Sphingosine-1-phosphate promotes tumor development and liver fibrosis in mouse model of congestive hepatopathy.

BACKGROUND AND AIMS: Chronic liver congestion reflecting right-sided heart failure (RHF), Budd-Chiari syndrome, or Fontan-associated liver disease (FALD) is involved in liver fibrosis and HCC. However, molecular mechanisms of fibrosis and HCC in chronic liver congestion remain poorly understood. APPROACH AND RESULTS: Here, we first demonstrated that chronic liver congestion promoted HCC and metastatic liver tumor growth using murine model of chronic liver congestion by partial inferior vena cava ligation (pIVCL). As the initial step triggering HCC promotion and fibrosis, gut-derived lipopolysaccharide (LPS) appeared to induce LSECs capillarization in mice and in vitro. LSEC capillarization was also confirmed in patients with FALD. Mitogenic factor, sphingosine-1-phosphate (S1P), was increased in congestive liver and expression of sphingosine kinase 1, a major synthetase of S1P, was increased in capillarized LSECs after pIVCL. Inhibition of S1P receptor (S1PR) 1 (Ex26) and S1PR2 (JTE013) mitigated HCC development and liver fibrosis, respectively. Antimicrobial treatment lowered portal blood LPS concentration, LSEC capillarization, and liver S1P concentration accompanied by reduction of HCC development and fibrosis in the congestive liver. CONCLUSIONS: In conclusion, chronic liver congestion promotes HCC development and liver fibrosis by S1P production from LPS-induced capillarized LSECs. Careful treatment of both RHF and liver cancer might be necessary for patients with RHF with primary or metastatic liver cancer.

Peripheral-dominant liver fibrosis and tumor distribution in a mouse model of congestive hepatopathy.

AIM: Congestive hepatopathy often leads to liver fibrosis and hepatocellular carcinoma. Imaging modalities provided clinical evidence that elevation of liver stiffness and tumor occurrence are mainly induced in the periphery of the liver in patients with congestive hepatopathy. However, clinical relevance of liver stiffness and liver fibrosis is unclear because liver congestion itself increases liver stiffness in congestive hepatopathy. It also unclear which factors configure such regional disparity of tumor development in patients with congestive hepatopathy. To answer these questions, we evaluated the macroscopic spatial distribution of liver fibrosis and tumors in the murine model of congestive hepatopathy. METHODS: Chronic liver congestion was induced by partial ligation of the suprahepatic inferior vena cava. Distribution of liver congestion, fibrosis, and tumors in partial ligation of the suprahepatic inferior vena cava mice were assessed by histological findings, laser microdissection (LMD)-based qPCR and enhanced computed tomography. LMD-based RNA-sequencing was performed to identify causal factors that promote tumor development in congestive hepatopathy. RESULTS: Liver fibrosis was mainly induced in the periphery of the liver and co-localized with distribution of liver congestion. Liver tumors were also induced in the periphery of the liver where liver congestion and fibrosis occurred. LMD-based RNA-sequencing revealed the upregulation of extracellular matrix/collagen fibril-, wound healing-, angiogenesis-, morphogenesis-, and cell motility-related signaling pathways in periphery of liver compared with liver center. CONCLUSIONS: Our findings showed the experimental relevance of liver congestion, fibrosis, and tumor development in congestive hepatopathy, and may provide important locational information. Macroscopic regional disparity observed in this murine model should be considered to manage patients with congestive hepatopathy.

Signature of chronic hepatitis B virus infection in nails and hair.

