Immune regulation by fungal strain diversity in inflammatory bowel disease.

The fungal microbiota (mycobiota) is an integral part of the complex multikingdom microbial community colonizing the mammalian gastrointestinal tract and has an important role in immune regulation1-6. Although aberrant changes in the mycobiota have been linked to several diseases, including inflammatory bowel disease3-9, it is currently unknown whether fungal species captured by deep sequencing represent living organisms and whether specific fungi have functional consequences for disease development in affected individuals. Here we developed a translational platform for the functional analysis of the mycobiome at the fungal-strain- and patient-specific level. Combining high-resolution mycobiota sequencing, fungal culturomics and genomics, a CRISPR-Cas9-based fungal strain editing system, in vitro functional immunoreactivity assays and in vivo models, this platform enables the examination of host-fungal crosstalk in the human gut. We discovered a rich genetic diversity of opportunistic Candida albicans strains that dominate the colonic mucosa of patients with inflammatory bowel disease. Among these human-gut-derived isolates, strains with high immune-cell-damaging capacity (HD strains) reflect the disease features of individual patients with ulcerative colitis and aggravated intestinal inflammation in vivo through IL-1ß-dependent mechanisms. Niche-specific inflammatory immunity and interleukin-17A-producing T helper cell (TH17 cell) antifungal responses by HD strains in the gut were dependent on the C. albicans-secreted peptide toxin candidalysin during the transition from a benign commensal to a pathobiont state. These findings reveal the strain-specific nature of host-fungal interactions in the human gut and highlight new diagnostic and therapeutic targets for diseases of inflammatory origin.

Microbiota-Induced TNF-like Ligand 1A Drives Group 3 Innate Lymphoid Cell-Mediated Barrier Protection and Intestinal T Cell Activation during Colitis.

Inflammatory bowel disease (IBD) results from a dysregulated interaction between the microbiota and a genetically susceptible host. Genetic studies have linked TNFSF15 polymorphisms and its protein TNF-like ligand 1A (TL1A) with IBD, but the functional role of TL1A is not known. Here, we found that adherent IBD-associated microbiota induced TL1A release from CX3CR1+ mononuclear phagocytes (MNPs). Using cell-specific genetic deletion models, we identified an essential role for CX3CR1+MNP-derived TL1A in driving group 3 innate lymphoid cell (ILC3) production of interleukin-22 and mucosal healing during acute colitis. In contrast to this protective role in acute colitis, TL1A-dependent expression of co-stimulatory molecule OX40L in MHCII+ ILC3s during colitis led to co-stimulation of antigen-specific T cells that was required for chronic T cell colitis. These results identify a role for ILC3s in activating intestinal T cells and reveal a central role for TL1A in promoting ILC3 barrier immunity during colitis.

Whole-genome sequencing of African Americans implicates differential genetic architecture in inflammatory bowel disease.

Whether or not populations diverge with respect to the genetic contribution to risk of specific complex diseases is relevant to understanding the evolution of susceptibility and origins of health disparities. Here, we describe a large-scale whole-genome sequencing study of inflammatory bowel disease encompassing 1,774 affected individuals and 1,644 healthy control Americans with African ancestry (African Americans). Although no new loci for inflammatory bowel disease are discovered at genome-wide significance levels, we identify numerous instances of differential effect sizes in combination with divergent allele frequencies. For example, the major effect at PTGER4 fine maps to a single credible interval of 22 SNPs corresponding to one of four independent associations at the locus in European ancestry individuals but with an elevated odds ratio for Crohn disease in African Americans. A rare variant aggregate analysis implicates Ca2+-binding neuro-immunomodulator CALB2 in ulcerative colitis. Highly significant overall overlap of common variant risk for inflammatory bowel disease susceptibility between individuals with African and European ancestries was observed, with 41 of 241 previously known lead variants replicated and overall correlations in effect sizes of 0.68 for combined inflammatory bowel disease. Nevertheless, subtle differences influence the performance of polygenic risk scores, and we show that ancestry-appropriate weights significantly improve polygenic prediction in the highest percentiles of risk. The median amount of variance explained per locus remains the same in African and European cohorts, providing evidence for compensation of effect sizes as allele frequencies diverge, as expected under a highly polygenic model of disease.

