Ariza, AdrianaMayorga, CristobalinaSalas, MaríaDoña, InmaculadaMartín-Serrano, ÁngelaPérez-Inestrosa, EzequielPérez-Sala, DoloresGuzmán, Antonio EMontañez, María ITorres, María J2023-01-252023-01-252016-10-12http://hdl.handle.net/10668/10528The optimal recognition of penicillin determinants, including amoxicillin (AX), by specific IgE antibodies is widely believed to require covalent binding to a carrier molecule. The nature of the carrier and its contribution to the antigenic determinant is not well known. Here we aimed to evaluate the specific-IgE recognition of different AX-derived structures. We studied patients with immediate hypersensitivity reactions to AX, classified as selective or cross-reactors to penicillins. Competitive immunoassays were performed using AX itself, amoxicilloic acid, AX bound to butylamine (AXO-BA) or to human serum albumin (AXO-HSA) in the fluid phase, as inhibitors, and amoxicilloyl-poli-L-lysine (AXO-PLL) in the solid-phase. Two distinct patterns of AX recognition by IgE were found: Group A showed a higher recognition of AX itself and AX-modified components of low molecular weights, whilst Group B showed similar recognition of both unconjugated and conjugated AX. Amoxicilloic acid was poorly recognized in both groups, which reinforces the need for AX conjugation to a carrier for optimal recognition. Remarkably, IgE recognition in Group A (selective responders to AX) is influenced by the mode of binding and/or the nature of the carrier; whereas IgE in Group B (cross-responders to penicillins) recognizes AX independently of the nature of the carrier.enAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/AdultAgedAmoxicillinAnaphylaxisAntibody SpecificityButylaminesCarrier ProteinsCross ReactionsDrug HypersensitivityFemaleHaptensHumansHypersensitivity, ImmediateImmunoglobulin EMaleMiddle AgedPenicillinsPolylysineSerum Albumin, HumanUrticariaYoung Adultbeta-Lactamsresearch article27731424open access10.1038/srep351132045-2322PMC5059705https://www.nature.com/articles/srep35113.pdfhttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC5059705/pdf