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1.
Hand Surg ; 17(1): 143-4, 2012.
Article in English | MEDLINE | ID: mdl-22351554

ABSTRACT

Four-corner fusion is an accepted surgical treatment for established SLAC and SNAC wrist. We describe a technique of bone grafting to be used in conjunction with any of the standard fusion techniques. A step by step, illustrated approach allows the easy placement of an autograft which is in contact with all surfaces of the bones involved in the fusion.


Subject(s)
Arthrodesis/methods , Bone Transplantation/methods , Carpal Bones/surgery , Wrist Joint/surgery , Humans
2.
Hand Surg ; 16(3): 301-5, 2011.
Article in English | MEDLINE | ID: mdl-22072464

ABSTRACT

Trapezio-metacarpal joint arthritis is common, affecting 7% of men and 15% of women. Numerous surgical techniques are described for this condition but it is not clear which is best. Eighty-six silicone trapezium replacements were assessed at an average of 46 months (six to 156 months) postoperatively for patient satisfaction, pain, key and power grip strength, range of motion, complications and disability with DASH score. Patient satisfaction was 92%. There was excellent pain reduction from 4.2 to 0.6 on a scale of 0 to 5. Strength was 72% and 84% of age-sex-matched normal data for key and power grips, respectively. The complication rate was low, with two cases of persistent pain. One resolved spontaneously, the other resolved following revision of the silicone implant. The average DASH score was 30. Silicone trapezium replacement is an effective operation that offers the patient good pain relief, strength and good function with few complications.


Subject(s)
Arthroplasty, Replacement/methods , Joint Prosthesis , Metacarpophalangeal Joint/surgery , Osteoarthritis/surgery , Patient Satisfaction , Trapezium Bone/surgery , Aged , Aged, 80 and over , Female , Follow-Up Studies , Humans , Male , Metacarpophalangeal Joint/diagnostic imaging , Metacarpophalangeal Joint/physiopathology , Middle Aged , Osteoarthritis/diagnostic imaging , Osteoarthritis/physiopathology , Pain Measurement , Radiography , Range of Motion, Articular , Retrospective Studies , Time Factors , Trapezium Bone/diagnostic imaging , Treatment Outcome
3.
Tissue Antigens ; 77(1): 23-9, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20887385

ABSTRACT

Previous linkage studies have identified a region at 1p36 as the susceptibility locus (IBD7) of inflammatory bowel disease (IBD). The objective of this study was to investigate whether polymorphisms of caspase-9 (CASP9) gene and RUNX3 are associated with IBD susceptibility and clinical phenotypes. We studied 555 Crohn's disease (CD) and 651 ulcerative colitis (UC) patients recruited from a single UK center. A total of 964 healthy Caucasian subjects were recruited as controls from general practitioner well person clinics in Oxfordshire. Fourteen single nucleotide polymorphisms (SNPs) of CASP9 and 11 SNPs of RUNX3 were genotyped using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) (homogenous MassEXTEND, hME, Sequenom™, Sequenom Inc., San Diego, CA). Linkage disequilibrium (LD) and haplotype association analysis were performed using 2ld and phase v2.0 software. No association of individual SNPs of CASP9 or RUNX3 with UC or CD was identified. The rs1052571 of CASP9 was associated with severe UC [P = 0.0034, odds ratio (OR) = 1.957, 95% confidence interval (CI) = 1.240-3.088]. Significant haplotype associations between CASP9 and IBD were identified, while no association of RUNX3 haplotypes with either UC or CD was found. Our findings suggested that CASP9 gene might be another IBD susceptibility gene.


