Tokuhiro Matsubara

Human Blood Dendritic Cell Antigen 3 (BDCA3)^+ Dendritic Cells Are a Potent Producer of Interferon-λ in Response to Hepatitis C Virus

The polymorphisms in the interleukin (IL)‐28B (interferon‐lambda [IFN]‐λ3) gene are strongly associated with the efficacy of hepatitis C virus (HCV) clearance. Dendritic cells (DCs) sense HCV and produce IFNs, thereby playing some cooperative roles with HCV‐infected hepatocytes in the induction of interferon‐stimulated genes (ISGs). Blood dendritic cell antigen 3 (BDCA3)+ DCs were discovered as a producer of IFN‐λ upon Toll‐like receptor 3 (TLR3) stimulation. We thus aimed to clarify the roles of BDCA3+ DCs in anti‐HCV innate immunity. Seventy healthy subjects and 20 patients with liver tumors were enrolled. BDCA3+ DCs, in comparison with plasmacytoid DCs and myeloid DCs, were stimulated with TLR agonists, cell‐cultured HCV (HCVcc), or Huh7.5.1 cells transfected with HCV/JFH‐1. BDCA3+ DCs were treated with anti‐CD81 antibody, inhibitors of endosome acidification, TIR‐domain‐containing adapter‐inducing interferon‐β (TRIF)‐specific inhibitor, or ultraviolet‐irradiated HCVcc. The amounts of IL‐29/IFN‐λ1, IL‐28A/IFN‐λ2, and IL‐28B were quantified by subtype‐specific enzyme‐linked immunosorbent assay (ELISA). The frequency of BDCA3+ DCs in peripheral blood mononuclear cell (PBMC) was extremely low but higher in the liver. BDCA3+ DCs recovered from PBMC or the liver released large amounts of IFN‐λs, when stimulated with HCVcc or HCV‐transfected Huh7.5.1. BDCA3+ DCs were able to induce ISGs in the coexisting JFH‐1‐positive Huh7.5.1 cells. The treatments of BDCA3+ DCs with anti‐CD81 antibody, cloroquine, or bafilomycin A1 reduced HCVcc‐induced IL‐28B release, whereas BDCA3+ DCs comparably produced IL‐28B upon replication‐defective HCVcc. The TRIF‐specific inhibitor reduced IL‐28B release from HCVcc‐stimulated BDCA3+ DCs. In response to HCVcc or JFH‐1‐Huh7.5.1, BDCA3+ DCs in healthy subjects with IL‐28B major (rs8099917, TT) released more IL‐28B than those with IL‐28B minor genotype (TG). Conclusion: Human BDCA3+ DCs, having a tendency to accumulate in the liver, recognize HCV in a CD81‐, endosome‐, and TRIF‐dependent manner and produce substantial amounts of IL‐28B/IFN‐λ3, the ability of which is superior in subjects with IL‐28B major genotype. (HEPATOLOGY 2013)

TIE2-expressing monocytes as a diagnostic marker for hepatocellular carcinoma correlates with angiogenesis.

Angiogenesis is a critical step in the development and progression of hepatocellular carcinoma (HCC). Myeloid lineage cells, such as macrophages and monocytes, have been reported to regulate angiogenesis in mouse tumor models. TIE2, a receptor of angiopoietins, conveys pro‐angiogenic signals and identifies a monocyte/macrophage subset with pro‐angiogenic activity. Here, we analyzed the occurrence and kinetics of TIE2‐expressing monocytes/macrophages (TEMs) in HCC patients. This study enrolled 168 HCV‐infected patients including 89 with HCC. We examined the frequency of TEMs, as defined as CD14+CD16+TIE2+ cells, in the peripheral blood and liver. The localization of TEMs in the liver was determined by immunofluorescence staining. Micro‐vessel density in the liver was measured by counting CD34+ vascular structures. We found that the frequency of circulating TEMs was significantly higher in HCC than non‐HCC patients, while being higher in the liver than in the blood. In patients who underwent local radio‐ablation or resection of HCC, the frequency of TEMs dynamically changed in the blood in parallel with HCC recurrence. Most TEMs were identified in the perivascular areas of tumor tissue. A significant positive correlation was observed between micro‐vessel density in HCC and frequency of TEMs in the blood or tumors, suggesting that TEMs are involved in HCC angiogenesis. Receiver operating characteristic analyses revealed the superiority of TEM frequency to AFP, PIVKA‐II and ANG‐2 serum levels as diagnostic marker for HCC. Conclusion: TEMs increase in patients with HCC and their frequency changes with the therapeutic response or recurrence. We thus suggest that TEM frequency can be used as a diagnostic marker for HCC, potentially reflecting angiogenesis in the liver. (HEPATOLOGY 2013)

