ETS Proto-oncogene 1 Transcriptionally Up-regulates the Cholangiocyte Senescence-associated Protein Cyclin-dependent Kinase Inhibitor 2A

Primary sclerosing cholangitis (PSC) is a chronic, fibroinflammatory cholangiopathy (disease of the bile ducts) of unknown pathogenesis. We reported that cholangiocyte senescence features prominently in PSC and that neuroblastoma RAS viral oncogene homolog (NRAS) is activated in PSC cholangiocytes. Additionally, persistent microbial insult (e.g. LPSs) induces cyclin-dependent kinase inhibitor 2A (CDKN2A/p16INK4a) expression and senescence in cultured cholangiocytes in an NRAS-dependent manner. However, the molecular mechanisms involved in LPS-induced cholangiocyte senescence and NRAS-dependent regulation of CDKN2A remain unclear. Using our in vitro senescence model, we found that LPS-induced CDKN2A expression coincided with a 4.5-fold increase in ETS1 (ETS proto-oncogene 1) mRNA, suggesting that ETS1 is involved in regulating CDKN2A This idea was confirmed by RNAi-mediated suppression or genetic deletion of ETS1, which blocked CDKN2A expression and reduced cholangiocyte senescence. Furthermore, site-directed mutagenesis of a predicted ETS-binding site within the CDKN2A promoter abolished luciferase reporter activity. Pharmacological inhibition of RAS/MAPK reduced ETS1 and CDKN2A protein expression and CDKN2A promoter-driven luciferase activity by ∼50%. In contrast, constitutively active NRAS expression induced ETS1 and CDKN2A protein expression, whereas ETS1 RNAi blocked this increase. Chromatin immunoprecipitation-PCR detected increased ETS1 and histone 3 lysine 4 trimethylation (H3K4Me3) at the CDKN2A promoter following LPS-induced senescence. Additionally, phospho-ETS1 expression was increased in cholangiocytes of human PSC livers and in the Abcb4 (Mdr2)-/- mouse model of PSC. These data pinpoint ETS1 and H3K4Me3 as key transcriptional regulators in NRAS-induced expression of CDKN2A, and this regulatory axis may therefore represent a potential therapeutic target for PSC treatment.

Eosinophilic cholangitis is a potentially underdiagnosed etiology in indeterminate biliary stricture

AIM

To investigate presence and extent of eosinophilic cholangitis (EC) as well as IgG4-related disease in patients with indeterminate biliary stricture (IBS).

METHODS

All patients with diagnosis of sclerosing cholangitis (SC) and histopathological samples such as biopsies or surgical specimens at University Hospital Frankfurt from 2005-2015 were included. Histopathological diagnoses as well as further clinical course were reviewed. Tissue samples of patients without definite diagnosis after complete diagnostic work-up were reviewed regarding presence of eosinophilic infiltration and IgG4 positive plasma cells. Eosinophilic infiltration was as well assessed in a control group of liver transplant donors and patients with primary sclerosing cholangitis.

RESULTS

one hundred and thirty-five patients with SC were included. In 10/135 (13.5%) patients, no potential cause of IBS could be identified after complete diagnostic work-up and further clinical course. After histopathological review, a post-hoc diagnosis of EC was established in three patients resulting in a prevalence of 2.2% (3/135) of all patients with SC as well as 30% (3/10) of patients, where no cause of IBS was identified. 2/3 patients with post-hoc diagnosis of EC underwent surgical resection with suspicion for malignancy. Diagnosis of IgG4-related cholangitis was observed in 7/135 patients (5.1%), whereas 3 cases were discovered in post-hoc analysis. 6/7 cases with IgG4-related cholangitis (85.7%) presented with eosinophilic infiltration in addition to IgG4 positive plasma cells. There was no patient with eosinophilic infiltration in the control group of liver transplant donors (n = 27) and patients with primary sclerosing cholangitis (n = 14).

CONCLUSION

EC is an underdiagnosed benign etiology of SC and IBS, which has to be considered in differential diagnosis of IBS.