BACKGROUND: Hepatitis B virus (HBV) is detected in extrahepatic tissues of individuals with HBV infection. Whether nails and hair contain HBV has been unknown. METHODS: We examined two patient groups: those with chronic HBV infection alone (n = 71), and those with both chronic HBV and hepatitis delta virus (HDV) infections (n = 15). HBV DNA in the patients' fingernails and hair were measured by real-time PCR. Hepatitis B surface antigen (HBsAg) of fingernails was evaluated by an enzyme immunoassay. HDV RNA in fingernails was measured by real-time PCR. Immunochemical staining was performed on nails. We used chimeric mice with humanized livers to evaluate the infectivity of nails. RESULTS: Of the 71 pairs of HBV-alone nail and hair samples, 70 (99%) nail and 60 (85%) hair samples were positive for ß-actin DNA. Of those 70 nail samples, 65 (93%) were HBV DNA-positive. Of the 60 hair samples, 49 (82%) were HBV DNA-positive. The serum HBV DNA level of the nail HBV DNA-positive patients was significantly higher than that of the nail HBV DNA-negative patients (p < 0.001). The hair HBV DNA-positive patients' serum HBV DNA level was significantly higher compared to the hair HBV DNA-negative patients (p < 0.001). The nail HBV DNA level was significantly higher than the hair HBV DNA level (p < 0.001). The nails and hair HBV DNA levels were correlated (r = 0.325, p < 0.05). A phylogenetic tree analysis of the complete genome sequence of HBV isolated from nails and hair identified the infection source. Of the 64 nail samples, 38 (59%) were HBsAg-positive. All 15 pairs of chronic HBV/HDV infection nail and hair samples were ß-actin DNA-positive. However, nail HBV DNA was detected in two patients (13%). None of the 15 patients were positive for hair HBV DNA. Nail HDV RNA was detected in three patients (20%). Of the 15 patients, eight (53%) were nail HBsAg-positive. HBsAg and hepatitis delta (HD) antigen were detected in the nails by immunochemical staining. Chimeric mice were not infected with PBS containing HBsAg and HBV DNA elucidated from nails. CONCLUSIONS: Nails and hair were the reservoir of HBV DNA. Moreover, nails can contain HBsAg, HDV RNA, and HD antigen.

Hepatitis B virus DNA in the fingernails and hair of children with acute hepatitis B.

Hepatitis B virus (HBV) DNA is detectable in the nails and hair of patients with chronic HBV infection. However, it remains unclear whether HBV DNA can be detectable in the nails and hair of patients with acute HBV infection. We encountered two cases of children with acute HBV infection. HBV DNA in the nails and hair from the two children was evaluated by real-time PCR. To clarify the characteristics of HBV DNA, full-length HBV genome sequencing and phylogenetic tree analysis were performed. The levels of serum HBV DNA in children of cases 1 and 2 at day 0 were 7.6 Log IU/mL and 7.4 Log IU/mL, respectively. Nail HBV DNA was detected in both children (case 1: 4.6 Log IU/mL at day 0, case 2: 5.5 Log IU/mL at day 14). Moreover, hair HBV DNA was detectable in case 2 (4.0 Log IU/mL at day 14). Serum HBV DNA became undetectable within approximately 3-4 months after the first hospital visit. After the resolution of HBV viremia, nail and hair HBV DNA became undetectable. The sequence analysis of serum, nail and hair HBV DNA showed the same HBV genotype in each case (case1: genotype C, case 2: genotype A). In case 1, 3 nucleotides were different in the full-genome HBV sequence between the serum and nails. In case 2, the full-genome HBV sequences were identical among the serum, nails and hair. In conclusion, HBV DNA was detectable in nails and hair of children with acute HBV infection.

Clinical features of pediatric eosinophilic gastroenteritis.

BACKGROUND: No study has analyzed more than100 cases of eosinophilic gastroenteritis (EGE) in children in a single center. We aimed to describe the clinical features of pediatric EGE. METHODS: This retrospective study was conducted at a single center. Between April 2007 and December 2017, 860 children between the ages of 1 year and 15 years underwent endoscopy for gastrointestinal symptoms of unknown cause. Among them, 109 (12.7%) were diagnosed with EGE according to the diagnostic criteria for EGE developed by the research group of the Ministry of Health, Labour and Welfare of Japan for eosinophilic gastrointestinal disorder in 2015. We investigated their symptoms, comorbidities, endoscopic findings, pathological findings, treatments, and outcomes. RESULTS: Seventy-one boys (65.1%) and 38 girls (34.9%) were diagnosed with EGE. The median age at diagnosis was 11 years (range, 1-15 years). The chief complaints were abdominal pain in 83 (76.1%) and diarrhea in 26 (23.9%). Upper and lower gastrointestinal endoscopies showed normal findings in 32 patients (29.4%). The most common treatment was a combination of elimination of foods suspected of causing EGE and anti-allergic agents in 50 cases (45.9%). The outcomes were symptom disappearance in 43 patients (39.4%) and symptom improvement in 53 patients (48.6%). CONCLUSIONS: For gastrointestinal symptoms of unknown cause in children, EGE should be considered as a differential diagnosis. Although the symptoms and endoscopic findings are nonspecific, cracked mucosa may be a specific endoscopic finding for pediatric EGE. An elimination diet and/or anti-allergic drugs were effective in most patients with pediatric EGE.

Loss of fibrocystin promotes interleukin-8-dependent proliferation and CTGF production of biliary epithelium.

