Use of azathioprine in IBD: modern aspects of an old drug.
Louis, Edouard ; ;
in Gut (2014), 63(11), 1695-9Detailed reference viewed: 9 (0 ULg)
Role of endoscopy, cross-sectional imaging and biomarkers in Crohn's disease monitoring.
; Meuwis, Marie-Alice ; et al
in Gut (2013), 62(12), 1806-16
Crohn's disease is characterised by recurrent and/or chronic inflammation of the gastrointestinal tract leading to cumulative intestinal tissue damage. Treatment tailoring to try to prevent this tissue ... [more ▼]
Crohn's disease is characterised by recurrent and/or chronic inflammation of the gastrointestinal tract leading to cumulative intestinal tissue damage. Treatment tailoring to try to prevent this tissue damage as well as achieve optimal benefit/risk ratio over the whole disease course is becoming an important aspect of Crohn's disease management. For decades, clinical symptoms have been the main trigger for diagnostic procedures and treatment strategy adaptations. However, the correlation between symptoms and intestinal lesions is only weak. Furthermore, preliminary evidence suggests that a state of remission beyond the simple control of clinical symptoms, and including mucosal healing, may be associated with better disease outcome. Therefore monitoring the disease through the use of endoscopy and cross-sectional imaging is proposed. However, the degree of mucosal or bowel wall healing that needs to be reached to improve disease outcome has not been appropriately studied. Furthermore, owing to their invasive nature and cost, endoscopy and cross-sectional imaging are not optimal tools for the patients or the payers. The use of biomarkers as surrogate markers of intestinal and systemic inflammation might help. Two biomarkers have been most broadly assessed in Crohn's disease: C-reactive protein and faecal calprotectin. These markers correlate significantly with endoscopic lesions, with the risk of relapse and with response to therapy. They could be used to help make decisions about diagnostic procedures and treatment. In particular, with the use of appropriate threshold values, they could determine the need for endoscopic or medical imaging procedures to confirm the disease activity state. [less ▲]Detailed reference viewed: 28 (3 ULg)
Genetic and microbial factors modulating the ubiquitin proteasome system in inflammatory bowel disease.
; ; et al
in Gut (2013)
OBJECTIVE: Altered microbiota composition, changes in immune responses and impaired intestinal barrier functions are observed in IBD. Most of these features are controlled by proteases and their ... [more ▼]
OBJECTIVE: Altered microbiota composition, changes in immune responses and impaired intestinal barrier functions are observed in IBD. Most of these features are controlled by proteases and their inhibitors to maintain gut homeostasis. Unrestrained or excessive proteolysis can lead to pathological gastrointestinal conditions. The aim was to validate the identified protease IBD candidates from a previously performed systematic review through a genetic association study and functional follow-up. DESIGN: We performed a genetic association study in a large multicentre cohort of patients with Crohn's disease (CD) and UC from five European IBD referral centres in a total of 2320 CD patients, 2112 UC patients and 1796 healthy controls. Subsequently, we did an extensive functional assessment of the candidate genes to explore their causality in IBD pathogenesis. RESULTS: Ten single nucleotide polymorphisms (SNPs) in four genes were significantly associated with CD: CYLD, USP40, APEH and USP3. CYLD was the most significant gene with the intronically located rs12324931 the strongest associated SNP (pFDR=1.74e-17, OR=2.24 (1.83 to 2.74)). Five SNPs in four genes were significantly associated with UC: USP40, APEH, DAG1 and USP3. CYLD, as well as some of the other associated genes, is part of the ubiquitin proteasome system (UPS). We therefore determined if the IBD-associated adherent-invasive Escherichia coli (AIEC) can modulate the UPS functioning. Infection of intestinal epithelial cells with the AIEC LF82 reference strain modulated the UPS turnover by reducing poly-ubiquitin conjugate accumulation, increasing 26S proteasome activities and decreasing protein levels of the NF-kappaB regulator CYLD. This resulted in IkappaB-alpha degradation and NF-kappaB activation. This activity was very important for the pathogenicity of AIEC since decreased CYLD resulted in increased ability of AIEC LF82 to replicate intracellularly. CONCLUSIONS: Our results reveal the UPS, and CYLD specifically, as an important contributor to IBD pathogenesis, which is favoured by both genetic and microbial factors. [less ▲]Detailed reference viewed: 22 (1 ULg)
Rate of Malignancies and Infections in a Large Single Center Cohort of IBD Patients Treated With Thiopurines and Anti-TNF-Antibodies.
