Ulcerative Colitis: Yang H

Picornell Y, Mei L, Taylor K, Yang H, Targan SR, Rotter JI. · Medical Genetics Institute, Cedars-Sinai Medical Center Los Angeles, California, USA. · Inflamm Bowel Dis. · Pubmed #17663424 links to  free full text

Abstract: BACKGROUND: Inflammatory bowel disease (IBD) is a clinically and, likely, genetically heterogeneous group of disorders. A recent report suggests that genetic variations in the TNFSF15 gene contribute to the susceptibility of IBD in both Japanese and Caucasian populations. The aim was to confirm the association between TNFSF15 high- and low-risk haplotypes and IBD in a Caucasian population. METHODS: Five single-nucleotide polymorphisms (SNPs) that comprise the 2 common haplotypes were genotyped in 599 Caucasian patients with Crohn's disease (CD), 382 Caucasian patients with ulcerative colitis (UC), and 230 ethnically matched healthy controls, including both Jews and non-Jews. RESULTS: The previously reported 'risk' haplotype was not associated with CD or UC (88.2% in CD cases versus 88.3% in controls, P = 0.96; 88.1% in UC cases versus 88.3% in controls, P = 0.78). We did, however, observe an increased frequency of the "protective" haplotype in non-Jewish controls for both CD and UC (38.8% CD cases versus 50% controls, P = 0.01; 37.3% UC cases versus 50% controls, P = 0.01) with no such effect observed in the Jewish samples. There was an interactive effect between ethnicity and the protective haplotype in CD (P = 0.04). CONCLUSIONS: We observed a protective haplotype, consisting of the minor alleles for all 5 markers, to have a higher frequency in the non-Jewish controls than in CD and UC. Of further interest, the haplotype frequency was in the opposite direction in our Jewish case-control panels (both CD and UC), leading us to conclude 1) that TNFSF15 is indeed an IBD susceptibility gene, and 2) the disease susceptibility is ethnic-specific.

De Jager PL, Franchimont D, Waliszewska A, Bitton A, Cohen A, Langelier D, Belaiche J, Vermeire S, Farwell L, Goris A, Libioulle C, Jani N, Dassopoulos T, Bromfield GP, Dubois B, Cho JH, Brant SR, Duerr RH, Yang H, Rotter JI, Silverberg MS, Steinhart AH, Daly MJ, Podolsky DK, Louis E, Hafler DA, Rioux JD, Anonymous00242, Anonymous00243. · Department of Neurology, Center for Neurologic Diseases, Brigham & Women's Hospital and Harvard Medical School, Boston, MA, USA. · Genes Immun. · Pubmed #17538633 No free full text.

Abstract: The intestinal flora has long been thought to play a role either in initiating or in exacerbating the inflammatory bowel diseases (IBD). Host defenses, such as those mediated by the Toll-like receptors (TLR), are critical to the host/pathogen interaction and have been implicated in IBD pathophysiology. To explore the association of genetic variation in TLR pathways with susceptibility to IBD, we performed a replication study and pooled analyses of the putative IBD risk alleles in NFKB1 and TLR4, and we performed a haplotype-based screen for association to IBD in the TLR genes and a selection of their adaptor and signaling molecules. Our genotyping of 1539 cases of IBD and pooled analysis of 4805 cases of IBD validates the published association of a TLR4 allele with risk of IBD (odds ratio (OR): 1.30, 95% confidence interval (CI): 1.15-1.48; P=0.00017) and Crohn's disease (OR: 1.33, 95% CI: 1.16-1.54; P=0.000035) but not ulcerative colitis. We also describe novel suggestive evidence that TIRAP (OR: 1.16, 95% CI: 1.04-1.30; P=0.007) has a modest effect on risk of IBD. Our analysis, therefore, offers additional evidence that the TLR4 pathway - in this case, TLR4 and its signaling molecule TIRAP - plays a role in susceptibility to IBD.

Jiang L, Xia B, Li J, Ye M, Deng C, Ding Y, Luo H, Ren H, Hou X, Liu H, Xu H, Cheng H, Yang H. · Department of Internal Medicine and Geriatrics of Zhongnan Hospital, Wuhan University School of Medicine, Wuhan, PR China. · J Clin Gastroenterol. · Pubmed #17426467 No free full text.

