Satoshi Egawa

IgG Oligosaccharide Alterations Are a Novel Diagnostic Marker for Disease Activity and the Clinical Course of Inflammatory Bowel Disease

BACKGROUND AND AIMS:Patients with inflammatory bowel disease (IBD) share several immunologic similarities with rheumatoid arthritis (RA). Patients with RA have significantly increased levels of serum agalactosyl immunoglobulin G (IgG). Our aim was to investigate the clinical significance of analyzing the oligosaccharide structure of serum IgG in patients with IBD.METHODS:Serum IgG oligosaccharide structures were analyzed using high-performance liquid chromatography in 60 patients with Crohns disease (CD), 58 patients with ulcerative colitis (UC), 27 healthy volunteers (HV), and 15 disease controls (DC). The activity and mRNA level of beta-1,4-galactosyltransferase (Beta4GalT) in antibody-secreting cells were investigated in these subjects.RESULTS:The agalactosyl fraction of the fucosylated IgG oligosaccharides (G0F/G2F) in CD and UC was significantly greater than that in HV and DC (P < 0.001). The percentage of subjects with a high G0F/G2F in CD, UC, HV, and DC was 72%, 33%, 0%, and 0%, respectively. G0F/G2F, which is significantly correlated with disease severity in both CD and UC, had higher sensitivity to diagnose IBD compared with anti-Saccharomyces cerevisiae antibody. Moreover, G0F/G2F was significantly correlated with the prognosis of UC patients: patients with a high G0F/G2F did not maintain long-term remission. The activity and mRNA level of Beta4GalT were significantly elevated in UC but not in CD.CONCLUSIONS:G0F/G2F is a potentially effective diagnostic marker of disease activity in both CD and UC, and of the clinical course in UC. A pathophysiologic difference between CD and UC was also demonstrated.

Synergistic antitumor effects of celecoxib with 5-fluorouracil depend on IFN-γ

Cyclooxygenase‐2 (COX‐2) inhibitors are effective chemopreventive agents against colorectal cancers. For treatment of advanced cancers, combination of COX‐2 inhibitors and chemotherapy has been attempted, but the results are still controversial. In the present study, the effects of the COX‐2 inhibitor celecoxib on the anticancer potential of chemotherapy, and its mechanisms of action were investigated in point of the angiogenesis, using an advanced cancer model in mice. BALB/c mice were inoculated with colon 26 cells. After the allograft grew up to 5 mm in diameter, the animals received celecoxib, 5FU, or a combination of 5FU and celecoxib (5FU/celecoxib). After 21‐days of the treatment, 5FU/celecoxib significantly inhibited the tumor growth and the tumor vessel density compared with the other groups. Celecoxib, 5FU or 5FU/celecoxib significantly suppressed the VEGF content in tumor tissues. 5FU/celecoxib also enhanced IFN‐γ levels in tumor tissue, which could be involved in the potent antitumor effects of 5FU/celecoxib. This hypothesis was proven, because in IFN‐γ knockout (IFN‐γ−/−) mice, the inhibitory effects of 5FU/celecoxib on angiogenesis and tumor growth were significantly impaired compared with that in wild type mice. These results suggest that celecoxib enhances the antitumor effect of 5FU against an advanced colon cancer model by suppressing angiogenesis. In addition to VEGF, IFN‐γ has pivotal roles in tumor suppression induced by celecoxib.

Comparative study of esomeprazole and lansoprazole in triple therapy for eradication of Helicobacter pylori in Japan

AIM To evaluate the efficacy and safety of esomeprazole-based triple therapy compared with lansoprazole therapy as first-line eradication therapy for patients with Helicobacter pylori (H. pylori) in usual post-marketing use in Japan, where the clarithromycin (CAM) resistance rate is 30%. METHODS For this multicenter, randomized, open-label, non-inferiority trial, we recruited patients (≥ 20 years of age) with H. pylori infection from 20 hospitals in Japan. We randomly allocated patients to esomeprazole therapy (esomeprazole 20 mg, CAM 400 mg, amoxicillin (AC) 750 mg for the first 7 d, with all drugs given twice daily) or lansoprazole therapy (lansoprazole 30 mg, CAM 400 mg, AC 750 mg for the first 7 d, with all drugs given twice daily) using a minimization method with age, sex, and institution as adjustment factors. Our primary outcome was the eradication rate by intention-to-treat (ITT) and per-protocol (PP) analyses. H. pylori eradication was confirmed by a urea breath test from 4 to 8 wk after cessation of therapy. RESULTS ITT analysis revealed the eradication rates of 69.4% (95%CI: 61.2%-76.6%) for esomeprazole therapy and 73.9% (95%CI: 65.9%-80.6%) for lansoprazole therapy (P = 0.4982). PP analysis showed eradication rate of 76.9% (95%CI: 68.6%-83.5%) for esomeprazole therapy and 79.8% (95%CI: 71.9%-86.0%) for lansoprazole therapy (P = 0.6423). There were no differences in adverse effects between the two therapies. CONCLUSION Esomeprazole showed non-inferiority and safety in a 7 day-triple therapy for eradication of H. pylori compared with lansoprazole.