BACKGROUND & AIMS: Congenital hepatic fibrosis (CHF) is a genetic liver disease resulting in abnormal proliferation of cholangiocytes and progressive hepatic fibrosis. CHF is caused by mutations in the PKHD1 gene and the subsequent dysfunction of the protein it encodes, fibrocystin. However, the underlying molecular mechanism of CHF, which is quite different from liver cirrhosis, remains unclear. This study investigated the molecular mechanism of CHF pathophysiology using a genetically engineered human induced pluripotent stem (iPS) cell model to aid the discovery of novel therapeutic agents for CHF. METHODS: PKHD1-knockout (PKHD1-KO) and heterozygously mutated PKHD1 iPS clones were established by RNA-guided genome editing using the CRISPR/Cas9 system. The iPS clones were differentiated into cholangiocyte-like cells in cysts (cholangiocytic cysts [CCs]) in a 3D-culture system. RESULTS: The CCs were composed of a monolayer of cholangiocyte-like cells. The proliferation of PKHD1-KO CCs was significantly increased by interleukin-8 (IL-8) secreted in an autocrine manner. IL-8 production was significantly elevated in PKHD1-KO CCs due to mitogen-activated protein kinase pathway activation caused by fibrocystin deficiency. The production of connective tissue growth factor (CTGF) was also increased in PKHD1-KO CCs in an IL-8-dependent manner. Furthermore, validation analysis demonstrated that both the serum IL-8 level and the expression of IL-8 and CTGF in the liver samples were significantly increased in patients with CHF, consistent with our in vitro human iPS-disease model of CHF. CONCLUSIONS: Loss of fibrocystin function promotes IL-8-dependent proliferation of, and CTGF production by, human cholangiocytes, suggesting that IL-8 and CTGF are essential for the pathogenesis of CHF. IL-8 and CTGF are candidate molecular targets for the treatment of CHF. LAY SUMMARY: Congenital hepatic fibrosis (CHF) is a genetic liver disease caused by mutations of the PKHD1 gene. Dysfunction of the protein it encodes, fibrocystin, is closely associated with CHF pathogenesis. Using an in vitro human induced pluripotent stem cell model and patient samples, we showed that the loss of fibrocystin function promotes proliferation of cholangiocytes and the production of connective tissue growth factor (CTGF) in an interleukin 8 (IL-8)-dependent manner. These results suggest that IL-8 and CTGF are essential for the pathogenesis of CHF.

Diabetic Retinopathy as a Risk Factor Associated with the Development of Hepatocellular Carcinoma in Nonalcoholic Fatty Liver Disease.

BACKGROUND: The risk factors associated with the development of hepatocellular carcinoma (HCC) in nonalcoholic fatty liver disease (NAFLD) are still unclear. The aim of the present study was to identify such risk factors in NAFLD patients who developed HCC. METHODS: Between April 2000 and -December 2016, a total of 182 patients with NAFLD were enrolled in this study; of these, only 22 patients had HCC. To identify risk factors, univariate and multivariate analyses were performed. To identify risk factors other than the degree of fibrosis, propensity matched analysis adjusted by the NAFLD fibrosis score (NFS) was carried out on 44 patients. Multivariate and survival analyses were also performed in HCC patients. RESULTS: In 182 patients, multivariate analysis highlighted the NFS (OR 2.275; p < 0.001) and hypertension (OR 5.868; p = 0.037) as independent factors that were significantly associated with the development of HCC. After adjustment for the NFS, multivariate analysis identified diabetic retinopathy (OR 8.654; p = 0.017) as an independent factor that was significantly associated with the development of HCC. For predicting the development of HCC, the area under the receiver operating characteristic curve of diabetic retinopathy was significantly higher than that of diabetes (0.731 vs. 0.615; p < 0.001). In patients with HCC, multivariate analysis indicated that the NFS were significantly associated with diabetic retinopathy. CONCLUSIONS: Diabetic retinopathy as well as liver fibrosis is a risk factor that associates with the development of HCC in NAFLD patients. Therefore, NAFLD patients with diabetic retinopathy should undergo careful screening for HCC.

Long-term outcomes of pediatric-onset primary sclerosing cholangitis: A single-center experience in Japan.