Abstract: BACKGROUND AND AIMS: Cigarette smoking, alcohol use, appendectomy, and family history of inflammatory bowel disease (IBD) have all been shown to be associated with IBD, but there were no reports of risk factors for IBD in a Chinese population in which the incidence of IBD is increasing during the past decade. We conducted a case-control study to examine associations between previously reported environmental risk factors and development of ulcerative colitis (UC) in Wuhan city, central China. METHODS: A total of 177 patients with UC and 177 age-matched and sex-matched controls were prospectively studied in Wuhan city from January 2004 to December 2004. An age-matched and sex-matched case-control study was conducted to assess the role of smoking, alcohol use, appendectomy, and other potential risk factors in the development of UC by a detailed questionnaire. RESULTS: Smoking was a protective factor and exsmoking is a risk factor for UC [compared with nonsmokers, smokers: odds ratios (OR)=0.28, 95% confidence intervals (CI): 0.16-0.48, P=0.0001; exsmokers: OR=4.36, 95%CI: 1.46-13.04, P=0.008]. Positive family history of IBD was a risk factor (OR=4.35, 95%CI: 1.21-15.71, P=0.025) whereas appendectomy was a protective factor (OR=0.24, 95%CI: 0.07-0.86, P=0.028) for UC. There were no significant associations between UC and other factors examined. CONCLUSIONS: Although the incidence of UC in Chinese is relatively lower than that in white, the same risk factors for UC that were reported in white populations were associated with Chinese UC patients. Specifically, smoking was a protective factor for UC and exsmoking was associated with an increase risk of UC in a Chinese population. Family history of IBD was shown to be a risk for UC, whereas appendectomy was associated with a low risk for UC.

Spencer AU, Yang H, Haxhija EQ, Wildhaber BE, Greenson JK, Teitelbaum DH. · Department of Surgery, Section of Pediatric Surgery, University of Michigan, Ann Arbor, MI 48109, USA. · Dig Dis Sci. · Pubmed #17342403 links to  free full text

Abstract: Ulcerative colitis is characterized by elevated rates of epithelial cell apoptosis, and an up-regulation of pro-apoptotic cytokines including tumor necrosis factor alpha (TNF-alpha). Recently, angiotensin converting enzyme (ACE) has been shown to promote apoptosis. In addition, pharmacologic ACE inhibition (ACE-I) both prevents apoptosis and reduces TNF-alpha expression in vitro. We hypothesized that ACE-I, using enalaprilat, would decrease colonic epithelial cell apoptosis and reduce colitis severity in the dextran sulfate sodium (DSS)-induced colitis model in mice. We assessed the severity of colitis, and colonic epithelial cell apoptosis, after administration of DSS. Mice were given either daily ACE-I treatment or daily placebo. ACE-I treatment markedly improved clinical outcomes. In addition, ACE-I treatment significantly reduced the maximum histopathologic colitis grade. ACE-I also dramatically reduced the epithelial apoptotic rate. To investigate the mechanism by which ACE-I reduced apoptosis; we measured TNF-alpha, Bcl-2, and Bax expression. TNF-alpha mRNA was significantly lower with ACE-I treatment compared to placebo at every time point, as was the ratio of Bax to Bcl-2. We conclude that ACE-I reduces the severity of DSS-induced colitis and reduces epithelial cell apoptosis.

Papadakis KA, Yang H, Ippoliti A, Mei L, Elson CO, Hershberg RM, Vasiliauskas EA, Fleshner PR, Abreu MT, Taylor K, Landers CJ, Rotter JI, Targan SR. · Cedars-Sinai Inflammatory Bowel Disease Center, Los Angeles, California, USA. · Inflamm Bowel Dis. · Pubmed #17260364 links to  free full text

Abstract: BACKGROUND: Antibody reactivity to microbial antigens correlates with distinct Crohn's disease (CD) phenotypes such as fistulizing or fibrostenosing disease. We examined the association between anti-CBir1 and clinical phenotypes and NOD2 variants in a large cohort of adult CD patients. METHODS: Sera and genomic DNA were collected from 731 patients with CD and tested for immune responses to I2, CBir1, oligomannan, and outer membrane porin C (OmpC) and the 3 most common CD-associated NOD2 variants. RESULTS: Anti-CBir1 reactivity was significantly associated with fibrostenosis (FS), internal penetrating (IP) disease phenotypes, small bowel (SB) involvement, and SB surgery but negatively associated with ulcerative colitis (UC)-like CD. Multivariate logistic regression analysis showed that anti-CBir1 was independently associated with FS and UC-like CD irrespective of the antibody reactivity to I2, oligomannan, or OmpC, but not with SB involvement or SB surgery. The magnitude of anti-CBir1 reactivity, when added to the quantitative response toward the other 3 CD-associated antigens, enhances the discrimination of FS, IP, UC-like CD, and SB involvement, but not SB surgery. Finally, although the frequency of anti-CBir1 was similar in patients with none versus at least 1 NOD2 variant, the quantitative response to CBir1 flagellin was significantly higher in patients with CD carrying at least 1 NOD2 variant versus those carrying no variants (median anti-CBir1 titer 33.39 versus 28.36, respectively; P = 0.01). CONCLUSIONS: Anti-CBir1 serum reactivity in CD patients is independently associated with FS and complicated SB CD. Quantitative, but not qualitative, response to CBir1 is also significantly associated with the CD-associated NOD2 variants.