; ; et al
in Gut (2011)Detailed reference viewed: 16 (0 ULg)
H1N1 vaccines in a large observational cohort of patients with inflammatory bowel disease treated with immunomodulators and biological therapy.
; ; et al
in Gut (2011), 60(4), 456-62
BACKGROUND: Safety data are lacking on influenza vaccination in general and on A (H1N1)v vaccination in particular in patients with inflammatory bowel disease (IBD) receiving immmunomodulators and/or ... [more ▼]
BACKGROUND: Safety data are lacking on influenza vaccination in general and on A (H1N1)v vaccination in particular in patients with inflammatory bowel disease (IBD) receiving immmunomodulators and/or biological therapy. AIMS AND METHODS: The authors conducted a multicentre observational cohort study to evaluate symptoms associated with influenza H1N1 adjuvanted (Pandemrix, Focetria, FluvalP) and non-adjuvanted (Celvapan) vaccines and to assess the risk of flare of IBD after vaccination. Patients with stable IBD treated with immunomodulators and/or biological therapy were recruited from November 2009 until March 2010 in 12 European countries. Harvey-Bradshaw Index and Partial Mayo Score were used to assess disease activity before and 4 weeks after vaccination in Crohn's disease (CD) and ulcerative colitis (UC). Vaccination-related events up to 7 days after vaccination were recorded. RESULTS: Of 575 patients enrolled (407 CD, 159 UC and nine indeterminate colitis; 53.9% female; mean age 40.3 years, SD 13.9), local and systemic symptoms were reported by 34.6% and 15.5% of patients, respectively. The most common local and systemic reactions were pain in 32.8% and fatigue in 6.1% of subjects. Local symptoms were more common with adjuvanted (39.3%) than non-adjuvanted (3.9%) vaccines (p < 0.0001), whereas rates of systemic symptoms were similar with both types (15.0% vs 18.4%, p = 0.44). Among the adjuvanted group, Pandemrix more often induced local reactions than FluvalP and Focetria (51.2% vs 27.6% and 15.4%, p < 0.0001). Solicited adverse events were not associated with any patient characteristics, specific immunomodulatory treatment, or biological therapy. Four weeks after vaccination, absence of flare was observed in 377 patients with CD (96.7%) and 151 with UC (95.6%). CONCLUSION: Influenza A (H1N1)v vaccines are well tolerated in patients with IBD. Non-adjuvanted vaccines are associated with fewer local reactions. The risk of IBD flare is probably not increased after H1N1 vaccination. [less ▲]Detailed reference viewed: 24 (3 ULg)
Effects of haptoglobin polymorphisms and deficiency on susceptibility to inflammatory bowel disease and on severity of murine colitis.
; ; et al
in Gut (2011), 61(4), 528-534
BackgroundHaptoglobin (Hp) is a haemoglobin-binding protein with immunomodulatory properties. Its gene (16q22) harbours a common polymorphism with two different alleles: Hp1 and Hp2. Genotype Hp22 has ... [more ▼]
BackgroundHaptoglobin (Hp) is a haemoglobin-binding protein with immunomodulatory properties. Its gene (16q22) harbours a common polymorphism with two different alleles: Hp1 and Hp2. Genotype Hp22 has been shown to be over-represented in different immune diseases. Results in Crohn's disease (CD) are contradictory.AimsTo determine whether Hp plays a role in inflammatory bowel disease, both genetically and functionally.Methods1061 patients with CD, 755 with ulcerative colitis (UC) and 152 with primary sclerosing cholangitis, as well as 452 healthy controls, were genotyped using touch-down PCR. To confirm association results, 464 CD trios and 151 UC trios were genotyped. Serum Hp concentrations were determined in 62 individuals of different genotype. Colitis was induced in mice with dextran sulphate sodium (DSS) and oxazolone (Oxa). Cytokine production was evaluated by mRNA quantification in colonic tissue and ELISA on supernatants of mesenteric lymph node cells.ResultsPrevalence of Hp2 was higher in CD and UC than in controls. In the confirmatory cohorts, Hp2 was over-transmitted to the affected offspring. Serum Hp concentrations were higher in individuals with genotypes Hp11 and Hp21 than in those with Hp22 (1.38 vs 0.89 g/l). DSS- and Oxa-induced colitis were more severe in Hp-deficient mice than in control mice and accompanied by higher concentrations (although not statistically significantly different) of tissue mRNA for cytokines. Interleukin-17 production was significantly higher in the presence of Hp-deficient serum compared with wild-type serum.ConclusionsThe Hp gene may play a role in susceptibility to inflammatory bowel disease. Its implication in other immune diseases underscores the common pathways between these diseases. Experimental models of colitis showed that Hp has a protective role in inflammatory colitis, most likely by inhibiting the production of Th1 and Th17 cytokines. [less ▲]Detailed reference viewed: 41 (6 ULg)