Efficacy and Safety of Ustekinumab for Ulcerative Colitis Through 4 Years: Final Results of the UNIFI Long-Term Maintenance Study.

INTRODUCTION: Ulcerative colitis (UC) is a chronic condition that may require long-term treatment. We report the final efficacy and safety results of the UNIFI long-term extension study of ustekinumab in patients with UC through 4 years. METHODS: Ustekinumab induction responders who completed 44 weeks of maintenance treatment and agreed to enter the long-term extension continued their subcutaneous maintenance therapy (90 mg ustekinumab every 8 or 12 weeks [q8w or q12w] or placebo). Starting at week 56, randomized patients could receive dose adjustment to 90 mg q8w. Symptoms and adverse events were assessed through the study; endoscopic assessment was conducted at week 200. RESULTS: Of the 348 patients randomized to subcutaneous ustekinumab at maintenance baseline (q8w and q12w combined), 55.2% were in symptomatic remission at week 200. A greater proportion of biologic-naive patients (67.2% [117/174]) were in symptomatic remission than those with a history of biologic failure (41.6% [67/161]). Among patients in symptomatic remission at week 200, 96.4% were corticosteroid-free. Of the 171 patients with endoscopic evaluation at week 200, 81.6% (71/87) in the q12w group and 79.8% (67/84) in the q8w group had endoscopic improvement. From weeks 156 to the final safety visit (up to week 220), no deaths, major adverse cardiovascular events, or tuberculosis occurred in patients receiving ustekinumab. Nasopharyngitis, UC worsening, and upper respiratory tract infections were the most frequently reported adverse events. DISCUSSION: The long-term efficacy of ustekinumab maintenance in patients with UC was confirmed through 4 years. No new safety signals were observed. ClinicalTrials.gov number NCT02407236.

Management of Primary Sclerosing Cholangitis and Extraintestinal Disorders in Patients With Ileal Pouches: A Systematic Review.

BACKGROUND: Restorative proctocolectomy with IPAA improves the quality of life in patients with ulcerative colitis by the removal of diseased large bowel and preservation of the natural route of defecation. Although the surgery may improve preexisting extraintestinal manifestations in the joints, skin, and eyes, extraintestinal manifestations, particularly primary sclerosing cholangitis, can persist after colectomy. OBJECTIVES: A systematic review of diagnosis and treatment of liver, joint, skin, and eye manifestations in patients with restorative proctocolectomy and IPAA for ulcerative colitis. DATA SOURCES: PubMed, Google Scholar, and Cochrane database. STUDY SELECTION: Relevant articles on primary sclerosing cholangitis and extraintestinal manifestations in ileal pouches published between January 2001 and July 2023 in English were included on the basis of Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. INTERVENTION: Diagnosis and treatment of primary sclerosing cholangitis and extraintestinal manifestations in patients with restorative proctocolectomy and IPAA were included. MAIN OUTCOME MEASURES: Association between primary sclerosing cholangitis, extraintestinal manifestations, and inflammatory disorders of the pouch and their management. RESULTS: Primary sclerosing cholangitis and extraintestinal manifestations are associated with pouchitis, particularly chronic pouchitis. Primary sclerosing cholangitis is associated with chronic pouchitis, enteritis, and possible pouch neoplasia. However, the disease severity and course of primary sclerosing cholangitis and pouchitis do not appear to be parallel. Despite the fact that oral vancomycin or budesonide have been used to treat primary sclerosing cholangitis-associated pouchitis, their impact on the disease course of primary sclerosing cholangitis is not known. Biological therapy for chronic inflammatory disorders of the pouch may also be beneficial for the concurrent extraintestinal manifestations of the joints, skin, and eyes. However, studies on the correlation between the severity of inflammatory pouch disorders and the severity of joint, skin, and eye diseases are lacking. LIMITATIONS: This is a qualitative, not quantitative, review of case series and case reports. CONCLUSIONS: Primary sclerosing cholangitis and extraintestinal manifestations of the joints, skin, and eyes appear to be associated with inflammatory disorders of the ileal pouch. Although the treatment of pouchitis does not seem to affect the disease course of primary sclerosing cholangitis, effective therapy of inflammatory pouch disorders, particularly with biologics, likely benefits concurrent disorders of the joints, skin, and eyes. See video from the symposium .

