Ulcerative Colitis: Mei L

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A digest of articles written 1999 and later, on the topic "Colitis, Ulcerative," originating from Planet Earth —» Mei L.  Display:  All Citations ·  All Abstracts
1 Article IBD-associated TL1A gene (TNFSF15) haplotypes determine increased expression of TL1A protein. free! 2009

Michelsen KS, Thomas LS, Taylor KD, Yu QT, Mei L, Landers CJ, Derkowski C, McGovern DP, Rotter JI, Targan SR. · Inflammatory Bowel Disease Center & Immunobiology Research Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA. · PLoS One. · Pubmed #19262684 links to  free full text

Abstract: BACKGROUND: The recently identified member of the TNF superfamily TL1A (TNFSF15) increases IFN-gamma production by T cells in peripheral and mucosal CCR9+ T cells. TL1A and its receptor DR3 are up-regulated during chronic intestinal inflammation in ulcerative colitis and Crohn's disease (CD). TL1A gene haplotypes increase CD susceptibility in Japanese, European, and US cohorts. METHODOLOGY AND PRINCIPAL FINDINGS: Here we report that the presence of TL1A gene haplotype B increases risk in Jewish CD patients with antibody titers for the E. coli outer membrane porin C (OmpC+) (Haplotype B frequency in Jewish CD patients: 24.9% for OmpC negative and 41.9% for OmpC positive patients, respectively, P< or =0.001). CD14+ monocytes isolated from Jewish OmpC+ patients homozygous for TL1A gene haplotype B express higher levels of TL1A in response to FcgammaR stimulation, a known inducing pathway of TL1A, as measured by ELISA. Furthermore, the membrane expression of TL1A is increased on peripheral monocytes from Jewish but not non-Jewish CD patients with the risk haplotype. CONCLUSIONS AND SIGNIFICANCE: These findings suggest that TL1A gene variation exacerbates induction of TL1A in response to FcgammaR stimulation in Jewish CD patients and this may lead to chronic intestinal inflammation via overwhelming T cell responses. Thus, TL1A may provide an important target for therapeutic intervention in this subgroup of IBD patients.

2 Article High-frequency haplotypes in the X chromosome locus TLR8 are associated with both CD and UC in females. 2009

Saruta M, Targan SR, Mei L, Ippoliti AF, Taylor KD, Rotter JI. · Inflammatory Bowel Disease Research Center, Cedars-Sinai Medical Center and the UCLA School of Medicine, Los Angeles, California 90048, USA. · Inflamm Bowel Dis. · Pubmed #18942751 No free full text.

Abstract: BACKGROUND: TNF-alpha and IL-1 have been associated with mucosal inflammation in both Crohn's disease (CD) and ulcerative colitis (UC). Innate immune defects have been associated with CD, specifically CARD15/NOD2. Recently, Toll-like receptor 8 (TLR8) signaling has been shown to enhance generation of both cytokines. Interestingly, TLR8 is located on the X chromosome and inflammatory bowel disease (IBD) has been associated with abnormalities of the X chromosome. The aim was to test whether TLR8 haplotypes are associated with IBD. METHODS: Subjects (735 CD, 343 UC, 245 controls) were genotyped. Single nucleotide polymorphisms (SNPs) were chosen to tag common Caucasian haplotypes. RESULTS: Both "risk (H4)" and "protective (H1)" TLR8 haplotypes were observed associated with CD in females. Eighteen percent of CD females had H4 compared with 9% of controls (P = 0.02). Fifty-nine percent of CD females had H1 compared with 72% of controls (P = 0.01). H1 was also negatively associated with UC in females (59% of UC, 72% of controls P = 0.03). Diplotype analysis of CD, UC, and all IBD in females revealed that 2 protective haplotypes (H1/H1) had a markedly diminished odds ratio, 0.4-0.5. The presence of a risk haplotype (H4 / not H1) had a significantly increased odds ratio, 2.0-2.2. Thus, the risk for IBD was 4-5 times higher in females with 1 risk haplotype than with the protective/protective diplotype. CONCLUSIONS: TLR8 is an X-linked IBD susceptibility gene with both common predisposing and protecting haplotypes. These associations further emphasize the importance of genetic variation in innate immunity as determinants, not only of CD, but of UC as well.