Decreased Expression of Vitamin D Receptor Affects an Immune Response in Primary Biliary Cholangitis via the VDR-miRNA155-SOCS1 Pathway

Primary biliary cholangitis (PBC) is an immune-mediated cholestatic disease. Vitamin D receptor (VDR)-dependent signaling constrains an inflammatory response by targeting the miRNA155-SOCS1 (suppressor of cytokine signaling 1) axis. The VDR-miRNA155-SOCS1 pathway was investigated in the context of the autoimmune response associated with PBC. Human liver tissues from non-cirrhotic PBC (n = 22), cirrhotic PBC (n = 22), cirrhotic primary sclerosing cholangitis (PSC, n = 13), controls (n = 23), and peripheral blood mononuclear cells (PBMC) obtained from PBC (n = 16) and PSC (n = 10) patients and healthy subjects (n = 11) were used for molecular analyses. VDR mRNA and protein expressions were substantially reduced in PBC livers (51% and 59%, respectively). Correspondingly, the decrease of SOCS1 protein expression in PBC livers, after normalization to a marker of lymphocytes and forkhead family transcriptional regulator box P3 (FOXP3, marker of Treg), was observed, and this phenomenon was accompanied by enhanced miRNA155 expression. In PSC livers, protein expressions of VDR and SOCS1 were comparable to the controls. However, in PBM cells, protein expressions of VDR and SOCS1 were considerably decreased in both PBC and PSC. We demonstrated that VDR/miRNA155-modulated SOCS1 expression is decreased in PBC which may lead to insufficient negative regulation of cytokine signaling. These findings suggest that the decreased VDR signaling in PBC could be of importance in the pathogenesis of PBC.

Two Cases of Primary Sclerosing Cholangitis Overlapping with Autoimmune Hepatitis in Adults

Overlap syndrome between primary sclerosing cholangitis (PSC) and autoimmune hepatitis (AIH) is extremely rare in Japan. We herein report two adult patients with PSC-AIH overlap syndrome. They were diagnosed with PSC-AIH overlap syndrome based on the findings of endoscopic retrograde cholangiography and liver biopsy, and using the International Autoimmune Hepatitis Group scoring system. In both cases, PSC preceded AIH, and combination therapy with steroid and ursodeoxycholic acid was effective. Because there are few reported cases in Japan, it is important to study more cases to shed light on the clinical and pathological features of PSC-AIH overlap syndrome.

Autoimmune hepatitis with sclerosing cholangitis in a patient with thiopurine methyltransferase deficiency: case presentation

The association between two autoimmune diseases is known in the literature as overlap syndrome. We present the case of an 18-year-old boy, diagnosed at the age of 13 with an overlap syndrome between type I autoimmune hepatitis and sclerosing cholangitis. The response to immunosuppressant therapy was hampered by azathioprine-induced toxicity causing severe pancytopenia, as a result of thiopurine methyltransferase enzyme genetic deficiency. Treatment was replaced by mycophenolate mofetil. Although the relapse rate was reduced, the disease progressed to cirrhosis. Specific features of this case were the overlap syndrome, young age of onset, especially for sclerosing cholangitis, azathioprine toxicity that influenced the prognosis and the treatment problems regarding the use and efficiency of alternative immunosuppressant agents in pediatric patients.

Early Peribiliary Hyperenhancement on MRI in Patients with Primary Sclerosing Cholangitis: Significance and Association with the Mayo Risk Score

The aims of this study are to assess any relationship between peribiliary hyperenhancement on MRI in patients with primary sclerosing cholangitis (PSC) and their Mayo risk score and to assess which timing of peribiliary hyperenhancement correlates best with the Mayo risk score. In this HIPAA-compliant, IRB-approved retrospective study, 101 patients who underwent MRI for known or suspected PSC were identified. Of those, 62 patients (mean age 48 years; 40 males) were diagnosed with PSC by a hepatologist based on findings on MRI, ERCP, and/or liver biopsy, and comprise the final cohort. Data were recorded on whether peribiliary hyperenhancement was present, the post-contrast phase and the extent of involvement. The components to calculate the Mayo risk score were recorded. Statistical analysis was performed using the student T test, Fisher's exact test, and the Kaplan-Meier estimate. Of 62 patients, 41 (66.1%) patients had a low-Mayo risk score (<0), 14 (22.6%) had an intermediate-risk score (≤2 and >0), and 7 (11.3%) had a high-risk score (>2). On MRI, 29 (46.8%) patients demonstrated arterial peribiliary hyperenhancement. Both the presence and extent of peribiliary hyperenhancement showed significant associations with Mayo risk score (p < 0.01). Using the combined end point of liver transplantation or death, there was a statistically significant difference in survival times between those with and those without arterial peribiliary hyperenhancement (p < 0.05). The presence of arterial peribiliary hyperenhancement in patients with PSC on MRI is associated with higher Mayo risk scores and may suggest a poorer prognosis.

The importance of IgG4 screening in patients diagnosed with primary sclerosing cholangitis in the past: A case rediagnosed as IgG4-SC after 10 years

RATIONALE

While primary sclerosing cholangitis (PSC) has been recognized for decades, immunoglobulin G4-related sclerosing cholangitis (IgG4-SC) has been correctly diagnosed only in recent years. PSC and IgG4-SC show similar clinical symptoms, serologic markers, and imaging results, but the treatment strategies and prognosis of patients differ.