Association of enhanced activity of indoleamine 2,3-dioxygenase in dendritic cells with the induction of regulatory T cells in chronic hepatitis C infection

BackgroundAltered functions of dendritic cells (DCs) and/or increases of regulatory T cells (Tregs) are involved in the pathogenesis of chronic hepatitis C virus (HCV) infection. A tryptophan-catabolizing enzyme, indoleamine 2,3-dioxygenase (IDO), is reported to be an inducer of immune tolerance. Our aim was to clarify whether or not IDO is activated in chronic hepatitis C patients and its role in immune responses.MethodsThis study enrolled 176 patients with chronic HCV infection and 37 healthy volunteers. Serum kynurenine concentration was evaluated by high-performance liquid chromatography, and its correlation with clinical parameters was examined. Monocyte-derived DCs were prepared from the subjects and subsequently stimulated with a combination of lipopolysaccharide and interferon-gamma to induce functional IDO (defined as IDO-DCs). The phenotypes, kynurenine or cytokine production, and T-cell responses with IDO-DCs were compared between the patients and healthy volunteers.ResultsThe serum kynurenine level in the patients was significantly higher than that in the healthy volunteers, and the level of serum kynurenine was positively correlated with the histological activity or fibrosis score. IDO activity in IDO-DCs from the patients was significantly higher than that in IDO-DCs from the volunteers. Furthermore, IDO-DCs from the patients induced more Tregs in vitro compared with those from the volunteers, and the frequency of induced Tregs by IDO-DCs was decreased with an IDO-specific inhibitor.ConclusionsSystemic IDO activity is enhanced in chronic hepatitis C patients in correlation with the degree of liver inflammation and fibrosis. In response to inflammatory stimuli, DCs from the patients tend to induce Tregs, with some of this action being dependent on IDO.

Comparative analyses of regulatory T cell subsets in patients with hepatocellular carcinoma: A crucial role of CD25−FOXP3− T cells

Regulatory T cells (Tregs) play pivotal role in cancer‐induced immunoediting. Increment of CD25high+FOXP3+ natural Tregs has been reported in patients with hepatocellular carcinoma (HCC); however, the involvement of other type of Tregs remain elusive. We aimed to clarify whether FOXP3− Tregs are increased and functionally suppressive or not in patients with HCC. We enrolled 184 hepatitis C‐infected patients with chronic liver diseases or HCC, 57 healthy subjects and 27 HCC patients with other etiology. Distinct Treg subsets were phenotypically identified by the expression of CD4, CD25, CD127 and forkhead/winged helix transcription factor (FOXP3). Their gene profiles, frequency and suppressor functions against T cell proliferation were compared among the subjects. To examine the molecules involving in Treg differentiation, we cultured naive CD4+ T cells in the presence of HCC cells and dendritic cells. We determined two types of CD4+CD127− T cells with comparable regulatory ability; one is CD25high+ cells expressing FOXP3 (CD25high+FOXP3+ Tregs) and the other is CD25− cells without FOXP3− expression (CD25−FOXP3− cells). The peripheral or intrahepatic frequency of CD25−FOXP3− Tregs in HCC patients is higher than those in other groups, of which significance is more than CD25high+FOXP3+ cells. Of importance, CD25−FOXP3− Tregs, but not CD25high+FOXP3+ cells, dynamically change in patients accompanied by the ablation or the recurrence of HCC. CD25−FOXP3− T cells with CD127−IL‐10+ phenotype are inducible in vitro from naive CD4+ T cells, in which programmed cell death 1 ligand 1, immunoglobulin‐like transcript 4 and human leukocyte antigen G are involved.. In conclusion, CD25−FOXP3− Tregs with suppressive capacity are increased in patients with HCC, suggesting their distinct roles from CD25+FOXP3+ Tregs.

Frequency of coexistent carcinoma in sessile serrated adenoma/polyps and traditional serrated adenomas removed by endoscopic resection.

