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1.
Sci Rep ; 5: 12955, 2015 Aug 12.
Article in English | MEDLINE | ID: mdl-26264409

ABSTRACT

Faecal microbiota transplantation (FMT) is effective in the treatment of Clostridium difficile infection, where efficacy correlates with changes in microbiota diversity and composition. The effects of FMT on recipient microbiota in inflammatory bowel diseases (IBD) remain unclear. We assessed the effects of FMT on microbiota composition and function, mucosal immune response, and clinical outcome in patients with chronic pouchitis. Eight patients with chronic pouchitis (current PDAI ≥7) were treated with FMT via nasogastric administration. Clinical activity was assessed before and four weeks following FMT. Faecal coliform antibiotic sensitivities were analysed, and changes in pouch faecal and mucosal microbiota assessed by 16S rRNA gene pyrosequencing and (1)H NMR spectroscopy. Lamina propria dendritic cell phenotype and cytokine profiles were assessed by flow cytometric analysis and multiplex assay. Following FMT, there were variable shifts in faecal and mucosal microbiota composition and, in some patients, changes in proportional abundance of species suggestive of a "healthier" pouch microbiota. However, there were no significant FMT-induced metabolic or immunological changes, or beneficial clinical response. Given the lack of clinical response following FMT via a single nasogastric administration our results suggest that FMT/bacteriotherapy for pouchitis patients requires further optimisation.


Subject(s)
Fecal Microbiota Transplantation , Pouchitis/therapy , Adult , Chronic Disease , Female , Humans , Immunity, Innate , Male , Metabolomics , Middle Aged , Pouchitis/immunology , Pouchitis/metabolism , Pouchitis/microbiology , Proton Magnetic Resonance Spectroscopy
3.
J Crohns Colitis ; 7(6): 460-6, 2013 07.
Article in English | MEDLINE | ID: mdl-22857825

ABSTRACT

BACKGROUND: Treatment resistant chronic pouchitis causes significant morbidity. Elemental diet is effective treatment for Crohn's disease. Since pouchitis shares some similarities to Crohn's disease we hypothesised that elemental diet may be an effective treatment. METHOD: Seven pouchitis patients (with ulcerative colitis) were studied. All had active pouchitis with a pouch disease activity index (PDAI) ≥7. Exclusion criteria were recent NSAIDs, antibiotics or probiotics. Sufficient elemental diet to achieve energy requirements was provided. Flexible-pouchoscopy was performed, and the Cleveland Global Quality of Life score (CGQoL), Pouch Disease Activity Index (PDAI) and BMI were recorded at baseline and following 28 days of elemental diet. Faecal samples were also collected at these time points and analysed for major bacterial groups using culture independent fluorescence in situ hybridisation. Data were analysed using Wilcoxon's signed-rank test. RESULTS: Following 28 days of exclusive elemental diet, median stool frequency decreased from 12 to 6 per day (p=0.028), median clinical PDAI decreased from 4 to 1 (p=0.039). There was no significant difference in quality of life scores or PDAI before and following treatment. There was a trend towards an increase in the concentration of Clostridium coccoides-Eubacterium rectale (median 7.9 to 8.5 log10/g, p=0.08) following exclusive elemental diet. CONCLUSION: Treatment with four weeks elemental diet appeared to improve the symptoms of chronic pouchitis in some patients but is not an effective strategy for inducing remission. Although a potential symptom modifier, elemental diet cannot be recommended for the routine treatment of active pouchitis.


Subject(s)
Feces/microbiology , Food, Formulated , Pouchitis/diet therapy , Adult , Chronic Disease , Clostridium/isolation & purification , Endoscopy, Gastrointestinal , Eubacterium/isolation & purification , Female , Humans , In Situ Hybridization, Fluorescence , Male , Middle Aged , Oligonucleotide Probes , Prospective Studies , Quality of Life
4.
Inflamm Bowel Dis ; 18(6): 1146-55, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22021180

