Jorge R. Mujico

Measurement of wheat gluten and barley hordeins in contaminated oats from Europe, the United States and Canada by Sandwich R5 Elisa

Objectives We have investigated the extent of contamination with wheat, barley, rye or a mixture of these cereals in a large number of grains and commercial oats. We have also attempted to identify the type of cereal contaminant. Methods Sandwich R5 ELISA (using either gliadins or hordeins as standards), western blot, matrix-assisted laser desorption/ionization time-of-flight mass spectrometric and quantitative real-time PCR (Q-PCR) techniques have been used to analyze a total of 134 oats, comprising grains and commercial oat products collected from Europe, the United States and Canada. Results Twenty-five of the 134 pure, uncontaminated oat varieties were found to have undetectable levels of gluten, whereas most of the 109 grains and commercial oat products were mainly contaminated with mixtures of wheat, barley and rye, barley being the predominant contaminant. The percentages of these cereals in the oat samples have been calculated by specific wheat, barley and rye Q-PCR systems. The oat samples were grouped according to the avenin spectra determined by the mass spectrometric technique. The data confirmed that contaminated oat foods, based on the same variety, could have different levels of wheat, barley and rye contamination. Conclusion This study has verified that contamination with wheat gliadins or barley hordeins in oat samples can be measured by the Sandwich R5 ELISA, using either gliadins or hordeins as standards, and also the importance of using confirmatory techniques (such as western blot, Q-PCR and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry) to confirm that most oats are contaminated with mixtures of wheat, barley and rye.

Immune development and intestinal microbiota in celiac disease

Celiac disease (CD) is an immune-mediated enteropathy, triggered by dietary wheat gluten and similar proteins of barley and rye in genetically susceptible individuals. The etiology of this disorder is complex, involving both environmental and genetic factors. The major genetic risk factor for CD is represented by HLA-DQ genes, which account for approximately 40% of the genetic risk; however, only a small percentage of carriers develop the disease. Gluten is the main environmental factor responsible for the signs and symptoms of the disease, but exposure to gluten does not fully explain the manifestation of CD. Epidemiological and clinical data suggest that environmental factors other than gluten might play a role in disease development, including early feeding practices (e.g., breast milk versus formula and duration of breastfeeding), infections, and alterations in the intestinal microbiota composition. Herein, we review what is known about the influence of dietary factors, exposure to infectious agents, and intestinal microbiota composition, particularly in early life, on the risk of developing CD, as well as the possible dietary strategies to induce or increase gluten tolerance.

Influence of early environmental factors on lymphocyte subsets and gut microbiota in infants at risk of celiac disease; the PROFICEL study.

INTRODUCTION It is known that the HLA genotype can explain about a 40% of the genetic risk of celiac disease (CD), thus, other genetic predisposing factors as well as factors that subtly modulate T cell activation and differentiation need to be studied. This includes environmental factors that are currently believed to impact on the immune system and gut microbiota development. AIM To assess the associations between early environmental factors (EEF), lymphocyte subsets, and intestinal microbiota composition in infants at familial risk for CD. STUDY DESIGN Prospective observational study. SUBJECTS Fifty-five 4 month-old infants with at least a first-degree relative suffering CD. Infants were classified according to type of delivery, mothers antibiotic intake during pregnancy and during labor, milk-feeding practices, early infections and antibiotic intake, rotavirus vaccine administration, and allergy incidence within the first 18 months of life. METHODS Lymphocyte subsets and gut microbiota composition were studied at the age of 4 months. RESULTS Formula feeding and infants infections were associated with higher CD3+, CD4+, CD4+CD38+, CD4+CD28+ and CD3+CD4+CD45RO+ counts (P0.01). Infant s infections were also associated with higher CD4+CD25+, CD4+HLA-DR+ and NK cell counts (P0.01). Cesarean delivery and rotavirus vaccine administration were associated with lower percentage of CD4+CD25+ cells. Infants antibiotic intake was associated and correlated with lower counts of Bifidobacterium longum and higher counts of Bacteroides fragilis group. CONCLUSIONS Infant s infections and antibiotic intake in the first 4 months of life are the EEF more strongly and/or frequently associated to lymphocyte subpopulations and microbiota composition, respectively, in infants at risk of CD.

Influence of early environmental factors on lymphocyte subsets and gut microbiota in infants at risk of celiac disease; the PROFICEL study | Influencia de factores ambientales tempranos sobre las subpoblaciones de linfocitos y la microbiota intestinal de niños con riesgo de desarrollar enfermedad celíaca; el estudio PROFICEL

