ABSTRACT
OBJECTIVES: To assess the usefulness of a new class of antibodies, the anti-deamidated gliadin peptides, in the diagnostic approach to children less than 2 years with suspected celiac disease. PATIENTS AND METHODS: We investigated 40 children (median age: 16.8 months; age range: 4-24 months), with symptoms and signs of chronic enteropathy and high serum levels of conventional anti-gliadin antibodies, but normal values of anti-transglutaminase and anti-endomysial antibodies; all underwent measurement of anti-deamidated gliadin peptides serum levels, upper gastrointestinal endoscopy with biopsies and HLA typing; 40 subjects served as controls. RESULTS: In 29 patients (group A) serum levels of anti-deamidated gliadin peptides were normal and duodenal histology showed a spectrum of abnormalities ranging from mucosal inflammatory infiltrates to villous damage (in almost all cases compatible with Marsh 1-to-2 lesions). All improved on a cow's and soy milk free diet containing gluten. In 11 patients (group B) there were high serum levels of anti-deamidated gliadin peptides and histology showed features suggestive of celiac disease (Marsh 2-to-3 lesions) in all; furthermore, human leucocyte antigen typing was consistent with a celiac disease genetic pattern in all. Group B patients significantly improved on a gluten free diet containing cow's and soy milk proteins. None of the control group was anti-deamidated gliadin peptides positive. CONCLUSIONS: In children younger than 2 years with signs of chronic enteropathy and normal values of classical serum markers of celiac disease, the latter can be predicted by high serum levels of anti-deamidated gliadin peptides.
Subject(s)
Celiac Disease/diagnosis , Diarrhea/etiology , Gliadin/immunology , Immunoglobulin A/blood , Immunoglobulin G/blood , Biomarkers/blood , Case-Control Studies , Celiac Disease/diet therapy , Celiac Disease/immunology , Child, Preschool , Chronic Disease , Diagnosis, Differential , Female , Humans , Infant , Male , Peptide Fragments/immunologyABSTRACT
BACKGROUND: Celiac Disease (CD) is an autoimmune disorder of the small intestine in which dietary gluten ingestion leads to a chronic enteropathy. Recently, scientific evidence suggested a potential role of gut microbiota in CD. To have a snapshot of dominant duodenal microbiota we analyzed the mucosa-associated microbiota of 20 children with CD, before and after a gluten-free diet (GFD) regimen, and of 10 controls. Total DNA was extracted from duodenal biopsies and amplification products of 16S ribosomal DNA were compared by temporal temperature gradient gel electrophoresis (TTGE). TTGE profiles were analyzed by statistical multivariate analysis. RESULTS: The average number of bands in TTGE profiles was significantly higher (P < 0.0001) in active (n.b. 16.7 +/- 0.7) and inactive states (n.b. 13.2 +/- 0.8) than in controls (n.b. 3.7 +/- 1.3). Mean interindividual similarity index was 54.9% +/- 14.9% for active disease, 55.6% +/- 15.7% for remission state and 21.8% +/- 30.16% for controls. Similarity index between celiac children before and after GFD treatment was 63.9% +/- 15.8%. Differences in microbiota biodiversity were among active and remission state (P = 0.000224) and amid active CD and controls (P < 0.001). Bacteroides vulgatus and Escherichia coli were detected more often in CD patients than in controls (P < 0.0001). CONCLUSIONS: Overall, the results highlighted a peculiar microbial TTGE profile and a significant higher biodiversity in CD pediatric patients' duodenal mucosa. The possible pathophysiological role of these microbial differences needs further characterization.