Immortal time bias and infliximab-related mortality and malignancy incidence
; Van Steen, Kristel ; et al
in Gut (2010), 59Detailed reference viewed: 10 (2 ULg)
Reanalysis of death risk in long-term follow-up in infliximab patients versus controls
; Van Steen, Kristel ; et al
in Gut (2010), 59Detailed reference viewed: 12 (6 ULg)
Tolerability of shortened infliximab infusion times in patients with inflammatory bowel disease: a single center cohort study
; ; et al
in Gut (2010)Detailed reference viewed: 4 (1 ULg)
Molecular Reclassification of Crohn’s Disease by cluster analysis of genetic variants
; Mahachie John, Jestinah ; et al
in Gut (2009)Detailed reference viewed: 26 (20 ULg)
The impact of infliximab therapy on intestinal mucosal expression of matrix metalloproteinase and ADAM genes in patients with inflammatory bowel disease.
; ; et al
in Gut (2009)Detailed reference viewed: 10 (4 ULg)
Long-term outcome of treatment with infliximab in 614 patients with Crohn's disease: results from a single-centre cohort
; ; et al
in Gut (2009), 58(4), 492-500
BACKGROUND AND AIMS: This observational study assessed the long-term clinical benefit of infliximab (IFX) in 614 consecutive patients with Crohn's disease (CD) from a single centre during a median follow ... [more ▼]
BACKGROUND AND AIMS: This observational study assessed the long-term clinical benefit of infliximab (IFX) in 614 consecutive patients with Crohn's disease (CD) from a single centre during a median follow-up of 55 months (interquartile range (IQR) 27-83). METHODS: The primary analysis looked at the proportion of patients with initial response to IFX who had sustained clinical benefit at the end of follow-up. The long-term effects of IFX on the course of CD as reflected by the rate of surgery and hospitalisations and need for corticosteroids were also analysed. RESULTS: 10.9% of patients were primary non-responders to IFX. Sustained benefit was observed in 347 of the 547 patients (63.4%) receiving long-term treatment. In 68.3% of these, treatment with IFX was ongoing and in 31.7% IFX was stopped, with the patient being in remission. Seventy patients (12.8%) had to stop IFX due to side effects and 118 (21.6%) due to loss of response. Although the yearly drop-out rates of IFX in patients with episodic (10.7%) and scheduled treatment (7.1%) were similar, the need for hospitalisations and surgery decreased less in the episodic than in the scheduled group. Steroid discontinuation also occurred in a higher proportion of patients in the scheduled group than in the episodic group. CONCLUSIONS: In this large real-life cohort of patients with CD, long-term treatment with IFX was very efficacious to maintain improvement during a median follow-up of almost 5 years and changed disease outcome by decreasing the rate of hospitalisations and surgery. [less ▲]Detailed reference viewed: 27 (4 ULg)
Mucosal gene signatures to predict response to infliximab in patients with ulcerative colitis
; ; et al
in Gut (2009), 58(12), 1612-9
BACKGROUND AND AIMS: Infliximab is an effective treatment for ulcerative colitis with over 60% of patients responding to treatment and up to 30% reaching remission. The mechanism of resistance to anti ... [more ▼]
BACKGROUND AND AIMS: Infliximab is an effective treatment for ulcerative colitis with over 60% of patients responding to treatment and up to 30% reaching remission. The mechanism of resistance to anti-tumour necrosis factor alpha (anti-TNFalpha) is unknown. This study used colonic mucosal gene expression to provide a predictive response signature for infliximab treatment in ulcerative colitis. METHODS: Two cohorts of patients who received their first treatment with infliximab for refractory ulcerative colitis were studied. Response to infliximab was defined as endoscopic and histological healing. Total RNA from pre-treatment colonic mucosal biopsies was analysed with Affymetrix Human Genome U133 Plus 2.0 Arrays. Quantitative RT-PCR was used to confirm microarray data. RESULTS: For predicting response to infliximab treatment, pre-treatment colonic