Eriko Okada

Mucosal T Cells Expressing High Levels of IL-7 Receptor Are Potential Targets for Treatment of Chronic Colitis

The IL-7/IL-7R-dependent signaling pathway plays a crucial role in regulating the immune response in intestinal mucosa. Here we demonstrate the pivotal role of this pathway in the development and treatment of chronic colitis. T cells expressing high levels of IL-7R were substantially infiltrated in the chronic inflamed mucosa of TCR α-chain knockout mice and IL-7 transgenic mice. Transfer of mucosal T cells expressing high levels of IL-7R, but not T cells expressing low levels of IL-7R, from these mice into recombinase-activating gene-2−/− mice induced chronic colitis. Selective elimination of T cells expressing high levels of IL-7R by administrating small amounts of toxin-conjugated anti-IL-7R Ab completely ameliorated established, ongoing colitis. These findings provide evidence that therapeutic approaches targeting mucosal T cells expressing high levels of IL-7R are effective in the treatment of chronic intestinal inflammation and may be feasible for use in the therapy of human inflammatory bowel disease.

Magnetic resonance enterocolonography is useful for simultaneous evaluation of small and large intestinal lesions in Crohn's disease

Background: We developed novel magnetic resonance enterocolonography (MREC) for simultaneously evaluating both small and large bowel lesions in patients with Crohns disease (CD). The aim of this study was to evaluate the diagnostic performance of MREC by comparing results of this procedure to those of endoscopies for evaluating the small and large bowel lesions of patients with CD. Methods: Thirty patients with established CD were prospectively examined by newly developed MREC. Patients underwent ileocolonoscopy (ICS) (24 procedures) or double‐balloon endoscopy (DBE) (10 procedures) after MREC on the same day. Two gastroenterologists and two radiologists who were blinded to the results of another study evaluated endoscopy and MREC findings, respectively. Results: In colonic lesions the sensitivities of the MREC for deep mucosal lesions (DML), all CD lesions, and stenosis were 88.2, 61.8, and 71.4%, respectively, while the specificities were 98.1, 95.3, and 97.7%, respectively. In small intestinal lesions, MREC sensitivities for DML, all CD lesions, and stenosis were 100, 85.7, and 100%, respectively, while specificities were 100, 90.5, and 93.1%, respectively. Endoscopic scores were significantly correlated with MREC scores. Eleven (46%) of the 24 patients who were clinically not suspected to show stricture were observed to demonstrate stricture by radiologists. Conclusions: Our results demonstrated that MREC can simultaneously detect the CD lesions of the small and large intestine. MREC can be performed without radiation exposure, the use of enema, or the placement of a naso‐jejunal catheter. MREC and endoscopy have comparable abilities for evaluating mucosal lesions of patients with CD. (Inflamm Bowel Dis 2010;)

Single-operator double-balloon endoscopy (DBE) is as effective as dual-operator DBE.

Background and Study Aims:  Double‐balloon endoscopy (DBE) is a new device that allows diagnosis and treatment throughout the entire small intestine. Although the originally described method requires two operators, we have recently developed a method to perform DBE by a single operator. We here assessed the clinical usefulness of this one‐person method in comparison to the conventional two‐person DBE.

Lineage-Specific Expression of Bestrophin-2 and Bestrophin-4 in Human Intestinal Epithelial Cells

