Herpetiform pemphigus with characteristic transmission electron microscopic findings of various-sized ballooning vacuoles in keratinocytes without acantholysis.

We report a unique case of a Japanese woman with herpetiform pemphigus (HP) who had IgG autoantibodies reactive with nondesmosomal sites of keratinocytes and presented characteristic transmission electron microscopic (TEM) findings of various-sized vacuoles in keratinocytes without acantholysis. The patient presented with pruritic annular oedematous erythemas with small blisters lining the margins on the trunk and extremities. Histopathological examinations showed intraepidermal blisters with prominent infiltrations of eosinophils. Direct and indirect immunofluorescence tests revealed the presence of in vivo bound and circulating IgG autoantibodies to the keratinocyte cell surfaces. However, enzyme-linked immunosorbent assays for desmoglein (Dsg) 1, Dsg3 and desmocollins 1-3 showed negative results. Immunoblotting using the full-length human Dsg1 recombinant protein showed a positive band. TEM examination showed various-sized vacuoles squashing the nuclei in many keratinocytes, resulting in rupture of the cells. Immunoelectron microscopic examination revealed IgG deposition over the entire keratinocyte cell surfaces, which spared the desmosomes. IgG antibodies were also present on the inside walls of the vacuoles around the nuclei of keratinocytes and on the cell surfaces of infiltrating eosinophils. This patient also had marked eosinophilia and high levels of thymus and activation-regulated chemokine and interleukin-5 in the serum. These results indicated a novel autoantigen on the nondesmosomal keratinocyte cell surfaces and the pathogenesis of bullous spongiotic change with inflammation in HP.

Associations of tissue transglutaminase antibody seropositivity with coronary heart disease: Findings from a prospective cohort study.

BACKGROUND AND AIMS: Clinical experience and observational studies suggest that individuals with coeliac disease are at increased risk of coronary heart disease (CHD), but the precise mechanism for this is unclear. Laboratory studies suggest that it may relate to tissue transglutaminase antibodies (tTGAs). Our aim was to examine whether seropositivity for tTGA and endomysial antibodies (EMAs) are associated with incident CHD in humans. METHODS AND RESULTS: We used data from Mini-Finland Health Survey, a prospective cohort study of Finnish men and women aged 35-80 at study baseline 1978-80. TTGA and EMA seropositivities were ascertained from baseline blood samples and incident CHD events were identified from national hospitalisation and death registers. Cox regression was used to examine the associations between antibody seropositivity and incident CHD. Of 6887 men and women, 562 were seropositive for tTGAs and 72 for EMAs. During a median follow-up of 26 years, 2367 individuals experienced a CHD event. We found no clear evidence for an association between tTGA positivity (hazard ratio, HR: 1.04, 95% confidence interval, CI: 0.83, 1.30) or EMA positivity (HR: 1.16, 95% CI: 0.77, 1.74) and incident CHD, once pre-existing CVD and known CHD risk factors had been adjusted for. CONCLUSION: We found no clear evidence for an association of tTGA or EMA seropositivity with incident CHD outcomes, suggesting that tTG autoimmunity is unlikely to be the biological link between coeliac disease and CHD.

Microarray identification of bacterial species in peritonsillar abscesses.

Peritonsillar abscess (PTA) is the most common otorhinolaryngological infection, requiring management at the special healthcare level. The microbiological findings vary due to geographical, etiological, and methodological factors. This study aimed to identify the bacterial species of PTAs by using a novel polymerase chain reaction (PCR)- and microarray-based assay, and to find causative cofactors among patients with different pathogens. We determined the bacterial findings of aspirates of pus prospectively collected from 180 PTA patients. Samples were pretreated prior to nucleic acid extraction and analyzed with a PCR- and microarray-based assay or DNA sequencing. Both methods were based on the gyrB/parE topoisomerase genes. Patients answered symptom questionnaires at admission, and their medical records were reviewed later. Altogether, 160 (89 %) aspirates of pus tested positive for bacteria, and a bacterial species was identified in 149 (83 %) of the samples. A polybacterial species was detected in 20 (13 %) and anaerobic bacteria in 77 (52 %) of the 149 samples. Fusobacterium necrophorum patients were younger (p < 0 .001) and had more severe symptoms (p = 0.04) than patients with other pathogens. Gender, smoking, or preadmission antibiotics showed no correlation with any of the pathogens. Although requiring some optimization, this microarray assay seems feasible and fast for bacterial identification directly from pus samples, and confirms the diversity of PTA pathogens. Young patients with more severe symptoms may require special attention. Species-specific antibiotic treatment of PTA remains challenging due to bacterial variations; the present assay may aid in specifying PTA antibiotic treatment in the future.