PATIENT CONCERNS

Here, we present the case report of a patient diagnosed with PSC for 10 years and rediagnosed with IgG4-SC recently, to emphasize the importance of screening serum IgG4 levels in patients with previous diagnosis of PSC.

DIAGNOSES

A 57-year-old woman with 10-year history of PSC was hospitalized due to pruritus. In 2004, the patient underwent cholecystectomy and cholangioenterostomy because of unexplained jaundice with pancreatic swelling. In the last 10 years, her liver enzyme levels were continuously elevated. The latest liver function profile showed elevated alanine aminotransferase, aspartate aminotransferase, and total bilirubin. IgG4 was 3.69 (0.03-2.01 g/L). Immunohistochemical staining of the surgical specimen showed >10 IgG4-positive plasma cells per high-power field, and IgG4+/IgG+ plasma cells >40%.

INTERVENTIONS AND OUTCOMES

She was treated with prednisone 40 mg once-daily and the dose was gradually tapered. The patient remains well after 18 months.

LESSONS SUBSECTIONS

Patients with IgG4-SC may be misdiagnosed as PSC due to lack of IgG4 screening. It is important to perform IgG4 screening in patients diagnosed as PSC. Steroid is effective to prevent disease progression in these patients.

[A Case of Primary Sclerosing Cholangitis Difficult to Distinguish from a Hilar Cholangiocarcinoma]

A 78-year-old man, who had presented with onset of ulcerative colitis at the age of 56 years and had been in remission for the past several years, attended our hospital with a diagnosis of obstructive jaundice. A hilar cholangiocarcinoma with right hepatic artery invasion was suspected on contrast enhanced CT. An endoscopic retrograde cholangiography indicated Bismuth type 2 stenosis. The stenotic bile duct brushings revealed no malignancy. Primary sclerosing cholangitis(PSC)and IgG4- related cholangitis were included in the differential diagnosis; however, a significant result could not be obtained in any other examinations. A hilar cholangiocarcinoma could not be ruled out, and rt. hepatic lobectomy and caudate lobectomy with resection of the extrahepatic bile duct were performed after obtaining informed consent. The histopathological findings revealed no atypical cells in the stenotic lesion, but fibrosis and inflammatory cell infiltration were observed around the bile duct. These findings were consistent with PSC. On the other hand, atypical cell proliferation with lymph duct infiltration was found in the mucosa of the gall bladder. It is difficult to preoperatively diagnose PSC localized to the hilar bile duct, and if possible, the existence of concomitant malignant lesions in the biliary tract should be considered.

Inhibition of mast cell-secreted histamine decreases biliary proliferation and fibrosis in primary sclerosing cholangitis Mdr2(-/-) mice

Hepatic fibrosis is marked by activation of hepatic stellate cells (HSCs). Cholestatic injury precedes liver fibrosis, and cholangiocytes interact with HSCs promoting fibrosis. Mast cells (MCs) infiltrate following liver injury and release histamine, increasing biliary proliferation. We evaluated if inhibition of MC-derived histamine decreases biliary proliferation and fibrosis. Wild-type and multidrug resistance 2 knockout mice (9-11 weeks) were treated with cromolyn sodium for 1 week to block MC-derived histamine. Biliary mass and proliferation were evaluated by immunohistochemistry for cytokeratin 19 and Ki-67. Bile flow, bicarbonate excretion, and total bile acids were measured in all mice. Fibrosis was evaluated by sirius red/fast green staining and by quantitative polymerase chain reaction for alpha-smooth muscle actin, fibronectin, collagen type 1a, and transforming growth factor-beta 1. HSC activation was evaluated by quantitative polymerase chain reaction in total liver and immunofluorescent staining in tissues for synaptophysin 9. Histamine serum secretion was measured by enzymatic immunoassay. Mouse liver and human liver samples from control or primary sclerosing cholangitis patients were evaluated for MC markers by quantitative polymerase chain reaction and immunohistochemistry. In vitro, cultured MCs were transfected with histidine decarboxylase short hairpin RNA to decrease histamine secretion and subsequently cocultured with cholangiocytes or HSCs prior to measuring fibrosis markers, proliferation, and transforming growth factor-beta 1 secretion. Treatment with cromolyn sodium decreased biliary proliferation, fibrosis, histamine secretion, and bile flow in multidrug resistance 2 knockout mice. Primary sclerosing cholangitis mice and patients have increased MCs. Knockdown of MC histidine decarboxylase decreased cholangiocyte and HSC proliferation/activation.