Intestinal epithelial cells (IECs) regulate the absorption and secretion of anions, such as HCO3- or Cl-. Bestrophin genes represent a newly identified group of calcium-activated Cl- channels (CaCCs). Studies have suggested that, among the four human bestrophin-family genes, bestrophin-2 (BEST2) and bestrophin-4 (BEST4) might be expressed within the intestinal tissue. Consistently, a study showed that BEST2 is expressed by human colonic goblet cells. However, their precise expression pattern along the gastrointestinal tract, or the lineage specificity of the cells expressing these genes, remains largely unknown. Here, we show that BEST2 and BEST4 are expressed in vivo, each in a distinct, lineage-specific manner, in human IECs. While BEST2 was expressed exclusively in colonic goblet cells, BEST4 was expressed in the absorptive cells of both the small intestine and the colon. In addition, we found that BEST2 expression is significantly down-regulated in the active lesions of ulcerative colitis, where goblet cells were depleted, suggesting that BEST2 expression is restricted to goblet cells under both normal and pathologic conditions. Consistently, the induction of goblet cell differentiation by a Notch inhibitor, LY411575, significantly up-regulated the expression of not BEST4 but BEST2 in MUC2-positive HT-29 cells. Conversely, the induction of absorptive cell differentiation up-regulated the expression of BEST4 in villin-positive Caco-2 cells. In addition, we found that the up- or down-regulation of Notch activity leads to the preferential expression of either BEST4 or BEST2, respectively, in LS174T cells. These results collectively confirmed that BEST2 and BEST4 could be added to the lineage-specific genes of humans IECs due to their abilities to clearly identify goblet cells of colonic origin and a distinct subset of absorptive cells, respectively.

Reduced Human α-defensin 6 in Noninflamed Jejunal Tissue of Patients with Crohn’s Disease:

Background:Mucosal barrier dysfunction is considered a critical component of Crohn’s disease (CD) pathogenesis after the identification of susceptibility genes. However, the precise mechanism underlying mucosal barrier dysfunction has not yet been elucidated. We therefore aimed to elucidate the molecular mechanism underlying the expression of human &agr;-defensin 6 (HD6) in patients with CD. Methods:HD6 expression was induced by the transfection of an atonal homolog 1 (Atoh1) transgene and was assessed by reverse transcription polymerase chain reaction. The HD6 promoter region targeted by Atoh1 and &bgr;-catenin was determined by reporter analysis and chromatin immunoprecipitation assay. HD5/HD6/Atoh1/&bgr;-catenin expression in noninflamed jejunal samples collected by balloon endoscopy from 15 patients with CD and 9 non-inflammatory bowel disease patients were assessed by immunofluorescence. Results:Both promoter activity and gene expression of HD6 was significantly upregulated by the Atoh1 transgene in human colonic cancer cell line. We identified a TCF4 binding site and an E-box site, critical for the regulation of HD6 transcriptional activity by directly binding of Atoh1 in the 200-bp HD6 promoter region. The treatment with &bgr;-catenin inhibitor also decreases HD6 promoter activity and gene expression. Moreover, HD6 expression, but not HD5 expression, was found to be decreased in noninflamed jejunal regions from patients with CD. In HD6-negative crypts, nuclear accumulation of &bgr;-catenin was impaired. Conclusions:HD6 expression was found to be regulated by cooperation between Atoh1 and &bgr;-catenin within the HD6 promoter region. Downregulation of HD6 in noninflamed mucosa may contribute to mucosal barrier dysfunction of patients with CD.

Modified single‐operator method for double‐balloon endoscopy

Applications of double‐balloon endoscopy (DBE) have expanded widely to areas beyond small‐intestine endoscopy. Two endoscopists are required for standard insertion, but it is preferable to have DBE carried out by one endoscopist to optimize control of the procedure and because of human resources issues. We previously reported on the Single‐Operator Method, but here we describe newly modified insertion techniques that facilitate and enhance the performance of DBE by a single endoscopist. Our new technique consists of Hooking Technique, Outside Support, Grasp Scope and Overtube, Continuous Overtube Infusion and Double‐Overtube Method. These new techniques make it easier to carry out the Single‐Operator Method.

Wait Time for Hip Fracture Surgery and Mortality

Author Contributions: Ms Walter had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis. Concept and design: Loeb, Makarov, Lepor, Walter. Acquisition, analysis, or interpretation of data: Loeb, Byrne, Makarov, Walter. Drafting of the manuscript: Loeb. Critical revision of the manuscript for important intellectual content: All authors. Statistical analysis: Walter. Obtained funding: Loeb, Makarov. Administrative, technical, or material support: Byrne, Lepor. Supervision: Loeb, Lepor.