ABSTRACT

Restorative proctocolectomy with ileal-pouch anal anastomosis (RPC) is the operation of choice for ulcerative colitis (UC) patients requiring surgery. It is also used for patients with familial adenomatous polyposis (FAP). Pouchitis accounts for 10% of pouch failures. It is an idiopathic inflammatory condition that may occur in up to 50% of patients after RPC for UC. It is rarely seen in FAP patients after RPC. The etiology of pouchitis remains unclear. An overlap with UC is suggested by the frequency with which pouchitis affects patients with UC compared with FAP patients. There is significant clinical evidence implicating bacteria in the pathogenesis of pouchitis. Studies using culture and molecular methods demonstrate a dysbiosis of the pouch microbiota in pouchitis. Risk factors, genetic associations, and serological markers of pouchitis suggest that the interactions between the host immune responses and the pouch microbiota underlie the etiology of this idiopathic inflammatory condition. Here we present a detailed review of the data focusing on the pouch microbiota and the immune responses that support this hypothesis. We also discuss the contribution of luminal metabolic factors and the epithelial membrane in the etiology of this inflammatory process. The ileoanal pouch offers a unique opportunity to study the inter-relationships between the gut microbiota and host immune responses from before the onset of disease. For this reason the study of pouchitis could serve as a human model that significantly enhances our understanding of inflammatory bowel diseases in general.


Subject(s)
Inflammatory Bowel Diseases/surgery , Pouchitis/etiology , Proctocolectomy, Restorative/adverse effects , Humans , Risk Factors
5.
Aliment Pharmacol Ther ; 34(4): 409-15, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21682755

ABSTRACT

BACKGROUND: Evidence is emerging regarding the relationship between a dysbiosis of the human gut microbiota and a number of gastrointestinal diseases as well as diseases beyond the gut. Probiotics have been investigated in many gastrointestinal disease states, with variable and often modest outcomes. Faecal transplantation is an alternative approach to manipulate the gut microbiota. AIM: To review the use of faecal transplantation therapy for the management of gastrointestinal disorders. METHODS: Available articles on faecal transplantation in the management of gastrointestinal disorders were identified using a Pubmed search and bibliographies of review articles on the subject were collated. RESULTS: A total of 239 patients who had undergone faecal transplantation were reported. Seventeen of 22 studies of faecal transplantation were in fulminant or refractory Clostridium difficile. Studies of faecal transplantation are heterogeneous regarding the patients, donors, screening, methods of administration and definition of response. Faecal transplantation for C. difficile has been demonstrated to be effective in 145/166 (87%) patients. Small numbers of patients are reported to have undergone successful faecal transplantation for irritable bowel syndrome and inflammatory bowel disease. CONCLUSIONS: Faecal transplantation has been reported with good outcomes for fulminant and refractory C. difficile. No adverse effects of faecal transplantation have been reported. However, there are no level 1 data of faecal transplantation and reports to date may suffer from reporting bias of positive outcomes and under-reporting of adverse effects. This therapy holds great promise, where a dysbiosis of the gut microbiota is responsible for disease and further studies are necessary to explore this potential.


Subject(s)
Feces/microbiology , Gastrointestinal Diseases/therapy , Gastrointestinal Tract/microbiology , Microbial Interactions , Bacterial Physiological Phenomena , Humans
7.
Colorectal Dis ; 13(4): 438-44, 2011 Apr.
Article in English | MEDLINE | ID: mdl-20041929