CONCLUSION

MCs are recruited to proliferating cholangiocytes and promote fibrosis. Inhibition of MC-derived histamine decreases fibrosis, and regulation of MC mediators may be therapeutic for primary sclerosing cholangitis. (Hepatology 2016;64:1202-1216).

BCL3 Reduces the Sterile Inflammatory Response in Pancreatic and Biliary Tissues

BACKGROUND & AIMS

Under conditions of inflammation in the absence of micro-organisms (sterile inflammation), necrotic cells release damage-associated molecular patterns that bind to Toll-like receptors on immune cells to activate a signaling pathway that involves activation of IκB kinase and nuclear factor κB (NF-κB). Little is known about the mechanisms that control NF-κB activity during sterile inflammation. We analyzed the contribution of B-cell CLL/lymphoma 3 (BCL3), a transcription factor that associates with NF-κB, in control of sterile inflammation in the pancreas and biliary system of mice.

METHODS

Acute pancreatitis (AP) was induced in C57BL/6 (control) and Bcl3(-/-) mice by intraperitoneal injection of cerulein or pancreatic infusion of sodium taurocholate. We also studied Mdr2(-/-) mice, which develop spontaneous biliary inflammation, as well as Bcl3(-/-)Mdr2(-/-) mice. We performed immunohistochemical analyses of inflamed and noninflamed regions of pancreatic tissue from patients with AP or primary sclerosing cholangitis (PSC), as well as from mice. Immune cells were characterized by fluorescence-activated cell sorting analysis. Control or Bcl3(-/-) mice were irradiated, injected with bone marrow from Bcl3(-/-) or control mice, and AP was induced.

RESULTS

Pancreatic or biliary tissues from patients with AP or PSC had higher levels of BCL3 and phosphorylated RelA and IκBα in inflamed vs noninflamed regions. Levels of BCL3 were higher in pancreata from control mice given cerulein than from mice without AP, and were higher in biliary tissues from Mdr2(-/-) mice than from control mice. Bcl3(-/-) mice developed more severe AP after administration of cerulein or sodium taurocholate than control mice; pancreata from the Bcl3(-/-) mice with AP had greater numbers of macrophages, myeloid-derived suppressor cells, dendritic cells, and granulocytes than control mice with AP. Activation of NF-κB was significantly prolonged in Bcl3(-/-) mice with AP, compared with control mice with AP. Bcl3(-/-)Mdr2(-/-) mice developed more severe cholestasis and had increased markers of liver injury and increased proliferation of biliary epithelial cells and hepatocytes than Mdr2(-/-) mice. In experiments with bone marrow chimeras, expression of BCL3 by acinar cells, but not myeloid cells, was required for reduction of inflammation during development of AP. BCL3 inhibited ubiquitination and proteasome-mediated degradation of p50 homodimers, which prolonged binding of NF-κB heterodimers to DNA.

CONCLUSIONS

BCL3 is up-regulated in inflamed pancreatic or biliary tissues from mice and patients with AP or cholangitis. Its production appears to reduce the inflammatory response in these tissues via blocking ubiquitination and proteasome-mediated degradation of p50 homodimers.

[CLINICAL AND MORPHOLOGICAL CHARACTERISTICS OF INTESTINAL LESIONS IN PATIENTS WITH PRIMARY SCLEROSING CHOLANGITIS]

OBJECTIVE

To compare the clinical, endoscopic picture and morphological changes of the intestinal mucosa in patients with primary sclerosing cholangitis (PSC).

MATERIALS AND METHODS

31 patients with PSC (women - 15 men - 16) were included in study group. The diagnosis of ulcerative colitis (UC) was established in 8 patients, Crohn’s disease (CD) - in 5, unclassified colitis (UCC) - in 7, and 11 patients had no clinical and endoscopic signs of IBD. The control group consisted of 30 patients with IBD: UC - 20 patients, CD - 10 persons. All the patients performed ileocolonoscopy (ICS) with multiple biopsy and histological examination of material.

