Possible involvement of mucosal-associated invariant T cells in the progression of inflammatory bowel diseases.

Mucosal-associated invariant T (MAIT) cells are innate-like T cells involved in anti-bacterial immunity. Recent studies have demonstrated that MAIT cells might be implicated in inflammatory bowel diseases (IBDs), but their precise function in IBD remains to be elucidated. We investigated the possible involvement of MAIT cells in the immunopathogenesis of IBDs. Heparinized peripheral blood and biopsy specimens of the colon were collected from 25 patients with ulcerative colitis (UC), 15 patients with Crohn's disease (CD), and 19 heathy individuals. Lymphocytes were isolated from the blood and colon, and then MAIT cells were analyzed by flow cytometry. The frequency of MAIT cells was significantly lower in the blood of IBD patients compared to healthy donors and significantly higher in the inflamed colons compared to healthy colons (P = 0.001). Among the IBD patients, the frequency of MAIT cells in the blood and colon was correlated with disease activities. In vitro activated MAIT cells from IBD patients secreted significantly more tumor necrosis factor-α and interleukin-17 than those from healthy donors. These findings indicate that MAIT cells are activated in IBD patients, and their accumulation in the inflamed mucosa is correlated with disease activities.

Proposed criteria to differentiate heterogeneous eosinophilic gastrointestinal disorders of the esophagus, including eosinophilic esophageal myositis.

AIM: To define clinical criteria to differentiate eosinophilic gastrointestinal disorder (EoGD) in the esophagus. METHODS: Our criteria were defined based on the analyses of the clinical presentation of eosinophilic esophagitis (EoE), subepithelial eosinophilic esophagitis (sEoE) and eosinophilic esophageal myositis (EoEM), identified by endoscopy, manometry and serum immunoglobulin E levels (s-IgE), in combination with histological and polymerase chain reaction analyses on esophageal tissue samples. RESULTS: In five patients with EoE, endoscopy revealed longitudinal furrows and white plaques in all, and fixed rings in two. In one patient with sEoE and four with EoEM, endoscopy showed luminal compression only. Using manometry, failed peristalsis was observed in patients with EoE and sEoE with some variation, while EoEM was associated with hypercontractile or hypertensive peristalsis, with elevated s-IgE. Histology revealed the following eosinophils per high-power field values. EoE = 41.4 ± 7.9 in the epithelium and 2.3 ± 1.5 in the subepithelium; sEoE = 3 in the epithelium and 35 in the subepithelium (conventional biopsy); EoEM = none in the epithelium, 10.7 ± 11.7 in the subepithelium (conventional biopsy or endoscopic mucosal resection) and 46.8 ± 16.5 in the muscularis propria (peroral esophageal muscle biopsy). Presence of dilated epithelial intercellular space and downward papillae elongation were specific to EoE. Eotaxin-3, IL-5 and IL-13 were overexpressed in EoE. CONCLUSION: Based on clinical and histological data, we identified criteria, which differentiated between EoE, sEoE and EoEM, and reflected a different pathogenesis between these esophageal EoGDs.

Phase 1 Clinical Study of siRNA Targeting Carbohydrate Sulphotransferase 15 in Crohn's Disease Patients with Active Mucosal Lesions.

BACKGROUND AND AIMS: Carbohydrate sulphotransferase 15 [CHST15] is a specific enzyme biosynthesizing chondroitin sulphate E that binds various pathogenic mediators and is known to create local fibrotic lesions. We evaluated the safety of STNM01, a synthetic double-stranded RNA oligonucleotide directed against CHST15, in Crohn's disease [CD] patients whose mucosal lesions were refractory to conventional therapy. METHODS: This was a randomized, double-blind, placebo-controlled, concentration-escalation study of STNM01 by a single-dose endoscopic submucosal injection in 18 CD patients. Cohorts of increasing concentration of STNM01 were enrolled sequentially as 2.5nM [n = 3], 25nM [n = 3], and 250nM [n = 3] were applied. A cohort of placebo [n = 3] was included in each concentration. Safety was monitored for 30 days. Pharmacokinetics was monitored for 24h. The changes from baseline in the segmental Simple Endoscopic Score for CD [SES-CD] as well as the histological fibrosis score were evaluated. RESULTS: STNM01 was well tolerated and showed no drug-related adverse effects in any cohort of treated patients. There were no detectable plasma concentrations of STNM01 at all measured time points in all treatment groups. Seven of nine subjects who received STNM01 showed reduction in segmental SES-CD at Day 30, when compared with those who received placebo. Histological analyses of biopsy specimens revealed that STNM01 reduced the extent of fibrosis. CONCLUSION: Local application of STNM01 is safe and well tolerated in CD patients with active mucosal lesions.

Endoscopic Removal of Ingested Dentures and Dental Instruments: A Retrospective Analysis.

