Tick Salivary Extract Induces Alpha-Gal Allergy in Alpha-Gal Deficient Mice

Abstract

RATIONALE: Recent retrospective research associated early life acid suppressive medication with food allergies. We sought to prospectively evaluate the association between acid suppressive medication in infancy and development of IgE-mediated food allergy in early childhood. METHODS: The Gastrointestinal Microbiome and Allergic Proctocolitis (GMAP) Study is an ongoing prospective observational cohort study of 1003 healthy newborn infants designed to evaluate the development of food allergies in their first 3 years of life. IgE-mediated food allergy was determined by independent agreement of two allergist reviewers based on clinical reactivity and documented IgE sensitivity. RESULTS: 797 infants were analyzed (46% female, 89% term, 31% delivered via caesarian-section, 8% neonatal antibiotics) with a current median age of 36 [19, 54] months. 153 (19%) were exposed to acid suppressive medication, 45 (5%) were exposed to a proton pump inhibitor and 115 (13%) were exposed to a histamine-2 receptor antagonist, in their first six months of life. To date, 51 (6%) of children have developed a confirmed or probable IgE-mediated food allergy, most commonly to egg, peanut, tree nuts, and milk. Use of acid suppressive medication in the first six months of life was not associated with development of IgE-mediated food allergy in early childhood (OR 0.77 [0.31, 1.71], p50.59). CONCLUSIONS: Contrary to a recent retrospective report, early exposure to acid suppressive medication is not prospectively associated with development of IgE-mediated food allergy by age 3 in this cohort. J ALLERGY CLIN IMMUNOL FEBRUARY 2019 AB252 Abstracts MONDAY

On the cause and consequences of IgE to galactose-α-1,3-galactose: A report from the National Institute of Allergy and Infectious Diseases Workshop on Understanding IgE-Mediated Mammalian Meat Allergy

“…These mice produced an a-Gal-directed IgE response and also demonstrated systemic allergic reactions, as measured by a decrease in body temperature, following injection of a-Gal-containing antigen (cetuximab) or gavage with pork. 101,102 As stated above, a recent article by Chandrasekhar et al 98 provides additional evidence that the skin plays an important role in sensitization to tick proteins. Subcutaneous inoculation of A americanum larval extracts (whole body), but not intraperitoneal injection of the same extracts, elicited a robust tick-specific IgE response in wild-type mice.…”