RESULTS

The prevalence of IBD in patients with PSC was 64.5%. IBD with PSC was characterized by extensive colitis with mild clinical activity. Morphological activity of IBD associated with PSC was usually moderate and severe. Morphological activity of disease in IBD/PSC group was lower than in UC alone (p < 0.05). IBD onset came before PSC symptoms (p < 0.05). Distal gradient of inflammation in colon predominated in IBD/PSC group when disease starts with IBD symptoms, in case of PSC symptoms - proximal gradient was more frequent. In IBD/PSC group affected ileum were detected in a third of cases, including CD ileitis - 60%, backwash ileitis in UC (NCC) in 26.7%, that was significantly frequently than in UC alone (p = 0.02). Within the IBD/PSC group 30% of patients with colitis were without damaging of rectum. In all the patients with PSC without clinical, endoscopic signs of colitis polymorphocellular infiltration of mucosa were founded. Eosinophilic infiltration of mucosa in group of PSC met significantly more frequently than in other study groups. Fibrosis of intestinal mucosa was founded significantly more frequently in group of PSC without IBD compared with UC/PSC and UC patients, but not with CD group.

CONCLUSIONS

For IBD in PSC extensive colitis without lesions of the rectum, backwash ileitis are common. There are some morphological differences in the intestinal lesions within the IBD/PSC patients depending on the type of disease onset. There is a dissociation between low clinical activity and intensive morphological inflammation. When PSC had no clinical features of IBD, a microscopic ileocolitis (characterized by eosinophilic infiltration and fibrosis of the intestinal mucosa) without nosological classification was founded in all patients.

Inflammation But Not Biliary Obstruction Is Associated With Carbohydrate Antigen 19-9 Levels in Patients With Primary Sclerosing Cholangitis

BACKGROUND & AIMS

Assays that measure the serum level of carbohydrate antigen 19-9 (CA19-9) are used to screen patients with primary sclerosing cholangitis (PSC) for malignancies. However, in patients with PSC, cholestasis, and bacterial cholangitis, the CA19-9 level can be affected by variants in the fucosyltransferases 2 and 3 genes (FUT2 and FUT3), which regulate the production of CA19-9. We investigated how these genotypes affect cancer screening in these patients.

METHODS

We performed a retrospective analysis of data from 209 patients with PSC (19 patients with biliary malignancy, 23 patients with cholestasis and bacterial cholangitis) treated at the University Hospital Heidelberg from 1987 through 2014. We collected data on the maximum serum level of CA19-9; laboratory measures of cholestasis or inflammation; the presence of dominant stenosis, cholestasis, and bacterial cholangitis; and FUT2 and FUT3 genotypes. Patients were assigned to intermediate (n = 161) or high (n = 48) CA19-9 biosynthesis groups, based on FUT2 and FUT3 genotypes. Patients incapable of CA19-9 biosynthesis, based on genetic features, were excluded.

RESULTS

The median level of CA19-9 was 31.1 U/mL in cancer-free patients. The CA19-9 level correlated with the level of C-reactive protein (P < .001); high CA19-9 biosynthesis correlated with high leukocyte counts (P = .037), but not intermediate CA19-9 biosynthesis. There was no correlation between the level of CA19-9 and laboratory markers of cholestasis. The level of CA19-9 was the lowest in patients without biliary obstruction, cholestasis, or bacterial cholangitis (7.8 U/mL), followed by patients with only obstruction (28.0 U/mL), and then patients with cholestasis and bacterial cholangitis (77.0 U/mL and 205.4 U/mL in patients without or with concomitant obstruction, respectively). The greatest increase in CA19-9 as a result of cholestasis and bacterial cholangitis was observed in patients in the high CA19-9 biosynthesis group.

CONCLUSIONS

In patients with PSC, cholestasis has little effect on the level of CA19-9, but cholestasis and bacterial cholangitis increase the level. Their effects on CA19-9 level depend on the FUT2 and FUT3 genotype. These findings support the analysis of FUT2 and FUT3 genotype during follow-up evaluation of patients with PSC.

Low Serum Hepcidin in Patients with Autoimmune Liver Diseases

Hepcidin, a liver hormone, is important for both innate immunity and iron metabolism regulation. As dysfunction of the hepcidin pathway may contribute to liver pathology, we analysed liver hepcidin mRNA and serum hepcidin in patients with chronic liver diseases. Hepcidin mRNA levels were determined in liver biopsies obtained from 126 patients with HCV (n = 21), HBV (n = 23), autoimmune cholestatic disease (primary biliary cirrhosis and primary sclerosing cholangitis; PBC/PSC; n = 34), autoimmune hepatitis (AIH; n = 16) and non-alcoholic fatty liver disease (NAFLD; n = 32). Sera sampled on the biopsy day from the same patients were investigated for serum hepcidin levels. Hepatic hepcidin mRNA levels correlated positively with ferritin and negatively with serum γ-GT levels. However, no correlation was found between serum hepcidin and either ferritin or liver hepcidin mRNA. Both serum hepcidin and the serum hepcidin/ferritin ratio were significantly lower in AIH and PBC/PSC patients’ sera compared to HBV, HCV or NAFLD (P<0.001 for each comparison) and correlated negatively with serum ALP levels. PBC/PSC and AIH patients maintained low serum hepcidin during the course of their two-year long treatment. In summary, parallel determination of liver hepcidin mRNA and serum hepcidin in patients with chronic liver diseases shows that circulating hepcidin and its respective ratio to ferritin are significantly diminished in patients with autoimmune liver diseases. These novel findings, once confirmed by follow-up studies involving bigger size and better-matched disease subgroups, should be taken into consideration during diagnosis and treatment of autoimmune liver diseases.

