Allergen-specific human IgE isolated through an allergen-agnostic pipeline-understanding immune response and allergen recognition.

Allergy, characterised by antibody responses of the IgE isotype, is a major health concern. The set of monoclonal human IgE used for studying the molecular mechanisms of allergies is limited. Single-cell sequencing offers opportunities to establish novel antibodies for researching, diagnosis, and treatment of allergies. We describe and exploit a pipeline for generating recombinant IgE directly from the immune repertoires of allergic subjects. It uses single-cell sequencing of IgM- B cells of bone marrow and peripheral blood in an allergen-agnostic manner, combined with high-throughput transcriptome sequencing to identify clonotypes populating the IgE repertoire. Immunochemical and immunoprecipitation analyses are used to deconvolute the specificity of identified antibodies. High-affinity antibodies were raised against four grass pollen allergens, antibodies that illustrated aspects of the development of allergen-specific humoral immunity. The pipeline provides a streamlined approach for the development and characterisation of native allergen-specific antibodies as they occur in allergy and during allergy desensitisation.