AIM: Primary sclerosing cholangitis (PSC) is very rare in Japan. Although a large-scale cohort study of 781 pediatric-onset PSC patients in Europe and North America showed that the 5-year survival with native liver was 88%, the long-term outcomes of pediatric-onset PSC in Japan are unknown. Here, we evaluated the clinical outcomes of pediatric-onset PSC in Japan. METHODS: We carried out a retrospective cohort study with a medical records review of pediatric PSC patients diagnosed between 1986 and 2017 at a single center. The PSC diagnoses were based on cholangiography, liver histology, and biochemical findings. The patients' survival was analyzed using the Kaplan-Meier method. Prognostic factors were determined by univariate and multivariate analyses using the Cox proportional hazards regression model. RESULTS: We identified 39 pediatric-onset PSC patients (22 boys, 17 girls). The median age at diagnosis was 9 years (interquartile range 6.0-13.5 years). The median follow-up period was 5.5 years (interquartile range 3.4-8.7 years). The phenotypes of PSC-autoimmune hepatitis, PSC-inflammatory bowel disease, and small-duct PSC were diagnosed in 13 (33.3%), 36 out of 38 (94.8%), and three (7.7%) patients, respectively. The 5-year liver transplantation-free survival of the whole cohort was 93.5%. Nine patients underwent liver transplantation, and four of these nine cases resulted in death. Both the univariate and multivariate analyses showed that the phenotype of "PSC-autoimmune hepatitis overlap" was an independent poor prognostic factor. CONCLUSIONS: The overall survival of pediatric-onset PSC in Japan was comparable to those in Western countries. The phenotype of PSC-autoimmune hepatitis was identified as a prognostic factor associated with a poorer long-term outcome.

Association of serum interferon-λ3 levels with hepatocarcinogenesis in chronic hepatitis C patients treated with direct-acting antiviral agents.

AIM: Although the efficacy of hepatitis C virus (HCV) treatment is improved dramatically by direct-acting antiviral agents (DAAs), the assessment of hepatocellular carcinoma (HCC) remains important. Interferon lambda 3 (IFN-λ3) is associated with liver fibrosis and inflammation in chronic hepatitis C (CHC) patients, but its impact on carcinogenesis remains controversial and little is known about its effects after viral clearance. To determine the contribution of IFN-λ3 to hepatocarcinogenesis after HCV clearance, we analyzed IFNL3 genotypes and serial serum IFN-λ3 levels in CHC patients who achieved sustained virologic responses (SVR). METHODS: This study comprised 201 CHC patients treated with DAAs. Serum samples were collected sequentially and IFN-λ3 levels were quantified by chemiluminescence enzyme immunoassay. The IFNL3 polymorphism (rs8099917) was genotyped in 195 patients. RESULTS: One hundred and twenty-five patients were rs8099917 T/T and 70 were non-T/T. Serum IFN-λ3 levels did not differ significantly with IFNL3 genotype, dropped markedly by 1 week and remained low up to 24 weeks after the end of treatment. Interferon-λ3 levels were significantly higher after viral clearance in patients who developed HCC and were associated with a higher potential for hepatocarcinogenesis, such as a higher frequency of non-hypervascular hypointensive nodules (P = 0.046), higher stages of liver fibrosis (P < 0.001), and higher post-treatment levels of Wisteria floribunda agglutinin positive Mac-2 binding protein (P < 0.001) and alanine aminotransferase (P < 0.001). CONCLUSIONS: Serum IFN-λ3 levels after HCV clearance are associated with the potential for HCC development. Interferon-λ3 could be helpful for elucidating the relationships among immunologic status, liver fibrosis, liver inflammation, and hepatocarcinogenesis, after achieving SVR.

Comprehensive genetic analysis of cholangiolocellular carcinoma with a coexistent hepatocellular carcinoma-like area and metachronous hepatocellular carcinoma.

