Kotaro Kuwaki

Interleukin-10 in the Pathophysiology of Inflammatory Bowel Disease: Increased Serum Concentrations During the Recovery Phase

Using a specific enzyme-linked immunosorbent assay, IL-10 concentrations were measured in serum from 62 patients with ulcerative colitis (UC), 43 with Crohns disease (CD), 25 with other colitides, and 44 normal control subjects. Serum IL-10 concentrations were increased in patients with active UC but not in those with active CD when compared with normal control subjects. A time course study showed that in patients with UC and CD, serum concentrations of IL-6 and C-reactive protein increased during the acute phase and returned to normal as patients go into remission. Notably, serum IL-10 concentrations increased during the phase of disease resolution and declined thereafter regardless of the treatment modality. Gel filtration analysis indicated that IL-10 circulated predominantly as a dimer. In conclusion, this study shows that serum IL-10 is increased during disease recovery in patients with inflammatory bowel disease, and may be a helpful marker in monitoring disease status.

Clinical trial: comparison of alendronate and alfacalcidol in glucocorticoid‐associated osteoporosis in patients with ulcerative colitis

Background  Bone loss is often observed in patients with ulcerative colitis, particularly if they require glucocorticoids.

Mobilization of bone marrow cells by leukocytapheresis in patients with ulcerative colitis.

Abstract:  While several trials have suggested that leukocytapheresis by filtration can benefit patients with active ulcerative colitis (UC), mechanisms underlying these benefits are largely unknown. We studied how leukocytapheresis mobilizes bone marrow cells into the peripheral circulation in patients with active UC. Leukocytapheresis transiently reduced peripheral leukocytes, followed by an overshoot increase with emergence of immature leukocytes. The numbers of colonies and CD34+ cells were comparable between UC patients and normal controls. Shortly after leukocytapheresis, the numbers of both colonies and CD34+ cells increased significantly in UC patients (P < 0.0001 and P = 0.0372, respectively). This was not associated with changes in the concentration of circulating cytokines or epinephrine. These results indicate that leukocytapheresis mobilizes bone marrow cells into the circulation. This cell replacement may partly explain the therapeutic benefit in UC. The functional role of the mobilized bone marrow cells in affected intestine remains to be characterized.

Recent understanding of leukocytapheresis (LCAP) for the treatment of inflammatory bowel disease.

Inflammatory bowel disease (IBD) is frequently associated with the infiltration of a large number of leukocytes into the bowel mucosa. Therefore, the removal of circulating leukocytes may be an attractive approach for the treatment of IBD. Leukocytapheresis with Cellsorba, a column of polyethylenephtarate fibers that captures monocytes, granulocytes, and lymphocytes, has been used to treat IBD, particularly ulcerative colitis, in Japan. The objective of this paper is to provide an overview of current knowledge regarding the mechanisms of action, available clinical data, and possible future perspectives for the use of LCAP with Cellsorba in the management of IBD. Leukocytapheresis appears to remove or inactivate inflammatory cells, to reset immunity by modulating immune system components like cytokines, and to repair the intestinal mucosa by mobilizing mesenchymal progenitors. Although the majority of clinical studies had an open-label design and enrolled only a small number of patients, leukocytapheresis has been demonstrated to exert clinical efficacy with an excellent safety profile. Although leukocytapheresis with Cellsorba appears very promising, its future in the treatment of IBD requires further evaluation.

Antibody markers in the diagnosis of inflammatory bowel disease

Inflammatory bowel disease (IBD), including Crohns disease and ulcerative colitis, is a chronic intestinal inflammation of unknown etiology. The diagnosis of IBD is based on endoscopic, radiologic and histopathologic criteria. Recently, the search for a noninvasive marker that could augment or replace part of this diagnostic process has become a focus of IBD research. In this review, antibody markers, including microbial antibodies, autoantibodies and peptide antibodies, will be described, focusing on their common features. At present, no single marker with qualities that are satisfactory for the diagnosis and treatment of IBD has been identified, although panels of some antibodies are being evaluated with keen interest. The discovery of novel IBD-specific and sensitive markers is anticipated. Such markers could minimize the use of endoscopic and radiologic examinations and could enable clinicians to implement individualized treatment plans designed to improve the long-term prognosis of patients with IBD.

DIRECT CHOLANGIOSCOPY USING A DOUBLE‐BALLOON ENTEROSCOPE: CHOLEDOCHOJEJUNOSTOMY WITH INTRADUCTAL BILIARY CARCINOMA

A 75‐year‐old man who underwent choledochojejunostomy for gallstones 30 years ago was hospitalized for general malaise. Abdominal computed tomography revealed marked dilation of the intrahepatic bile duct in the right lobe and an image of a hypervascular tumor. Endoscopic retrograde cholangiography using double‐balloon enteroscopy (DBE) showed a filling defect that was localized to the right hepatic bile duct. Furthermore, the scope was able to readily pass through the anastomosed site of the choledochojejunostomy and, therefore, we observed the interior of the bile duct using the same scope. We obtained an image showing a whitish, papillary‐like tumor, and a biopsy of the tumor rendered the pathology of intraductal papillary mucinous carcinoma. Direct cholangioscopy using DBE is a useful diagnostic tool, particularly in patients with a past history of choledochojejunostomy.