3 Article MAGI2 genetic variation and inflammatory bowel disease. 2009

McGovern DP, Taylor KD, Landers C, Derkowski C, Dutridge D, Dubinsky M, Ippoliti A, Vasiliauskas E, Mei L, Mengesha E, King L, Pressman S, Targan SR, Rotter JI. · Medical Genetics Institute & Inflammatory Bowel Disease Center, Cedars-Sinai Medical Center, Los Angeles, California 90048, USA. · Inflamm Bowel Dis. · Pubmed #18720471 No free full text.

Abstract: BACKGROUND: Despite recent advances the majority of inflammatory bowel disease (IBD) susceptibility 'genes' remain undiscovered. Recent data suggest that autoimmune conditions may 'share' susceptibility loci. Epidemiological evidence indicates an association between celiac disease and IBD and both conditions demonstrate increased gut permeability. MAGI2, recently implicated in ulcerative colitis (UC) and celiac disease, encodes a scaffolding protein involved in epithelial integrity. Our aim was to test MAGI2 variants for association with IBD and also their role in determining intermediate hereditary phenotypes defined by antibody production to microbial antigens. METHODS: We genotyped 113 MAGI2 single nucleotide polymorphisms (SNPs) in 681 cases of Crohn's disease (CD), 259 UC cases, and 195 controls. RESULTS: The most significant IBD association was in intron 6 (rs2160322, P = 0.009) and both UC (P = 0.006) and CD (P = 0.03) contributed to this association. The most significant CD association was with an intron 2 haplotype (rs7785088/rs323149/rs13246026, P = 0.002). We observed highly significant associations with UC in intron 6 (rs7803276/rs7803705, P = 0.002) and also significant associations in introns 2, 6, and 20. Significant associations were seen with: immunoglobulin G (IgG) anti-Saccharomyces cerevisiae antibodies (ASCA)-positive CD in intron 3 (P = 0.003), intron 6 (P = 0.003), and intron 20 (P = 0.001); anti-CBir1-positive CD in intron 3 (P = 0.0001) and intron 6 (P = 0.008); and anti-outer membrane porin C (OmpC)-positive CD in intron 3 (P = 0.0009), and intron 9 (P = 0.007). Quantitative antibody levels were also associated with variants in intron 4 (anti-IgA ASCA, P = 0.0003 and anti-IgG ASCA, P = 0.0002). CONCLUSIONS: These findings support the significance of the epithelial barrier in IBD pathogenesis.

4 Article [Migration inhibitory factor is involved in experimental colitis induced by intrathecal injection of haptten to rat.] free! 2008

Wu XY, Pan H, Mei L. · Department of Physiology and Pathophysiology, Peking University Health Science Center, Beijing, 100083, China. E-mail: · Sheng Li Xue Bao. · Pubmed #18560735 links to  free full text

Abstract: In recent years, there has emerged academic tendency towards the neurogenic mechanism of ulcerative colitis (UC). As one of the supports to the hypothesis of UC being a neurogenic inflammation, we have built a colitis model by intrathecal (ith) injection of a haptten 2,4-dinitrochlorobenzene (DNCB) to DNCB-sensitized rats. In order to explore further the neuroimmunal mechanism of this colitis model, we here focused on a pro-inflammatory cytokine, migration inhibitory factor (MIF), to observe its expression in rat colon nervous tissue and spinal cord in the colitis induced by ith injection of DNCB. At the same time we also observed the effect of MIF antibody pretreatment on the disease active index (DAI) score and the colon pathology by HE staining in the colitis rats. The results obtained showed that the immunofluorescence intensity of double staining of MIF protein in colon nervous tissue and spinal cord was increased in 0.8% and 1.6% DNCB-induced colitis groups than that in the control (60% ethanol) group. Both the colon pathology and the DAI score were significantly reduced by MIF antibody ith pretreatment. Ith injection of 0.8% DNCB after MIF antibody (1:10, 1:5) pretreatment could only induce lower DAI score (P<0.01 as compared, respectively, to the IgG pretreatment group). The colon pathological changes in ith 0.8% DNCB rats were mild, even little after MIF antibody (1:10, 1:5) pretreatment. These results suggest that MIF in spinal cord and enteric nervous system is possibly involved in the rat colitis induced by ith injection of DNCB, which reflects a neuroimmunal mechanism underlying this kind of colitis. MIF is possibly one of the important neurochemical factors in this experimental colitis, even in the UC.