AIM: The genetic profile of cholangiolocellular carcinoma (CLC) and its origin in relation to hepatocellular carcinoma (HCC) remain unclear. To elucidate the genetic profile of CLC, a comprehensive analysis of genetic mutations was carried out in a case of CLC with an HCC-like focal area and metachronous HCC. METHOD: Liver tissue was obtained from CLC, a co-existent HCC-like area, and metachronously developed HCC by laser capture microdissection of formalin-fixed paraffin-embedded specimens obtained by hepatectomy. Gene mutational profiles were analyzed comprehensively by next-generation sequencing and digital PCR. Relationships among gene profiles, immunohistochemistry, and clinicopathological findings were investigated. RESULTS: Mutations in EGFR, PTEN, RB1, TP53, and ERBB2 were found in CLC, whereas mutations in KIT, BRAF, PTEN, TP53, and SMAD4 were found in the coexistent HCC-like area. Only the mutation in PTEN has a common Catalogue of Somatic Mutations in Cancer ID in the CLC and coexistent HCC-like area, and is related to the kinase-RAS module. In contrast, no cancer-related mutations were found in the metachronous HCC. No TERT mutations were found in any of the regions by digital PCR. Immunohistochemical staining for p53 was negative in CLC, although ≤10% positive in the coexistent HCC-like area. Immunostaining of C-kit, HER2, PTEN, and SMAD4 were negative. CONCLUSION: The genomic features of CLC and the focal area of an HCC-like region differ, but are related to the kinase-RAS module. The development of carcinogenesis in the CLC and HCC-like areas in this case might differ, following a common PTEN mutation, although alteration of the kinase-RAS module is the most common molecular event in CLC.

Effect of interferon-based and -free therapy on early occurrence and recurrence of hepatocellular carcinoma in chronic hepatitis C.

BACKGROUND AND AIMS: Although treatment for hepatitis C virus has been dramatically improved by the development of direct-acting antiviral agents (DAAs), whether interferon (IFN)-free therapy reduces hepatocarcinogenesis in an equivalent manner to IFN-based therapy remains controversial. The aims of this study were to evaluate the occurrence and recurrence of hepatocellular carcinoma (HCC) in chronic hepatitis C (CHC) patients treated with DAAs and to identify biomarkers of HCC development after antiviral treatment. METHODS: A restrospective review of a prospective database of 1,897 CHC patients who were treated with IFN-based (1,145) or IFN-free therapies (752) was carried out. Cumulative HCC occurrence and recurrence rates were compared using propensity score-matched analysis. Predictors of HCC development after viral eradication were identified by multivariate analysis. RESULTS: Propensity score-matched analysis showed no significant difference in HCC occurrence (p=0.49) and recurrence rates (p=0.54) between groups treated with IFN-based or IFN-free therapies. In multivariate analysis, higher levels of post-treatment α-fetoprotein (AFP) or Wisteria floribunda agglutinin positive Mac-2 binding protein (WFA+M2BP) were independently associated with HCC occurrence and recurrence after viral eradication. Only post-treatment WFA+M2BP level was significantly associated with HCC occurrence and recurrence among patients without severe fibrosis. The area under the receiver operating characteristic (ROC) curve for WFA+M2BP levels was greater than that for AFP levels in ROC analysis. CONCLUSION: The risks of early HCC occurrence and recurrence after viral eradication were similar between IFN-based and IFN-free therapies. Post-treatment levels of WFA+M2BP may be helpful screening biomarkers for assessing the risk of HCC after IFN-free therapy. Patients with high WFA+M2BP levels after antiviral treatment, even without severe fibrosis, must be followed up carefully for HCC development. Lay summary: The risks of early HCC occurrence and recurrence after viral eradication were similar between IFN-based and IFN-free therapies. Post-treatment levels of WFA+M2BP may be helpful screening biomarkers for assessing the risk of HCC after IFN-free therapy.

Hepatic IFNL4 expression is associated with non-response to interferon-based therapy through the regulation of basal interferon-stimulated gene expression in chronic hepatitis C patients.

Single nucleotide polymorphisms (SNPs) within or near interferon lambda 4 (IFNL4) gene located upstream of IFNL3 are associated with response to anti-HCV therapy both in interferon (IFN)-based and IFN-free regimens. IFNL4 encodes IFNλ4, a newly discovered type III IFN, and its expression is controlled by rs368234815-TT/ΔG, which is in strong linkage disequilibrium (LD) with other tag SNPs within or near IFNL4 such as rs12979860 and rs8099917. Intrahepatic expression levels of IFN-stimulated genes (ISGs) affect the responsiveness to IFNα and are also associated with IFNL4 genotype. However, IFNL4 expressions and its role in intrinsic antiviral innate immunity remain unclear. This study evaluated the effect of IFNL4 on intrahepatic ISG expression and investigated its relationship with treatment outcomes in liver samples obtained from 49 chronic hepatitis C patients treated with pegylated (PEG)-IFN/ribavirin therapy. IFNL4 mRNA was detected in 11 of 22 patients with IFNL4-unfavorable SNPs but not in patients with favorable genotypes. IFNL4 expression was associated with non-response to PEG-IFN/ribavirin therapy. Intrahepatic expression of antiviral ISGs (ISG15 and MX1) was significantly higher in IFNL4-unfavorable patients with detectable IFNL4 mRNA than in patients with undetectable IFNL4 mRNA, whereas the expression of suppressive ISGs (RNF125, SOCS1, SOCS3, and RNF11) was lower in patients with detectable IFNL4 mRNA. In summary, intrahepatic expression of IFNL4 was associated with increased antiviral ISG expression and decreased suppressive ISG expression at baseline, resulting in poor responsiveness to IFNα-based therapy in HCV infection.