ABSTRACT

AIM: About 5% of restorative proctocolectomy (RPC) patients develop chronic antibiotic-dependent pouchitis. These require antibiotic maintenance therapy. We report our experience in managing this patient group. METHOD: Patients with RPC that was treated with antibiotic maintenance therapy were identified from the hospital pouch database. Data including faecal antibiotic sensitivity, functional outcome, side effects and Cleveland Global Quality of Life (CGQOL) score were recorded. RESULTS: Twenty-five patients were identified. The median length of treatment was 15.8 (range 3-62) months. Ten (40%) patients had pouchitis with co-existing prepouch ileitis. The median frequency of defecation was 7 (range 4-11)/24 h, the median clinical Pouch Disease Activity Index (PDAI) was 0 (range 0-1) and the CQGOL score was 0.7 (range 0.5-1.0). Of those who relapsed, three (50%) patients had achieved mucosal healing following the induction of remission. Failure of mucosal healing did not predict a reduced time to relapse (P = 0.18). Prepouch ileitis was associated with an increased risk of developing antibiotic resistance (P = 0.023). Treatment of this with alternating antibiotic combination therapy was successful in all cases. CONCLUSION: Antibiotic maintenance therapy appears safe, well-tolerated and effective for the treatment of chronic antibiotic-dependent pouchitis. It results in an improved quality of life and function. Prepouch ileitis, but not failure of mucosal healing, is associated with an increased risk of developing antibiotic resistance.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Pouchitis/drug therapy , Adult , Amoxicillin-Potassium Clavulanate Combination/administration & dosage , Amoxicillin-Potassium Clavulanate Combination/therapeutic use , Anti-Bacterial Agents/administration & dosage , Cefixime/administration & dosage , Cefixime/therapeutic use , Colistin/administration & dosage , Colistin/therapeutic use , Defecation , Drug Resistance, Bacterial , Drug Therapy, Combination , Female , Humans , Male , Middle Aged , Nitrofurantoin/administration & dosage , Nitrofurantoin/therapeutic use , Pouchitis/complications , Pouchitis/psychology , Proctocolectomy, Restorative , Quality of Life , Recurrence , Remission Induction , Retrospective Studies , Severity of Illness Index , Treatment Outcome , Trimethoprim/administration & dosage , Trimethoprim/therapeutic use
8.
Therap Adv Gastroenterol ; 3(6): 335-48, 2010 Nov.
Article in English | MEDLINE | ID: mdl-21180613

ABSTRACT

Restorative proctocolectomy (RPC) with ileal pouch-anal anastomosis is the operation of choice for patients with ulcerative colitis. Pouchitis is the most common cause of pouch dysfunction. Although the pathogenesis of this disease is not well understood, bacteria have been implicated in the disease process. Numerous bacterial studies have been reported over the last 25 years with few unifying findings. In addition, many different treatments for pouchitis have been reported with varying results. Antibiotic treatment remains the most studied and is the mainstay of treatment. In this article we review the aetiology of pouchitis and the evidenced-based treatment options.

9.
Aliment Pharmacol Ther ; 32(5): 664-9, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20626734

ABSTRACT

BACKGROUND: Treatment with fluoroquinolones is associated with the development of Clostridium difficile and extended spectrum beta-lactamase-producing bacteria (ESBL). Clostridium difficile and ESBL are resistant to many antibiotics and each may cause pouchitis after restorative proctocolectomy (RPC) refractory to empirical antibiotic therapy. AIM: To assess the prevalence and establish risk factors for the development of ESBL and Clostridium difficile toxins (CDT) in RPC patients with recurrent or refractory pouchitis under follow-up at our institution over a 1-year period. METHOD: An enzyme-linked immunosorbent assay was used to detect CDT and a culture technique was used to identity ESBL in faecal samples. All patients had previously received fluoroquinolone treatment. RESULTS: Forty-eight patients (35 (74%) men; median age 42 years) underwent testing at a median interval from RPC of 8 (range 1-25) years. No patient had a positive CDT result, but ESBL bacteria were identified in 16 (33%) samples. ESBL positivity was significantly related to prepouch ileitis (P = 0.035) and maintenance antibiotic therapy (P = 0.039). CONCLUSIONS: Extended spectrum beta-lactamase, but not CDT, is a common finding in faecal samples from patients with recurrent or refractory pouchitis. Treatment with maintenance antibiotics and prepouch ileitis are risk factors for developing ESBL-producing bacteria.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Clostridium Infections/microbiology , Enterobacteriaceae Infections/microbiology , Pouchitis/microbiology , Proctocolectomy, Restorative/adverse effects , beta-Lactamases/metabolism , Adult , Clostridioides difficile/isolation & purification , Drug Resistance , Enterobacteriaceae/isolation & purification , Female , Follow-Up Studies , Humans , Male , Microbial Sensitivity Tests , Middle Aged , Risk Factors , Young Adult
10.
Histopathology ; 54(7): 783-95, 2009 Jun.
Article in English | MEDLINE | ID: mdl-18700844