Background. Dentures and dental instruments are frequently encountered ingested foreign bodies. The aim of the present study was to assess the safety and efficacy of endoscopically removing ingested dental objects. Methods. Twenty-nine consecutive patients with 29 dental objects who were treated at the Niigata University Medical and Dental Hospital from August 2009 to December 2015 were retrospectively reviewed. Characteristics of the patients and the ingested dental objects, the clinical features and findings of radiological imaging tests, and outcomes of endoscopic removal were analyzed. Results. Patients' mean age was 62.9 ± 21.0 years. The ingested dental objects included 23 dentures (13 crowns, 4 bridges, 4 partial dentures, and 2 other dentures) and 6 dental instruments. Twenty-seven upper gastrointestinal endoscopies and 2 colonoscopies were performed, and their success rates were 92.6% and 100%, respectively. There were 2 cases of removal failure; one case involved an impacted partial denture in the cervical esophagus, and this case required surgical removal. Conclusions. Endoscopic removal of ingested dentures and dental instruments is associated with a favorable success rate and acceptable complications. The immediate intervention and appropriate selection of devices are essential for managing ingested dental objects.

Pivotal Role of Carbohydrate Sulfotransferase 15 in Fibrosis and Mucosal Healing in Mouse Colitis.

Induction of mucosal healing (MH) is an important treatment goal in inflammatory bowel disease (IBD). Although the molecular mechanisms underlying MH in IBD is not fully explored, local fibrosis would contribute to interfere mucosal repair. Carbohydrate sulfotransferase 15 (CHST15), which catalyzes sulfation of chondroitin sulfate to produce rare E-disaccharide units, is a novel mediator to create local fibrosis. Here we have used siRNA-based approach of silencing CHST15 in dextran sulfate sodium (DSS) induced colitis in mice, human colon fibroblasts and cancer cell lines. In a DSS-induced acute colitis model, CHST15 siRNA reduced CHST15 mRNA in the colon, serum IL-6, disease activity index (DAI) and accumulation of F4/80+ macrophages and ER-TR7+ fibroblasts, while increased Ki-67+ epithelial cells. In DSS-induced chronic colitis models, CHST15 siRNA reduced CHST15 mRNA in the colon, DAI, alpha-smooth muscle actin+ fibroblasts and collagen deposition, while enhanced MH as evidenced by reduced histological and endoscopic scores. We also found that endoscopic submucosal injection achieved effective pancolonic delivery of CHST15 siRNA in mice. In human CCD-18 Co cells, CHST15 siRNA inhibited the expression of CHST15 mRNA and selectively reduced E-units, a specific product biosynthesized by CHST15, in the culture supernatant. CHST15 siRNA significantly suppressed vimentin in both TGF-ß-stimulated CCD18-Co cells and HCT116 cells while up-regulated BMP7 and E-cadherin in HCT116 cells. The present study demonstrated that blockade CHST15 represses colonic fibrosis and enhances MH partly though reversing EMT pathway, illustrating a novel therapeutic opportunity to refractory and fibrotic lesions in IBD.

A murine model for non-alcoholic steatohepatitis showing evidence of association between diabetes and hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related deaths. In addition to hepatitis viral infections, several cohort studies have shown that diabetes mellitus is a risk factor of HCC, making the incidence alarming high. However, it has not been demonstrated directly how diabetes develops to HCC, because of its difficulty to follow changes of liver histology in diabetic populations. Here, we report that non-alcoholic steatohepatitis (NASH) is pivotal to link diabetes with HCC by establishing a novel, reproducible NASH-HCC model in mice. Neonatal male mice exposed to low-dose streptozotocin (STZ) developed liver steatosis with diabetes 1 week after feeding high-fat diet (HFD). Continuous HFD decreased hepatic fat deposit whilst increased lobular inflammation with foam cell-like macrophages, showing NASH pathology. In parallel with decreased phagocytosis of macrophages, fibroblasts accumulated to form "chicken-wired" fibrosis. All mice developed multiple HCC later. Female mice treated with STZ-HFD and male mice treated with STZ alone showed diabetes but never developed HCC by the absence of NASH-based fibrosis. Thus, the present study provides the evidence in novel mouse model that NASH-based fibrosis is an essential histological process for diabetic populations to accelerate the development of HCC.

Familial juvenile polyposis syndrome with a novel SMAD4 germline mutation.

Juvenile polyposis syndrome (JPS) is a dominantly inherited disorder characterized by the development of numerous juvenile polyps (JPs) of the gastrointestinal tract, and associated with a mutation of the SMAD4 or BMPR1A gene. Here, we report a mother-daughter case of familial JPS. A 29-year-old female patient with severe iron deficiency anemia and hypoproteinemia had numerous polyps in the stomach and a few polyps in the ileum and colon that were detected endoscopically. Biopsy specimens from the gastric polyps were diagnosed as JPs. The patient underwent a laparoscopy-assisted total gastrectomy, and her anemia and hypoproteinemia improved. Her mother also had multiple JPs in the stomach, duodenum, jejunum, and colon. We then diagnosed them as having familial JPS. Moreover, germline mutation analysis of the 2 patients presented a novel pathogenic SMAD4 variant.