Background and study aims: Sessile serrated adenoma/polyps (SSA/Ps) have a different potential than traditional adenomatous polyps for developing into malignant colorectal cancer. However, little is known about the coexistent cancer rate. Here, we evaluate the frequency of carcinoma in serrated polyps removed by endoscopic resection (ER). Patients and methods: This was a retrospective single-center cohort study of consecutive patients with colorectal polyps who underwent ER from March 2003 to October 2014. We determined the frequency of serrated polyps among all resected colorectal polyps and analyzed the clinicopathological findings as well as the frequency and characteristics of coexistent carcinoma in the serrated polyps resected by ER based on pathology reports. Results: A total of 21,048 polyps from 15,326 patients were identified, including 15,984 traditional adenomatous polyps (75.9 %), 621 SSA/Ps (3.0 %), 136 traditional serrated adenomas (TSAs) (0.6 %), 1,121 hyperplastic polyps (5.3 %), and 3,186 polyps of other types (15.1 %). The clinical and endoscopic findings of SSA/Ps revealed a male predominance (68.6 %), with 61.7 % of the polyps located in the proximal colon. Males accounted for 77.2 % of all patients with TSAs, and 77.2 % of these polyps were located in the distal colon. The mean sizes of the SSA/Ps and TSAs were 8.8 and 10.7 mm, respectively. Among the SSA/Ps, 8 (1.3 %) cases had coexistent carcinoma, and 1 (0.7 %) patient with TSA showed coexistent carcinoma. In the patients with SSA/Ps, female sex and a tumor size ≥ 10 mm were predictive factors for coexistent carcinoma. Conclusions: The frequency of SSA/Ps with carcinoma was lower than that for traditional adenoma. Female sex and tumor size ≥ 10 mm were significant predictive factors for coexistent carcinoma.

The combination of anti‑HBc and anti‑HBs levels is a useful predictor of the development of chemotherapy‑induced reactivation in lymphoma patients with resolved HBV infection

Fatal chemotherapy-induced hepatitis B virus reactivation (HBV-R) is a well-described serious complication observed in patients with lymphoma and resolved HBV infection. The aim of the present study was to determine the predictive factors of the development of chemotherapy-induced HBV-R. A total of 77 consecutive newly diagnosed patients with lymphoma and resolved HBV infection, who received chemotherapy from 2007 through 2015 were analysed retrospectively. Significant predictive factors associated with HBV-R were identified based on the data from these patients. Ten patients developed HBV-R during and following chemotherapy, and two of these 10 patients developed HBV-associated hepatitis flares. There was a significant negative correlation between anti-hepatitis B core (HBc) titres prior to chemotherapy and time to HBV-R (P=0.016, R=−0.732). Univariate and multivariate logistic regression analyses demonstrated that anti-HBc and anti-hepatitis B surface (HBs) titres at baseline were significant predictive factors for HBV-R. In addition, patients with high anti-HBc titres at baseline (above 10 S/CO) were significantly more likely to experience HBV-R than patients with low anti-HBc and high anti-HBs titres (above 28 mIU/ml), who did not experience complete reactivation (P<0.0001). Furthermore, patients with low anti-HBs titres were significantly more likely to experience HBV-R than those with high anti-HBs titres (P=0.031). All HBV-R episodes among the patients with high anti-HBc titres occurred within 3 months following the initiation of chemotherapy. The combination of anti-HBc and anti-HBs titres, as opposed to either titre alone, at baseline in patients with lymphoma may serve as a surrogate marker for the occurrence of HBV-R under the influence of chemotherapy.

Nivolumab Induces Sustained Liver Injury in a Patient with Malignant Melanoma: A Case Report

A 42-year-old man was diagnosed with cStage IIIb malignant melanoma and underwent resection. After interferon-beta therapy, 18-fluorodeoxyglucose-positron emission tomography/computed tomography (18F-FDG PET/CT) showed multiple lung metastases, and he received nivolumab (2 mg/kg) every 3 weeks, resulting in a total of 17 cycles. After treatment, 18F-FDG PET/CT showed a significant decrease in the size of the metastases, but he had a Grade 4 alanine aminotransferase (ALT) elevation. Liver histology revealed drug-induced liver damage. Therefore, we performed steroid half-pulse therapy followed by oral methylprednisolone, but his ALT level did not completely recover to the normal range even after five months. We herein report a case with specific, sustained liver injury induced by nivolumab as an immune-related adverse events.