ABSTRACT

Coeliac disease (CD) is an immune-mediated disease of the small intestine caused by intolerance to gluten. Removal of gluten from the diet results in a return to normal health for the majority of patients. A significant proportion of patients do not respond to a gluten-free diet and are considered to be suffering from refractory coeliac disease (RCD). Two types of RCD are now recognized: type 1 RCD is characterized by a polyclonal population of intraepithelial lymphocytes (IELs) with a normal immunophenotype, and type 2 RCD shows monoclonal IELs with an aberrant immunoprofile. Patients with RCD have a high risk of complications such as ulcerative jejunitis (UJ) and enteropathy-type T-cell lymphoma (ETTL). RCD2 may represent an early stage in the development of overt lymphoma. The diagnosis of RCD, therefore, has important implications, but remains a challenging area. In this paper we review the latest developments in RCD, including the diagnostic approach and a discussion of the key clinical, histological, immunohistochemical and molecular features of RCD and its complications.


Subject(s)
Celiac Disease/diagnosis , Celiac Disease/complications , Celiac Disease/immunology , Celiac Disease/therapy , Diet, Gluten-Free , Enteritis/etiology , Gastrointestinal Neoplasms/etiology , Humans , Jejunal Diseases/etiology , Lymphoma, Non-Hodgkin/etiology , Lymphoma, T-Cell/etiology
11.
Aliment Pharmacol Ther ; 29(1): 69-74, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18945262

ABSTRACT

BACKGROUND: Pre-pouch ileitis is a recently described condition which may occur following restorative proctocolectomy. Its aetiology remains unknown and only one study has reported the effect of treatment. We report a series of fourteen patients treated and followed up with repeat pouchoscopy. AIM: To study the effectiveness of antibiotics for the treatment of pre-pouch ileitis following restorative proctocolectomy with ileal pouch-anal anastomosis. METHODS: Fourteen consecutive patients with symptomatic pre-pouch ileitis were treated with ciprofloxacin 500 mg b.d. and metronidazole 400 mg b.d. for 28 days. All had concurrent pouchitis. Symptomatic, endoscopic and histological assessment was performed before and following treatment using the pouchitis disease activity index (PDAI). Symptomatic remission was defined as a score of 0 in the clinical component of the PDAI. RESULTS: Twelve (86%) patients experienced symptomatic remission. Stool frequency fell from a median of 12 (range 8-20) to 6 (4-17) (P = 0.002). There was a significant reduction in the anatomical length of pre-pouch ileitis with nine (64%) patients having either a resolution or a reduction in length of pre-pouch ileitis from a median of 10 cm (range 3-20 cm) to a median of 1 cm (range 0-10 cm) (P = 0.007). CONCLUSION: Combination antibiotic therapy in this uncontrolled study appears effective in reducing the length of pre-pouch ileitis and in inducing symptomatic remission in most patients whether or not its extent is reduced.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Ciprofloxacin/therapeutic use , Metronidazole/therapeutic use , Pouchitis/drug therapy , Proctocolectomy, Restorative/adverse effects , Adult , Anal Canal/surgery , Anastomosis, Surgical/adverse effects , Female , Humans , Ileum/surgery , Male , Middle Aged , Severity of Illness Index , Statistics as Topic , Treatment Outcome , Young Adult
12.
Dig Dis Sci ; 54(6): 1280-3, 2009 Jun.
Article in English | MEDLINE | ID: mdl-18975089

ABSTRACT

This study compares video capsule endoscopy (VCE) with histological specimens of proximal small bowel in patients with celiac disease who have failed to respond to a gluten-free diet. Patients with nonresponsive celiac disease underwent capsule endoscopy, and concordance between endoscopy and histology was then calculated using the kappa statistic. In 19 patients, endoscopy videos were reported as normal in ten (53%) case, as having mild changes in three (16%) cases, and as having moderate-severe changes in six (31%) cases. Two (11%) had acute ulcers. No small bowel tumors were seen. Endoscopy demonstrated concordance with histological changes in 14 of the 18 patients with histology available (78% concordance). The kappa statistic suggested a substantial degree of concordance between histology and endoscopic findings. Endoscopy with distal duodenal biopsies is superior to VCE in detecting proximal, nonresponsive celiac disease, but more distal lesions may be missed such that the strength of VCE lies in its ability to visualize the entire small bowel.