Associations of coeliac disease with coronary heart disease and cerebrovascular disease: A systematic review and meta-analysis.

AIMS: Clinical experience suggests that atherosclerotic disease is common in individuals with coeliac disease, but epidemiological studies have had contradicting findings. To summarise the currently available evidence, we systematically reviewed and analysed observational studies of the association of coeliac disease or dermatitis herpetiformis with coronary heart disease (CHD) or stroke. DATA SYNTHESIS: We searched for studies comparing CHD or stroke outcomes with individuals with and without coeliac disease or dermatitis herpetiformis. Three investigators independently searched electronic databases, identified relevant studies and extracted data. Study-specific results were combined in random-effects meta-analyses, and heterogeneity was quantified using the I(2) statistic and meta-regression. Twenty-one studies were included in our systematic review and 18 in the meta-analyses. For CHD, the pooled hazard ratio for incident disease was 1.05 (95% confidence interval (CI): 0.93, 1.19) and the overall standardised mortality ratio was 1.21 (0.99, 1.49). For stroke and brain haemorrhage, the corresponding estimates were 1.10 (95% CI: 1.00, 1.21) and 1.43 (0.97, 2.10), respectively. There was moderate to considerable heterogeneity among the study-specific estimates. In addition, many estimates were based on small numbers of outcomes and they had limitations in terms of adjustment for potential confounders. CONCLUSION: Our meta-analyses lend some support to an association between coeliac disease and CHD or cerebrovascular disease, but the evidence base was heterogeneous and had limitations. Our systematic review highlighted a need in this area for adequately powered prospective studies with appropriate adjustment for potentially confounding factors.

Gliadin antibodies in older population and neurological and psychiatric disorders.

OBJECTIVES: A variety of neurological and psychiatric disorders have recently been linked to coeliac disease and gluten sensitivity. We here explored whether persistently positive gliadin antibodies (AGA) and coeliac-type HLA increase the risk of gluten sensitivity-related neurological and psychiatric manifestations. The study was carried out in an older population who had consumed gluten for decades but who had no previous coeliac disease diagnosis. MATERIALS AND METHODS: The original study population comprised 4272 randomly selected older individuals, of whom 2089 had AGA and transglutaminase 2 antibodies (antiTG2) measured twice within a 3-year interval. Forty-nine persistently AGA-positive but antiTG2-negative subjects with coeliac-type HLA and 52 randomly selected persistently AGA- and antiTG2-negative age- and sex-matched controls were clinically examined for neurological disorders. The Psychological General Well-Being (PGWB) questionnaire, the SF-36 health survey questionnaire and the Depression Scale (DEPS) were employed to evaluate psychological well-being. The medical files of all the study subjects were analysed for previous illnesses. RESULTS: Persistently AGA-positive but antiTG2-negative older subjects carrying coeliac disease-type HLA did not evince significantly more neurological symptoms or diseases than AGA-negative control subjects (P = 0.682, P = 0.233). There were no statistically significant differences between AGA-positive and AGA-negative groups in psychological well-being and quality of life when measured by PGWB (P = 0.426), SF-36 questionnaires (P = 0.120) and DEPS (P = 0.683). CONCLUSIONS: At population level, persistent AGA positivity did not indicate gluten sensitivity-related neurological and psychiatric disorders.

Altered expression of intestinal human leucocyte antigen D-related and immune signalling molecules in juvenile idiopathic arthritis.

