Characterization of Mouse Anti-Crude Peanut Extract IgE Monoclonal Antibodies

Abstract INTRODUCTION: Immediate hypersensitivity reactions to peanuts, an IgE-mediated food allergy, are a major public health concern. For allergic patients, avoidance currently remains the only viable option. Mouse peanut allergy models are used for studying pathogenesis and therapeutics, However, establishing animal models with high IgE antibody titers is difficult. OBJECTIVE: Newly developed mouse anti-crude peanut extract (CPE) IgE monoclonal antibodies (mAbs) were evaluated with in-vitro and in-vivo assays used for studying the pathogenesis of and therapeutics against peanut allergies. METHODS and RESULTS: Four hybridomas that produce IgE mAbs against CPE were established from BALB/c mice orally administrated CPE with cholera toxin. All mAbs recognized the Ara h1 allergen in CPE by western blot and worked dose dependently in sandwich ELISAs using an anti-IgE capture mAb and biotinylated CPE. However, only three mAbs worked in indirect ELISAs with CPE coated plates, depending on individual epitope specificities. The three mAbs degranulated RBL-2H3 cells and their degrees of activation varied by mAbs and concentration. In female BALB/c mice, two mAbs developed footpad delayed type hypersensitivity, which peaked at 1–2 hours after sensitization and drop in body temperature in anaphylaxis reactions, which peaked at 40–60 minutes after an IV injection of CPE. CONCLUSION: Two out of four IgE mAbs can work for both in-vitro and in-vivo peanut allergy studies. Particularly, the mAbs can develop allergic reactions with sensitization alone in mice. This will be especially useful to evaluate therapeutic methods associated with mast cell activation as the mAbs can accelerate studies with no lengthy immunization protocols.