Silverberg MS, Duerr RH, Brant SR, Bromfield G, Datta LW, Jani N, Kane SV, Rotter JI, Philip Schumm L, Hillary Steinhart A, Taylor KD, Yang H, Cho JH, Rioux JD, Daly MJ, Anonymous00254. · Department of Medicine, Mount Sinai Hospital IBD Centre, University of Toronto, Toronto, Ontario, Canada. · Eur J Hum Genet. · Pubmed #17213842 links to  free full text

Abstract: Although the general association of the inflammatory bowel disease (IBD) 5 region on chromosome 5q31 to Crohn's disease (CD) has been replicated repeatedly, the identity of the precise causal variant within the region remains unknown. A recent report proposed polymorphisms in solute carrier family 22, member 4 (SLC22A4) organic cation transporter 1(OCTN1) and solute carrier family 22, member 5 (SLC22A5) (OCTN2) as responsible for the IBD5 association, but definitive, large-sample comparison of those polymorphisms with others known to be in strong linkage disequilibrium was not performed. We evaluated 1879 affected offspring and parents ascertained by a North American IBD Genetics Consortium for six IBD5 tag single nucleotide polymorphisms (SNPs) to evaluate association localization and ethnic and subphenotypic specificity. We confirm association to the IBD5 region (best SNP IGR2096a_1/rs12521868, P<0.0005) and show this association to be exclusive to the non-Jewish (NJ) population (P=0.00005) (risk allele undertransmitted in Ashkenazi Jews). Using Phase II HapMap data, we demonstrate that there are a set of polymorphisms, spanning genes from prolyl 4-hydroxylase (P4HA2) through interferon regulatory factor 1 (IRF1) with equivalent statistical evidence of association to the reported SLC22A4 variant and that each, by itself, could entirely explain the IBD5 association to CD. Additionally, the previously reported SLC22A5 SNP is rejected as the potential causal variant. No specificity of association was seen with respect to disease type and location, and a modest association to ulcerative colitis is also observed. We confirm the importance of IBD5 to CD susceptibility, demonstrate that the locus may play a role in NJ individuals only, and establish that IRF1, PDLIM, and P4HA2 may be equally as likely to contain the IBD5 causal variant as the OCTN genes.

Duerr RH, Taylor KD, Brant SR, Rioux JD, Silverberg MS, Daly MJ, Steinhart AH, Abraham C, Regueiro M, Griffiths A, Dassopoulos T, Bitton A, Yang H, Targan S, Datta LW, Kistner EO, Schumm LP, Lee AT, Gregersen PK, Barmada MM, Rotter JI, Nicolae DL, Cho JH. · Division of Gastroenterology, Hepatology and Nutrition, Department of Medicine, School of Medicine, University of Pittsburgh, University of Pittsburgh Medical Center Presbyterian, Mezzanine Level, C-Wing, 200 Lothrop Street, Pittsburgh, PA 15213, USA. · Science. · Pubmed #17068223 links to  free full text

Abstract: The inflammatory bowel diseases Crohn's disease and ulcerative colitis are common, chronic disorders that cause abdominal pain, diarrhea, and gastrointestinal bleeding. To identify genetic factors that might contribute to these disorders, we performed a genome-wide association study. We found a highly significant association between Crohn's disease and the IL23R gene on chromosome 1p31, which encodes a subunit of the receptor for the proinflammatory cytokine interleukin-23. An uncommon coding variant (rs11209026, c.1142G>A, p.Arg381Gln) confers strong protection against Crohn's disease, and additional noncoding IL23R variants are independently associated. Replication studies confirmed IL23R associations in independent cohorts of patients with Crohn's disease or ulcerative colitis. These results and previous studies on the proinflammatory role of IL-23 prioritize this signaling pathway as a therapeutic target in inflammatory bowel disease.

Schluender SJ, Mei L, Yang H, Fleshner PR. · Division of Colon and Rectal Surgery, Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, California, USA. · Am Surg. · Pubmed #17058734 No free full text.