ITPA gene variation and ribavirin-induced anemia in patients with genotype 2 chronic hepatitis C treated with sofosbuvir plus ribavirin.

AIM: Sofosbuvir (SOF) and ribavirin (RBV) combination therapy produces a sustained response in many patients with genotype 2 chronic hepatitis C. However, RBV-induced anemia is a troublesome side-effect that may limit this treatment. Genetic variation leading to inosine triphosphatase (ITPA) deficiency is known to protect against RBV-induced hemolytic anemia. This study aimed to evaluate the relationships between the efficacy and safety of SOF/RBV treatment and ITPA gene variants. METHODS: Ninety patients with genotype 2 chronic hepatitis C treated with SOF/RBV were studied. The relationships among genetic polymorphisms of ITPA and the decline in hemoglobin levels from baseline, RBV dose reduction, and sustained virological response (SVR) rates were analyzed. RESULTS: Overall SVR at 12 weeks was 94.4% (85/90). Patients with the ITPA CA/AA genotypes had a lower degree of anemia throughout the therapy than those with the ITPA CC genotype. The percentage of patients requiring RBV dose reduction was significantly lower for those with the ITPA CA/AA variation, a difference even more apparent when the pretreatment hemoglobin level was <12 g/dL. The dose reduction of RBV and serum albumin level were significantly associated with SVR. CONCLUSIONS: Patients with the ITPA CA/AA genotype were less likely to develop anemia than those with the ITPA CC genotype and were more likely to complete SOF/RBV therapy. These results may provide a valuable pharmacogenetic diagnostic tool to predict drug-induced adverse events, particularly in patients with pre-existing anemia.

Bone morphogenetic protein-4 modulates proliferation and terminal differentiation of fetal hepatic stem/progenitor cells.

Fetal hepatic stem/progenitor cells, called hepatoblasts, play central roles in liver organogenesis; however, molecular mechanisms regulating proliferation and terminal differentiation of such cells have not been completely elucidated. Bone morphogenetic protein-4 (BMP-4) is essential for the development of stem cells in various tissues, but its function in regulating the phenotype of hepatoblasts after the mid-gestational fetal stage remains unclear. The aim of this study is to clarify a functional role for BMP-4 in proliferation and terminal differentiation of murine hepatoblasts in mid-gestational fetal livers. METHODS: A functional role for BMP-4 in proliferation and terminal differentiation of murine hepatoblasts was validated by assay of colony formation, biliary luminal formation, and hepatic maturation using primary hepatoblasts in vitro. Molecular mechanisms regulating such effects of BMP-4 on primary hepatoblasts were also analyzed. RESULTS: Stimulation of BMP-4 upregulated phosphorylation of Smad1/5 in hepatoblasts. Bone morphogenetic protein-4 significantly suppressed colony formation of primary hepatoblasts in a dose-dependent manner, significantly suppressed cholangiocytic luminal formation of hepatoblasts, and promoted hepatic maturation of primary hepatoblasts. Stimulation of BMP-4 regulated the activation of several mitogen-activated protein kinases, such as extracellular signal-regulated kinase, Akt, p38 mitogen-activated protein kinase, and calcium/calmodulin-dependent protein kinase IIα in primary hepatoblasts. Moreover, Wnt5a, a molecule regulating cholangiocytic luminal formation, and BMP-4 coordinately suppressed proliferation and cholangiocytic luminal formation of hepatoblasts. CONCLUSION: This study shows that BMP-4-mediated signaling controls proliferation and terminal differentiation of fetal hepatic stem/progenitor cells.

Acute liver dysfunction not resulting from hepatitis virus in immunocompetent children.