mucosal expression profiles were compared for responders and non-responders. Comparative analysis identified 179 differentially expressed probe sets in cohort A and 361 in cohort B with an overlap of 74 probe sets, representing 53 known genes, between both analyses. Comparative analysis of both cohorts combined, yielded 212 differentially expressed probe sets. The top five differentially expressed genes in a combined analysis of both cohorts were osteoprotegerin, stanniocalcin-1, prostaglandin-endoperoxide synthase 2, interleukin 13 receptor alpha 2 and interleukin 11. All proteins encoded by these genes are involved in the adaptive immune response. These markers separated responders from non-responders with 95% sensitivity and 85% specificity. CONCLUSION: Gene array studies of ulcerative colitis mucosal biopsies identified predictive panels of genes for (non-)response to infliximab. Further study of the pathways involved should allow a better understanding of the mechanisms of resistance to infliximab therapy in ulcerative colitis. ClinicalTrials.gov number, NCT00639821. [less ▲]Detailed reference viewed: 11 (6 ULg)
Cluster analysis of genetic variants enables reclassification of Crohn’s disease at the molecular level
; ; Mahachie John, Jestinah et al
in Gut (2009)Detailed reference viewed: 20 (9 ULg)
Genetics of ulcerative colitis: the come-back of interleukin 10.
Louis, Edouard ; Libioulle, Cécile ; Reenaers, Catherine et al
in Gut (2009), 58(9), 1173-6Detailed reference viewed: 42 (7 ULg)
Effect of infliximab treatment on colonic mucosal gene expression profiles in patients with inflammatory bowel disease
; ; et al
in Gut (2008), 57(Suppl II), 39Detailed reference viewed: 9 (3 ULg)
Gene expression of antimicrobial peptides in colonic mucosa of patients with inflammatory bowel disease before and after first infliximab treatment.
; ; et al
in Gut (2008), 57(Suppl II), 102-103Detailed reference viewed: 10 (3 ULg)
Faecal bacterial molecular profiles of Crohn’s disease patients differ from their healthy relatives and matched healthy controls.
; ; et al
in Gut (2007), 56(Suppl III), 5Detailed reference viewed: 8 (4 ULg)
Mucosal gene expression profiling to predict response to infliximab in patients with ulcerative colitis
; ; Van Steen, Kristel et al
in Gut (2007), 56(Suppl III), 19Detailed reference viewed: 7 (4 ULg)
New serological markers in inflammatory bowel disease are associated with complicated disease behavior
; ; et al
in Gut (2007), 56(10), 1394-1403
OBJECTIVE: The human androgen receptor (AR) contains a polyglutamine and a polyglycine stretch which are highly polymorphic and are coded respectively by a CAG and GGN repeat in exon 1 of the AR gene ... [more ▼]
OBJECTIVE: The human androgen receptor (AR) contains a polyglutamine and a polyglycine stretch which are highly polymorphic and are coded respectively by a CAG and GGN repeat in exon 1 of the AR gene. Although the in vitro studies indicated a possible effect of the GGN repeat polymorphism on the AR gene transcription and clinical observations suggest that it might modulate the androgen action, its functional significance remains unclear. We wanted to assess whether the GGN repeat affects the serum testosterone levels in healthy men, which is the expected outcome through feedback regulation if it influences androgen action as has been shown to be the case for the CAG repeat. DESIGN AND PATIENTS: A population based cross-sectional cohort study including 1476 healthy young, middle-aged, and elderly men. MEASUREMENT: Testosterone and LH levels were determined by immunoassay; free testosterone (FT) levels were calculated. Genotyping of the GGN repeat was performed using the sequencing technique. RESULTS: The GGN repeat number was significantly associated with circulating testosterone and FT levels (P=0.017 and P=0.013 respectively). However, taking into account that age, body mass index, and CAG are already in the regression model, the GGN repeat could explain only a small part of the variation of both testosterone and FT. CONCLUSION: To our knowledge, this study is the first to demonstrate a significant positive association between the GGN repeat and androgen levels in a large cohort of healthy men. Although the present study thus adds credence to the view that the polyglycine tract in the AR can modulate AR action, this effect appears to be only small so that its clinical relevance remains questionable. [less ▲]Detailed reference viewed: 19 (5 ULg)