CORE-IBD: A Multidisciplinary International Consensus Initiative to Develop a Core Outcome Set for Randomized Controlled Trials in Inflammatory Bowel Disease.

BACKGROUND & AIMS: End points to determine the efficacy and safety of medical therapies for Crohn's disease (CD) and ulcerative colitis (UC) are evolving. Given the heterogeneity in current outcome measures, harmonizing end points in a core outcome set for randomized controlled trials is a priority for drug development in inflammatory bowel disease. METHODS: Candidate outcome domains and outcome measures were generated from systematic literature reviews and patient engagement surveys and interviews. An iterative Delphi process was conducted to establish consensus: panelists anonymously voted on items using a 9-point Likert scale, and feedback was incorporated between rounds to refine statements. Consensus meetings were held to ratify the outcome domains and core outcome measures. Stakeholders were recruited internationally, and included gastroenterologists, colorectal surgeons, methodologists, and clinical trialists. RESULTS: A total of 235 patients and 53 experts participated. Patient-reported outcomes, quality of life, endoscopy, biomarkers, and safety were considered core domains; histopathology was an additional domain for UC. In CD, there was consensus to use the 2-item patient-reported outcome (ie, abdominal pain and stool frequency), Crohn's Disease Activity Index, Simple Endoscopic Score for Crohn's Disease, C-reactive protein, fecal calprotectin, and co-primary end points of symptomatic remission and endoscopic response. In UC, there was consensus to use the 9-point Mayo Clinic Score, fecal urgency, Robarts Histopathology Index or Geboes Score, fecal calprotectin, and a composite primary end point including both symptomatic and endoscopic remission. Safety outcomes should be reported using the Medical Dictionary for Regulatory Activities. CONCLUSIONS: This multidisciplinary collaboration involving patients and clinical experts has produced the first core outcome set that can be applied to randomized controlled trials of CD and UC.

Maternal and Neonatal Outcomes in Vedolizumab and Ustekinumab Exposed Pregnancies: Results from the PIANO registry.

BACKGROUND: Pregnancy outcomes in inflammatory bowel disease (IBD) patients with quiescent disease are similar to the general population. Data from the Pregnancy Inflammatory bowel disease And Neonatal Outcomes (PIANO) registry have demonstrated the safety of anti-tumor necrosis factor alpha (TNFs) agents and thiopurines in pregnancy. The objective of this study was to provide information from the PIANO registry on maternal and fetal outcomes in patients exposed to the newer biologics ustekinumab (UST) and vedolizumab (VDZ). METHODS: In this multicenter prospective observational study, we included pregnant women with singleton pregnancies and a diagnosis of IBD. Questionnaires were administered to women at study intake, each subsequent trimester, delivery, and at 4, 9, and 12 months after birth. Bivariate analyses were utilized to determine the independent effects of specific drug classes on outcomes. The exposure cohorts were VDZ, UST, anti-TNFs, immunomodulators, and combination with anti-TNFs and immunomodulators. All were compared to no exposure and to biologics/immunomodulators. RESULTS: There were 1669 completed pregnancies with 1610 live births. Maternal mean age was 32.1 (SD 4.6) years at delivery with 66 VDZ and 47 UST exposed. Women on UST were more likely to have Crohn's disease. There was no increased risk of spontaneous abortion, small for gestational age, low birth weight, neonatal intensive care unit stay, congenital malformations, or intrauterine growth restriction with in utero VDZ or UST exposure. The rate of preterm birth was lower (0.0%) for UST-exposed as compared to other groups including VDZ (13.8%), anti-TNF (8.2%), combination therapy (14.2%), immunomodulator (12.3%), and unexposed (9.7%)(p = 0.03). Rates of serious infections at birth, 4 months, and within the first 12 months of life were comparable among all groups. Nonserious infections were lower at 12 months in UST exposed pregnancies. There was no increased risk signal for placental complications in the VDZ cohort. UST infant concentrations at birth were increased whereas VDZ concentrations were overall decreased compared to maternal serum drug concentration. CONCLUSION: This analysis of UST and VDZ exposure during pregnancy suggests no increase in complications compared to TNFs, immunomodulators and combination TNFs/immunomodulators. No signal was found for increased placental events with either therapy. Continuation of UST and VDZ throughout pregnancy is recommended.

