All abstracts are strictly embargoed until the date of presentation at the 2012 Annual Meeting J ALLERGY CLIN IMMUNOL Abstracts AB1 VOLUME 129, NUMBER 2 A Mutation in the Human Uncoordinated 119 Gene Impairs TCR Rapid Induction of Tolerance To Peanut By Antigen-coupled Cell 1 Signaling and is Associated with CD4 Lymphopenia. 3 Transfer M. M. Gorska1,2, R. Alam1,2; 1National Jewish Health, Denver, CO, C. Hsu, C. B. Smarr, A. J. Byrne, S. D. Miller, P. J. Bryce; Northwestern 2University of Colorado Denver, Aurora, CO. University, Chicago, IL. RATIONALE: Idiopathic CD4 Lymphopenia (ICL) is an immunodefi- RATIONALE: Food allergy is an increasing worldwide health concern. ciency syndrome of unclear etiology. Lck is a major TCR-linked kinase. Immunotherapy is an effective therapeutic approach but has a high risk of Lck activity was reported to be reduced in ICL. We hypothesized that ICL adverse reaction. New methods to efficiently and safely induce antigen- was associated with a defect of the recently described Lck activator specific tolerance could improve the clinical approach to food allergy. 1- -Uncoordinated 119 (Unc119). ethyl-3-(3’-dimethylaminopropyl)-carbodiimide (ECDI) is a non-toxic METHODS: CD4 T cells from three ICL patients were analyzed for Lck chemical used to link antigens to cells (Ag-SP) and has been used in activity (immune-complex kinase assay), the Unc119 protein level (west- clinical trials and shown to promote tolerance in Th1/Th17 autoimmune ern blotting) and sequence of the Unc119 cDNA and exons. The identified diseases. However, the tolerizing effect of Ag-SP on Th2-associated mutant cDNA was expressed in normal CD4 T cells by retroviral infection diseases is still unclear. and the cells were examined for Lck activation and proliferation. METHODS: For the peanut (WPE)-induced murine food allergy model, SATURDAY RESULTS: All ICL patients demonstrated reduced Lck activity. The level mice were orally sensitized with WPE/SEB or SEB and were tolerized with of the Unc119 protein and its molecular weight were normal. One patient Ag-SP before or after sensitization. Anti-CD25 antibody (PC61) was given had heterozygous missense mutation (codon 22 GGC/GTC; V22G) in right after tolerance induction. Disease severity was determined after the Unc119 cDNA and gene. The patient was a 32-year-old female with challenge. Murine bone marrow derived mast cells (BMMCs) were <300 CD4 T cells/ml, recurrent sinusitis/otitis media, recurrent shingles, generated in vitro by culturing with IL-3. BMMCs were cultured with fungal skin and nail infection, oral herpetic lesions and BOOP following Ag-SP or free WPE alone and degranulation was analyzed by b-hexosa- two episodes of bacterial pneumonia. The reduced Lck activity was minidase assay. accompanied by decreased T cell proliferation. Transduction of the mutant RESULTS: In vivo, we show that Ag-SP tolerance prevented WPE- but not wild type Unc119 into normal T cells reproduced signaling and specific responses including WPE-specific IgE and mMCP-1 production proliferation defects. The mutation disrupted the Unc119-Lck interaction, and core body temperature decrease upon oral challenge. Ag-SP tolerance which is essential for Lck activation. The mutant also caused mislocaliza- also reduced disease severity prophylactically without inducing anaphy- tion of Lck to endosomes. The mutation was not present in two other ICL laxis during tolerization compared to mice received free antigens. Ag-SP patients, patients with secondary CD4 lymphopenia or 60 healthy subjects. induced tolerance was partially dependent on CD25+ Tregs since PC61 CONCLUSIONS: We identified a novel genetic defect -a dominant treatment restored allergic responses. Furthermore, Ag-SP did not induce negative missense mutation in the Unc119 gene in ICL. mast cell degranulation in vitro. CONCLUSIONS: Ag-SP tolerance can be rapidly, safely and efficiently Delayed Food Challenge Reactions Correspond Temporally to the induced and highlights a potential new Ag-specific tolerance immuno- 2 Appearance of CD63+ Basophils in Subjects with IgE to alpha-Gal therapy for food allergic diseases. S. Mozzicato1, H. R. James1, M. H. Land2, S. L. Pochan1, L. J. Workman1, T. A. E. Platts-Mills1, S. P. Commins1; 1University of Virginia, Charlottes- Increased FcεRI Expression on Basophils at Birth Predicts ville, VA, 2Duke University, Durham, NC. 4 Subsequent Allergic Sensitization RATIONALE: Allergen-stimulated basophil activation can be assessed D. J. Jackson, M. D. Evans, S. Sahu, R. E. Gangnon, J. E. Gern, R. F. Le- using the activation markers CD63 and CD203c. Patients who develop IgE manske, Jr; University of Wisconsin School of Medicine and Public to the oligosaccharide galactose-alpha-1,3-galactose (alpha-gal) report