BACKGROUND: The aim of the present study was to clarify the roles of cytomegalovirus (CMV), Epstein-Barr virus (EBV), and human herpesvirus 6 (HHV-6) in immunocompetent children with acute liver dysfunction not resulting from hepatitis virus. METHODS: Sixty-eight children (median age, 3 years) hospitalized as a result of acute liver dysfunction were enrolled in this study. Hepatitis A, B, and C were excluded. The prevalence of CMV, EBV, and HHV-6 and viral DNA load in whole blood was prospectively evaluated on multiplex real-time polymerase chain reaction (PCR). RESULTS: Of the 68 children with acute liver dysfunction, multiplex real-time PCR was positive in 30 (44%). CMV, EBV, and HHV-6 DNA were detected in 13 (19%), 14 (21%), and seven (10%), respectively. Serum CMV immunoglobulin (Ig)G/IgM and EBV viral capsid antigen IgG/IgM were measured in 40 (CMV DNA positive, n = 10; negative, n = 30) and 45 (EBV DNA positive, n = 14; negative, n = 31) of the 68 children, respectively. Eighteen percent (CMV, 7/40) and 9% (EBV, 4/45) were positive for both PCR and viral-specific IgM. There was no significant difference in CMV and EBV viral load between IgM-positive and -negative children with viremia. CONCLUSIONS: CMV, EBV, and HHV-6 DNA were frequently detected in immunocompetent children with acute liver dysfunction, but primary CMV and EBV infection were confirmed in 10-20% of the children with acute liver dysfunction. The combination of PCR assay and serology is necessary to make a diagnosis of acute liver dysfunction due to primary CMV, EBV and/or HHV-6 infection in immunocompetent children.

Feasibility and safety of bowel cleansing using low-volume polyethylene glycol with ascorbic acid before pediatric colonoscopy: A pilot study.

BACKGROUND AND AIM: To assess the feasibility and safety of same-day regimen of low-volume polyethylene glycol solution with ascorbic acid for bowel cleansing before colonoscopy in children. METHODS: Data on children who received polyethylene glycol solution with ascorbic acid for bowel cleansing in our department were retrospectively analyzed. On the day before the procedure, patients ate a low-residue diet and received sodium picosulfate in the evening. The following day, patients took polyethylene glycol solution with ascorbic acid in the morning; the procedure was carried out in the afternoon. Dosages of sodium picosulfate and polyethylene glycol solution with ascorbic acid were adjusted based on bodyweight. Bowel cleansing efficacy was rated on a scale of 1-5 by the colonoscopist. RESULTS: Between July 2013 and November 2014, polyethylene glycol solution with ascorbic acid was used in 112 cases (96 patients; male : female 73:39; median age 10.9 years, range 4-19 years). Ninety-one cases (81%) were able to orally ingest the prescribed amount of polyethylene glycol solution with ascorbic acid. Satisfactory bowel cleansing (cleansing grade ≥3) was attained in 87% on intention-to-treat analysis and 85% on per-protocol analysis. Cleansing grade was significantly better in children who ingested polyethylene glycol solution with ascorbic acid within 60 min (P < 0.05). There were no serious adverse events. CONCLUSION: Same-day regimen of polyethylene glycol solution with ascorbic acid is effective and safe for bowel cleansing in children.

Matrix metalloproteinase-14 mediates formation of bile ducts and hepatic maturation of fetal hepatic progenitor cells.

Fetal hepatic stem/progenitor cells, called hepatoblasts, play central roles in liver development; however, the molecular mechanisms regulating the phenotype of these cells have not been completely elucidated. Matrix metalloproteinase (MMP)-14 is a type I transmembrane proteinase regulating pericellular proteolysis of the extracellular matrix and is essential for the activation of several MMPs and cytokines. However, the physiological functions of MMP-14 in liver development are unknown. Here we describe a functional role for MMP-14 in hepatic and biliary differentiation of mouse hepatoblasts. MMP-14 was upregulated in cells around the portal vein in perinatal stage liver. Formation of bile duct-like structures in MMP-14-deficient livers was significantly delayed compared with wild-type livers in vivo. In vitro biliary differentiation assays showed that formation of cholangiocytic cysts derived from MMP-14-deficient hepatoblasts was completely impaired, and that overexpression of MMP-14 in hepatoblasts promoted the formation of bile duct-like cysts. In contrast, the expression of molecules associated with metabolic functions in hepatocytes, including hepatic nuclear factor 4α and tryptophan 2,3-dioxygenase, were significantly increased in MMP-14-deficient livers. Expression of the epidermal growth factor receptor and phosphorylation of mitogen-activated protein kinases were significantly upregulated in MMP-14-deficient livers. We demonstrate that MMP-14-mediated signaling in fetal hepatic progenitor cells promotes biliary luminal formation around the portal vein and negatively controls the maturation of hepatocytes.

