Ulcerative Colitis: van Dieren JM

van Dieren JM, van der Woude CJ, Kuipers EJ, Escher JC, Samsom JN, Blumberg RS, Nieuwenhuis EE. · Laboratory of Pediatrics, Division of Gastroenterology and Nutrition, Department of Gastroenterology and Hepatology, Erasmus MC University Medical Center, and Department of Pediatric Gastroenterology, Sophia Children's Hospital, Rotterdam, the Netherlands. · Inflamm Bowel Dis. · Pubmed #17476670 links to  free full text

Abstract: Natural killer T (NKT) cells are a subset of lymphocytes that express cell surface molecules of both conventional T cells and natural killer cells and share the features of both innate and adaptive immune cells. NKT cells have been proposed to make both protective and pathogenic contributions to inflammatory bowel diseases (IBD). On the one hand, recent studies have shown that these cells are involved in the maintenance of mucosal homeostasis. On the other, NKT cells were shown to play a pathogenic role in human ulcerative colitis. Similar contrasting data have been generated in murine models of IBD. Whether the apparent differences in NKT response patterns depend on variations in NKT antigens and/or on the presence of specific subsets of mucosal NKT cells remains to be elucidated. In this article we review the current literature on intestinal NKT cells and their roles in IBD pathogenesis. Specifically, the nomenclature, NKT antigens, and immune mechanisms of NKT cells within the intestinal mucosa are discussed.

van Dieren JM, van Bodegraven AA, Kuipers EJ, Bakker EN, Poen AC, van Dekken H, Nieuwenhuis EE, van der Woude CJ. · Department of Gastroenterology & Hepatology, Erasmus MC, University Medical Center, Rotterdam, the Netherlands. · Inflamm Bowel Dis. · Pubmed #18825773 No free full text.

Abstract: BACKGROUND: Tacrolimus is a potent immunomodulator that is effective in the systemic treatment of inflammatory bowel diseases (IBD). However, potential toxicity and systemic (side) effects after oral intake limit its use. We investigated the local applicability and safety of tacrolimus for distal colitis. METHODS: Patients with refractory left-sided colitis or proctitis were treated for 4 weeks with a daily tacrolimus 2-4 mg enema or 2 mg suppository. Safety of local tacrolimus treatment was assessed by measurement of whole blood tacrolimus trough levels by monitoring liver and kidney function and blood glucose levels. Efficacy of treatment was assessed by comparing the disease activity index (DAI) in ulcerative colitis (UC) patients and endoscopic and histologic appearances before and after 4 weeks of treatment. RESULTS: Nineteen patients with left-sided colitis (n = 7) or proctitis (n = 12) were treated. Two patients with left-sided colitis had Crohn's disease (CD), the other 17 patients had UC. None of the patients developed side effects. Blood trough levels of tacrolimus were too low to induce systemic immune suppression. Thirteen of 19 patients (3/5 left-sided UC, 0/2 left-sided CD, and 10/12 proctitis) showed clinical improvement of disease activity after 4 weeks of local tacrolimus treatment. Moreover, a significant improvement of histological appearance was observed in the suppository-treated group. CONCLUSIONS: This study demonstrates that local colonic application of tacrolimus 2-4 mg daily in patients with refractory distal colitis is feasible, probably safe, and potentially efficacious, and therefore opens the need for a further, randomized trial.

van Dieren JM, Wink JC, Vissers KJ, van Marion R, Hoogmans MM, Dinjens WN, Schouten WR, Tanke HJ, Szuhai K, Kuipers EJ, van der Woude CJ, van Dekken H. · Department of Gastroenterology and Hepatology, Erasmus Medical Center, Rotterdam, The Netherlands. · Diagn Mol Pathol. · Pubmed #17122649 No free full text.

Abstract: Longstanding ulcerative colitis (UC) is associated with a high risk of developing UC-related colonic adenocarcinoma (UCC). These carcinomas originate from nonadenomatous dysplastic regions referred to as dysplasia associated lesion or mass (DALM). We evaluated chromosomal and microsatellite instability (MSI) in 21 DALM/UCCs. Chromosomal instability was determined by high-resolution array comparative genomic hybridization with a 3500-element BAC-PAC array. MSI was assessed with markers BAT25 and BAT26 and by immunohistochemical analysis of mismatch repair genes. Comparative genomic hybridization revealed frequent losses of array clones (>20% of tumors) at chromosome arms 4p, 5q, and 18q, frequent gains of array clones (>20% of tumors) were found at 1q, 5p, 6p, 7p, 7q, 8p, 8q, 11p, 11q, 12q, 14q, 17q, 19q, 20p, and 20q. The pattern of alterations is dominated by gains on 5p and 20q with loss of 4p, all of which were already present in a patient with carcinoma in situ. Immunohistochemical analysis of mismatch repair genes MLH1, PMS2, MSH2, and MSH6 showed negative immunostaining in 1 neoplasm (5%). MSI of BAT25 and BAT26 was seen in 3 tumors (14%) including the neoplasm with aberrant immunostaining. In conclusion, we constructed a genomic profile of DALM/UCC including several novel genetic alterations. Further, we found a low percentage of MSI. Thus, DALM/UCCs display profound chromosomal instability, but this is not associated with concurrent MSI.