Health, Madison, WI. reactions that occur 3-6 hours after eating mammalian meat. The purpose RATIONALE: Animal models have demonstrated that basophils can act of this study was to document the clinical delay and assess in vivo activa- as antigen presenting cells and serve as important initiators and amplifiers tion of basophils. of a Th2 response, in part through high-affinity IgE receptor (FcεRI)- METHODS: Following local IRB approval, informed consent was mediated antigen uptake. We sought to determine whether FcεRI expres- obtained from subjects (n56) who reported delayed urticarial reactions sion on mononuclear cells and basophils in early life is associated with the and tested positive for IgE to alpha-gal. After baseline blood work was subsequent development of allergic disease. obtained, 86grams of beef was consumed. Peripheral blood was drawn METHODS: Children at high-risk for asthma and allergy based upon hourly to assess for in vivo activation by flow cytometry using CD63 and parental histories were enrolled at birth and followed prospectively in the CD203c expression. Childhood Origins of ASThma (COAST) study. FcεRI expression on RESULTS: In each challenge, symptoms did not appear until >_3.5 hours basophils, plasmacytoid dendritic cells (pDCs), myeloid dendritic cells after eating meat (range 3.5-5.5 hrs). Symptoms included pruritus, GI (mDCs), and monocytes was determined by flow cytometry of cord blood upset, urticaria, flushing and anaphylaxis. Basophil activation, as increased from 49 children. In vitro IgE was assessed at 1, 3, and 6 years by CD63 expression, was seen 4-5 hours post-meat consumption. The average ImmunocapÒ; values >_ 0.35 KU/L were considered positive. maximum CD63 expression was 20.3 % above unstimulated basophils RESULTS: Cord blood basophil FcεRIa median fluorescence intensity (range 2.2%-60.2%), whereas the expression of CD203c was not increased (MFI) was higher in children who developed aeroallergen sensitization by during the food challenge. Patterns of activation were not affected by sIgE age 1 year compared to those without aeroallergen sensitization (median, titer to alpha-gal nor by ratio of sIgE:total IgE. 2300 vs. 996; p50.005). Similar relationships were seen for the develop- CONCLUSIONS: In the recently described red meat allergy, we report ment of aeroallergen sensitization at ages 3 years (2306 vs. 876; p50.0008) not only documentation of the clinical delay but also the first experiments and 6 years (2191 vs. 996; p50.04). showing that basophils are activated in vivo during a food challenge. CONCLUSIONS: Increased expression of FcεRIa on the surface of Moreover, these results support the utility of CD63 as a marker for food al- basophils in cord blood predicts the subsequent development of allergic lergy-induced basophil activation and imply that the form of alpha-gal sensitization to aeroallergens. Whether this is a predictive biomarker or which causes basophil activation and urticaria takes 4 hours to enter the actually causal in the development of allergic sensitization warrants further bloodstream. study. ABS 5.1.0 DTD YMAI9324_proof 12 January 2012 7:27 pm All abstracts are strictly embargoed until the date of presentation at the 2012 Annual Meeting AB2 Abstracts J ALLERGY CLIN IMMUNOL SATURDAY FEBRUARY 2012 Bronchial Hyperresponsiveness in sportschildren; Different Mannitol Bronchoprovocation in the Evaluation of Airway 5 methods to reach a diagnosis 7 Reactivity in a High-Risk Pediatric Cohort L. Arochena, M. Fernandez-Nieto, V. Andregnette, M. Garcia del Potro, A. Y. Okupa, D. J. Jackson, C. A. Sorkness, V. P. Rajamanickam, T. J. E. Aguado, J. Sastre; Fundacion Jimenez Diaz, Madrid, SPAIN. Kang, I. A. Awoyinka, E. L. Anderson, R. F. Lemanske, Jr; University RATIONALE: There are several methods for the diagnosis of bronchial of Wisconsin, Madison, WI. hyperresponsiveness (BHR). Eucapnic voluntary hyperventilation test RATIONALE: The aim of this study was to examine the properties of a (EVHT) is proposed as the gold standard to diagnose exercise-induced new indirect bronchoprovocation test using inhaled mannitol (AridolTM) asthma (EIA). for evaluating airway hyperreactivity and its relationship with various We have compared the utility of three techniques in asthmatic phenotypic characteristics in children. sportschildren. METHODS: Children at high risk for development of asthma and allergic METHODS: We studied 17 patients (11 boys, 6 girls) aged between 10 disease based on parental histories were enrolled at birth into the and 17 (average 13.65 + 2,49 years), 12 of them belonging to official sports Childhood Origins of Asthma (COAST) study and followed prospectively. teams. At age 11 years, 171 children underwent a mannitol challenge. A positive On the first visit skin prick