoprotein (AFP), CD90 (Thy1), and EFNA1. Expression of CD133 was very low. Ductular reactions at the periphery of cirrhotic nodules were immunohistochemically positive for these HPC markers, including EFNA1. Sodium butyrate, a differentiation inducer, induced hepatocyte-like morphological changes in HNK1 cells. It resulted in down-regulation of the hepatic progenitor cell markers EpCAM, CK7, CK19, AFP, and EFNA1 and up-regulation of mature hepatocyte markers, including albumin, CK8, and CK18. Furthermore, sodium butyrate treatment and a serial passage of HNK1 cells resulted in enhanced albumin secretion, ureagenesis, and CYP enzyme activity, all of which are indicators of differentiation in hepatocytes. However, HNK1 cells at passage 50 did not exhibit anchorage-independent growth capability and caused no tumors in immunodeficient mice, suggesting that they had no spontaneous malignant transformation ability. From this evidence, HNK1 cells were found to be EpCAM(+)/CD133(-) hepatic progenitor cells without spontaneous malignant transformation ability. We therefore conclude that HNK1 cells could be useful for experimental and therapeutic applications.

Hepatic involvement in paediatric patients with paracoccidioidomycosis: a histological study

AIM

Paracoccidioidomycosis is a systemic mycosis that is endemic to certain countries in Latin America. This study aimed to describe the histological features of liver involvement in patients with paracoccidioidomycosis aged <16 years of age who were treated between 1980 and 2010, with a diagnosis that was confirmed by detection of the fungus by pathological examination.

METHODS AND RESULTS

Liver tissue was obtained from one necropsy and 12 biopsies. Throughout 2007, biopsies were taken from patients with persistent jaundice or portal hypertension, after which biopsies became indicated due to elevated aminotransferase and low albumin levels. Using haematoxylin and eosin (H&E), Masson's trichrome and immunohistochemical (CK7 and CK19) staining, we noted degenerative alterations in bile duct cells and inflammatory injury to the bile ducts in 10 biopsies. Using immunohistochemistry for CK7 and CK19, we observed ductal proliferation in all 12 samples.

CONCLUSIONS

Bile duct injuries by inflammatory cells might explain the predominant increase in canalicular enzymes; immunohistochemistry is more sensitive in demonstrating ductular reactions and might show changes that are not apparent on H&E staining.

Isolation and characterization of biliary epithelial and stromal cells from resected human cholangiocarcinoma: a novel in vitro model to study tumor-stroma interactions

Cholangiocarcinoma (CCA) is a devastating malignancy arising from the bile ducts. Cancer-associated fibroblasts (CAFs) are key players in CCA invasiveness and in the generation of a desmoplastic reaction. The aim of the present study was to develop a novel model by which to study tumor-stroma interactions using primary cultures of human biliary epithelial cells (hBECs) and stromal cells (SCs) in CCA. hBECs and SCs, isolated from surgical resections (n=10), were semi-purified by centrifugation on a Percoll gradient; hBECs were further immunopurified. hBECs and SCs were characterized using epithelial [cytokeratin 7 (CK7) and CK19] and mesenchymal [vimentin (VMN), α-smooth muscle actin (α-SMA), CD68] cell markers. The purity of cultured cells was assessed by fluorescent immunocytochemistry. hBECs were HEA125/CK7/CK19-positive and VMN/α-SMA-negative. SCs were VMN/α-SMA-positive and CK7/CK19-negative. CCA 2-D culture models have been described but they use long-standing CCA cell lines of various biliary tumor cell origins with stromal cells derived from non-cholangiocarcinoma tissues. Recently, a novel 3-D organotypic co-culture model of rat cholangiocarcinoma was described. In the present study, we obtained pure and stable primary cultures of hBECs and SCs from CCA surgical specimens. These cell cultures may provide a useful tool by which to study CCA tumor-stroma interactions.

Portal, but not lobular, macrophages express matrix metalloproteinase-9: association with the ductular reaction and fibrosis in chronic hepatitis C

BACKGROUND

Liver macrophages are a heterogeneous cell population that produces factors involved in fibrogenesis and matrix turnover, including matrix metalloproteinase (MMP) -9. During liver injury, their close proximity to hepatic progenitor cells and the ductular reaction may enable them to regulate liver repair and fibrosis.

AIMS

To enumerate and characterise liver macrophages in patients with chronic hepatitis C, to determine whether a distinct population of macrophages is associated with the ductular reaction and portal fibrosis.

METHODS

Immunostaining for macrophage markers (CD68, CD163, CCR2), the ductular reaction (keratin-7) and MMP-9 was performed in liver biopsy sections from patients with chronic hepatitis C virus (HCV) (n = 85).

RESULTS

Portal tracts were more densely populated with macrophages (10.5 ± 0.36 macrophages/HPF) than lobules (7.2 ± 0.16 macrophages/HPF, P < 0.001) and macrophages were found in close proximity to the ductular reaction. ≥30% of portal and periductal macrophages expressed MMP-9 and these were significantly associated with increasing stage of fibrosis (rs  = 0.58, 0.68, respectively, both P < 0.001). In contrast, MMP-9(+) macrophages were largely absent in lobular regions and non-diseased liver. Hepatic MMP-9 mRNA levels and gelatinolytic activity were significantly associated with stage of fibrosis (rs  = 0.47, rs  = 0.89, respectively, both P < 0.001). Furthermore, a second distinct CCR2(+) macrophage population was localised to the centrilobular regions and was predominantly absent from portal and periductal areas.