A longitudinal study of FDG-PET in Crohn disease patients receiving granulocyte/monocyte apheresis therapy

BACKGROUND AIMS Endoscopy is the gold standard for the diagnosis and follow-up of patients with Crohn disease (CD). However, a less invasive approach is now being sought for the management of these patients. The objective of this study was to examine whether (18)F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) might be relevant for monitoring the disease activity in CD patients undergoing granulocyte/monocyte apheresis (GMA). METHODS This study was conducted in 12 patients with CD who were receiving treatment with 10 once-a-week GMA sessions with the Adacolumn. The response to treatment was monitored by measuring standard laboratory variables, Crohns Disease Activity Index (CDAI) score, International Organization for the Study of Inflammatory Bowel Diseases (IOIBD) score, and regional and global bowel uptakes on FDG-PET. RESULTS In 6 of the 12 patients, significant improvement of the CDAI was observed after the final session of GMA. The patients who showed clinical response to GMA had a decrease in the regional and global bowel uptakes on FDG-PET, whereas those who did not respond showed no change. In the patients who responded to the GMA, the decrease in regional bowel uptake on FDG-PET in each disease area of the same patient varied in parallel. There was a significant correlation between decrease in the global bowel uptake on FDG-PET and improvement of the CDAI and IOIBD scores. CONCLUSIONS The longitudinal changes in FDG-PET uptakes are of potential clinical interest for assessing the regional and global bowel disease activity in CD patients undergoing GMA therapy.

Roles of high-mobility group box 1 in murine experimental colitis

High-mobility group box 1 (HMGB1) plays a role in inflammatory and immune-mediated diseases. This study investigated the role of HMGB1 in colonic inflammation. Colitis was induced by orally feeding mice 4.5% dextran sulfate sodium (DSS) for up to 7 days. Mice were sacrificed on days 0, 3, 7 and 10, and the colon harvested for the measurement of HMGB1 and pro-inflammatory cytokines. To block HMGB1 induction, an anti-HMGB1 antibody was administered intraperitoneally 2 h before or 3 days after the induction of colitis, and disease severity was assessed by clinical and histological scoring. The colonic levels of tumor necrosis factor-α and interleukin-1β were elevated in relation to disease severity. The level of HMGB1 increased more slowly than that of the cytokines. Immunohistochemical study of the colons showed that the tissues of mice treated with DSS had a higher expression of HMGB1 and its receptor - the receptor for advanced glycation end products - than normal controls, especially in inflammatory infiltrates. The anti-HMGB1 antibody ameliorated tissue damage. In conclusion, HMGB1 is an important mediator of colonic inflammation, and suppression of this protein partially protects against colonic inflammation.

Isolation and characterization of a novel short peptide associated with Crohn's disease

Phage display technology has been utilized to select target molecules against circulating antibodies. The aims of this study were to isolate a peptide that binds with serum from Crohns disease (CD) patients and to examine its diagnostic and pathogenic significance. A phage display library was constructed using cDNA from Caco‐2 cells. Affinity selection using this cDNA library and serum samples from patients with CD was then performed. Phage clones that specifically reacted with the CD sera were then selected using a phage enzyme‐linked immunosorbent assay (ELISA). After the DNA sequences of the selected phages were determined and converted to amino acid sequences, the synthesized peptides were examined using an ELISA. The effect of the synthesized peptides on cytokine release from cultured blood mononuclear cells was investigated. An ELISA analysis for TCP‐353 demonstrated that while 61·7% of the samples from CD patients were seroreactive, seroreactivity was less common among patients with ulcerative colitis (7·3%), acute colitis (0%) or colon cancer (11·4%) and among normal subjects (2·8%). The induction of interleukin (IL)‐1β, IL‐6 and tumour necrosis factor (TNF)‐α release, but not IL‐10 release, in response to TCP‐353 peptide was enhanced in CD mononuclear cells only. We isolated a novel peptide that specifically binds to CD sera and stimulates the proinflammatory responses of CD mononuclear cells. TCP‐353 may have diagnostic, pathogenic and therapeutic significance with regard to the treatment of CD.

Advanced endoscopic features of ulcerative colitis-associated neoplasias: Quantification of autofluorescence imaging

Ulcerative colitis (UC) patients are well known to carry a higher risk of developing colorectal dysplasia/cancer. However, it is hard to detect the lesion in the early phase during colonoscopy. This pilot study was conducted to analyze the endoscopic characteristics of neoplastic lesions associated with UC using advanced imaging techniques. This is a retrospective analysis of 15 colorectal neoplastic lesion obtained from 11 UC patients during remission who underwent white-light- and advanced endoscopic imaging techniques, including chromoendoscopy, narrow-band imaging and autofluorescence imaging (AFI), and were treated with surgery. These lesions were analyzed for histology, location, size, shape, color and endoscopic features. The green/red ratio was also assessed to quantify the AFI intensity. All 11 patients had extensive colitis with the median disease duration of 14.0 years. A total of 15 lesions, consisting of 8 high-grade dysplasia and 7 cancer, was mostly located in the distal colon (86.7%, 13/15) with the mean size of 8.6 mm. The shape was protruding in 46.7% (7/15), flat elevated in 40.0% (6/15) and flat in 13.3% (2/15) and the color was red in 60.0% (9/15), same colored in 33.3% (5/15) and discolored in 6.7% (1/15). The lesion predominantly showed Kudos neoplastic pit pattern in 86.7% (13/15; 5 type IIIL, 7 type IV and 1 type VI) on chromoendoscopy and Sanos neoplastic capillary pattern (type IIIa) in 63.6% (7/11) on narrow-band imaging, but were colored purple as neoplastic lesions in only 37.5% (3/8) on AFI. Of note, the AFI green/red ratio was significantly lower in the neoplastic lesions than UC-involved areas (p=0.00014) and UC-uninvolved areas (p=0.00651) irrespective of the lesions size and histological type. In conclusion, endoscopic analysis based on advanced imaging, in particular AFI quantitation, may be helpful to detect early stage neoplastic lesions in long standing UC. Large-scale, prospective studies are needed.