Combination of two-hour post-endoscopic retrograde cholangiopancreatography amylase levels and cannulation times is useful for predicting post-endoscopic retrograde cholangiopancreatography pancreatitis

AIM To estimate the efficacy of 2 h post-endoscopic retrograde cholangiopancreatography (ERCP) serum amylase levels and other factors for predicting post-ERCP pancreatitis. METHODS This was a retrospective, single-center cohort study of consecutive patients who underwent ERCP from January 2010 to December 2013. Serum amylase levels were measured 2 h post-procedure, and patient- and procedure-related pancreatitis (PEP) risk factors were analyzed using a logistic model. RESULTS A total of 1520 cases (average age 72 ± 12 years, 60% male) were initially enrolled in this study, and 1403 cases (725 patients) were ultimately analyzed after the exclusion of 117 cases. Fifty-five of these cases developed PEP. We established a 2 h serum amylase cutoff level of two times the upper limit of normal for predicting PEP. Multivariate analysis revealed that a cannulation time of more than 13 min [odds ratio (OR) 2.28, 95%CI: 1.132-4.651, P = 0.0210] and 2 h amylase levels greater than the cutoff level (OR = 24.1, 95%CI: 11.56-57.13, P < 0.0001) were significant predictive factors for PEP. Forty-seven of the 55 patients who developed PEP exhibited 2 h amylase levels greater than the cutoff level (85%), and six of the remaining eight patients who developed PEP (75%) required longer cannulation times. Only 2 of the 1403 patients (0.14%) who developed PEP did not exhibit concerning 2 h amylase levels or require longer cannulation times. CONCLUSION These findings indicate that the combination of 2 h post-ERCP serum amylase levels and cannulation times represents a valuable marker for identifying patients at high risk for PEP.

Clinically diagnosed late-onset fulminant Wilson’s disease without cirrhosis: A case report

A 64-year-old woman was referred to our hospital with jaundice of the bulbar conjunctiva and general fatigue. After admission, she developed hepatic encephalopathy and was diagnosed with fulminant hepatitis based on the American Association for the Study of Liver Disease (AASLD) position paper. Afterwards, additional laboratory findings revealed that serum ceruloplasmin levels were reduced, urinary copper levels were greatly elevated and Wilson’s disease (WD)-specific routine tests were positive, but the Kayser-Fleischer ring was not clear. Based on the AASLD practice guidelines for the diagnosis and treatment of WD, the patient was ultimately diagnosed with fulminant WD. Then, administration of penicillamine and zinc acetate was initiated; however, the patient unfortunately died from acute pneumonia on the 28th day of hospitalization. At autopsy, the liver did not show a bridging pattern of fibrosis suggestive of chronic liver injury. Here, we present the case of a patient with clinically diagnosed late-onset fulminant WD without cirrhosis, who had positive disease-specific routine tests.

Number of polyps detected is a useful indicator of quality of clinical colonoscopy

Background and study aims  Adenoma detection rate (ADR) is a well-known quality indicator (QI) for colonoscopy. It is, however, difficult to evaluate ADR during practice. The aim of this study was to investigate the number of endoscopically detected polyps as a QI for colonoscopy. Patients and methods  This was a retrospective single-center cohort study of 5,190 consecutive patients who underwent colonoscopy from January 2015 to May 2016. Among these patients, we ultimately enrolled 1,937 patients for initial colonoscopy. We evaluated QIs including bowel preparation, cecum intubation time, withdrawal time, number of endoscopically detected polyps, ADR and advanced neoplasia detection rate (ANDR) Results  The mean number of endoscopically detected polyps, ADR and ANDR were 1.5 ± 2.3 (95 % confidence interval (CI)1.4 – 1.6), 38.6 % (95 % CI 36.5-40.8), and 18.3 % (95 % CI 16.6 – 20.1), respectively. ADR and ANDR increased with the number of endoscopically detected polyps, but the correlation reached a plateau at five or more polyps. We divided the patients into three groups based on the number of polyps (1 to 2, 3 to 4, and 5 or more). Logistic regression analysis adjusted by age and sex revealed that presence of a large number of polyps was a strong predictor of advanced neoplasia (odds ratio: 3.1 [95 % CI 2.2 – 4.3] for 3 to 4 polyps and 7.9 [95 % CI 5.4 – 11.8] for 5 or more polyps when using the presence of 1 or 2 polyps as a reference). Conclusion  The number of endoscopically detected polyps can predict risk of advanced neoplasia and may thus be a new QI for colonoscopy.