Functional gadoxetate disodium-enhanced MRI in patients with primary sclerosing cholangitis (PSC)

OBJECTIVES

To assess the value of variable flip angle-based T1 liver mapping on gadoxetate disodium-enhanced MRI in patients with primary sclerosing cholangitis (PSC) for evaluation of global and segmental liver function, and determine a possible correlation with disease severity.

METHODS

Sixty-one patients (19 female, 42 male; mean age 41 years) with PSC were included in this prospective study. T1 mapping was performed using a 3D-spoiled GRE sequence (flip angles 5°, 15°, 20°, 30°) before, 16 (HP1) and 132 min (HP2) after contrast injection. T1 values were measured and compared (Wilcoxon-Test) by placing ROIs in each liver segment. The mean reduction of T1 relaxation time at HP1 and HP2 was calculated and correlated with liver function tests (LFTs), MELD, Mayo Risk and Amsterdam Scores (Spearman correlation).

RESULTS

Significant changes of T1 relaxation times between non-enhanced and gadoxetate disodium-enhanced MRI at HP1 and HP2 could be observed in all liver segments (p < 0.0001). A significant correlation of T1 reduction could be observed with LFTs, MELD and Mayo Risk Score (p < 0.05).

CONCLUSIONS

T1 mapping of the liver using a variable flip angle-based sequence is a feasible technique to evaluate liver function on a global level, and may be extrapolated on a segmental level in patients with PSC.

KEY POINTS

• T1 mapping enables evaluation of global liver function in PSC. • T1 relaxation time reduction correlates with the MELD and MayoRisk Score. • Extrapolated, T1 mapping may allow for segmental evaluation of liver function.

A new Mdr2(-/-) mouse model of sclerosing cholangitis with rapid fibrosis progression, early-onset portal hypertension, and liver cancer

We previously characterized the Mdr2(Abcb4)(-/-) mouse as a reproducible model of chronic biliary liver disease. However, it demonstrates relatively slow fibrosis progression, possibly due to its fibrosis-resistant genetic background. We aimed to improve the model by moving it onto a fibrosis-susceptible background. We generated novel BALB/c.Mdr2(-/-) mouse via genetic backcross onto highly fibrosis-susceptible BALB/c substrain, identified in inbred mouse strain screening. Liver fibrosis, portal pressure, and hepatic tumor burden in BALB/c.Mdr2(-/-) mice were studied up to 1 year of age in direct comparison to parental strain FVB.Mdr2(-/-). BALB/c.Mdr2(-/-) mice developed periductular onion-skin type fibrotic lesions and pronounced ductular reaction starting from 4 weeks of age. Compared to parental strain, BALB/c.Mdr2(-/-) mice demonstrated dramatically accelerated liver fibrosis, with threefold increase in collagen deposition and bridging fibrosis/early signs of cirrhosis at 12 weeks. This was accompanied by early-onset severe portal hypertension and twofold to fourfold increase in profibrogenic transcripts Col1a1 [procollagen α1(I)], Tgfb1, and Timp1. Primary liver cancers in BALB/c.Mdr2(-/-) developed earlier, with greater tumor burden compared to FVB.Mdr2(-/-). BALB/c.Mdr2(-/-) mice have unprecedented degree and rapidity of hepatic fibrosis progression and clinically relevant cirrhosis complications, such as early-onset portal hypertension and primary liver cancers. This new model will facilitate development of antifibrotic drugs and studies into mechanisms of biliary fibrosis progression.

Biliary multifocal chromosomal polysomy and cholangiocarcinoma in primary sclerosing cholangitis

OBJECTIVES

Polysomy detected by fluorescence in situ hybridization (FISH) is associated with cholangiocarcinoma (CCA) in patients with primary sclerosing cholangitis (PSC). However, a subset of PSC patients with polysomy do not manifest CCA even after long-term follow-up. It is unknown if patients with chromosomal gains detected by FISH in multiple areas of the biliary tree (i.e., multifocal polysomy, MFP) are more likely to be diagnosed with CCA than patients with unifocal polysomy (UFP). Therefore, our aim is to determine whether patients with MFP are more likely to manifest CCA compared with patients with other chromosomal abnormalities including UFP and other FISH subtypes.