The Real-World Effectiveness and Safety of Ustekinumab in the Treatment of Crohn's Disease: Results From the SUCCESS Consortium.

INTRODUCTION: We evaluated the real-world effectiveness and safety of ustekinumab (UST) in patients with Crohn's disease (CD). METHODS: This study used a retrospective, multicenter, multinational consortium of UST-treated CD patients. Data included patient demographics, disease phenotype, disease activity, treatment history, and concomitant medications. Cumulative rates of clinical, steroid-free, endoscopic, and radiographic remissions were assessed using time-to-event analysis, and clinical predictors were assessed by using multivariate Cox proportional hazard analyses. Serious infections and adverse events were defined as those requiring hospitalization or treatment discontinuation. RESULTS: A total of 1,113 patients (51.8% female, 90% prior antitumor necrosis factor exposure) were included, with a median follow-up of 386 days. Cumulative rates of clinical, steroid-free, endoscopic, and radiographic remissions at 12 months were 40%, 32%, 39%, and 30%, respectively. Biologic-naive patients achieved significantly higher rates of clinical and endoscopic remissions at 63% and 55%, respectively. On multivariable analyses, prior antitumor necrosis factor (hazard ratio, 0.72; 95% confidence interval, 0.49-0.99) and vedolizumab exposure (hazard ratio, 0.65; 95% confidence interval, 0.48-0.88) were independently associated with lower likelihoods of achieving endoscopic remission. In patients who experienced loss of remission, 77 of 102 (75%) underwent dose optimization, and 44 of 77 (57%) achieved clinical response. An additional 152 of 681 patients (22.3%) were dose-optimized because of primary nonresponse incomplete response to UST, of whom 40.1% (61 of 152) responded. Serious infections occurred in 3.4% of patients while other noninfectious adverse events (lymphoma [n = 1], arthralgia [n = 6], rash [n = 6], headache [n = 3], hepatitis [n = 3], hair loss [n = 3], neuropathy [n = 1], and vasculitis [n = 1]) occurred in 2.4% of patients. DISCUSSION: UST represents a safe and effective treatment option for CD, with 40% of patients from a highly refractory cohort achieving clinical remission by 12 months. The greatest treatment effect of UST was seen in biologic-naive patients, and dose escalation may recapture clinical response.

Impact of Inflammatory Bowel Disease Therapies on Durability of Humoral Response to SARS-CoV-2 Vaccination.

Immunization against the spike protein of SARS-CoV-2 reduces transmission1,2 and severe outcomes. However, little is known regarding the impact of immune-mediated diseases and immunosuppressive medications on the efficacy of vaccination. Vaccination immunity is transient, with breakthrough cases increasing at longer time intervals since the last dose.3,4 Although there are data on SARS-CoV-2 vaccine on early seroconversion in patients with inflammatory bowel disease (IBD),5 no data in the same cohort exist describing the durability of these antibodies over time. We sought to investigate the impact of IBD and its therapies on postvaccination antibody response and kinetics of immunogenicity decline, because these findings may better inform clinical guidelines and recommendations on precautions and booster vaccination.

A Quality Improvement Initiative Is Associated With Reduced Time to Administer Biologics and Small Molecules and Emergency Room Visits in Inflammatory Bowel Disease.