Subject(s)
Biopsy , Capsule Endoscopy , Celiac Disease/diet therapy , Celiac Disease/pathology , Diet, Gluten-Free , Adult , Aged , Aged, 80 and over , Female , Glutens/adverse effects , Humans , Male , Middle Aged , Pilot Projects , Sensitivity and Specificity , Young Adult
13.
Aliment Pharmacol Ther ; 27(10): 895-909, 2008 May.
Article in English | MEDLINE | ID: mdl-18266993

ABSTRACT

BACKGROUND: Restorative proctocolectomy with ileal pouch-anal anastomosis is the procedure of choice for the majority of patients with ulcerative colitis who require surgery. Over 2500 patients in the UK have undergone restorative proctocolectomy. It is now increasingly being performed in district general hospitals as well as in specialist inflammatory bowel disease units. Gastroenterologists are increasingly involved in the management of patients following restorative proctocolectomy. AIM: To provide gastroenterologists with a clear understanding of the investigation and evidence-based management of complications and the aftercare required in patients who have undergone restorative proctocolectomy. RESULTS: Following restorative proctocolectomy, most patients have an excellent long-term functional outcome. Pouchitis, pelvic sepsis and poor function are the most common causes of failure. The development of cancer is rare; nevertheless, long-term follow-up is required. CONCLUSIONS: The investigation and management of patients who develop complications require a multidisciplinary team approach to optimize the outcome. Protocols are suggested for investigation and management of patients with complications and for long-term cancer surveillance.


Subject(s)
Adenomatous Polyposis Coli/surgery , Colitis, Ulcerative/surgery , Colonic Pouches , Proctocolectomy, Restorative/methods , Colonic Pouches/adverse effects , Defecation , Female , Follow-Up Studies , Humans , Male , Patient Satisfaction , Postoperative Complications/etiology , Pouchitis/etiology , Proctocolectomy, Restorative/adverse effects , Proctocolectomy, Restorative/rehabilitation , Prognosis , Treatment Outcome
14.
Aliment Pharmacol Ther ; 26(6): 963-4; author reply 964, 2007 Sep 15.
Article in English | MEDLINE | ID: mdl-17767481
16.
Colorectal Dis ; 8(5): 402-10, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16684084

ABSTRACT

OBJECTIVE: Ileal inflammation in ulcerative colitis can occur as backwash ileitis or prestomal ileitis. After restorative proctocolectomy (RPC), ileal inflammation may be present in the pouch (pouchitis) but inflammation proximal to the pouch in the neo-terminal ileum, so called pre-pouch ileitis (PI), has also been observed. As pouchitis is increasingly common and PI can mimic it, our aim was to characterize this condition. SUBJECTS AND METHODS: A review of prospectively collected data on 571 inflammatory bowel disease patients undergoing follow-up after RPC in a single centre over 22 years was performed. The histology of biopsy material was reviewed and staining for colonic mucosal phenotypic changes was undertaken. It was not routine practice to prospectively assess all patients for pre-pouch ileitis when the database was constructed. RESULTS: Of 19 patients with inflammation of the pre-pouch neo-terminal ileum (NTI) identified three had Crohn's disease and one a NSAID stricture. The remaining 15 had a characteristic diffuse inflammation extending from the NTI-pouch junction proximally: pre-pouch ileitis. The inflammation extended proximally for up to 50 cm. Fistula formation was seen in only one. Seven (47%) of 15 had pouchitis but only two had suffered backwash ileitis pre-operatively. Seven responded to medical therapy and four to surgery. The histological appearances including staining for colonic phenotypic change were similar in PI and pouchitis. CONCLUSION: Pre-pouch ileitis is uncommon. As the patients' previous diagnosis of UC was confirmed and there was no radiological or histological evidence of Crohn's disease, PI appears to have a distinct pathogenesis from Crohn's disease.