Mo1833 Human Alpha-Defensin 6 Regulated by the Cooperation of Beta-Catenin and ATOH1, Might Be the Pathogenesis of Crohn's Disease

Recommended therapy of bacterial infection is generally based on in vitro susceptibility of an organism to an infecting organism. Yet drug bioavailability based on solubility, protein binding and other factors along with host resistance and inflammatory-immune response importantly alter response to treatment. The objective of the study was to establish in vivo animal model to study antimicrobial therapy of C. difficile infection. C. difficile isolate with hyper-virulent factors (toxin A/B plus binary toxin and 18 base pair deletion in tcdC gene) was used in the study. The cultured C. difficile was stained with near infrared (NIR) dye. Stained C. difficilewere determined by using fluorescent microscope and confocal microscope. To monitor stained bacterial trafficking in the gut animals were imaged in real-time. The intestines from treated animals were dissected at the end of imaging study. The bacterial signal intensity and migration pattern were recorded and compared. C. difficile toxin secretion in the different segment of GI system was analyzed. Results showed the C. difficile can be stained by NIR dye. Stained bacteria can be imaged by NIR camera system to track the C. difficile traffic in the gut in real-time. Untreated control animal has different bacteria migration pattern than the animal with C. difficile infection treated with ciprofloxacin. TheNIR florescent probe can be used to visualize C. difficile trafficking in the gastrointentinal tract through culturing, staining and imaging. Fig. 1. Confocal images of C. difficile. Viable bacterial stained with NIR dye (A. Red) and dead bacterial determined with Sytox green (B. Green). Stain efficiency was determined by co-localized all cells (C. Green) and NIR (C. Red). Confocal microscope analyzed NIR dye binding at subcellular level (D). Red and green represent NIR and cell nuclei, respectively. Results demonstrate C. difficile can be stained by NIR dye. Most bacteria remain viable after the staining procedure.

Histological diagnosis of follicular lymphoma by biopsy of small intestinal normal mucosa

Due to advances in double‐balloon endoscopy, various types of malignant lymphoma of the small intestine have been observed at very early stages. We report here that after remission of diffuse large B‐cell lymphoma, follicular lymphoma recurred in the mucosa of the small intestine. Furthermore, these lesions were diagnosed by biopsy from normal mucosa as diminutive erosions and reddish looking. If a small intestinal lesion is suspected of being a malignant lymphoma, a double‐balloon endoscopy should be carried out, and a biopsy should be taken and inspected.

Endoscopic ultrasound with double-balloon endoscopy for the diagnosis of inverted Meckel’s diverticulum: a case report

IntroductionInverted Meckel’s diverticulum has usually been misdiagnosed in the cases based on computed tomography images presented in the literature. The final diagnosis was made intra-operatively or by pathology reports after surgery. Despite this, preoperative diagnosis could be made successfully by using endoscopic ultrasound with double-balloon endoscopy prior to surgery.Case presentationA 60-year-old Japanese woman with severe anemia complained of several episodes of black stool over the preceding 2 years. Abdominal computed tomography showed a 3.0-cm low-density tumor in the ileum, suggesting a diagnosis of intestinal lipoma. Examination of the tumor by endoscopic ultrasound with double-balloon endoscopy revealed a hypo-echoic layer corresponding to the muscularis propria, and a hyper-echoic layer corresponding to the fat tissue. These findings, which suggested that the tumor included areas outside the intestinal serosa, are not typical for a lipoma, despite the existence of a hyper-echoic layer corresponding to fatty tissue. We then considered a diagnosis of inverted Meckel’s diverticulum.ConclusionLipoma and inverted Meckel’s diverticulum are difficult to differentially diagnose by computed tomography. Polypectomy is the preferred therapeutic approach when a lipoma is present; however, polypectomy in a patient with Meckel’s diverticulum requires full-thickness resection. Situations where polypectomy is performed without preparing for full-thickness resection can be avoided by first making a precise diagnosis using double-balloon endoscopy and endoscopic ultrasound.