BACKGROUND: Delays in biologic or small molecule medication administration are associated with increased adverse events, hospitalization, and surgery in inflammatory bowel disease (IBD). We evaluated the impact of a quality improvement (QI) intervention on the time to administration of biologics or small molecules (TABS) in IBD. METHODS: Data were retrospectively extracted for IBD patients prescribed biologics or small molecules from a convenience sample of providers participating in an accredited QI educational intervention (baseline cohort). Subsequent to the intervention, data were prospectively collected from patients prescribed these medications (postintervention cohort). Dates related to steps between a treatment decision to medication administration were collected. The primary outcome compared TABS in baseline and postintervention cohorts. RESULTS: Eighteen physicians provided survey and patient data for 200 patients in each cohort (n=400). The median time to medication administration (TABS) decreased from baseline to postintervention cohorts (30 vs. 26 d, P=0.04). Emergency room visits before medication administration also decreased (25.5% vs. 12.5%, P=0.001). Similar numerical TABS reductions were observed in subgroups limited to physicians providing patients to both cohorts and for individual medications prescribed. Primary contributors to delays included filling prescriptions subsequent to insurance approval and dispensation subsequent to this. CONCLUSIONS: A QI intervention successfully reduced medication administration times (TABS) by accelerating provider-dependent steps. This intervention was associated with reduced emergency room visits. We propose TABS as a quality metric to assess the effective delivery of therapies in IBD. Further evaluation of QI interventions, patient education on prescription drug insurance, and quality metrics are warranted.

Anti-TL1A Antibody PF-06480605 Safety and Efficacy for Ulcerative Colitis: A Phase 2a Single-Arm Study.

BACKGROUND & AIMS: An immune component of inflammatory bowel disease is up-regulated tumor necrosis factor-like ligand 1A (TL1A). Anti-TL1A antibodies such as PF-06480605, a fully human immunoglobulin G1 monoclonal antibody, may have therapeutic potential. METHODS: This Phase 2a, multicenter, single-arm, open-label study (TUSCANY) evaluated safety, tolerability, efficacy, pharmacokinetics, and immunogenicity in PF-06480605-treated participants with moderate to severe ulcerative colitis (UC). Participants received 500 mg intravenous PF-06480605 every 2 weeks, 7 doses total, with a 3-month follow-up period. Primary safety and efficacy endpoints were the incidence of adverse events (AEs) and week 14 endoscopic improvement (EI) (Mayo endoscopic subscore = 0 or 1), respectively. Secondary endpoints included total soluble TL1A (free/drug-bound) (sTL1A), incidence of anti-drug and neutralizing antibodies, PF-06480605 concentrations, and changes in fecal calprotectin and high-sensitivity C-reactive protein. Histology was assessed at week 14. RESULTS: The study enrolled 50 participants; 42 completed. Of 109 treatment-emergent AEs, 18 were treatment-related. The most common AEs were UC disease exacerbation and arthralgia (6 participants each). Four serious AEs, no deaths, and no malignancies were reported. Week 14 EI was observed in a statistically significant proportion of participants (38.2% [uniformly minimum-variance unbiased estimator, per protocol population]). Minimal histologic disease was observed after treatment (Robarts Histopathology Index ≤5: 33.3%; Geboes Index ≤3.2: 47.6%). sTL1A increase over time from baseline indicated sustained target engagement. Forty-one participants (82%) tested positive for anti-drug antibodies and 5 (10%) for neutralizing antibodies. CONCLUSIONS: PF-06480605 demonstrated an acceptable safety profile and statistically significant EI in participants with moderate to severe UC, warranting further study in a larger participant cohort. Tissue histopathology analyses support this conclusion. TRIAL REGISTRATION NUMBER: https://clinicaltrials.gov/NCT02840721.

Digital Health Apps in the Clinical Care of Inflammatory Bowel Disease: Scoping Review.