Abstract: Although ileal pouch-anal anastomosis (IPAA) is the procedure of choice for polyposis and ulcerative colitis with medically refractory disease or dysplasia, controversy exists concerning whether mucosal preservation with double-stapled (DS) IPAA is superior to mucosectomy and handsewn (HS) IPAA anastomosis for postoperative function. Prospective studies have shown no statistically significant differences. The use of meta-analysis can strengthen statistical power by combining the data from related studies. A meta-analysis was performed to determine whether there was a significant difference in functional and manometric outcome between HS-IPAA and DS-IPAA. Prospective, randomized studies were identified using a literature search. Functional outcome variables included number of normal continence, minor incontinence, nocturnal evacuation, the ability to discriminate flatus from stool, and antidiarrheal medication. Manometric outcomes included postoperative resting and squeeze anal pressures. Four prospective, randomized trials were identified. Of the 184 total patients, the HS-IPAA group included 86 patients (48 men and 38 women) and the DS-IPAA group included 98 patients (49 men and 49 women). There were no significant differences in functional outcome between HS-IPAA and DS-IPAA. In addition, there was no significant difference in sphincter resting and squeeze pressures between the two patient groups. This meta-analysis demonstrates that DS-IPAA offers no advantage in functional or manometric outcome when compared with HS-IPAA.

Nguyen GC, Torres EA, Regueiro M, Bromfield G, Bitton A, Stempak J, Dassopoulos T, Schumm P, Gregory FJ, Griffiths AM, Hanauer SB, Hanson J, Harris ML, Kane SV, Orkwis HK, Lahaie R, Oliva-Hemker M, Pare P, Wild GE, Rioux JD, Yang H, Duerr RH, Cho JH, Steinhart AH, Brant SR, Silverberg MS. · Harvey M. and Lyn P. Meyerhoff Inflammatory Bowel Disease Center, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA. · Am J Gastroenterol. · Pubmed #16696785 No free full text.

Abstract: OBJECTIVES: Inflammatory bowel disease (IBD), comprising primarily of Crohn's disease (CD) and ulcerative colitis (UC), is increasingly prevalent in racial and ethnic minorities. This study was undertaken to characterize racial differences in disease phenotype in a predominantly adult population. METHODS: Phenotype data on 830 non-Hispanic white, 127 non-Hispanic African American, and 169 Hispanic IBD patients, recruited from six academic centers, were abstracted from medical records and compiled in the NIDDK-IBD Genetics Consortium repository. We characterized racial differences in family history, disease location and behavior, surgical history, and extraintestinal manifestations (EIMs) using standardized definitions. RESULTS: African American CD patients were more likely than whites to develop esophagogastroduodenal CD (OR = 2.8; 95% CI: 1.4-5.5), colorectal disease (OR = 1.9; 95% CI: 1.1-3.4), perianal disease (OR = 1.7; 95% CI: 1.03-2.8), but less likely to have ileal involvement (OR = 0.55; 95% CI: 0.32-0.96). They were also at higher risk for uveitis (OR = 5.5; 95% CI: 2.3-13.0) and sacroiliitis (OR = 4.0; 95% CI: 1.55-10.1). Hispanics had higher prevalence of perianal CD (OR = 2.9; 95% CI: 1.8-4.6) and erythema nodosum (3.3; 95% CI: 1.7-6.4). Among UC patients, Hispanics had more proximal disease extent. Both African American and Hispanic CD patients, but not UC patients, had lower prevalences of family history of IBD than their white counterparts. CONCLUSIONS: There are racial differences in IBD family history, disease location, and EIMs that may reflect underlying genetic variations and have important implications for diagnosis and management of disease. These findings underscore the need for further studies in minority populations.

Mei L, Targan SR, Landers CJ, Dutridge D, Ippoliti A, Vasiliauskas EA, Papadakis KA, Fleshner PR, Rotter JI, Yang H. · Medical Genetics Institute, Cedars-Sinai Medical Center, Los Angeles, California 90048, USA. · Gastroenterology. · Pubmed #16618402 No free full text.

Abstract: BACKGROUND & AIMS: Crohn's disease (CD) is a genetically complex disorder with strong familial aggregation. Pathogenesis appears to involve dysregulation of the immune response to endogenous bacteria. Anti-Escherichia coli outer membrane porin C (anti-OmpC) expression reflects an exaggerated response to commensal bacteria and occurs with higher frequency in CD. The aim of this study was to determine whether there is familial aggregation and genetic determination of anti-OmpC expression in CD families. METHODS: Study groups consisted of 787 CD patients, 389 ulcerative colitis (UC) patients, 619 unaffected relatives, and 216 healthy controls. Serum anti-OmpC was detected by enzyme-linked immunosorbent assay. RESULTS: CD patients had a greater percentage of anti-OmpC than UC patients and healthy controls. Anti-OmpC expression was more frequent in unaffected relatives from CD-only or mixed families, compared with healthy controls (P = .002 and .0001, respectively), and it was more frequent in UC patients from mixed families than those from UC-only families (P = .02). There was a significant familiality in anti-OmpC expression: P = .02 for qualitative concordance and P < .0001 for quantitative intraclass correlation. The heritability estimate for anti-OmpC level was .39 (P < .0001). CONCLUSIONS: Anti-OmpC is a heritable immunophenotype. Increased anti-OmpC expression in the unaffected family members of CD patients suggests that anti-OmpC may be an immunologic risk marker for CD. That UC patients in mixed families had a higher response to OmpC than those in UC-only families indicates pathophysiologic heterogeneity within UC.