Subject(s)
Caspase 9/genetics , Core Binding Factor Alpha 3 Subunit/genetics , Genetic Predisposition to Disease , Inflammatory Bowel Diseases/genetics , Adult , Female , Humans , Male , United Kingdom , White People/genetics
4.
Tissue Antigens ; 76(1): 48-56, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20403135

ABSTRACT

The first Crohn's disease (CD) susceptibility gene identified was CARD15, which is a member of the emerging NOD-like receptor (NLR) family. These function as intracellular cystosolic pattern recognition receptors (PRRs) and play a central role in the innate immune response. We studied other members of the NLR family using a gene-wide haplotype tagging approach in a well-characterised collection of 547 CD patients and 465 controls. Four single nucleotide polymorphisms (SNPs) in NLRP3 had P values < 0.05 and are in high linkage disequilibrium (LD) with each other (r(2) > 0.90 for all four SNPs). rs4925648 and rs10925019 were the most strongly associated with CD susceptibility (P = 0.001, odds ratio (OR) 1.62, 95% CI 1.2-2.18; and P = 6.5 x 10(-4), OR 1.65, 95% CI 1.23-2.19, respectively). rs1363758 located in NLRP11 was associated with CD susceptibility [P = 0.002 (1.64, 1.19-2.25)], which was weakly confirmed in an independent case-cohort collection on joint analysis [P = 0.05, (1.28, 1-1.64)]. On sub-phenotype analysis, an interesting association between NLRP1 and skin extra-intestinal manifestations and colonic, inflammatory CD was identified. None of these results was replicated in the Wellcome Trust Case Control Consortium study and therefore need replication in a further large cohort.


Subject(s)
Crohn Disease/genetics , Nod Signaling Adaptor Proteins/genetics , Adolescent , Adult , Female , Genetic Predisposition to Disease , Genome-Wide Association Study , Genotype , Humans , Male , Phenotype , Polymorphism, Single Nucleotide
5.
Tissue Antigens ; 74(4): 322-9, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19659809

ABSTRACT

Linkage in families and association in population case-control investigations have clearly shown that genes within the major histocompatibility complex region on chromosome 6p are relevant to the susceptibility and pathogenesis of ulcerative colitis (UC) and Crohn's disease. However, identifying the causative variants by fine mapping has not been conclusive. In this study using 58 single nucleotide polymorphisms (SNPs) with 616 UC cases, there was significant association with SNP rs2294881 of the (butyrophilin-like 2) BTNL2 gene with odds ratio (OR) = 2.80, confidence interval (CI) = 1.62-4.84 and P = 5.69 x 10(-4) (P(Bonferroni) = 3.3 x 10(-2)) and replication of SNP rs9268480. The missense SNP rs2076523 (K196E) showed novel association with a subset of UC cases with colectomy (n = 126), OR = 0.25, CI = 0.11-0.58 and P = 4.42 x 10(-4) (P(Bonferroni) = 2.56 x 10(-2)). These three associated variants within the BTNL2 gene were neither in linkage disequilibrium with each other nor correlated with the SNPs tagging the human leukocyte antigen (HLA)-DRB1*1502 and HLA-DRB1*0301 alleles.


Subject(s)
Colitis, Ulcerative/genetics , Haplotypes/genetics , Membrane Glycoproteins/genetics , Polymorphism, Single Nucleotide/genetics , Butyrophilins , Case-Control Studies , Cohort Studies , Colectomy , Colitis, Ulcerative/pathology , Colitis, Ulcerative/surgery , Female , Genome-Wide Association Study , Genotype , HLA-DR Antigens/classification , HLA-DR Antigens/genetics , HLA-DRB1 Chains , Humans , Linkage Disequilibrium , Male , Polymerase Chain Reaction
6.
Mucosal Immunol ; 2(3): 220-31, 2009 May.
Article in English | MEDLINE | ID: mdl-19262505

ABSTRACT

The MEP1A gene, located on human chromosome 6p (mouse chromosome 17) in a susceptibility region for inflammatory bowel disease (IBD), encodes the alpha-subunit of metalloproteinase meprin A, which is expressed in the intestinal epithelium. This study shows a genetic association of MEP1A with IBD in a cohort of ulcerative colitis (UC) patients. There were four single-nucleotide polymorphisms in the coding region (P=0.0012-0.04), and one in the 3'-untranslated region (P=2 x 10(-7)) that displayed associations with UC. Moreover, meprin-alpha mRNA was decreased in inflamed mucosa of IBD patients. Meprin-alpha knockout mice exhibited a more severe intestinal injury and inflammation than their wild-type counterparts following oral administration of dextran sulfate sodium. Collectively, the data implicate MEP1A as a UC susceptibility gene and indicate that decreased meprin-alpha expression is associated with intestinal inflammation in IBD patients and in a mouse experimental model of IBD.