Altered Oligosaccharide Structures Reduce Colitis Induction in Mice Defective in β-1,4-Galactosyltransferase

BACKGROUND & AIMS Oligosaccharide modifications induce various functional changes in immune cells. The galactose-deficient fraction of fucosylated IgG oligosaccharides is increased, whereas that of β-1,4-galactosyltransferase I (B4GalTI) is reduced, in patients with Crohns disease. We investigated the role of oligosaccharide modification in the pathophysiology of colitis using B4galt1-deficient mice. METHODS Colitis severity was compared between B4galt1(+/-) and B4galt1(+/+) mice. B cells isolated from B4galt1(+/-) and B4galt1(+/+) mice were adoptively transferred to recombination activating gene 2(-/-) mice, in which colitis was induced by administration of CD4(+)CD62L(+) T cells. Cell-surface glycan profiles were determined by lectin microarray analysis. Cytokine production was determined in a coculture of various types of cells isolated from either B4galt1(+/-) or B4galt1(+/+) mice. RESULTS Colitis induction by dextran sodium sulfate or trinitrobenzene sulfonic acid was significantly reduced in B4galt1(+/-) mice, which had galactose deficiency in IgG oligosaccharides (similar to patients with Crohns disease) compared with B4galt1(+/+) mice. Amelioration of colitis was associated with increased production of interleukin-10 by macrophages in B4galt1(+/-) mice. Colitis induction in recombination activating gene 2(-/-) mice by administration of CD4(+)CD62L(+) T cells was reduced by cotransfer of B cells isolated from B4galt1(+/-), but not from B4galt1(+/+) mice. Lectin microarray analysis revealed increased expression of polylactosamines on B4galt1(+/-) B cells and macrophages, compared with B4galt1(+/+) cells. The production of interleukin-10 from macrophages was induced via their direct interaction with B4galt1(+/-) B cells. CONCLUSIONS Altered oligosaccharide structures on immune cells modulate mucosal inflammation. Oligosaccharides in immune cells might be a therapeutic target for inflammatory bowel diseases.

Juvenile hepatocellular carcinoma with congestive liver cirrhosis

A case of juvenile hepatocellular carcinoma (HCC) with congestive liver cirrhosis is reported. The patient was a 21-year-old woman. She had been diagnosed as having transposition of the great arteries, type 2, in 1978. She underwent the Mustard operation, but suffered from chronic heart failure. In 1995, she experienced abdominal pain and underwent examination. The laboratory data were normal, except for elevated total bilirubin (5.2 mg/dl). Blood examinations were performed at frequent intervals, and the total bilirubin level fluctuated between 0.9 and 8.1 mg/dl over the next 4 years, but the transaminase level remained normal. In 1999, she experienced abdominal pain again and was admitted to our hospital. Computed tomography showed four space-occupying lesions in the liver; 45 mm, 20 mm, 12 mm, and 10 mm in size. She was diagnosed as having HCC, and transcatheter arterial chemoembolization and percutaneous ethanol injection therapy were performed. Histology of the cancerous and the noncancerous liver tissue revealed HCC, moderately differentiated type, in cirrhotic liver with congestion. This patient had no background factors of liver disease, except for liver congestion, associated with the chronic heart failure. Because most patients with cardiac cirrhosis die of cardiac disease, only a small number of these patients develop liver failure. However, the incidence of HCC in patients with congestive liver disease is likely to increase in the future, as survival time is prolonged with the advances in treatment for chronic heart failure. Therefore, patients with congestive liver disease should be followed, taking into account the possibility of HCC.