Subject(s)
Colitis, Ulcerative/surgery , Ileitis/diagnosis , Proctocolectomy, Restorative , Adolescent , Adult , Cohort Studies , Colitis, Ulcerative/complications , Colon/chemistry , Colon/pathology , Crohn Disease/complications , Crohn Disease/pathology , Endoscopy, Gastrointestinal , Female , Histocytochemistry , Humans , Ileitis/etiology , Ileitis/therapy , Ileum/chemistry , Ileum/pathology , Male , Middle Aged , Pouchitis/metabolism , Pouchitis/pathology , Prevalence , Sialomucins/analysis , Treatment Outcome
17.
Gut ; 53(12): 1801-5, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15542518

ABSTRACT

BACKGROUND/AIMS: The gut flora may play an important role in the pathogenesis of inflammatory bowel disease. An ileal reservoir or pouch can be created to replace the excised rectum after proctocolectomy. In patients with ulcerative colitis this is subject to inflammation and termed pouchitis. Using bacteria from patients the authors sought evidence for the presence rather than the identity of a pathogenic species in pouchitis, and for its absence in healthy pouches by the differential effect on lymphocyte proliferation. METHODS: An ex vivo cell culture assay was used in which peripheral blood mononuclear cells or lamina propria mononuclear cells were cultured with sterile sonicates of gut flora from patients with or without pouchitis in the presence of antigen presenting cells. RESULTS: Sonicated pouchitis flora produced a consistent and intense proliferation of the mononuclear cells but that produced by sonicates from healthy pouches was minimal (p = 0.012 or 0.018, peripheral blood or lamina propria mononuclear cells). Preparation of the sonicates with the antibiotic metronidazole abolished their stimulatory ability (p = 0.005, peripheral blood mononuclear cells). In separate assays neither direct addition of metronidazole nor of its hydroxy metabolite affected the mononuclear cells' proliferation with alternative stimuli. CONCLUSIONS: These results strongly support a bacterial aetiology for pouchitis.


Subject(s)
Bacteria/pathogenicity , Colonic Pouches/microbiology , Lymphocyte Activation , Metronidazole/pharmacology , Pouchitis/microbiology , Adolescent , Adult , Aged , Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Bacteria/growth & development , Cell Division/drug effects , Cells, Cultured , Female , Humans , Lymphocyte Activation/drug effects , Male , Middle Aged , Sonication
18.
Tissue Antigens ; 63(3): 212-22, 2004 Mar.
Article in English | MEDLINE | ID: mdl-14989710

ABSTRACT

Chromosome region 2q33 harbours a cluster of genes, CTLA-4, CD28, ICOS and closely located PD-1, all related to immune activation and considered as promising candidate genes for susceptibility to coeliac disease (CD). We present here the results of a genetic linkage and association analysis of nine markers located in this gene region in a large combined European material of 796 families with CD from Finland, Sweden, Norway, UK, France and Italy. The joint analysis supports earlier findings that this susceptibility locus, assigned as CELIAC3, merits further studies. Nominally significant linkage to CD was found in 314 families including affected sib pairs. Each of the five populations showed weak associations to several marker alleles, but the analysis revealed, however, no conclusive evidence for a primary functional gene or gene variant present in the total set of families. The results suggest that the CD risk due to 2q33 gene region is complex and may involve more than one susceptibility allele, which possibly differ from other autoimmune diseases.


Subject(s)
Antigens, Differentiation, T-Lymphocyte/genetics , Antigens, Differentiation/genetics , Antigens, Surface/genetics , CD28 Antigens/genetics , Celiac Disease/genetics , Chromosomes, Human, Pair 2/genetics , Alleles , Antigens, CD , Apoptosis Regulatory Proteins , CTLA-4 Antigen , Chromosome Mapping , Europe , Female , Gene Frequency , Genetic Linkage , Genetic Markers , Genetic Predisposition to Disease , Haplotypes/genetics , Humans , Inducible T-Cell Co-Stimulator Protein , Male , Polymorphism, Genetic , Programmed Cell Death 1 Receptor , White People/genetics
19.
Eur J Immunogenet ; 30(6): 427-32, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14675397