Subject(s)
Genetic Predisposition to Disease , Inflammatory Bowel Diseases/genetics , Metalloendopeptidases/genetics , Alleles , Animals , Colitis, Ulcerative/genetics , Colitis, Ulcerative/metabolism , Colitis, Ulcerative/pathology , Dextran Sulfate , Humans , Inflammatory Bowel Diseases/chemically induced , Inflammatory Bowel Diseases/metabolism , Inflammatory Bowel Diseases/pathology , Metalloendopeptidases/metabolism , Mice , Mice, Knockout , Polymorphism, Single Nucleotide , RNA, Messenger/metabolism
7.
Inflamm Bowel Dis ; 15(6): 823-8, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19145641

ABSTRACT

BACKGROUND: To determine the long-term outcome of patients admitted with acute severe colitis (ASC) who avoided colectomy on the index admission, a retrospective cohort study was performed. METHODS: Patients admitted for intensive treatment of ASC in 1992-1993 previously described for a predictive index of short-term outcome in severe ulcerative colitis (UC) were followed for a median 122 months (range 3-144). Complete responders (CR) to intensive therapy had <3 nonbloody stools/day on day 7 of the index admission; incomplete responders (IR) were all others who avoided colectomy on that admission. Main outcome measures were colectomy-free survival, time to colectomy, and duration of steroid-free remission. RESULTS: In all, 6/19 CR (32%) came to colectomy compared to 10/13 IR (P = 0.016; relative risk 3.33, 95% confidence interval [CI] 1.12-9.9). The median +/- interquartile range time to colectomy was 28 +/- 47 months (range 6-99) for CR who came to colectomy versus 7.5 +/- 32 (3-72) months for IR (P = 0.118). Among the IR, 7/13 came to colectomy within 12 months, and all within 6 years from the index admission. The longest period of steroid-free remission was 42 +/- 48 (0-120) months for CR, but 9 +/- 20 (1-35) months for IR (P = 0.011). CONCLUSIONS: One week after admission with ASC in the prebiologic era, IRs had a 50% chance of colectomy within a year and 70% within 5 years, despite cyclosporin and azathioprine where appropriate. The maximum duration of remission in CRs was almost 5 times longer than IRs. It is unknown whether biologics change the long-term outcome.


Subject(s)
Colectomy/statistics & numerical data , Colitis, Ulcerative , Hospitalization/statistics & numerical data , Immunosuppressive Agents/therapeutic use , Adult , Azathioprine/therapeutic use , Cohort Studies , Colitis, Ulcerative/drug therapy , Colitis, Ulcerative/epidemiology , Colitis, Ulcerative/surgery , Cost of Illness , Cyclosporine/therapeutic use , England/epidemiology , Follow-Up Studies , Humans , Kaplan-Meier Estimate , Middle Aged , Predictive Value of Tests , Remission Induction , Retrospective Studies , Risk Factors , Severity of Illness Index , Steroids/therapeutic use , Time Factors
8.
Aliment Pharmacol Ther ; 29(2): 193-7, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18945256