Achkar JP, Dassopoulos T, Silverberg MS, Tuvlin JA, Duerr RH, Brant SR, Siminovitch K, Reddy D, Datta LW, Bayless TM, Zhang L, Barmada MM, Rioux JD, Steinhart AH, McLeod RS, Griffiths AM, Cohen Z, Yang H, Bromfield GP, Schumm P, Hanauer SB, Cho JH, Nicolae DL. · Center for Inflammatory Bowel Disease, Department of Gastroenterology, Cleveland Clinic Foundation, Cleveland, OH, USA. · Am J Gastroenterol. · Pubmed #16542294 No free full text.

Abstract: OBJECTIVES: The complete elucidation of genetic variants that contribute to inflammatory bowel disease (IBD) will likely include variants that increase risk to both Crohn's disease and ulcerative colitis as well as variants that increase risk for particular phenotypic subsets. The purpose of this study was to assess phenotypic subsets that contribute to the major IBD susceptibility loci. METHODS: This linkage study encompassed 904 affected relative pairs, representing the largest combined phenotyped cohort to date, and allowing for meaningful subset analyses. Genetic linkage data were stratified by disease location and age at diagnosis. RESULTS: We establish that some loci, notably the IBD3 and chromosome 3q linkage regions demonstrate contributions from both small intestine and colon cohorts, whereas others, notably the IBD1 (NOD2/CARD15) and IBD2 regions increase risk for small intestine or colon inflammation, respectively. The strongest linkage evidence in this study was for the subset of extensive ulcerative colitis in the region of IBD2 (lod 3.27; p < 0.001). Evidence for linkage in the region of NOD2/CARD15 (IBD1) was stronger for the subset of Crohn's patients with ileal disease (lod 2.56; p= 0.035) compared to the overall Crohn's group, consistent with previous findings that NOD2/CARD15 variants are associated with ileal disease. CONCLUSIONS: Analyses incorporating disease location in IBD increase the power and enhance the accuracy of genomic localization. Our data provide strong evidence that extensive ulcerative colitis represents a pathophysiologic subset of IBD.

Targan SR, Landers CJ, Yang H, Lodes MJ, Cong Y, Papadakis KA, Vasiliauskas E, Elson CO, Hershberg RM. · Cedars-Sinai Inflammatory Bowel Disease Center, Los Angeles, California 90048, USA. · Gastroenterology. · Pubmed #15940634 No free full text.

Abstract: BACKGROUND & AIMS: Antibody responses to certain microbial antigens define heterogeneous groups of Crohn's patients; multiple and high-level responses to these antigens are associated with aggressive clinical phenotypes. The flagellin, CBir1, identified by investigations in the C3H/HeJBir mouse model, has been identified as a dominant antigen capable of inducing colitis in mice and eliciting antibody responses in a subpopulation of patients with Crohn's disease (CD). The aim of this study was to evaluate serum response to CBir1 flagellin in CD patients and to compare this response to responses defined previously to oligomannan (anti-Saccharomyces cerevisiae antibody), I2, OmpC, and neutrophil nuclear autoantigens (pANCA), and to determine anti-CBir1-associated phenotypes. METHODS: A total of 484 sera from the Cedars Sinai Medical Center repository, previously typed for anti-Saccharomyces cerevisiae antibody, anti-I2, anti-OmpC, and pANCA were tested for anti-CBir1 by enzyme-linked immunosorbent assay, and results were assessed for clinical phenotype associations. RESULTS: The presence and level of immunoglobulin G anti-CBir1 were associated with CD independently. Anti-CBir1 was present in all antibody subgroups and expression increased in parallel with increases in the number of antibody responses. pANCA+ CD patients were more reactive to CBir1 than were pANCA+ ulcerative colitis patients. Anti-CBir1 expression is associated independently with small-bowel, internal-penetrating, and fibrostenosing disease features. CONCLUSIONS: Serum responses to CBir1 independently identify a unique subset of patients with complicated CD. This bacterial antigen was identified in a murine model and has a similar pattern of aberrant reactivity in a subset of CD patients.