ABSTRACT

Coeliac disease (CD) is an immune-mediated enteropathy triggered by gluten in genetically predisposed individuals. Patients with CD have an increased prevalence of other autoimmune disorders, including type 1 diabetes (T1D) and Graves' disease (GD). CD shares with these conditions certain HLA susceptibility alleles. A number of studies have also shown association of autoimmune diseases, including CD, with the CD28-cytotoxic T lymphocyte antigen 4 (CTLA4)-inducible costimulator (ICOS) region of chromosome 2q33, but until recently the precise causal variant has remained unknown. Recently, it was shown that, in GD, CT60 (+6230G>A), a single nucleotide polymorphism (SNP) at the end of the CTLA4 transcript, is associated with an alteration in the ratio of splice forms of the CTLA4 gene and that this ratio affects disease susceptibility. A similar but weaker association was found with T1D. There is also an independent association of GD and T1D with the SNP MH30 (-23 327G>C), which possibly affects promoter region function. Hypothesizing that CT60 and MH30 may be causal variants in other autoimmune disorders, we investigated these SNPs in CD using 149 family trios and 100 unrelated/unaffected controls. No association was detected with either SNP using both the transmission disequilibrium test (TDT) and case-control methods. Our study appears to have good power to detect moderate genetic effects, but possibly these SNPs exert too weak an effect on risk of CD to have been detected in our sample. Alternatively, the previously noted association of CD with the CTLA4 gene region may be due to different causal variants. Unlike T1D and GD, CD is not a true autoimmune disease, and CD has different associations at the CTLA4 exon 1 SNP +49G>A from all other autoimmune disorders. MH30, CT60, and other SNPs in the region may still warrant further investigation in other CD samples.


Subject(s)
Antigens, Differentiation/genetics , Celiac Disease/genetics , Polymorphism, Single Nucleotide , Antigens, CD , CTLA-4 Antigen , Case-Control Studies , Female , Genetic Markers , Genetic Predisposition to Disease , Genetic Variation , HLA-DQ Antigens/genetics , Humans , Male
20.
Gut ; 52(12): 1698-702, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14633945

ABSTRACT

BACKGROUND: Peptides from alpha-gliadins have been used to characterise the immunodominant coeliac toxic epitope. A peptide corresponding to amino acid residues 57-73 of A-gliadin causes peripheral blood mononuclear cells from coeliac patients to secrete interferon gamma (IFN-gamma); gluten specific small intestinal T cell clones proliferate in response to peptides corresponding to residues 57-68 and 62-75 of alpha-gliadins. We wished to investigate whether a peptide corresponding to residues 56-75 of alpha-gliadins exacerbates coeliac disease in vivo. METHODS: Four adults with coeliac disease, all of whom were on a gluten free diet, underwent three challenges. Peptic-tryptic gliadin (PTG 1 g) served as a positive control. The test peptide and a negative control peptide were studied on separate occasions. The peptides were instilled into the duodenum and biopsies were taken before the infusion, and two, four, and six hours after commencing the infusions, using a Quinton hydraulic multiple biopsy capsule. Biopsy specimens were assessed blindly for villus height to crypt depth ratio (VH:CD), enterocyte cell height (ECH), and intraepithelial lymphocyte (IEL) count. We used the Mann-Whitney U test, with 95% confidence intervals, for statistical analysis. RESULTS: VH:CD and ECH fell, and IEL increased significantly 4-6 hours after commencing infusions with both PTG and the test peptide in all subjects. The negative control peptide caused no significant changes to villus morphology, enterocyte height, or IEL count in any patient. CONCLUSION: We have confirmed that the putative immunodominant epitope, a peptide corresponding to residues 56-75 of alpha-gliadins, exacerbates coeliac disease in vivo.


Subject(s)
Celiac Disease/pathology , Gliadin/toxicity , Intestine, Small/pathology , Aged , Biopsy, Needle , Celiac Disease/immunology , Gliadin/immunology , Humans , Immunohistochemistry , Intestine, Small/immunology , Male , Peptide Fragments/immunology , Peptide Fragments/toxicity
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