ABSTRACT

BACKGROUND: Sacroiliitis is a recognized complication of Crohn's disease and may occur distinct from progressive ankylosing spondylitis (AS). AIM: To estimate prospectively the prevalence of sacroiliitis in patients with established Crohn's disease, to characterize the clinical features and to correlate these with the presence of HLA-B27. METHODS: All Crohn's disease patients under active follow-up of between 5 and 12 years duration were invited to participate. Patients underwent a clinical evaluation including symptom questionnaire, rheumatological examination and underwent HLA genotyping. Patients then underwent magnetic resonance imaging (MRI) of the sacroiliac joints. The clinical and radiological factors were correlated with HLA-B27 status. RESULTS: 56 patients underwent initial assessment and 44 had MRI scans. Seventeen of 44 (39%) patients had MRI evidence of sacroiliitis, of whom 5 fulfilled the criteria for AS. Symptoms of low back pain were elicited in a majority of these patients--11/17 (65%) compared to 3 of 27 (11%) patients with normal scans (P = 0.003). There were no differences in functional indices with the exception of patients with AS. HLA-B27 was present in seven patients, and all seven had MRI evidence of sacroiliitis, five had AS. CONCLUSIONS: Sacroiliitis is common in patients with established Crohn's disease and in the majority of cases, patients have symptoms of inflammatory low back pain if questioned carefully. HLA-B27 is not associated with isolated sacroiliitis, but is associated with AS. However, possession of HLA-B27 appears to convey a very high risk of developing axial inflammation in Crohn's disease.


Subject(s)
Crohn Disease/complications , HLA-B27 Antigen , Low Back Pain/etiology , Sacroiliitis/etiology , Adult , Crohn Disease/immunology , Crohn Disease/physiopathology , Female , Follow-Up Studies , HLA-B27 Antigen/immunology , Humans , Low Back Pain/immunology , Low Back Pain/physiopathology , Male , Prevalence , Risk Factors , Sacroiliac Joint , Sacroiliitis/immunology , Sacroiliitis/physiopathology , Spondylitis/immunology , Time Factors
9.
Trans R Soc Trop Med Hyg ; 102(9): 857-60, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18455744

ABSTRACT

Inflammatory bowel disease (IBD) is increasing in many countries 'beyond the West'. This increase may be due to an increased rate of diagnosis but might also represent a true increase in incidence. Economic development, leading to improved hygiene and other changes in lifestyle, may play a role in the increase in IBD. However, the marked difference in prevalence between ethnic groups suggests that the genetic background of populations may also be relevant and supports the current hypothesis that IBD represents an interaction between environmental factors and a genetically susceptible host. Investigating the early stages of IBD as it emerges in new populations may provide new clues to its pathophysiology.


Subject(s)
Hygiene , Inflammatory Bowel Diseases/epidemiology , Humans , Incidence , Inflammatory Bowel Diseases/economics , Inflammatory Bowel Diseases/etiology , Prevalence , Socioeconomic Factors
10.
Aliment Pharmacol Ther ; 25(9): 1055-60, 2007 May 01.
Article in English | MEDLINE | ID: mdl-17439506

ABSTRACT

BACKGROUND: Infliximab has been shown to be of benefit in the treatment of ulcerative colitis but long-term colectomy rates remain unknown. AIMS: To review the rate of colectomy after infliximab for ulcerative colitis and to identify factors that might predict the need for colectomy. METHODS: We conducted a retrospective cohort study of patients with active ulcerative colitis treated with infliximab between 2000 and 2006. The primary outcome was colectomy-free survival. Disease and treatment characteristics and complications were documented. RESULTS: Thirty patients were treated with infliximab for refractory ulcerative colitis. Sixteen (53%) came to colectomy a median of 140 days after their first infusion (range 4-607). There was no difference in colectomy between those receiving infliximab for acute severe ulcerative colitis failing intravenous steroids (8/14) and out-patients with steroid-refractory ulcerative colitis (8/16). Only 17% (5/30) achieved a steroid-free remission after a median follow-up of 13 months (range 2-72). Univariate analysis showed that a younger age at diagnosis of colitis was significantly associated with an increased rate of colectomy (27.5 years vs. 38.7 years, P = 0.016). CONCLUSION: Over half the patients studied came to colectomy. Of those avoiding colectomy, only five (17%) sustained a steroid-free remission.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Colectomy/statistics & numerical data , Colitis, Ulcerative/drug therapy , Gastrointestinal Agents/therapeutic use , Cohort Studies , Colitis, Ulcerative/surgery , Disease-Free Survival , Female , Humans , Infliximab , Male , Middle Aged , Retrospective Studies , Treatment Outcome
11.
Aliment Pharmacol Ther ; 24(10): 1403-12, 2006 Nov 15.
Article in English | MEDLINE | ID: mdl-17081161