5 Article Both preoperative perinuclear antineutrophil cytoplasmic antibody and anti-CBir1 expression in ulcerative colitis patients influence pouchitis development after ileal pouch-anal anastomosis. 2008

Fleshner P, Ippoliti A, Dubinsky M, Vasiliauskas E, Mei L, Papadakis KA, Rotter JI, Landers C, Targan S. · Division of Colon and Rectal Surgery, Inflammatory Bowel Disease Center, Cedars-Sinai Medical Center, Los Angeles, California, USA. · Clin Gastroenterol Hepatol. · Pubmed #18378498 No free full text.

Abstract: BACKGROUND & AIMS: Acute pouchitis (AP) and chronic pouchitis (CP) are common after ileal pouch-anal anastomosis (IPAA) for ulcerative colitis. The aim of this study was to assess associations of preoperative perinuclear antineutrophil cytoplasmic antibody (pANCA) and anti-CBir1 flagellin on AP or CP development. METHODS: Patients were assessed prospectively for clinically and endoscopically proven AP (antibiotic responsive) or CP (antibiotic-dependent or refractory to antibiotic therapy). Sera from 238 patients were analyzed for ANCA and anti-CBir1 using an enzyme-linked immunosorbent assay. pANCA(+) patients were substratified into high-level (>100 EU/mL) and low-level (<100 EU/mL) groups. RESULTS: After a median follow-up period of 47 months, 72 patients (30%) developed pouchitis. Pouchitis developed in 36% of pANCA(+) patients versus 16% of pANCA(-) patients (P = .005), 46% of anti-CBir1(+) patients versus 26% of anti-CBir1(-) patients (P = .02), and 54% of 35 pANCA(+)/anti-CBir1(+) patients versus 31% of 136 pANCA(+)/anti-CBir1(-) patients (P = .02). AP developed in 37 pANCA(+) patients (22%) versus 6 pANCA(-) patients (9%) (P = .02), and 12 anti-CBir1(+) patients (26%) versus 31 anti-CBir1(-) patients (16%) (P = .1). Although AP was not influenced by pANCA level, AP was seen in 38% of low-level pANCA(+)/anti-CBir1(+) patients versus 18% low-level pANCA(+)/anti-CBir1(-) patients (P = .03). CP was seen in 29% of high-level pANCA(+) patients versus 11% of low-level pANCA(+) patients (P = .03). CONCLUSIONS: Both pANCA and anti-CBir1 expression are associated with pouchitis after IPAA. Anti-CBir1 increases the incidence of AP only in patients who have low-level pANCA expression, and increases the incidence of CP only in patients who have high-level pANCA expression. Diverse patterns of reactivity to microbial antigens may manifest as different forms of pouchitis after IPAA.

6 Article An SNP linkage scan identifies significant Crohn's disease loci on chromosomes 13q13.3 and, in Jewish families, on 1p35.2 and 3q29. 2008

Shugart YY, Silverberg MS, Duerr RH, Taylor KD, Wang MH, Zarfas K, Schumm LP, Bromfield G, Steinhart AH, Griffiths AM, Kane SV, Barmada MM, Rotter JI, Mei L, Bernstein CN, Bayless TM, Langelier D, Cohen A, Bitton A, Rioux JD, Cho JH, Brant SR. · Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21231, USA. · Genes Immun. · Pubmed #18246054 No free full text.

Abstract: Inflammatory bowel disease (IBD) is a complex genetic disorder of two major phenotypes, Crohn's disease (CD) and ulcerative colitis (UC), with increased risk in Ashkenazi Jews. Twelve genome-wide linkage screens have identified multiple loci, but these screens have been of modest size and have used low-density microsatellite markers. We, therefore, performed a high-density single-nucleotide polymorphism (SNP) genome-wide linkage study of 993 IBD multiply affected pedigrees (25% Jewish ancestry) that contained 1709 IBD-affected relative pairs, including 919 CD-CD pairs and 312 UC-UC pairs. We identified a significant novel CD locus on chromosome 13p13.3 (peak logarithm of the odds (LOD) score=3.98) in all pedigrees, significant linkage evidence on chromosomes 1p35.1 (peak LOD score=3.5) and 3q29 (peak LOD score=3.19) in Jewish CD pedigrees, and suggestive loci for Jewish IBD on chromosome 10q22 (peak LOD score=2.57) and Jewish UC on chromosome 2q24 (peak LOD score=2.69). Nominal or greater linkage evidence was present for most previously designated IBD loci (IBD1-9), notably, IBD1 for CD families at chromosome 16q12.1 (peak LOD score=4.86) and IBD6 in non-Jewish UC families at chromosome 19p12 (peak LOD score=2.67). This study demonstrates the ability of high information content adequately powered SNP genome-wide linkage studies to identify loci not observed in multiple microsatellite-based studies in smaller cohorts.