We aimed to study intestinal immune activation status in juvenile idiopathic arthritis (JIA) by assessing intestinal human leucocyte antigen (HLA) class II expression and the mRNA expression levels of the pro- and anti-inflammatory mediators and pattern recognition receptors. HLA-D-related (HLA-DR) expression was assessed using immunohistochemical staining of frozen sections in 11 children with JIA and 17 controls. The gene expression levels of the anti- and proinflammatory cytokines, lymphocyte recognition receptors and pattern recognition receptors were studied with reverse transcription-polymerase chain reaction (RT-PCR) in 14 children with JIA and 12 controls. All subjects had various gastrointestinal (GI) symptoms indicating endoscopic examinations, but eventually were not diagnosed with GI disease. In JIA patients, the expression of HLA-DR was increased in the crypt epithelial cells and in the epithelial basement membrane of the ileum when compared with the controls. Positive HLA-DR staining in the ileal mucosa was associated with the presence of high clinical disease activity of JIA and low mRNA expression of anti-inflammatory mediators, such as forkhead box protein P3 (FoxP3), glucocorticoid-induced tumour necrosis factor receptor-related protein (GITR) and transforming growth factor (TGF)-beta. Low ileal expression of interleukin (IL)-10, TGF-ß, FoxP3, Toll-like receptor 2 (TLR-2) and TLR-4 transcripts correlated significantly with a high clinical disease activity in the JIA patients. The increased HLA-DR expression suggests enhanced intestinal antigen presentation in JIA. A correlation between clinical disease activity and low gene expression of tolerogenic mediators in the ileum supports the hypothesis that a link exists between the gut immune system and JIA.

Association study of FUT2 (rs601338) with celiac disease and inflammatory bowel disease in the Finnish population.

Homozygosity for a nonsense mutation in the fucosyltransferase 2 (FUT2) gene (rs601338G>A) leads to the absence of ABH blood groups (FUT2 non-secretor status) in body fluids. As the secretor status has been shown to be a major determinant for the gut microbial spectrum, assumed to be important in the gut immune homeostasis, we studied the association of rs601338-FUT2 with celiac disease (CelD) and inflammatory bowel disease (IBD) in the Finnish population. Rs601338 was genotyped in CelD (n = 909), dermatitis herpetiformis (DH) (n = 116), ulcerative colitis (UC) (n = 496) and Crohn's disease (CD) (n = 280) patients and healthy controls (n = 2738). CelD showed significant genotypic [P = 0.0074, odds ratio (OR): 1.28] and recessive (P = 0.015, OR: 1.28) association with the rs601338-AA genotype. This was also found in the combined CelD+DH dataset (genotype association: P = 0.0060, OR: 1.28; recessive association: P < 0.011, OR: 1.28). The A allele of rs601338 showed nominal association with dominant protection from UC (P = 0.044, OR: 0.82) and UC+CD (P = 0.035, OR: 0.84). The frequency of non-secretors (rs601338-GG) in controls, CelD, DH, UC and CD datasets was 14.7%, 18%, 18.1%, 14.3% and 16.1%, respectively. No association was evident in the DH or CD datasets alone. In conclusion, FUT2 non-secretor status is associated with CelD susceptibility and FUT2 secretor status may also play a role in IBD in the Finnish population.

Coeliac disease diagnosis: ESPGHAN 1990 criteria or need for a change? Results of a questionnaire.

BACKGROUND AND OBJECTIVES: A revision of criteria for diagnosing coeliac disease (CD) is being conducted by The European Society for Pediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN). In parallel, we have performed a survey aimed to evaluate present practices for CD among paediatric gastroenterologists and to learn their views on the need for modification of present criteria for CD diagnosis. PATIENTS AND METHODS: Questionnaires were distributed to experienced paediatric gastroenterologists (ESPGHAN members) via the Internet. RESULTS: Overall, 95 valid questionnaires were available for analysis, pertaining to 28 different countries, with the majority of responders treating patients with CD for >15 years. Only about 12% of the responders comply with present criteria, noncompliance being related mainly to the challenge policy. Approximately 90% request a revision and modification of the present criteria. Forty-four percent want to omit the small bowel biopsy in symptomatic children with positive anti-tissue transglutaminase immunoglobulin (Ig) A or endomysial IgA antibodies, especially if they are DQ2/DQ8 positive. For silent cases detected by screening with convincingly positive anti-tissue transglutaminase IgA or EMA IgA, about 30% consider that no small bowel biopsy should be required in selected cases. Adding human leukocyte antigen typing in the diagnostic workup was asked for by 42% of the responders. As for gluten challenge, a new policy is advocated restricting its obligation to cases whenever the diagnosis is doubtful or unclear. CONCLUSIONS: Based on these opinions, revision of the ESPGHAN criteria for diagnosing CD is urgently needed.