Functional analysis of agalactosyl IgG in inflammatory bowel disease patients

Background: Agalactosyl immunoglobulin (Ig) G is increased in inflammatory bowel disease (IBD) similarly to rheumatoid arthritis (RA). The lectin complement pathway is shown to be activated through association of agalactosyl IgG with mannan‐binding lectin (MBL) in RA. Functional changes of IgG agalactosylation in IBD, however, have not yet been clarified. Methods: The ratio of the agalactosyl/non‐agalactosyl fraction in fucosylated IgG oligosaccharides (G0F/G2F) and serum MBL levels were analyzed in 59 patients with Crohns disease (CD), 64 ulcerative colitis (UC), and 39 healthy volunteers (HV). The MBL levels associated with serum IgG were analyzed by enzyme‐linked immunosorbent assay. MBL expression in the intestinal mucosa was analyzed by immunohistochemistry. Phagocytosis of sheep red blood cells (SRBC) reacted with either an agalactosyl or non‐agalactosyl SRBC‐specific IgG antibody was determined by flow cytometry. Results: The serum MBL levels were not significantly different among CD, UC, or HV. In patients with CD, the serum MBL levels were negatively correlated with the Crohns Disease Activity Index (CDAI). The levels of MBL associated with agalactosyl IgG were not different from those associated with non‐agalactosyl IgG. Immunoreactivity to MBL was less in the inflamed mucosa compared with the noninflamed mucosa. Phagocytic activity of SRBC was significantly higher in the presence of agalactosyl IgG compared to non‐agalactosyl IgG. Conclusions: Agalactosyl IgG oligosaccharides enhanced antibody‐dependent phagocytosis in vitro but did not activate the lectin complement pathway. Oligosaccharide alterations of IgG are not only a marker of IBD but also functionally modulate the immune function of IBD. (Inflamm Bowel Dis 2010;)

Cultured bone marrow cell local implantation accelerates healing of ulcers in mice

BackgroundThe therapeutic potential of bone marrow (BM)-derived cells in ulcers is not known. This study aimed to clarify (1) cell types that are derived from the BM which infiltrate ulcers; (2) whether BM-derived cells or gastric myofibroblasts can be used for cell transplantation to treat ulcers; and (3) the phenotypes of such transplantable cells.Methods(1) Wild-type mice were transplanted with BM cells of green fluorescent protein (GFP)-transgenic mice. Acetic acid-induced gastric ulcers were produced in mice after BM transplantation. (2) BM cells and gastric myofibroblasts were isolated from GFP-transgenic mice. Bone marrow cells attached to plastic dishes were selected for expansion. Gastric ulcers were induced, and BM-derived cells, myofibroblasts, or phosphate-buffered saline were injected around ulcers. The ulcer healing process was examined macroscopically and histologically. (3) Expression of growth factors and cytokines in transplantable cells was examined by reverse transcriptase-polymerase chain reaction.Results(1) GFP-positive cells with interstitial phenotypes were observed at the ulcerated area. (2) Ulcer healing was significantly promoted by the injection of BM-derived cells compared to controls on day 7, but not on day 3. The BM-derived cells were observed in the tissue surrounding the ulcer. However, myofibroblasts were not found. (3) The BM-derived cells expressed hepatocyte growth factor, transforming growth factor-β1, and other stromal factors before transplantation, and had mesenchymal phenotypes after transplantation.ConclusionsBM-derived cells are involved in the ulcer healing. BM-derived cells, but not myofibroblasts, are locally implantable to ulcers. Thus, BM-derived cells can be transplanted to accelerate ulcer healing.