Pierik M, Yang H, Barmada MM, Cavanaugh JA, Annese V, Brant SR, Cho JH, Duerr RH, Hugot JP, McGovern DP, Paavola-Sakki P, Radford-Smith GL, Pavli P, Silverberg MS, Schreiber S, Taylor KD, Vlietinck R, Anonymous00395. · Department of Gastroenterology, University Hospital Gasthuisberg, Leuven, Belgium. · Inflamm Bowel Dis. · Pubmed #15674107 No free full text.

Abstract: BACKGROUND AND AIMS: The inflammatory bowel diseases (IBDs) Crohn's disease (CD) and ulcerative colitis are complex disorders with an important genetic determinant. One gene associated with CD has been identified: NOD2/CARD15. Two independent genome-wide scans found significant evidence (logarithm of odds [LOD] 3.6) and suggestive evidence (LOD 2.8) for linkage on locus 14q11-12, also known as the IBD4 locus. To further characterize this locus, we assessed gene-environment interaction (IBD4 x smoking) and phenotypic heterogeneity in a large cohort of IBD-affected sibling pairs as part of an ongoing international collaborative effort. PATIENTS AND METHODS: A total of 733 IBD families, comprising 892 affected sibling pairs, were genotyped for microsatellites D14S261, D14S283, D14S972, and D14S275, spanning the IBD4 locus. Information on gender, ethnicity, age at onset, smoking at diagnosis, extraintestinal manifestations, and disease location was available. RESULTS: A significant distortion in the mean allele sharing (MAS) between affected siblings was observed for CD patients only at each of the four markers (54.6%, 52.8%, 50.4%, and 53.3%, respectively). Maximum linkage for CD was observed at marker D14S261 (multipoint nonparametric linkage score 2.36; P </= 0.01; MAS 54.6%). MAS was higher in CD families in which all siblings or at least one sibling smoked compared with nonsmoking CD families (MAS, 58.90%, 57.50%, and 52.80%, respectively). CONCLUSIONS: The IBD International Genetics Consortium replicated the IBD4 locus on chromosome 14q for CD and also showed evidence for a gene-environment interaction at this locus. Further studies are needed to explore the mechanism by which smoking influences IBD4.

Abreu MT, Kantorovich V, Vasiliauskas EA, Gruntmanis U, Matuk R, Daigle K, Chen S, Zehnder D, Lin YC, Yang H, Hewison M, Adams JS. · Division of Gastroenterology, Inflammatory Bowel Disease Center, Steven Spielberg Pediatric Research Center, Burns and Allen Research Institute, Los Angeles, CA 90048, USA. · Gut. · Pubmed #15247180 links to  free full text

Abstract: OBJECTIVES: Many patients with Crohn's disease (CD) have low bone mineral density (BMD) that may not be solely attributable to glucocorticoid use. We hypothesised that low BMD in patients with CD is associated with elevated circulating levels of the active form of vitamin D, 1,25-dihydroxyvitamin D (1,25(OH)(2)D). We further hypothesised that this was secondary to increased synthesis of 1,25(OH)(2)D by inflammatory cells in the intestine. The aim of this study was to examine the relationship between 1,25(OH)(2)D levels and BMD in patients with CD. METHODS: An IRB approved retrospective review of medical records from patients with CD (n = 138) or ulcerative colitis (UC, n = 29). Measurements of vitamin D metabolites and immunoreactive parathyroid hormone (iPTH) were carried out. BMD results were available for 88 CD and 20 UC patients. Immunohistochemistry or real time reverse transcription-polymerase chain reaction (RT-PCR) for the enzyme 1alpha-hydroxylase was performed on colonic biopsies from patients with CD (14) or UC (12) and normal colons (4). RESULTS: Inappropriately high levels of serum 1,25(OH)(2)D (>60 pg/ml) were observed in 42% of patients with CD compared with only 7% in UC, despite no differences in mean iPTH. Serum 1,25(OH)(2)D levels were higher in CD (57 pg/ml) versus UC (41 pg/ml) (p = 0.0001). In patients with CD, there was a negative correlation between 1,25(OH)(2)D levels and lumbar BMD (r = -0.301, p = 0.005) independent of therapeutic glucocorticoid use. 1,25(OH)(2)D levels also correlated with CD activity. Lastly, immunohistochemistry and RT-PCR demonstrated increased expression of intestinal 1alpha-hydroxylase in patients with CD. CONCLUSIONS: These data demonstrate that elevated 1,25(OH)(2)D is more common in CD than previously appreciated and is independently associated with low bone mineral density. The source of the active vitamin D may be the inflamed intestine. Treatment of the underlying inflammation may improve metabolic bone disease in this subgroup of patients.