European Society for Pediatric Gastroenterology, Hepatology, and Nutrition guidelines for the diagnosis of coeliac disease.

OBJECTIVE: Diagnostic criteria for coeliac disease (CD) from the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) were published in 1990. Since then, the autoantigen in CD, tissue transglutaminase, has been identified; the perception of CD has changed from that of a rather uncommon enteropathy to a common multiorgan disease strongly dependent on the haplotypes human leukocyte antigen (HLA)-DQ2 and HLA-DQ8; and CD-specific antibody tests have improved. METHODS: A panel of 17 experts defined CD and developed new diagnostic criteria based on the Delphi process. Two groups of patients were defined with different diagnostic approaches to diagnose CD: children with symptoms suggestive of CD (group 1) and asymptomatic children at increased risk for CD (group 2). The 2004 National Institutes of Health/Agency for Healthcare Research and Quality report and a systematic literature search on antibody tests for CD in paediatric patients covering the years 2004 to 2009 was the basis for the evidence-based recommendations on CD-specific antibody testing. RESULTS: In group 1, the diagnosis of CD is based on symptoms, positive serology, and histology that is consistent with CD. If immunoglobulin A anti-tissue transglutaminase type 2 antibody titers are high (>10 times the upper limit of normal), then the option is to diagnose CD without duodenal biopsies by applying a strict protocol with further laboratory tests. In group 2, the diagnosis of CD is based on positive serology and histology. HLA-DQ2 and HLA-DQ8 testing is valuable because CD is unlikely if both haplotypes are negative. CONCLUSIONS: The aim of the new guidelines was to achieve a high diagnostic accuracy and to reduce the burden for patients and their families. The performance of these guidelines in clinical practice should be evaluated prospectively.

Ethical issues of placebo-controlled studies in depression and a randomized withdrawal trial in Japan: case study in the ethics of mental health research.

The use of placebo controls in psychiatric research is controversial. In this article, we focus on a troubling Japanese case of a randomized withdrawal trial of the antidepressant sertraline and analyze the ethical issues underlying it. First, we consider whether a placebo-controlled withdrawal trial should, in general, be considered more ethical than a standard placebo-controlled trial. We argue that the use of a placebo arm in this trial is ethically permissible but that there is no good reason to use a withdrawal trial design. Second, we discuss whether our moral evaluation of the use of placebo in this case should change when the special Japanese regulatory environment is taken into account. We argue that it should not and conclude that the use of withdrawal design in this case is ethically unacceptable.

Cardiac positron emission tomography/computed tomography imaging accurately detects anatomically and functionally significant coronary artery disease.

BACKGROUND: Computed tomography (CT) is increasingly used to detect coronary artery disease, but the evaluation of stenoses is often uncertain. Perfusion imaging has an established role in detecting ischemia and guiding therapy. Hybrid positron emission tomography (PET)/CT allows combination angiography and perfusion imaging in short, quantitative, low-radiation-dose protocols. METHODS AND RESULTS: We enrolled 107 patients with an intermediate (30% to 70%) pretest likelihood of coronary artery disease. All patients underwent PET/CT (quantitative PET with (15)O-water and CT angiography), and the results were compared with the gold standard, invasive angiography, including measurement of fractional flow reserve when appropriate. Although PET and CT angiography alone both demonstrated 97% negative predictive value, CT angiography alone was suboptimal in assessing the severity of stenosis (positive predictive value, 81%). Perfusion imaging alone could not always separate microvascular disease from epicardial stenoses, but hybrid PET/CT significantly improved this accuracy to 98%. The radiation dose of the combined PET and CT protocols was 9.3 mSv (86 patients) with prospective triggering and 21.8 mSv (21 patients) with spiral CT. CONCLUSIONS: Cardiac hybrid PET/CT imaging allows accurate noninvasive detection of coronary artery disease in a symptomatic population. The method is feasible and can be performed routinely with <10 mSv in most patients. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00627172.