ABSTRACT

BACKGROUND: More than half of the patients with inflammatory bowel diseases are candidates for immunosuppressive therapy. However, even the most effective drugs used in inflammatory bowel disease are only successful in about two-thirds of patients. Adverse events limit their use in a further substantial proportion of patients. Recent research has focussed on the possibility of predicting a drugs' efficacy and/or toxicity by identifying polymorphic variants in the genes encoding enzymes involved in metabolic pathways. AIM: To highlight recent advances and limitations in the field of pharmacogenetics in inflammatory bowel disease. RESULTS: Recent pharmacogenetic studies have mainly focussed on immunosuppressive agents including corticosteroids, azathioprine, methotrexate and infliximab. Several polymorphic genes encoding enzymes involved in the metabolism of these drugs have been identified including the inosine triphosphate pyrophosphatase in thiopurine therapy, the methylene tetrahydrofolate reductase in methotrexate therapy and polymorphisms in apoptosis genes in infliximab therapy. However, at the present time, genotyping for the variants of the thiopurine methyltransferase gene, an enzyme important for the metabolism of the thiopurine drugs, is the only useful test in clinical practice. CONCLUSIONS: Although the field of pharmacogenetics in inflammatory bowel disease is promising most new targets have so far failed to translate into clinical practice. Future pharmaceutical trials should include pharmacogenetic research to test appropriate candidate genes in a prospective manner.


Subject(s)
Anti-Inflammatory Agents/therapeutic use , Genetic Predisposition to Disease , Immunosuppressive Agents/therapeutic use , Inflammatory Bowel Diseases/drug therapy , Steroids/therapeutic use , Humans , Inflammatory Bowel Diseases/genetics , Pharmacogenetics
12.
Tissue Antigens ; 68(4): 325-30, 2006 Oct.
Article in English | MEDLINE | ID: mdl-17026468

ABSTRACT

Idiopathic bronchiectasis is a disease of chronic, bacterial lung infection, unresolving inflammation and progressive lung damage. Bronchiectasis can be associated with autoimmune diseases including ulcerative colitis. Defects of both innate and adaptive immunity have been proposed. The airway inflammation is characterized by interleukin-8 (IL-8) expression and infiltration by neutrophils and T cells. Here we investigated two candidate gene polymorphisms that may contribute to disease susceptibility: a CXCR-1 (+2607 G/C) gene polymorphism that is implicated in IL-8 binding and neutrophil trafficking as well as the interferon-gamma (IFNgamma) (+874 T/A) polymorphism which is linked to levels of IFNgamma production. These polymorphisms were distributed similarly in the idiopathic bronchiectasis group and controls, suggesting that these two candidate gene polymorphisms are not associated with disease susceptibility.


Subject(s)
Bronchiectasis/genetics , Bronchiectasis/immunology , Interferon-gamma/genetics , Polymorphism, Single Nucleotide , Receptors, Interleukin-8A/genetics , Alleles , Colitis, Ulcerative/genetics , Colitis, Ulcerative/immunology , Female , Genetic Predisposition to Disease , Genotype , Humans , Male , Middle Aged
13.
Genes Immun ; 7(7): 576-82, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16929347

ABSTRACT

Killer immunoglobulin-like receptors (KIRs) are expressed on natural killer cells and some T-cell subsets and produce either activation or inhibitory signals upon binding with the appropriate human leucocyte antigen (HLA) ligand on target cells. Recent genetic association studies have implicated KIR genotype in the development of several inflammatory conditions. Ulcerative colitis (UC) is an inflammatory disorder of the colonic mucosa that results from an inappropriate activation of the immune system driven by host bacterial flora. We developed a polymerase chain reaction-sequence specific primer (SSP)-based assay to genotype 194 UC patients and 216 control individuals for 14 KIR genes, the HLA-Cw ligand epitopes of the KIR2D receptors and a polymorphism of the lectin-like-activating receptor NKG2D. Initial analysis found the phenotype frequency of KIR2DL2 and -2DS2 to be significantly increased in the UC cohort (P=0.030 and 0.038, respectively). Logistic regression analysis revealed a protective effect conferred by KIR2DL3 in the presence of its ligand HLA-Cw group 1 (P=0.019). These results suggest that KIR genotype and HLA ligand interaction may contribute to the genetic susceptibility of UC.