INTRODUCTION It is known that the HLA genotype can explain about a 40% of the genetic risk of celiac disease (CD), thus, other genetic predisposing factors as well as factors that subtly modulate T cell activation and differentiation need to be studied. This includes environmental factors that are currently believed to impact on the immune system and gut microbiota development. AIM To assess the associations between early environmental factors (EEF), lymphocyte subsets, and intestinal microbiota composition in infants at familial risk for CD. STUDY DESIGN Prospective observational study. SUBJECTS Fifty-five 4 month-old infants with at least a first-degree relative suffering CD. Infants were classified according to type of delivery, mothers antibiotic intake during pregnancy and during labor, milk-feeding practices, early infections and antibiotic intake, rotavirus vaccine administration, and allergy incidence within the first 18 months of life. METHODS Lymphocyte subsets and gut microbiota composition were studied at the age of 4 months. RESULTS Formula feeding and infants infections were associated with higher CD3+, CD4+, CD4+CD38+, CD4+CD28+ and CD3+CD4+CD45RO+ counts (P0.01). Infant s infections were also associated with higher CD4+CD25+, CD4+HLA-DR+ and NK cell counts (P0.01). Cesarean delivery and rotavirus vaccine administration were associated with lower percentage of CD4+CD25+ cells. Infants antibiotic intake was associated and correlated with lower counts of Bifidobacterium longum and higher counts of Bacteroides fragilis group. CONCLUSIONS Infant s infections and antibiotic intake in the first 4 months of life are the EEF more strongly and/or frequently associated to lymphocyte subpopulations and microbiota composition, respectively, in infants at risk of CD.

Malnutrition and Inflammation

The relationship between nutrition and immune function is being widely recognized, although its study is relatively recent. The 1968 World Health Organisation monograph about “Interactions between Nutrition and Infection” presented the mechanisms linking infection and poor nutritional status. Following the development of immunology as a science, increasing evidence was obtained as well to show how undernutrition impaired resistance to infections and the immune response. It was initially recognized that deficits in certain micronutrients (like vitamins and minerals) had a direct impact on immune function. But the relationship between immune function and nutrition extends far beyond that, and the term immunonutrition has been coined. We are now aware of many conditions of nutritional imbalance (not all necessarily linked to nutritional deficiencies) that lead to impaired immune response. For instance, it is currently believed that nutrition is a key factor in the onset and development of many types of cancer, or that the dietary component of atherosclerosis risk can directly influence immune cells and the inflammatory response; certain nutrients, like seed and fish oils have been shown to respectively induce the release of proand anti-inflammatory mediators. Accordingly, the idea of undernutrition has been replaced by that of malnutrition, meaning that inappropriate nutrition or nutritional imbalance per se, whether it implies a nutrient deficit or not, influences immune function. That is the reason why overnutrition, or an excessive energy intake, is also now considered as malnutrition. In this chapter we will discuss three paradigmatic cases of malnutrition that have a strong immune and inflammatory impact: anorexia nervosa (AN) and bulimia nervosa (BN), as examples of severe undernutrition; obesity, also referred to as overnutrition; and celiac disease (CD), a pathological reaction of the body to a particular type of nutrients that leads to malnutrition. Although these nutrition-related diseases have different origins (psychological for eating disorders, modifiable lifestyle factors for obesity and autoimmune for CD), they all have in common to present an important inflammatory component and to have nutritional treatment as the main therapeutic approach.

Bacterial immune modulation of the cytokine response elicited by gliadin in an in vitro model ofceliac disease

Presentado en el 6th Internationa Workshop on immunonutrition 15th-17th October 2012 Palma de Mallorca

Influence of early environmental factors on peripheral lymphocyte subsets and gut microbiota in infants at risk for celiac disease

Genetic risk linked to the HLA (Human Leucocyte Antigen) system is not enough to explain the incidence of celiac disease (CD) and other genetic and environmental factors have been suggested to play a role . The immune system and microbiota are not fully developed at birth and single antigen encounter in the intestine is a key process to achieve full development . Environmental factors through this or other route are believed to impact on the immune system and microbiota as well. We sought to assess the effect of several early environmental factors on lymphocyte subsets and microbiota composition in infants at familial risk for CD. For this purpose, 55 infants with a first degree relative suffering CD were recruited before birth. Information on early environmental factors was prospectively collected including type of delivery, mother’s antibiotic intake during pregnancy, mother’s antibiotic administration during labour, milkfeeding practices, infections and antibiotic intake in the first 4 months of life and rotavirus vaccine administration. Lymphocyte subsets in peripheral blood and gut microbiota composition in faeces samples were studied at the age of 4 months by flow cytometry analysis and qPCR respectively. Linear regression analysis showed that, the absolute counts of total lymphocytes, CD3 + , CD4 + , CD4 +CD38+ , CD4+CD28+ , were positively associated with formula-fed infants and infant’s infections in the first 4 months of age. The percentage of CD4 +CD25 + was positively associated with vaginal delivery and antibiotic use by mothers during pregnancy, and negatively with rotavirus vaccine, and their absolute counts were associated positively with infant’s infections. The absolute counts of CD3+CD4+CD45RO + were positively associated with formula-feeding and infant’s infections, and negatively with infant’s antibiotic intake. CD4 +HLA-DR + cell counts were positively associated with infant’s infections. The percentages and absolute counts of NK cells were positively associated with infant’s infections and antibiotic administration in mothers during labor. Regarding microbiota, infant’s antibiotic intake is associated with higher counts of Bacteroides spp. and lower counts of B. longum. Cesarean delivery is associated with higher counts of B. angulatum and lower counts of B. catenulatum. B. angulatum counts were also positively associated with infant’s antibiotic administration in the first 4 months of life and negatively with formula feeding and antibiotic administration during pregnancy. In conclusion, the balance between the effects of the preand post-natal factors on lymphocyte subsets and microbiota composition might modify the risk for future development of immune-related diseases such as celiac disease.