Yang H, Ohmen JD, Ma Y, Bentley LG, Targan SR, Fischel-Ghodsian N, Rotter JI. · Department of Medicine, Cedars-Sinai Research Institute, Cedars-Sinai Medical Center, Los Angeles 90048, USA. · Genet Med. · Pubmed #11256672 No free full text.

Abstract: PURPOSE: The inflammatory bowel diseases (IBD), Crohn's disease (CD), and ulcerative colitis (UC) are chronic intestinal disorder of unknown etiology. Genetic factors play an important role in the pathogenesis of these diseases, but with a complex pattern of inheritance. A number of genome-wide scans have identified several putative susceptibility loci for both CD and UC, including a locus on chromosome 12 reported in a set of British families. We aim to evaluate the linkage between CD or UC and this chromosome 12 locus in an independent set of U.S. Caucasian families (36% being of Ashkenazi Jewish origin). METHODS: Microsatellite markers along chromosome 12 spaced at approximately 10 cm intervals were used to test the putative loci in CD only families (65 sib pairs from 46 families). Regions with positive linkage for CD were then tested in a panel of UC and mixed families (44 sib pairs from 29 families). Two point linkage analysis was performed with SIBPAL. Multipoint linkage analysis was carried out with MAPMAKER/SIBS. RESULTS: We observed evidence of linkage between the region on chromosome 12 and Crohn's disease, because there was a significant excess of allele sharing in CD sib pairs (pi = 0.62, p = 0.0004 from two-point linkage; and logarithm of the odds score (LOD) = 2.0 from multipoint linkage). However, we did not observe the same linkage in UC and mixed families (p = 0.48; not significant [ns]). CONCLUSION: Our data provided further evidence that the region on chromosome 12 is likely to contain a gene predisposing to CD.

Vasiliauskas EA, Kam LY, Karp LC, Gaiennie J, Yang H, Targan SR. · Department of Medicine, Cedars-Sinai Medical Center and the UCLA School of Medicine, Los Angeles, CA 90048, USA. · Gut. · Pubmed #10986208 links to  free full text

Abstract: BACKGROUND: Perinuclear antineutrophil cytoplasmic antibodies (pANCA) have been detected in a clinically distinct Crohn's disease subpopulation. Antibodies to Saccharomyces cerevisiae (ASCA) have been demonstrated in the majority of patients with Crohn's disease. AIMS: To examine the relationship between selective marker antibody expression in Crohn's disease and disease onset, location, and clinical behaviour patterns. METHODS: Sera from 156 consecutive patients with established Crohn's disease were evaluated in a blinded fashion for the presence of ASCA and ANCA. Clinical profiles were generated by investigators blinded to immune marker status. RESULTS: Using multiple regression analyses, higher ASCA levels were shown to be independently associated with early age of disease onset as well as both fibrostenosing and internal penetrating disease behaviours. Higher ANCA levels were associated with later age of onset and ulcerative colitis-like behaviour. Substratification of the Crohn's disease population using selective ANCA and ASCA expression (high levels of a single marker antibody): (1) distinguished homogeneous subgroups that manifested similar disease location and behaviours; and (2) identified patients with more aggressive small bowel disease. CONCLUSIONS: The findings suggest that by taking into account the magnitude of the host immune response, Crohn's disease can now be stratified on an immunological basis into more homogeneous clinically distinct subgroups, characterised by greater uniformity among anatomical distribution of disease and disease behaviour.

Trachtenberg EA, Yang H, Hayes E, Vinson M, Lin C, Targan SR, Tyan D, Erlich H, Rotter JI. · Children's Hospital Oakland Research Institute, Oakland, CA, USA. · Hum Immunol. · Pubmed #10689124 No free full text.

Abstract: Ulcerative colitis (UC) and Crohn's disease (CD) are the clinical entities comprising idiopathic inflammatory bowel disease (IBD). Previous studies on the association of IBD and human leukocyte antigen (HLA) class II genes suggested a role for HLA in this disease. Here we present HLA class II (DRB1, DQB1, DQA1, DPB1) allele and haplotype distributions determined using the polymerase chain reaction and sequence-specific oligonucleotide probe methods. A total of 578 UC and CD Caucasian patients and controls from Jewish (Ashkenazi) and non-Jewish populations was examined. Our previously reported association of DR1-DQ5 with CD was attributable to DRB1*0103. A dramatic association with IBD and the highly unusual DRB1*0103-DQA1*0501-DQB1*0301 haplotype (OR = 6.6, p = 0.036) was found. The more common DR1 haplotype, DRB1*0103-DQA1*0101-DQB1*0501, was also associated with IBD (OR = 3.1, p = 0.014), a result suggesting that interaction between DR and DQ may determine the extent of disease risk. Our previously reported association of DR2 with UC was attributable to DRB1*1502 (OR = 2.6, p = 0.006). At the DPB1 locus, a significant association of DPB1*0401 with CD was observed for the combined populations (OR = 1.85, p = 0.007). These observations indicate that some class II alleles and haplotypes confer susceptibility to both UC and CD, implying common immunogenetic mechanisms of pathogenesis, while others confer risk to only one of these diseases, and illustrate the value of DNA HLA typing in disease susceptibility analyses.