Sustained response to interferon-alpha plus ribavirin therapy for chronic hepatitis C is closely associated with increased dynamism of intrahepatic natural killer and natural killer T cells.

AIM: Previous studies have revealed that functional impairment of innate immune cells, including natural killer (NK) and natural killer T (NKT) cells, might be associated with the persistence of hepatitis C virus (HCV) infection. However, the involvement of innate immune cells, which predominate in the liver, in therapeutic HCV clearance is still unclear. METHODS: To clarify the role of intrahepatic innate immune cells in the clinical outcome of patients with chronic hepatitis C (CHC) treated with interferon-alpha plus ribavirin (IFN/RBV), we prospectively investigated the status of NK and NKT cells in paired liver biopsy and peripheral blood (PB) samples obtained from 21 CHC patients before and immediately after IFN/RBV treatment by flow cytometry. Normal liver and PB samples were obtained from 10 healthy donors for living donor liver transplantation. RESULTS: Before treatment, intrahepatic NK and NKT cells constituted a significantly lower proportion in CHC patients than in healthy individuals (P < 0.05). After IFN/RBV treatment, the proportions and absolute numbers of CD3(-)CD161(+) NK and CD3(+)CD56(+) NKT cells in the liver, but not in PB, were significantly increased in sustained responders (SR) as compared with poor responders (P < 0.05). The proportion of CD3(+)CD161(+) NKT cells was also increased in the liver of SR after the treatment. Moreover, there was a striking increase of activated CD152(+) cells among CD3(+)CD56(+) NKT cells in the liver of SR (P = 0.041). CONCLUSION: These findings demonstrate that sustained response to IFN/RBV treatment for patients with CHC is closely associated with increased dynamism of NK and NKT cells in the liver.

An inhibitor of c-Jun NH2-terminal kinase, SP600125, protects mice from D-galactosamine/lipopolysaccharide-induced hepatic failure by modulating BH3-only proteins.

Fulminant hepatic failure (FHF) is a dramatic clinical syndrome characterized by massive hepatocyte apoptosis and very high mortality. The c-Jun-N-terminal kinase (JNK) pathway is an important stress-responsive kinase activated by several forms of liver injury. The aim of this study is to assess the role of JNK during D-galactosamine (GalN)/lipopolysaccharide (LPS)-induced liver injury, an experimental model of FHF, using SP600125, a small molecule JNK-specific inhibitor. Mice were given an intraperitoneal dose of GalN (800 microg/g body weight)/LPS (100 ng/g body weight) with and without subcutaneous SP600125 (50 mg/kg body weight) treatment (at 6 and 2 h before and 2 h after GalN/LPS administration). GalN/LPS treatment induced sustained JNK activation. Administration of SP600125 diminished JNK activity, suppressed lethality and the elevation of both serum alanine aminotransferase and aspartate aminotransferase, but had no effect on serum tumor necrosis factor-alpha, and reduced hepatocyte apoptosis after GalN/LPS administration. In support of the role of JNK in promoting the mitochondria-mediated apoptosis pathway, SP600125 prevented cytochrome c release, caspase-9 and caspase-3 activity. Moreover, SP600125 downregulated the mRNA and protein expression of Bad in the early periods following GalN/LPS injection and prevented Bid cleavage in the late periods. These results confirm the role of JNK as a critical apoptotic mediator in GalN/LPS-induced FHF. SP600125 has the potential to protect FHF by downregulating Bad and inhibiting Bid cleavage.

Overexpressed Id-1 is associated with a high risk of hepatocellular carcinoma development in patients with cirrhosis without transcriptional repression of p16.

BACKGROUND: Inhibitor of differentiation/DNA binding protein 1 (Id-1) plays a pivotal role in the regulation of cell proliferation and carcinogenesis via inhibiting basic helix-loop-helix (HLH) transcription factors. Recently, Id-1 was found to repress p16 in tumorous tissue specimens including hepatocellular carcinoma (HCC), but its relevance in precancerous liver tissues is unknown. METHODS: Id-1 expression in the liver tissue specimens of 112 patients with cirrhosis without HCC was studied by immunohistochemical analysis. Correlations were investigated between Id-1 expression and clinicopathologic features, the status of p16, and the risk of HCC occurrence. RESULTS: A high expression of Id-1 was observed in 42 patients (38%). The level of Id-1 expression was not associated with clinical standard parameters or the status of p16 in cirrhotic tissue specimens. The cumulative incidence of HCC development was significantly higher in a group of patients with high Id-1 expression (P = 0.0008). Multivariate analysis revealed that increased Id-1 expression is an independent significant factor for the risk of HCC development in patients with cirrhosis (relative risk = 2.75, P = 0.003). CONCLUSIONS: The results of the current study suggested that increased expression of Id-1 may play an important role in the early step of hepatocarcinogenesis, and might serve as a useful marker for determining patients with cirrhosis with a high risk of HCC occurrence.