BACKGROUND: Digital health is poised to transform health care and redefine personalized health. As Internet and mobile phone usage increases, as technology develops new ways to collect data, and as clinical guidelines change, all areas of medicine face new challenges and opportunities. Inflammatory bowel disease (IBD) is one of many chronic diseases that may benefit from these advances in digital health. This review intends to lay a foundation for clinicians and technologists to understand future directions and opportunities together. OBJECTIVE: This review covers mobile health apps that have been used in IBD, how they have fit into a clinical care framework, and the challenges that clinicians and technologists face in approaching future opportunities. METHODS: We searched PubMed, Scopus, and ClinicalTrials.gov to identify mobile apps that have been studied and were published in the literature from January 1, 2010, to April 19, 2019. The search terms were ("mobile health" OR "eHealth" OR "digital health" OR "smart phone" OR "mobile app" OR "mobile applications" OR "mHealth" OR "smartphones") AND ("IBD" OR "Inflammatory bowel disease" OR "Crohn's Disease" (CD) OR "Ulcerative Colitis" (UC) OR "UC" OR "CD"), followed by further analysis of citations from the results. We searched the Apple iTunes app store to identify a limited selection of commercial apps to include for discussion. RESULTS: A total of 68 articles met the inclusion criteria. A total of 11 digital health apps were identified in the literature and 4 commercial apps were selected to be described in this review. While most apps have some educational component, the majority of apps focus on eliciting patient-reported outcomes related to disease activity, and a few are for treatment management. Significant benefits have been seen in trials relating to education, quality of life, quality of care, treatment adherence, and medication management. No studies have reported a negative impact on any of the above. There are mixed results in terms of effects on office visits and follow-up. CONCLUSIONS: While studies have shown that digital health can fit into, complement, and improve the standard clinical care of patients with IBD, there is a need for further validation and improvement, from both a clinical and patient perspective. Exploring new research methods, like microrandomized trials, may allow for more implementation of technology and rapid advancement of knowledge. New technologies that can objectively and seamlessly capture remote data, as well as complement the clinical shift from symptom-based to inflammation-based care, will help the clinical and health technology communities to understand the full potential of digital health in the care of IBD and other chronic illnesses.

A Frameshift in CSF2RB Predominant Among Ashkenazi Jews Increases Risk for Crohn's Disease and Reduces Monocyte Signaling via GM-CSF.

BACKGROUND & AIMS: Crohn's disease (CD) has the highest prevalence in Ashkenazi Jewish populations. We sought to identify rare, CD-associated frameshift variants of high functional and statistical effects. METHODS: We performed exome sequencing and array-based genotype analyses of 1477 Ashkenazi Jewish individuals with CD and 2614 Ashkenazi Jewish individuals without CD (controls). To validate our findings, we performed genotype analyses of an additional 1515 CD cases and 7052 controls for frameshift mutations in the colony-stimulating factor 2-receptor ß common subunit gene (CSF2RB). Intestinal tissues and blood samples were collected from patients with CD; lamina propria leukocytes were isolated and expression of CSF2RB and granulocyte-macrophage colony-stimulating factor-responsive cells were defined by adenomatous polyposis coli (APC) time-of-flight mass cytometry (CyTOF analysis). Variants of CSF2RB were transfected into HEK293 cells and the expression and functions of gene products were compared. RESULTS: In the discovery cohort, we associated CD with a frameshift mutation in CSF2RB (P = 8.52 × 10(-4)); the finding was validated in the replication cohort (combined P = 3.42 × 10(-6)). Incubation of intestinal lamina propria leukocytes with granulocyte-macrophage colony-stimulating factor resulted in high levels of phosphorylation of signal transducer and activator of transcription (STAT5) and lesser increases in phosphorylation of extracellular signal-regulated kinase and AK straining transforming (AKT). Cells co-transfected with full-length and mutant forms of CSF2RB had reduced pSTAT5 after stimulation with granulocyte-macrophage colony-stimulating factor, compared with cells transfected with control CSF2RB, indicating a dominant-negative effect of the mutant gene. Monocytes from patients with CD who were heterozygous for the frameshift mutation (6% of CD cases analyzed) had reduced responses to granulocyte-macrophage colony-stimulating factor and markedly decreased activity of aldehyde dehydrogenase; activity of this enzyme has been associated with immune tolerance. CONCLUSIONS: In a genetic analysis of Ashkenazi Jewish individuals, we associated CD with a frameshift mutation in CSF2RB. Intestinal monocytes from carriers of this mutation had reduced responses to granulocyte-macrophage colony-stimulating factor, providing an additional mechanism for alterations to the innate immune response in individuals with CD.