Ma Y, Ohmen JD, Li Z, Bentley LG, McElree C, Pressman S, Targan SR, Fischel-Ghodsian N, Rotter JI, Yang H. · Parke-Davis Laboratory for Molecular Genetics (PDLMG), Alameda, California, USA. · Inflamm Bowel Dis. · Pubmed #10579120 No free full text.

Abstract: Chronic inflammatory bowel disease (IBD) presents as two major clinical forms, Crohn's disease (CD) and ulcerative colitis (UC). Genetic epidemiological studies and animal models suggest that inherited factors play significant roles in the susceptibility to both forms of IBD. From four genome-wide scans, putative susceptibility loci on chromosome 16 (IBD1 for CD), and on chromosomes 1, 3, 4, 6, 7, 10, and 12 for IBD, have been identified. Several other groups, including ours, have confirmed linkage to the loci on chromosomes 12 and 16. The aim of this study is to identify other potential susceptibility loci for CD with a genome-wide search approach. In our sample of 222 individuals from 46 families (20 Jewish and 26 non-Jewish), with a total of 65 sibpairs diagnosed with CD, we observed a novel locus with suggestive linkage [multipoint logarithm of the odds score (Mlod) > 2] at chromosome 14q11.2 (Mlod = 2.8, p = 0.0002). In addition, suggestive linkage was observed in our Jewish families at chromosome 17q21-q23 (Mlod = 2.1, p = 0.01) and chromosome 5q33-q35 (Mlod = 2.2, p = 0.0003). The syntenic regions of the latter locus are mapped within two putative loci on mouse chromosomes 11 and 18, which were identified in a mouse IBD model induced by dextran sulfate sodium (29). Our preliminary results provide potential evidence for several susceptibility loci contributing to the risk of CD. The observation of man-mouse synteny may accelerate the identification of CD susceptibility gene(s) on human chromosome 5.

Tountas NA, Casini-Raggi V, Yang H, Di Giovine FS, Vecchi M, Kam L, Melani L, Pizarro TT, Rotter JI, Cominelli F. · Division of Gastroenterology, University of Virginia Health Sciences Center, Charlottesville, Virginia, USA. · Gastroenterology. · Pubmed #10500062 No free full text.

Abstract: BACKGROUND & AIMS: The role of the interleukin (IL)-1 receptor antagonist (IL-1ra) in predisposing an individual to inflammatory bowel disease (IBD) is controversial. This study aimed to determine the association between intron 2 IL-1ra polymorphism and IBD by performing a multiethnic case-control study and to assess its functional significance. METHODS: A total of 236 patients with ulcerative colitis (UC), 196 patients with Crohn's disease (CD), and 338 ethnically matched control patients treated at LAC-USC and Cedars-Sinai Medical Centers and the University of Milan Medical Center were genotyped for a variable length polymorphism in intron 2 of the IL-1ra gene (IL-1RN). Total IL-1ra protein production rates in peripheral blood mononuclear cells (PBMCs) were correlated with carriage of allele 2 of the IL-1RN gene (IL-1RN*2). RESULTS: In the LAC-USC group, UC patients (n = 60) had an increased frequency of at least 1 copy of IL-1RN*2 compared with controls (n = 129) (70% vs. 33%; P < 0.01; odds ratio [OR], 4.7). The frequency of IL-1RN*2 carriage in the Cedars-Sinai group was 59% in UC, 45% in CD, and 42% in controls (P < 0.01; OR, 2.0). A significant difference was observed only in the Jewish subgroup (P = 0.003; OR, 5.0). The association was not detected in UC or CD patients treated at the University of Milan. The ORs of 4.7 and 5.0 appear to be the highest reported in any UC population for any genetic markers. Further, carriage of IL-1RN*2 was associated with decreased production of total IL-1ra protein in cultured PBMCs from both UC patients and controls. CONCLUSIONS: These results provide further evidence that IL-1ra is important in the predisposition to UC, there may be genetic or pathogenetic heterogeneity between different ethnic groups, and UC and CD are genetically distinct diseases.

Swallow DM, Vinall LE, Gum JR, Kim YS, Yang H, Rotter JI, Mirza M, Lee JC, Lennard-Jones JE. · No affiliation provided · J Med Genet. · Pubmed #10636731 links to  free full text

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