Subject(s)
Colitis, Ulcerative/genetics , Colitis, Ulcerative/immunology , HLA Antigens/genetics , Receptors, Immunologic/genetics , Base Sequence , Case-Control Studies , DNA Primers/genetics , Gene Frequency , Genotype , HLA-C Antigens/genetics , Humans , Killer Cells, Natural/immunology , Ligands , Multigene Family , NK Cell Lectin-Like Receptor Subfamily K , Phenotype , Polymorphism, Single Nucleotide , Receptors, KIR , Receptors, KIR2DL2 , Receptors, KIR2DL3 , Receptors, Natural Killer Cell
15.
Br J Surg ; 93(4): 475-82, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16502479

ABSTRACT

BACKGROUND: Strictureplasty is an effective means of alleviating obstructive Crohn's disease while conserving bowel length. The aim of this study was to establish long-term outcomes of strictureplasty. METHODS: Between 1978 and 2003, 479 strictureplasties were performed in 100 patients during 159 operations. Information on Crohn's disease, medical therapy, laboratory indices, surgical details, complication rates and outcomes was recorded. The primary endpoint was abdominal reoperation. RESULTS: Mean follow-up was 85.1 (range 0.2-240.9) months. The overall morbidity rate was 22.6 per cent, with septic complications in 11.3 per cent, obstruction in 4.4 per cent and gastrointestinal haemorrhage in 3.8 per cent. The 30-day mortality rate was 0.6 per cent and the procedure-related series mortality rate 3.0 per cent. Perioperative parenteral nutrition was the only marker for morbidity (P < 0.001). Reoperation rates were 52 per cent at a mean of 40.2 (range 0.2-205.8) months after a first, 56 per cent at 26.1 (range 3.5-63.5) months after a second, 86 per cent at 27.4 (range 1.4-74.5) months after a third, and 62.5 per cent at 25.9 (range 7.3-70.5) months following a fourth strictureplasty procedure. The major risk factor for reoperation was young age (P < 0.001). CONCLUSION: Long-term follow-up has confirmed the safety of strictureplasty in Crohn's disease. Morbidity is appreciable, although the surgical mortality rate is low. Reoperation rates are comparable following first and repeat strictureplasty procedures.


Subject(s)
Crohn Disease/surgery , Ileal Diseases/surgery , Intestinal Obstruction/surgery , Postoperative Complications/etiology , Adolescent , Adult , Aged , Crohn Disease/complications , Female , Follow-Up Studies , Humans , Ileal Diseases/etiology , Intestinal Obstruction/etiology , Male , Middle Aged , Reoperation/statistics & numerical data , Retrospective Studies , Risk Factors , Suture Techniques
16.
Gut ; 55(7): 969-72, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16423886

ABSTRACT

BACKGROUND AND AIMS: Development of coeliac disease involves an interaction between environmental factors (especially dietary wheat, rye, and barley antigens) and genetic factors (there is strong inherited disease susceptibility). The known human leucocyte antigen (HLA)-DQ2 and -DQ8 association explains only a minority of disease heritability. A recent study in the Dutch population suggested that genetic variation in the 3' region of myosin IXB (MYO9B) predisposes to coeliac disease. MYO9B is a Rho family GTPase activating protein involved in epithelial cell cytoskeletal organisation. MYO9B is hypothesised to influence intestinal permeability and hence intestinal antigen presentation. METHODS: Four single nucleotide polymorphisms were chosen to tag all common haplotypes of the MYO9B 3' haplotype block (exons 15-27). We genotyped 375 coeliac disease cases and 1366 controls (371 healthy and 995 population based). All individuals were of White UK Caucasian ethnicity. RESULTS: UK healthy control and population control allele frequencies were similar for all MYO9B variants. Case control analysis showed no significant association of any variant or haplotype with coeliac disease. CONCLUSIONS: Genetic variation in MYO9B does not have a major effect on coeliac disease susceptibility in the UK population. Differences between populations, a weaker effect size than originally described, or possibly a type I error in the Dutch study might explain these findings.