METHODS

We performed a retrospective review of PSC patients without a mass lesion who underwent FISH testing at our institution from 1 January 2005 to 1 July 2013.

RESULTS

Three-hundred and seventy-one PSC patients were included. Compared with patients with UFP, those with MFP were more likely to have weight loss (32 vs. 9%), suspicious cytology (45 vs. 13%) and develop serial polysomy (91 vs. 35%). MFP was associated with CCA (hazard ratio (HR), 82.42; 95% confidence interval (CI), 24.50-277.31) and was the strongest predictor of cancer diagnosis. Suspicious cytology (HR, 26.31; 95% CI, 8.63-80.24) and UFP (HR, 13.27; 95% CI, 3.32-53.08) were also predictive of CCA. MFP, UFP and suspicious cytology remained associated with CCA in the multivariable model.

CONCLUSIONS

Compared with other FISH subtypes, MFP is the strongest predictor of CCA. However, patients with UFP and suspicious cytology (regardless of FISH status) are also at an increased risk for CCA.

[CLINICAL CASE OF COMBINATION OF PRIMARY SCLEROSING CHOLANGITIS WITH NONSPECIFIC ULCERATIVE COLITIS IN TWINS MONOZYGOTIC]

The article presents discussion of basic hypotheses of pathogenesis of primary sclerosing cholangitis (PSC): genetically conditioned pathology, autoimmune pathology, result of inflammatory reaction in bile ducts, cholangiopathy. The authors presents a clinical case of monozygotic twins with association of PSC and nonspecific ulcerative colitis (NUC). The first twin had a severe course of PSC and mild course of NUC; he died due to bacterial complications of cholangitis. The second twin--patient B--had an opposite situation: severe course of NUC, while PSC was suspected only after determination of cholestasis biochemical markers. As soon as cholestasis was revealed, patients B was treated with Ursofalk and Budenofalk (2001). He received Salofalk as a remedy of basic therapy for NUC. Repeated liver biopsy (2005) showed no progression of PSC, but there were present minimal biochemical signs of cholestasis. So, it is necessary to investigate the first degree relatives of patients with PSC. The timely administered treatment in some cases gives the possibility of the control of the disease course.

Difference from bile duct cancer and relationship between bile duct wall thickness and serum IgG/IgG4 levels in IgG4-related sclerosing cholangitis

BACKGROUND/AIMS

IgG4-related sclerosing cholangitis (IgG4-SC) is a newly established entity. The purpose of this study was to investigate the differences in intraductal ultrasonography (IDUS) findings between IgG4-SC and bile duct (BD) cancer (BDC) as well as the relationship among BD wall thickness, serological and pathological findings in IgG4-SC.

METHODOLOGY

Based on the diagnostic criteria of IgG4-SC, we reviewed patients in our hospital between April 2005 and June 2013, and analyzed the data obtained from 32 patients with IgG4-SC and 40 patients with BDC.

RESULTS

Regarding IDUS findings, significantly more cases in BDC indicated rigid/papillary inner margin than in IgG4-SC, while biopsy was more efficient. There were no significant correlations between BD wall thickness and serum IgG/IgG4 levels or the number of IgG4-positive cells of the BD specimens. All the IgG4-SC patients without steroid treatment revealed discordant results in the shifts of IgG, IgG4 and BD wall thickness between the 1st and 2nd examinations, while all patients with steroid had completely concordant results of the shifts.

CONCLUSIONS

IDUS findings alone are insufficient for differentiation between IgG4-SC and BDC. BD wall thickness, serum IgG and IgG4 proportionally shift and reflect the effect of steroid on IgG4-SC after steroid treatment, not before it.

In situ characterization of intrahepatic non-parenchymal cells in PSC reveals phenotypic patterns associated with disease severity

Liver-infiltrating T cells have been implicated in the pathogenesis of primary sclerosing cholangitis (PSC), however little information is available about changes in other cellular compartments in the liver during PSC. This study aimed to characterize non-parenchymal intrahepatic cells in PSC livers and to find associations between phenotypes and disease severity. Using immunohistochemistry, followed by automated image analysis and quantification and a principal component analysis, we have studied non-parenchymal intrahepatic cells in PSC-patient livers (n = 17) and controls (n = 17). We observed a significant increase of T cells in the PSC patients, localized to the fibrotic areas. MAIT cells, normally present at high numbers in the liver, were not increased to the same extent. PSC patients had lower expression of MHC class I than controls. However, the levels of NKp46+ NK cells were similar between patients and controls, nevertheless, NKp46 was identified as a phenotypic marker that distinguished PSC patients with mild from those with severe fibrosis. Beyond that, a group of PSC patients had lost expression of Caldesmon and this was associated with more extensive bile duct proliferation and higher numbers of T cells. Our data reveals phenotypic patterns in PSC patients associated with disease severity.