Upregulation of GRAIL is associated with remission of ulcerative colitis

Abrogating tolerance against unidentified antigens is a critical step in the pathogenesis of ulcerative colitis (UC). T cell anergy, one of the main mechanisms of tolerance, has been shown to be induced by E3 ubiquitin ligases, such as gene related to anergy in lymphocytes (GRAIL), Itch, and c-Cbl in mice. However, it is not well known whether these E3 ligases play roles in human diseases. The pathophysiological role of the E3 ligases in patients with UC was investigated. At first, the expression of GRAIL, Itch, and c-Cbl in human anergic T cells was analyzed by quantitative RT-PCR and Western immunoblotting. Next, the mRNA expression of the E3 ligases was analyzed in peripheral CD4+ T cells of 20 patients with UC and 10 healthy volunteers (HV). mRNA expression was analyzed in patients with active UC before and after treatment with prednisolone and leukocytapheresis. Anergic human CD4+ T cells expressed significantly higher levels of GRAIL, Itch, and c-Cbl than nonanergic cells. GRAIL expression was significantly higher in patients with UC in remission than in patients with active disease and in HV (P < 0.01). The level of GRAIL expression was also significantly increased in patients with active disease whose clinical activity index scores improved after treatment (P < 0.05). There were no significant differences in Itch and c-Cbl expression among patients with active UC, patients with UC in remission, and HV. These data suggest that GRAIL plays an important role in maintaining remission in patients with UC.

Regulation of anergy-related ubiquitin E3 ligase, GRAIL, in murine models of colitis and patients with Crohn’s disease

BackgroundAbrogating tolerance is a critical step in the pathogenesis of Crohn’s disease (CD). T cell-anergy is one of the main mechanisms of tolerance and is regulated by the gene related to anergy in lymphocytes (GRAIL). This study investigated the expressions and regulation of GRAIL in CD and murine colitis models.MethodsExpressions of GRAIL mRNA and protein in CD4+ T cells were investigated in the peripheral blood and mucosal tissues of patients with CD, mice with dextran sodium salt (DSS)-induced colitis, and Il-10-deficient mice. MicroRNAs responsible for the regulation of GRAIL were examined by miRNA microarray. GRAIL-overexpressing T cells were intravenously injected in mice with DSS-induced colitis.ResultsThe GRAIL expression was higher in the lamina propria (LP) CD4+ T cells of CD patients than of the control subjects, while it was lower in the peripheral blood CD4+ T cells of the CD patients than of the control subjects. The GRAIL mRNA expression was lower, but the GRAIL protein expression was higher in the LP of colitic mice than that of non-colitic mice. The miRNA microarray identified miR-290-5p as an miRNA that inhibits expression of the GRAIL protein and that is highly expressed in the LP of non-colitic mice. GRAIL-expressing T cells expressed regulatory T cell markers and showed suppressive effects in murine DSS-induced colitis.ConclusionsOur results show that expression of GRAIL is uniquely regulated by the specific miRNA in the intestinal mucosa, and suggest that GRAIL may associate with the pathophysiology of CD.

Renal dysfunction is an independent risk factor for bleeding after gastric ESD

Background and study aims: The number of patients with chronic kidney disease (CKD) is increasing worldwide and gastric cancer sometimes occurs with CKD. However, the safety and feasibility of endoscopic submucosal dissection (ESD) for patients with CKD are not clear. The aim of this study is to clarify the feasibility and safety of gastric ESD for patients with CKD. Patients and methods: This was a multicenter retrospective cohort study. In total, 144 patients with CKD who underwent gastric ESD between May 2003 and October 2012 were enrolled. The patients were divided into three groups: stage 3 (estimated glomerular filtration rate [eGFR]: 30 – 59 mL/min), stage 4 (eGFR: 15 – 29 mL/min), and stage 5 (eGFR: < 15 mL/min) according to the Kidney Disease Improving Global Outcomes Guidelines. The en bloc and curative resection rates and complications were assessed as short-term outcomes. Overall survival was analyzed using Kaplan – Meier methods. Results: In total, 92 patients were in stage 3 CKD; 23 in stage 4; and 29 in stage 5, including 19 patients in hemodialysis. The en bloc resection rate was 95.8 %. Post-ESD bleeding was observed in four patients with stage 5 CKD (13.8 %), three with stage 4 (13.0 %), and one with stage 3 (1.1 %). All bleeding could be controlled by endoscopic hemostasis, but five patients required blood transfusion. Perforation occurred in two patients (6.9 %) with stage 5 CKD, none (0 %) with stage 4, and two (4.3 %) with stage 3. Multivariate Poisson regression analysis revealed CKD stage 4 was a critical factor related to bleeding, whereas diabetes mellitus and CKD stage 5, which largely consist of patients receiving hemodialysis, were not. The median observation period of patients who achieved curative resection was 25.9 months (range 0.8—112.7 months) and the 3-year overall survival rate was 92.5 %. Conclusions: Estimated GFR is a significant independent predictive factor of post-ESD bleeding in patients with CKD.