ABSTRACT
Although food processing can alter food allergenicity, the impact of extrusion processing on in vivo hazelnut allergenicity is unknown. Here, we tested the hypothesis that extrusion processing will alter the immune activation properties of hazelnut protein (HNP) in mice. Soluble extrusion-processed HNP (EHNP) was prepared and evaluated for immune response using an established transdermal sensitization mouse model. Mice were sensitized with identical amounts of EHNP versus raw HNP. After confirming systemic IgE, IgG1 and IgG2a antibody responses, oral hypersensitivity reaction was quantified by hypothermia shock response (HSR). Mechanism was studied by measuring mucosal mast cell (MMC) degranulation. Compared to raw HNP, the EHNP elicited slower but similar IgE antibody (Ab) response, lower IgG1 but higher IgG2a Ab response. The EHNP exhibited significantly lower oral HSR as well as MMC degranulation capacity. These results demonstrate that the extrusion technology can be used to produce soluble HNP with altered immune activation properties.
Subject(s)
Corylus/chemistry , Food Handling , Nut Hypersensitivity/immunology , Nuts/chemistry , Plant Proteins/immunology , Animals , Antibody Formation , Corylus/immunology , Disease Models, Animal , Female , Immunoglobulin E/immunology , Immunoglobulin G/immunology , Mice , Mice, Inbred BALB C , Nut Hypersensitivity/prevention & control , Nuts/immunology , Plant Proteins/isolation & purificationABSTRACT
BACKGROUND: Nut allergy is a growing and potentially fatal public health problem. We have previously reported a novel mouse model of near-fatal hazelnut (HN) allergy that involves transdermal sensitization followed by oral elicitation of allergic reactions. Here we studied the cardiac mast cell and cardiac tissue responses during oral nut induced allergic reaction in this mouse model. METHODS: Groups of mice were sensitized with HN and specific and total IgE were measured by ELISA. Oral allergic reaction was quantified by rectal thermometry and plasma mouse mast cell protease (mMCP)-1 by ELISA. Cardiovascular functions were determined by a non-invasive tail cuff method. Mucosal mast cells (MMC) and intestinal connective tissue MC (CTMC) were studied by immunohistochemistry (IHC) for mMCP-1 and mMCP-4 protein expression respectively. Cardiac MC were studied by toluidine blue (TB) as well as by the above IHC methods. Cytokines and chemokines in the tissues were quantified by a multiplex protein array method. RESULTS: Oral allergen challenge (OAC) of transdermal sensitized mice results in hypothermia, hypotension, tachycardia and rapid elevation of circulating mMCP-1. The IHC analysis of small intestine found significant expansion of mMCP-1+ MMCs and mMCP-4+ CTMCs. The TB analysis of cardiac tissues showed degranulation of majority of cardiac MCs. The IHC analysis of cardiac tissues showed very little mMCP-1 expression, but marked mMCP-4 expression. Furthermore, repeated OAC resulted in significant expansion of mMCP-4+ cardiac MCs in both the pericardium and the myocardium. Protein array analysis revealed significant elevation of cardiac IL-6 and CCR1/3 and CXCR2 signaling chemokines upon oral elicitation compared to sensitization alone. CONCLUSION: These results demonstrate that: (i) besides the intestine, cardiac mast cells and the cardiac tissue respond during oral nut induced allergic reaction; and (ii) repeated oral elicitation of reaction is associated with cardiac mMCP-4+ mast cell expansion and elevation of cardiac IL-6, and CCR1/3 and CXCR2 signaling chemokines.
Subject(s)
Interleukin-6/metabolism , Mast Cells/immunology , Myocardium/metabolism , Nut Hypersensitivity/immunology , Receptors, CCR1/metabolism , Receptors, CCR3/metabolism , Receptors, Interleukin-8B/metabolism , Allergens/immunology , Animals , Chemokine CCL2/blood , Corylus/immunology , Disease Models, Animal , Female , Humans , Immunoglobulin E/blood , Interleukin-6/genetics , Mice , Mice, Inbred BALB C , Myocardium/pathology , Receptors, CCR1/genetics , Receptors, CCR3/genetics , Receptors, Interleukin-8B/genetics , Serine Endopeptidases/metabolism , Signal Transduction , Up-RegulationABSTRACT
OBJECTIVE: To assess an intervention strategy--a 6-week obesity intervention program, Project KidFIT, at 3 Houston, Texas park centers--to address the obesity epidemic in minority children. STUDY DESIGN: Project KidFIT is a physical fitness and nutrition education program aimed at promoting the benefits of physical activity and improving nutrition knowledge in overweight (body mass index [BMI] > or = 95th percentile) minority children. RESULTS: A total of 120 minority children (77 boys and 43 girls; mean age, 10.1 years) were enrolled in the program. Approximately 71% of these children were at risk of overweight (BMI > or = 85th percentile), and 54% were overweight. Decreases in body weight (0.3 +/- 0.2 kg [mean +/- standard error]) and BMI (0.1 +/- 0.1 kg/m2) were detected in the overweight children, whereas increases in body weight (0.4 +/- 0.1 kg) and BMI (0.2 +/- 0.1 kg/m2) were observed in the children with normal body weight (BMI < 85th percentile but > 5th percentile). Significant improvements (P < .05) in flexibility, muscular endurance, and muscular strength were detected in all children, regardless of weight status. CONCLUSIONS: The findings suggest that the city park-based KidFIT program might be effective at promoting stabilization for body weight and BMI and improving physical activity performance and nutrition knowledge in overweight minority children.