7 Article Does infliximab influence surgical morbidity of ileal pouch-anal anastomosis in patients with ulcerative colitis? 2007

Schluender SJ, Ippoliti A, Dubinsky M, Vasiliauskas EA, Papadakis KA, Mei L, Targan SR, Fleshner PR. · Division of Colon and Rectal Surgery, Inflammatory Bowel Disease Center, Cedars-Sinai Medical Center, 8737 Beverly Boulevard, Suite 101, Los Angeles, California 90048, USA. · Dis Colon Rectum. · Pubmed #17704969 No free full text.

Abstract: PURPOSE: Since infliximab has been approved for treatment of patients with refractory ulcerative colitis, surgeons will be increasingly faced with operating on patients who have failed therapy with this potent immunosuppressant. This study was designed to compare short-term complications in patients with ulcerative colitis who were treated with and without infliximab before colectomy. METHODS: The charts of patients undergoing ileal pouch-anal anastomosis or subtotal colectomy for refractory ulcerative colitis during the five-year period ending October 2005 were reviewed. Postoperative medical and surgical complications were assessed. RESULTS: Seventeen patients had failed infliximab treatment and 134 patients were never treated with infliximab. Ileal pouch-anal anastomosis was performed in 112 patients (74 percent) and subtotal colectomy in 39 patients (36 percent). There were no deaths. Postoperative complications were observed in 43 patients (28 percent), with no significant difference observed between infliximab-treated (37 percent) and infliximab-untreated patients (27 percent). Of 61 patients (40 percent) treated with preoperative cyclosporine A, 5 patients also had been treated with infliximab. The infliximab and cyclosporine A-treated patient group had an 80 percent complication rate, significantly higher than the 29 percent complication rate noted in the cyclosporine A only-treated group (P = 0.04). CONCLUSIONS: Although preoperative treatment with infliximab alone does not significantly increase the incidence of postoperative complications, using both inflixiamb and cyclosporine A before colectomy in refractory ulcerative colitis is associated with high surgical morbidity.

8 Article TNFSF15 is an ethnic-specific IBD gene. free! 2007

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.

9 Article Anti-flagellin (CBir1) phenotypic and genetic Crohn's disease associations. free! 2007

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.

10 Article Can a meta-analysis answer the question: is mucosectomy and handsewn or double-stapled anastomosis better in ileal pouch-anal anastomosis? 2006

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.

11 Article Familial expression of anti-Escherichia coli outer membrane porin C in relatives of patients with Crohn's disease. 2006

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.

12 Article Pathophysiological significance of a reaction in mouse gastrointestinal tract associated with delayed-type hypersensitivity. free! 2004

Yu WG, Lin P, Pan H, Xiao L, Gong EC, Mei L. · Department of Physiology, Medical College of Yangtze University, Jingzhou, Hubei Province, China. · World J Gastroenterol. · Pubmed #15259076 links to  free full text

Abstract: AIM: To explore the pathophysiological significance of delayed type hypersensitivity (DTH) reaction in mouse gastrointestinal tract induced by an allergen 2,4-dinitrochlorobenzene (DNCB). METHODS: BALB/c mice were randomly divided into control and DTH(1-6) groups. After sensitized by DNCB smeared on the abdominal skin, the mice were challenged with DNCB by gavage or enema. The weight, stool viscosity and hematochezia were observed and accumulated as disease active index (DAI) score; the gastrointestinal motility was represented by active charcoal propulsion rate; the colon pathological score was achieved by macropathology and HE staining of section prepared for microscopy; and the leukocyte migration inhibitory factor (LMIF) activity was determined by indirect capillary assay of the absorbance (A) of migrated leukocytes. RESULTS: Active charcoal propulsion rates of small intestine in the DNCB gavages groups were significantly higher than that in the control group (P<0.01). The DAI scores and pathological score in DNCB enema groups were also higher than that in the control group (P<0.05), and there were significant rises in LMIF activity in DNCB enema groups as compared with control groups (P<0.01). CONCLUSION: Mouse gastrointestinal DTH reaction could be induced by DNCB, which might facilitate the mechanism underlying the ulcerative colitis.