Primary sclerosing cholangitis and the microbiota: current knowledge and perspectives on etiopathogenesis and emerging therapies

Primary sclerosing cholangitis (PSC) is a chronic, fibroinflammatory, cholestatic liver disease of unknown etiopathogenesis. PSC generally progresses to liver cirrhosis, is a major risk factor for hepatobiliary and colonic neoplasia, and confers a median survival to death or liver transplantation of only 12 years. Although it is well recognized that approximately 75% of patients with PSC also have inflammatory bowel disease (IBD), the significance of this association remains elusive. Accumulating evidence now suggests a potentially important role for the intestinal microbiota, and enterohepatic circulation of molecules derived therefrom, as a putative mechanistic link between PSC and IBD and a central pathobiological driver of PSC. In this concise review, we provide a summary of and perspectives regarding the relevant basic, translational, and clinical data, which, taken together, encourage further investigation of the role of the microbiota and microbial metabolites in the etiopathogenesis of PSC and as a potential target for novel pharmacotherapies.

Is cetrimide-chlorhexidine risky for secondary sclerosing cholangitis?

BACKGROUND

The liver is the most frequent organ for placement of hydatid cyst disease. All known protoscolicidals that are used for echinococcus degeneration have a risk of caustic secondary sclerosing cholangitis. The cetrimide-chlorhexidine combination is an effective protoscolicidal agent for treatment of hydatid liver cysts.

OBJECTIVES

The aim of this experimental study was to examine this combination for potential risks of caustic secondary sclerosing cholangitis.

MATERIAL AND METHODS

Thirty rats were enrolled and divided into two groups. In the study group, 0.15 mL of a cetrimide (0.5%) and chlorhexidine (0.05%) combination was injected into the bile ducts for five minutes. The control group included the same amount of normal saline and waiting period. The rats were followed for 120 days and the living rats were examined for biliary injury by biochemical analysis and histopathology.

RESULTS

No specific histopathological findings for caustic sclerosing cholangitis such as bile duct stricture or periductal fibrosis were present in any groups. Other pathological criteria demonstrating inflammation including portal inflammation, bile duct proliferation and necrosis were similar in both groups. Biochemical analysis including a liver function test (aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, gamma-glutamyltranspeptidase) appeared similar to the control group.

CONCLUSIONS

A cetrimide 0.5% and chlorhexidine 0.05% combination has similar liver function results and histopathological effects to normal saline on bile ducts and it appears to be safe for bile ducts.

Inflammatory bowel disease of primary sclerosing cholangitis: A distinct entity?

This is a review of the characteristic findings of inflammatory bowel disease (IBD) associated with primary sclerosing cholangitis (PSC) and their usefulness in the diagnosis of sclerosing cholangitis. PSC is a chronic inflammatory disease characterized by idiopathic fibrous obstruction and is frequently associated with IBD. IBD-associated with PSC (PSC-IBD) shows an increased incidence of pancolitis, mild symptoms, and colorectal malignancy. Although an increased incidence of pancolitis is a characteristic finding, some cases are endoscopically diagnosed as right-sided ulcerative colitis. Pathological studies have revealed that inflammation occurs more frequently in the right colon than the left colon. The frequency of rectal sparing and backwash ileitis should be investigated in a future study based on the same definition. The cholangiographic findings of immunoglobulin G4-related sclerosing cholangitis (IgG4-SC) are similar to those of PSC. The rare association between IBD and IgG4-SC and the unique characteristics of PSC-IBD are useful findings for distinguishing PSC from IgG4-SC.

[Cytology is in pivotal role at screening and surveillance of PSC]

Primary sclerosing cholangitis (PSC) is an autoimmune disease leading to biliary strictures and inflammation. The lifetime risk for cholangiocarcinoma (CCA) among PSC patients is 7-13%, and biliary dysplasia is thought to be a precursor lesion for CCA. The diagnosis of PSC is based on endoscopic retrogradic cholangiography (ERC). During ERC brush cytology samples are routinely taken in our unit to detect possible biliary dysplasia. With repeated cytological dysplasia, liver transplantation is considered. Aneuploidy in DNA flow cytometry may support the suspicion of dysplasia. PSC is the most common indication for liver transplantation in Finland, and half of transplantations are prophylactic.