CONCLUSIONS

These findings demonstrate significant regional differences in macrophage phenotypes, suggesting that there are at least two populations of liver macrophages. We propose that these populations have distinct contributions to the pathogenesis of chronic HCV-related liver disease.

Low-dose steroids associated with milder histological changes after pediatric liver transplantation

Controversy remains about the role of protocol liver biopsy for symptom-free recipients and about the long-term use of low-dose steroids after pediatric liver transplantation (LT). We conducted a national cross-sectional study of pediatric recipients who underwent LT between 1987 and 2007. Liver biopsy samples were taken from 54 patients (82% of survivors) after a median posttransplant follow-up of 11 years, and they were reviewed by 2 pathologists blinded to the clinical data. Biopsy samples from 18 patients (33%) showed nearly normal histology with no inflammation, fibrosis, or steatosis. Portal inflammation was detected in 14 samples (26%), showed no correlation with anti-nuclear antibodies, and was less frequent in the 35 patients whose immunosuppression included steroids (14% versus 47% of patients not using steroids, P = 0.008). Fibrosis was present in 21 biopsy samples (39%). According to the Metavir classification, 16 were stage 1, 3 were stage 2, and 2 were stage 3. The fibrosis stage correlated negatively with serum prealbumin levels (r = -0.364, P = 0.007) and positively with chronic cholestasis (cytokeratin 7 staining; r = 0.529, P < 0.001) and portal inflammation (r = 0.350, P = 0.01). Microvesicular steatosis was found in 23 biopsy samples (43% of patients in 5%-80% of hepatocytes), and it correlated with the body mass index (r = 0.458, P < 0.001) but not with steroid use. The age of the allograft (donor age plus follow-up time) correlated with higher serum gamma-glutamyltransferase (r = 0.472, P < 0.001) and conjugated bilirubin levels (r = 0.420, P = 0.002) as well as chronic cholestasis (r = 0.299, P = 0.03). The biopsy findings led to treatment changes in 10 patients (19%), whereas only 1 complication (subcapsular hematoma) was encountered. In conclusion, continuing low-dose steroids indefinitely after pediatric LT may have a positive effect on the long-term histological state of the liver graft. Allograft aging may lead to chronic cholestasis and thus contribute to the development of liver fibrosis.

Liver progenitor cell markers correlate with liver damage and predict short-term mortality in patients with alcoholic hepatitis

Alcoholic hepatitis (AH) is a severe condition developed in patients with underlying alcoholic liver disease. Ductular reaction has been associated with chronic alcohol consumption but there is no information regarding the extent of liver progenitor cell (LPC) proliferation in AH. The aim of this study was to investigate LPC markers in AH and its correlation with disease severity. Fifty-nine patients with clinical and histological diagnosis of AH were included in the study. LPC markers were assessed by real-time polymerase chain reaction (PCR) and immunohistochemistry. Standard logistic regression analysis and classification and regression trees (CART) analysis were used for statistical analysis. A microarray analysis showed an up-regulation of LPC markers in patients with AH. Real-time PCR demonstrated that epithelial cell adhesion molecule (EpCAM), Prominin-1, and Keratin7 were significantly increased in patients with AH compared with normal livers (P ≤ 0.01), chronic hepatitis C (P ≤ 0.01), and HCV-induced cirrhosis (P ≤ 0.01). Immunohistochemistry scores generated for Keratin7 and EpCAM demonstrated a good correlation with gene expression. Keratin7 gene expression correlated with liver failure as assessed by model for endstage liver disease score (r = 0.41, P = 0.006) and Maddrey's discriminant function (r = 0.43, P = 0.004). Moreover, Keratin7 (OR1.14, P = 0.004) and Prominin-1 (OR1.14, P = 0.002), but not EpCAM (OR1.16, P = 0.06), were identified as independent predictors of 90-day mortality. CART analysis generated an algorithm based on the combination of Keratin7 and EpCAM gene expression that stratified three groups of patients with high, intermediate, and low short-term mortality (89%, 33%, and 6%, respectively; area under the receiver operating curve 0.73, 95% confidence interval 0.60-0.87). Keratin7 expression provided additional discrimination potential to the age, bilirubin, international normalization ratio, creatinine (ABIC) score.

CONCLUSION

LPC markers correlate positively with severity of liver disease and short-term mortality in AH patients. This study suggests that LPC proliferation may be an important feature of AH pathophysiology.

Cytokeratins in hepatitis

Experimental and clinical evidence suggests that cytokeratins (CK), among other physiological functions, are expressed in hepatocytes and can be released in the bloodstream after acute or chronic inflammatory liver injury. Interest in CK in viral and nonviral hepatitis has been rapidly increasing during the last years, especially as they have been proposed as circulating biomarkers of hepatocyte necrosis and apoptosis. In the present review, we sought to summarize and discuss the alterations in circulating CK levels in different form viral and nonviral hepatitis, as well as their potential relation with liver histology. Understanding the mechanisms of hepatitis impact on CK and vice versa is a promising area of research that will positively enhance our understanding of the complexity of acute and chronic inflammatory liver injury.