Subject(s)
Celiac Disease/genetics , Myosins/genetics , Polymorphism, Single Nucleotide , Adolescent , Adult , Aged , Aged, 80 and over , Case-Control Studies , Chi-Square Distribution , Child , Child, Preschool , Female , Gene Frequency , Genetic Predisposition to Disease , Haplotypes , Humans , Male , Middle Aged , United Kingdom
17.
Gut ; 55(4): 485-91, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16299041

ABSTRACT

BACKGROUND: Coeliac disease (CD) is due to an inappropriate T cell mediated response to specific gluten peptides. Measured by interferon gamma (IFN-gamma) ELISPOT, about half of the gliadin specific T cells induced with in vivo wheat gluten exposure in HLA-DQ2+ CD are specific for an alpha/beta-gliadin peptide (p57-73 QE65; QLQPFPQPELPYPQPQS) that includes two overlapping T cell epitopes (PFPQPELPY and PQPELPYPQ). AIM: To define minimally substituted variants of p57-73 QE65 universally devoid of IFN-gamma stimulatory capacity but capable of antagonising IFN-gamma secretion from polyclonal T cells specific for p57-73 QE65. METHODS: Peripheral blood mononuclear cells collected from 75 HLA-DQ2+ CD patients after in vivo gluten challenge were used in overnight ELISPOT assays to screen 218 single or double substituted variants of p57-73 QE65 for cytokine stimulatory and antagonist activity. RESULTS: The region p60-71 (PFPQPELPYPQP) and especially p64-67 (PELP) was sensitive to substitution. Twelve substitutions in p64-67 stimulated no IFN-gamma ELISPOT response. Among 131 partial agonists identified, 45 produced statistically significant inhibition of IFN-gamma ELISPOT responses when cocultured in fivefold excess with p57-73 QE65 (n = 10). Four substituted variants of p57-73 QE65 were inactive by IFN-gamma ELISPOT but consistently antagonised IFN-gamma ELISPOT responses to p57-73 QE65, and also retained interleukin 10 stimulatory capacity similar to p57-73 QE65. CONCLUSIONS: Altered peptide ligands of p57-73 QE65, identified using polyclonal T cells from multiple HLA-DQ2+ CD donors, have properties in vitro that suggest that a single substitution to certain alpha/beta-gliadins could abolish their capacity to stimulate IFN-gamma from CD4 T cells and also have anti-inflammatory or protective effects in HLA-DQ2+ CD.


Subject(s)
Celiac Disease/immunology , Epitopes, T-Lymphocyte/immunology , Gliadin/immunology , Interferon-gamma/metabolism , Peptide Fragments/immunology , Triticum/immunology , Adult , Aged , Amino Acids/immunology , Cells, Cultured , Cytokines/immunology , Enzyme-Linked Immunosorbent Assay/methods , Female , Gliadin/antagonists & inhibitors , Humans , Interferon-gamma/immunology , Leukocytes, Mononuclear/immunology , Male , Middle Aged , T-Lymphocytes/immunology
18.
Scand J Rheumatol ; 34(3): 233-7, 2005.
Article in English | MEDLINE | ID: mdl-16134731