Characterization of genetic loci that affect susceptibility to inflammatory bowel diseases in African Americans.

BACKGROUND & AIMS: Inflammatory bowel disease (IBD) has familial aggregation in African Americans (AAs), but little is known about the molecular genetic susceptibility. Mapping studies using the Immunochip genotyping array expand the number of susceptibility loci for IBD in Caucasians to 163, but the contribution of the 163 loci and European admixture to IBD risk in AAs is unclear. We performed a genetic mapping study using the Immunochip to determine whether IBD susceptibility loci in Caucasians also affect risk in AAs and identify new associated loci. METHODS: We recruited AAs with IBD and without IBD (controls) from 34 IBD centers in the United States; additional controls were collected from 4 other Immunochip studies. Association and admixture loci were mapped for 1088 patients with Crohn's disease, 361 with ulcerative colitis, 62 with IBD type unknown, and 1797 controls; 130,241 autosomal single-nucleotide polymorphisms (SNPs) were analyzed. RESULTS: The strongest associations were observed between ulcerative colitis and HLA rs9271366 (P = 7.5 × 10(-6)), Crohn's disease and 5p13.1 rs4286721 (P = 3.5 × 10(-6)), and IBD and KAT2A rs730086 (P = 2.3 × 10(-6)). Additional suggestive associations (P < 4.2 × 10(-5)) were observed between Crohn's disease and IBD and African-specific SNPs in STAT5A and STAT3; between IBD and SNPs in IL23R, IL12B, and C2orf43; and between ulcerative colitis and SNPs near HDAC11 and near LINC00994. The latter 3 loci have not been previously associated with IBD, but require replication. Established Caucasian associations were replicated in AAs (P < 3.1 × 10(-4)) at NOD2, IL23R, 5p15.3, and IKZF3. Significant admixture (P < 3.9 × 10(-4)) was observed for 17q12-17q21.31 (IZKF3 through STAT3), 10q11.23-10q21.2, 15q22.2-15q23, and 16p12.2-16p12.1. Network analyses showed significant enrichment (false discovery rate <1 × 10(-5)) in genes that encode members of the JAK-STAT, cytokine, and chemokine signaling pathways, as well those involved in pathogenesis of measles. CONCLUSIONS: In a genetic analysis of 3308 AA IBD cases and controls, we found that many variants associated with IBD in Caucasians also showed association evidence with these diseases in AAs; we also found evidence for variants and loci not previously associated with IBD. The complex genetic factors that determine risk for or protection against IBD in different populations require further study.

Id1 expression in endothelial cells of the colon is required for normal response to injury.

Inhibitor of DNA binding (ID)-1 is important for angiogenesis during embryogenesis and tumor development. Whether ID1 expression in endothelial cells of the colon is required for normal response to injury is unknown. We demonstrate that Id1 is up-regulated in colonic endothelial cells in an experimental model of colitis and in the inflamed mucosa of patients with inflammatory bowel disease. Because prostaglandin E2 and tumor necrosis factor-α are also elevated in colitis, we determined whether these factors could induce ID1 transcription in cultured endothelial cells. Tumor necrosis factor-α stimulated ID1 transcription via early growth response 1 protein (Egr-1). By contrast, the induction of ID1 by prostaglandin E2 was mediated by cAMP response element-binding protein (CREB). To determine whether the increased ID1 levels in the endothelial cells of inflamed mucosa were an adaptive response that modulated the severity of tissue injury, Id1 was conditionally depleted in the endothelium of mice, which sensitized the mice to more severe chemical colitis, including more severe diarrhea, bleeding, and histological injury, and shorter colon compared with control mice. Moreover, depletion of Id1 in the vasculature was associated with increased CD31(+) aggregates and increased vascular permeability in inflamed mucosa compared with those in Id1 wild-type control mice. These results suggest that endothelial ID1 up-regulation in inflamed colonic mucosa is an adaptive response that modulates the severity of tissue injury.