Subject(s)
Bacteria/isolation & purification , Celiac Disease/microbiology , Adolescent , Bacteria/classification , Bacteria/genetics , Biodiversity , Celiac Disease/diet therapy , Child , Child, Preschool , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , Diet, Gluten-Free , Female , Humans , Infant , Intestinal Mucosa/microbiology , Male , Molecular Sequence Data , Phylogeny , RNA, Ribosomal, 16S/genetics , Young AdultABSTRACT
BACKGROUND: NOD2 is an intracellular protein involved in host recognition of specific bacterial molecules and is genetically associated with several inflammatory diseases, including Crohn's disease (CD). NOD2 stimulation activates the transcription factor, NF-kappaB, through RIP2, a caspase-recruitment domain-containing kinase. NOD2/RIP2 signaling also mediates the activation of antimicrobial peptides such as human alpha-defensin 5 (HD-5) and human alpha-defensin 6 (HD-6), both produced by Paneth cells. The present study is aimed at describing the downstream events triggered specifically by NOD2 induction in order to demonstrate that the protein, other than overexpressed, is also physiologically associated with RIP2 and Erbin in the bioptic intestinal inflamed specimens of children affected by CD. METHODS: Fifteen children with CD and 10 children used as controls were entered in the study. Mucosal biopsy specimens were taken during endoscopy and mRNA and protein expressions were detected by using real-time polymerase chain reaction and Western blot. RESULTS: NOD2 is able to form an immunocomplex with the kinase RIP2. As compared to controls, in the inflamed mucosa of patients both mRNA and protein expression levels of RIP2 are increased, and its active phosphorylated form is overexpressed. CONCLUSIONS: In this study we provide for the first time ex vivo evidence of physiologically relevant protein interactions with NOD2, which are able to trigger the innate immune response in intestinal mucosal specimens of children with CD.
Subject(s)
Crohn Disease/metabolism , Intestinal Mucosa/metabolism , Nod2 Signaling Adaptor Protein/metabolism , Adaptor Proteins, Signal Transducing/genetics , Adaptor Proteins, Signal Transducing/metabolism , Adolescent , Blotting, Western , Case-Control Studies , Child , Child, Preschool , Crohn Disease/pathology , Female , Humans , Immunity, Innate , Immunoblotting , Immunoprecipitation , Intestinal Mucosa/pathology , Male , NF-kappa B/genetics , NF-kappa B/metabolism , Nod2 Signaling Adaptor Protein/genetics , Phosphorylation , RNA, Messenger/genetics , RNA, Messenger/metabolism , Receptor-Interacting Protein Serine-Threonine Kinase 2/genetics , Receptor-Interacting Protein Serine-Threonine Kinase 2/metabolism , Reverse Transcriptase Polymerase Chain Reaction , alpha-Defensins/genetics , alpha-Defensins/metabolismABSTRACT
Celiac disease (CD) is a rare example of multifactorial disorder in which a genetic test is of great clinical relevance, as the disease rarely develops in the absence of specific HLA alleles. We typed DR-DQ genes in 437 Italian children with celiac disease, 834 first-degree relatives, and 551 controls. Of patients, 91% carried DQ2 and/or DQ8 heterodimers, 6% only had beta2 chain, 2% was alpha5 positive, and four were DQ2/DQ8/beta2/alpha5 negative. Only the presence of alpha5 resulted negatively associated to disease (p = 2 x 10(-4)), whereas we confirmed the effect of the beta half of DQ2 dimer on CD predisposition (p = 4 x 10(-12)). Considering 1:100 disease prevalence, we obtained a risk gradient ranging from 1:7 for DQ2 and DQ8 individuals down to 1:2518 for subjects lacking all predisposing factors. The DQB1*02 and DQB1*0302 concurrence (p = 9 x 10(-4)), besides the DQB1*02/*02 homozygosity, had an additional role in disease genetic determination. The CD prevalence rose to 17.6% in sisters, 10.8% in brothers, and 3.4% in parents. In the three groups, the subjects carrying high-risk HLA molecules were 57%, 71%, and 58%; among them, 29%, 15%, and 6% respectively had CD. Those siblings and parents with no susceptible factors were not affected. These findings indicate the impact of the HLA test for CD in clinical practice.