ABSTRACT

BACKGROUND: Behçet's disease (BD) is a chronic multi-system inflammatory disorder of unknown aetiology, which shares many features of the inflammatory bowel diseases (IBDs). CARD15 has recently been identified as the first susceptibility gene in Crohn's disease (CD). OBJECTIVE: Given certain clinical and pathological similarities between CD and BD, and recent evidence of linkage of BD to the CARD15 genomic region, the aim of this study was to investigate the role of CARD15 variants in determining susceptibility to BD. METHODS: We studied 374 BD patients from three ethnically homogeneous cohorts (white English, Turkish, and Middle Eastern Arabs of Palestinian and Jordanian descent). Mutation detection of CARD15 was performed by direct sequencing in a subset of patients from each group and the identified variants were genotyped in the complete cohorts. Case-control analyses were carried out with additional stratification by the BD-associated allele, HLA-B*51. RESULTS: Mutation detection identified six previously described CARD15 polymorphisms at a frequency of > 3%. Additionally, two of the three CD-associated polymorphisms were present, but at low frequency. The frequency of haplotypes, constructed from nine genotyped polymorphisms, demonstrated significant variation between different ethnic groups. However, case-control analyses demonstrated no association between the CARD15 polymorphisms and susceptibility to BD, irrespective of HLA-B*51 status. CONCLUSION: CARD15 variant alleles are not associated with susceptibility to BD. Other shared loci, currently under investigation, may determine susceptibility to both CD and BD.


Subject(s)
Behcet Syndrome/genetics , Genetic Predisposition to Disease , Intracellular Signaling Peptides and Proteins/genetics , Polymorphism, Genetic , Arabs/ethnology , Behcet Syndrome/ethnology , Case-Control Studies , DNA Mutational Analysis , England/ethnology , Genotype , HLA-B Antigens/genetics , HLA-B51 Antigen , Humans , Jordan/ethnology , Nod2 Signaling Adaptor Protein , Turkey/ethnology , White People/ethnology
19.
Gut ; 54(9): 1217-23, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16099789

ABSTRACT

BACKGROUND: Current understanding of T cell epitopes in coeliac disease (CD) largely derives from intestinal T cell clones in vitro. T cell clones allow identification of gluten peptides that stimulate T cells but do not quantify their contribution to the overall gluten specific T cell response in individuals with CD when exposed to gluten in vivo. AIMS: To determine the contribution of a putative dominant T cell epitope to the overall gliadin T cell response in HLA-DQ2 CD in vivo. PATIENTS: HLA-DQ2+ individuals with CD and healthy controls. METHODS: Subjects consumed 20 g of gluten daily for three days. Interferon gamma (IFN-gamma) ELISPOT was performed using peripheral blood mononuclear cells (PBMC) to enumerate and characterise peptide and gliadin specific T cells before and after gluten challenge. RESULTS: In 50/59 CD subjects, irrespective of homo- or heterozygosity for HLA-DQ2, IFN-gamma ELISPOT responses for an optimal concentration of A-gliadin 57-73 Q-E65 were between 10 and 1500 per million PBMC, equivalent to a median 51% of the response for a "near optimal" concentration of deamidated gliadin. Whole deamidated gliadin and gliadin epitope specific T cells induced in peripheral blood expressed an intestinal homing integrin (alpha4beta7) and were HLA-DQ2 restricted. Peripheral blood T cells specific for A-gliadin 57-73 Q-E65 are rare in untreated CD but can be predictably induced two weeks after gluten exclusion. CONCLUSION: In vivo gluten challenge is a simple safe method that allows relevant T cells to be analysed and quantified in peripheral blood by ELISPOT, and should permit comprehensive high throughput mapping of gluten T cell epitopes in large numbers of individuals with CD.


Subject(s)
Antigens , Celiac Disease/immunology , Glutens , T-Lymphocytes/immunology , Adult , Aged , Case-Control Studies , Enzyme-Linked Immunosorbent Assay/methods , Epitopes, T-Lymphocyte , Female , Gliadin/immunology , HLA-DQ Antigens/analysis , Humans , Immunity, Cellular , Immunophenotyping , Integrins/analysis , Interferon-gamma/immunology , Intestinal Mucosa/immunology , Lymphocyte Activation , Male , Middle Aged , Peptide Fragments , Sensitivity and Specificity , Statistics, Nonparametric
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