Epithelial transport and deamidation of gliadin peptides: a role for coeliac disease patient immunoglobulin A.

In coeliac disease, the intake of dietary gluten induces small-bowel mucosal damage and the production of immunoglobulin (Ig)A class autoantibodies against transglutaminase 2 (TG2). We examined the effect of coeliac patient IgA on the apical-to-basal passage of gluten-derived gliadin peptides p31-43 and p57-68 in intestinal epithelial cells. We demonstrate that coeliac IgA enhances the passage of gliadin peptides, which could be abolished by inhibition of TG2 enzymatic activity. Moreover, we also found that both the apical and the basal cell culture media containing the immunogenic gliadin peptides were able to induce the proliferation of deamidation-dependent coeliac patient-derived T cells even in the absence of exogenous TG2. Our results suggest that coeliac patient IgA could play a role in the transepithelial passage of gliadin peptides, a process during which they might be deamidated.

Genome-wide analysis of extended pedigrees confirms IL2-IL21 linkage and shows additional regions of interest potentially influencing coeliac disease risk.

Coeliac disease is a chronic inflammatory condition of the small intestine, triggered by dietary exposure to gluten in genetically susceptible individuals. Risk alleles at HLA-DQA1 and HLA-DQB1 are necessary for disease development, but are alone not sufficient for disease onset. We aimed to identify novel loci underlying susceptibility to coeliac disease through the use of extended Finnish and Hungarian families with multiple affected individuals. An initial whole-genome linkage approach yielded several loci that were followed up further using the Immunochip custom array. Loci with a parametric logarithm of odds (LOD) score of >1.3 were identified at 4q, 6p [human leukocyte antigen (HLA) region], 6q, 7p, 17p, 17q and at 22p. The 4q and 6q loci have been identified previously in coeliac disease risk, whereas follow-up analyses indicate that the 17p and 22p loci may be novel risk loci for coeliac disease. These loci harbour previously described risk variants for other autoimmune diseases, but their segregation patterns do not explain the linkage to coeliac disease. We followed up the linkage to the 4q region, containing the previously described interleukin (IL)2 and IL21 genes. The risk variants at 4q in the studied pedigrees are most likely distinct from previously described risk variants, indicating that the observed linkage may be due to rare high-risk variants of still unknown nature. The importance of this locus to coeliac disease risk was further shown by the finding that serum levels of IL21 were elevated in both untreated and treated coeliac patients compared to controls.

Mannitol facilitates neurotrophic factor up-regulation and behavioural recovery in neonatal hypoxic-ischaemic rats with human umbilical cord blood grafts.

We recently demonstrated that blood-brain barrier permeabilization using mannitol enhances the therapeutic efficacy of systemically administered human umbilical cord blood (HUCB) by facilitating the entry of neurotrophic factors from the periphery into the adult stroke brain. Here, we examined whether the same blood-brain barrier manipulation approach increases the therapeutic effects of intravenously delivered HUCB in a neonatal hypoxic-ischaemic (HI) injury model. Seven-day-old Sprague-Dawley rats were subjected to unilateral HI injury and then at day 7 after the insult, animals intravenously received vehicle alone, mannitol alone, HUCB cells (15k mononuclear fraction) alone or a combination of mannitol and HUCB cells. Behavioural tests at post-transplantation days 7 and 14 showed that HI animals that received HUCB cells alone or when combined with mannitol were significantly less impaired in motor asymmetry and motor coordination compared with those that received vehicle alone or mannitol alone. Brain tissues from a separate animal cohort from the four treatment conditions were processed for enzyme-linked immunosorbent assay at day 3 post-transplantation, and revealed elevated levels of GDNF, NGF and BDNF in those that received HUCB cells alone or when combined with mannitol compared with those that received vehicle or mannitol alone, with the combined HUCB cells and mannitol exhibiting the most robust neurotropic factor up-regulation. Histological assays revealed only sporadic detection of HUCB cells, suggesting that the trophic factor-mediated mechanism, rather than cell replacement per se, principally contributed to the behavioural improvement. These findings extend the utility of blood-brain barrier permeabilization in facilitating cell therapy for treating neonatal HI injury.