Neonatal liver failure owing to gestational alloimmune liver disease without iron overload.

Although neonatal hemochromatosis (NH) is a well-known cause of liver failure during the neonatal period and iron deposition in extrahepatic tissues is considered essential in the diagnosis of NH, there is no consensus regarding the pathology or diagnostic criteria of NH. Recent studies of immunohistochemical assays have shown that the C5b-9 complex (the terminal membrane attack complement complex) is strongly expressed in the liver of NH cases, suggesting that a gestational alloimmune mechanism is the cause of liver injury. The patient was a low birthweight primiparous male born at 37 weeks of gestation by vaginal delivery. Blood tests 3 h after birth showed signs of liver failure, including high transferrin saturation, resembling the clinical characteristics of NH. However, magnetic resonance imaging and a lip biopsy showed no obvious iron deposition outside the liver. The patient was refractory to exchange transfusion and immunoglobulin therapy but was successfully treated by liver transplantation. Histologically, the explanted liver showed established cirrhosis, with large amounts of human C5b-9 in the residual hepatocytes, suggesting the alloimmune mechanism of liver injury was the cause of his liver failure. Liver failure caused by a gestational alloimmune mechanism should be considered in patients with antenatal liver failure, even without obvious extrahepatic siderosis.

Chronic hepatitis B virus infection in children and adolescents in Japan.

BACKGROUND: Hepatitis B e antigen (HBeAg) seroconversion is an important event in patients with chronic hepatitis B virus (HBV) infection. This study aimed to clarify the outcome of long-term follow-up of chronic HBV infection and the factors affecting HBeAg seroconversion in children in Japan. METHODS: Patients who were first examined at our institution between 1980 and 2012, who were <20 years of age at the time of this initial visit, and who were positive for hepatitis B surface antigen for at least 6 months were identified retrospectively. Sex, age at diagnosis, HBV genotype, maximum serum alanine aminotransferase (ALT) level, occurrence of hepatitis flare-ups (yes/no), and transmission route were evaluated to identify the predictors of HBeAg seroconversion. RESULTS: A total of 205 children with chronic HBV were enrolled. Among them, 192 were positive for HBeAg upon diagnosis of chronic HBV infection. Out of this group, 95 (49%) achieved HBeAg seroconversion and 43 (21%) received treatment during the follow-up period. Only the maximum serum ALT level was significantly associated with the achievement of HBeAg seroconversion by multivariate analysis (P < 0.05). Kaplan-Meier analysis showed that the median times to HBeAg seroconversion (50% achievement of HBeAg seroconversion) of the treated and untreated children were 10.2 and 12.0 years, respectively. The cumulative proportion of HBeAg seroconversion was significantly higher in the treated children than in the untreated children (P = 0.02). CONCLUSIONS: A higher serum ALT level was a predictor for HBeAg seroconversion. Antiviral treatment could accelerate the achievement of HBeAg seroconversion in HBV-infected children.

Hepatitis B (HB) immunoglobulin plus HB vaccine for intrauterine HB virus infection.

BACKGROUND: Vaccination against hepatitis B virus (HBV) infection in infants born to hepatitis B surface antigen (HBsAg)-positive mothers using HB immunoglobulin (HBIG) and hepatitis B (HB) vaccine was launched in Japan in 1985. Infants testing positive for HBsAg at 1 month of age are considered to have prenatally acquired the infection and are usually excluded from the prevention program. Infants born to HB e antigen (HBeAg)-positive mothers are at a high risk of perinatally acquiring the infection. In this study, long-term outcome was evaluated in children with prenatal HBV infection who received the HBIG and HB vaccine in Japan. METHODS: Newborns of both HBsAg- and HBeAg-positive carrier mothers received HBIG within 48 h of birth and at 2 months of age. Subsequently, three doses of recombinant HB vaccine were given at 2, 3, and 5 months of age. Outcome was compared between the following two groups: infants who completed the vaccination program, even if they were HBsAg positive at 1 month of age (n = 15), and infants who did not (n = 51). RESULTS: Seroconversion from HBeAg to anti-HBe antibody (HBeAb) before 3 years of age was observed in five children (33%) who completed the vaccination program and in two (4%) who did not (P = 0.005). In 2/5 children who completed the vaccination program and achieved HBeAb seroconversion, seroconversion from HBsAg to anti-HBs antibody was also noted. CONCLUSION: This specific vaccination program for children with prenatal HBV infection has the potential to alter immune tolerance to HBV.