Crohn's Disease: Evolution, Epigenetics, and the Emerging Role of Microbiome-Targeted Therapies.

Crohn's disease (CD) is a chronic, systemic, immune-mediated inflammation of the gastrointestinal tract. Originally described in 1932 as non-caseating granulomatous inflammation limited to the terminal ileum, it is now recognized as an expanding group of heterogeneous diseases defined by intestinal location, extent, behavior, and systemic extraintestinal manifestations. Joint diseases, including inflammatory spondyloarthritis and ankylosing spondylitis, are the most common extraintestinal manifestations of CD and share more genetic susceptibility loci than any other inflammatory bowel disease (IBD) trait. The high frequency and overlap with genes associated with infectious diseases, specifically Mendelian susceptibility to mycobacterial diseases (MSMD), suggest that CD may represent an evolutionary adaptation to environmental microbes. Elucidating the diversity of the enteric microbiota and the protean mucosal immune responses in individuals may personalize microbiome-targeted therapies and molecular classifications of CD. This review will focus on CD's natural history and therapies in the context of epigenetics, immunogenetics, and the microbiome.

Exercise and Self-Reported Limitations in Patients with Inflammatory Bowel Disease.

BACKGROUND: Limited evidence suggests that exercise may have beneficial, anti-inflammatory effects in patients with inflammatory bowel disease (IBD). AIMS: The purpose of this study was to evaluate the prevalence of exercise in patients with IBD and the limitations they experience secondary to their disease. METHODS: Two hundred and fifty IBD patients were prospectively enrolled in this study at an academic medical center at the time of their outpatient visits between March and October 2013. Subjects were asked to complete a one-time survey that asks questions about medical and surgical history, exercise frequency and intensity, and the limitations and barriers they experience. RESULTS: Two hundred and twenty-seven patients (148 female patients) completed the survey. Crohn's disease was present in 140 patients (61.5 %), while 87 had ulcerative colitis. Forty-one patients (16.4 %) never exercised, 82 patients (32.8 %) exercised 1-2 times per week, 59 (23.6 %) exercised 3-4 times per week, and 45 (18.0 %) exercised more than four times per week. Of the 186 who regularly exercise, 95 (51 %) reported moderate exercise intensity, 61 (33 %) reported light intensity, and 30 (16 %) reported vigorous intensity. Ninety-nine patients (44 %) reported that their IBD limited their exercise for reasons including fatigue (n = 81), joint pain (n = 37), embarrassment (n = 23), weakness (n = 21), and others. CONCLUSIONS: Although they may benefit from exercise, IBD patients experience considerable barriers to regular exercise secondary to the relapsing and remitting nature of IBD. Larger studies are needed to determine the effects of exercise on disease symptomatology and activity.

Adenocarcinoma of the ileal pouch mucosa: case report and literature review.

PURPOSE: Cancers developing near the site of the ileoanal pouch anastomosis (IPAA) have been reported, but uncommonly in the ileal pouch mucosa itself. We present a recently encountered case of ileal pouch cancer and review the literature to examine the prevalence, risk factors, and natural history of ileal pouch adenocarcinoma as well as pouch surveillance. METHODS: A chart review of the case from our institution was conducted, and a PubMed search was undertaken for articles describing adenocarcinoma arising from the ileal pouch mucosa. RESULTS: Twenty articles containing 26 cases were reviewed in addition to our described case. More than half were reported in the last decade. Only three cases were definitively stage 1. All seven patients who underwent regular surveillance were diagnosed with stage 1 or 2 disease. Seventeen patients had neoplasia in their original proctocolectomy specimen and six did not. The mean time from pouch creation to adenocarcinoma was 8.9 years. CONCLUSIONS: The risk of developing ileal pouch mucosa adenocarcinoma appears low. However, increasing reports of these cancers are concerning as most patients present with advanced disease after many years. Patients with a previous history of dysplasia/cancer may be at increased risk. We believe surveillance after IPAA should include the anal transition zone and the ileal pouch mucosa. The establishment of expert consensus guidelines on pouch surveillance should be considered in the near future.