Transplanted long-term cultured pre-BI cells expressing calpastatin are resistant to B cell receptor-induced apoptosis.

Long-term cultured pre-B cells are able to differentiate into immunoglobulin (Ig)M-positive B cells (IgM(+) cells) when transplanted into severe combined immunodeficient (SCID) mice. Based on previous studies, here we report the development of a reconstitution assay in nonobese diabetic/SCID (NOD/SCID) mice using pre-B cells, which allows us to study the role of calpains (calcium-activated endopeptidases) during B cell development as well as in B cell clonal deletion. Using this model, we show that calpastatin (the natural inhibitor of calpains) inhibits B cell receptor-induced apoptosis in IgM(+) cells derived from transplanted mice. We thus hypothesize an important function for calpain in sculpting the B cell repertoire.

Degradation of coeliac disease-inducing rye secalin by germinating cereal enzymes: diminishing toxic effects in intestinal epithelial cells.

Currently the only treatment for coeliac disease is a lifelong gluten-free diet excluding food products containing wheat, rye and barley. There is, however, only scarce evidence as to harmful effects of rye in coeliac disease. To confirm the assumption that rye should be excluded from the coeliac patient's diet, we now sought to establish whether rye secalin activates toxic reactions in vitro in intestinal epithelial cell models as extensively as wheat gliadin. Further, we investigated the efficacy of germinating cereal enzymes from oat, wheat and barley to hydrolyse secalin into short fragments and whether secalin-induced harmful effects can be reduced by such pretreatment. In the current study, secalin elicited toxic reactions in intestinal Caco-2 epithelial cells similarly to gliadin: it induced epithelial cell layer permeability, tight junctional protein occludin and ZO-1 distortion and actin reorganization. In high-performance liquid chromatography and mass spectroscopy (HPLC-MS), germinating barley enzymes provided the most efficient degradation of secalin and gliadin peptides and was thus selected for further in vitro analysis. After germinating barley enzyme pretreatment, all toxic reactions induced by secalin were ameliorated. We conclude that germinating enzymes from barley are particularly efficient in the degradation of rye secalin. In future, these enzymes might be utilized as a novel medical treatment for coeliac disease or in food processing in order to develop high-quality coeliac-safe food products.

Malignancies in cases with screening-identified evidence of coeliac disease: a long-term population-based cohort study.

BACKGROUND AND AIMS: The association between diagnosed coeliac disease and malignancy has been established. The present study was conducted to determine whether previously unrecognised and thus untreated adults with screening-identified evidence of coeliac disease carry an increased risk of malignancies. METHODS: A Finnish population-based adult-representative cohort of 8000 individuals was drawn in 1978-1980. Stored sera of the participants with no history of coeliac disease or any malignancy were tested for immunoglobulin A (IgA) class tissue transglutaminase antibodies (Eu-tTG) in 2001. Positive sera were further analysed by another tissue transglutaminase antibody test (Celikey tTG) and for endomysial antibodies (EMAs). Malignant diseases were extracted from the nationwide database and antibody-positive cases were compared with negative cases during a follow-up of nearly 20 years. RESULTS: Altogether 565 of all the 6849 analysed serum samples drawn in 1978-80 were Eu-tTG positive. In further analyses, 202 (2.9%) of the participants were Celikey tTG positive and 73 (1.1%) were EMA positive. The overall risk of malignancy was not increased among antibody-positive cases in the follow-up of two decades; the age- and sex-adjusted relative risk was 0.91 (95% CI 0.60 to 1.37) for those who were Celikey tTG positive and 0.67 (95% CI 0.28 to 1.61) for those who were EMA positive. CONCLUSIONS: The prognosis of adults with unrecognised coeliac disease with positive coeliac disease antibody status is good as regards the overall risk of malignancies. Thus, current diagnostic practice is sufficient and there is no need for earlier diagnosis of coeliac disease by mass screening on the basis of the findings of this study.

The shared CTLA4-ICOS risk locus in celiac disease, IgA deficiency and common variable immunodeficiency.

IgA deficiency (IgAD) and common variable immunodeficiency (CVID) often co-occur in families, associating with chronic inflammatory diseases such as celiac disease (CD). ICOS (inducible co-stimulator) and CTLA4 (cytotoxic T-lymphocyte-associated protein-4) may be important in both disorders, as ICOS is necessary for Ig class-switching and CTLA4 negatively regulates T-cell activation. Linkage and association of CD with CTLA4-ICOS is well documented, we thus aimed to further pinpoint CD susceptibility by haplotype-tagging analysis. We genotyped 663 CD families from Finland and Hungary, 575 additional CD patients from Finland, Hungary and Italy; 275 Swedish and Finnish IgAD individuals and 87 CVID individuals for 14-18 genetic markers in CTLA4-ICOS. Association was found between CTLA4-ICOS and both IgAD (P=0.0015) and CVID (P=0.0064). We confirmed linkage of CTLA4-ICOS with CD (LOD 2.38, P=0.0005) and found association of CTLA4-ICOS with CD (P=0.0009). Meta-analysis of the IgAD, CVID and CD materials revealed intergenic association (P=0.0005). Disease-associated markers were associated with lower ICOS and higher CTLA4 expression, indicating that the risk haplotypes contain functional variants. In summary, we identified a novel shared risk locus for IgAD, CVID and CD, the first report of association between CTLA4-ICOS and IgAD. Association between CD and CTLA4-ICOS was also confirmed in a large European data set.

Fine mapping of the CELIAC2 locus on chromosome 5q31-q33 in the Finnish and Hungarian populations.

Celiac disease is a chronic inflammation of the small intestine, arising in genetically predisposed individuals as a result of ingestion of dietary gluten. The only confirmed and functionally characterised genetic risk factors for celiac disease are the DQ2 or DQ8 heterodimers at the major histocompatibility complex (MHC) class II locus (CELIAC1). These genes are necessary but alone not sufficient for disease onset. Genome-wide linkage scans have suggested chromosome 5q31-q33 (CELIAC2) as an important risk locus for celiac disease. This region has also been associated to other inflammatory disorders, although as yet, no clear gene associations have been found. In the current study, 11 celiac disease candidate loci were screened for genetic linkage in the Hungarian population. As the CELIAC2 locus showed the strongest evidence for linkage, this locus was selected for follow-up. Seventeen candidate genes were selected from the CELIAC2 locus, and genotyped using 48 haplotype tagging single nucleotide polymorphisms (SNPs) in large Finnish and Hungarian family materials. A subset of these, 40 tagging SNPs in 15 genes, were genotyped in an independent set of Finnish and Hungarian cases and controls. We confirmed linkage of this region with celiac disease and report strong linkage in both the Finnish and Hungarian populations. The association analysis showed modest associations throughout the whole region. These association findings were not replicated in the case-control datasets. Our study strongly supports the role of the CELIAC2 locus in celiac disease, but it also highlights the need for a more powerful study design in the region, to locate the true disease risk variants.

Linkage and association study of FcgammaR polymorphisms in celiac disease.

The Fcgamma receptor cluster on chromosome 1q23 contains a number of genes that may affect susceptibility to celiac disease, but previous studies have yielded contradictory results. We studied the FcgammaRIIa*A519G (rs1801274) and FcgammaRIIIa*A559C (rs396991) single nucleotide polymorphisms in celiac disease families from Hungary and Finland and in celiac disease case-control materials from Hungary and Italy. Neither the Hungarian nor the Italian case-control material or a meta-analysis of the combined case-control material showed significant single-marker or haplotype association. In addition, neither linkage nor family-based association tests showed evidence for association in the Finnish or Hungarian family material. This study thus does not support a previous publication showing FcgammaR association with celiac disease.