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Neuromuscular blocking agents (NMBAs) relax skeletal muscles to facilitate surgeries and ease intubation but can lead to adverse reactions, including complications because of postoperative residual neuromuscular blockade (rNMB) and, in rare cases, anaphylaxis. Both adverse reactions vary between types of NMBAs, with rocuronium, a widely used nondepolarizing NMBA, inducing one of the longest rNMB durations and highest anaphylaxis incidences. rNMB induced by rocuronium can be reversed by the synthetic γ-cyclodextrin sugammadex. However, in rare cases, sugammadex can provoke anaphylaxis. Thus, additional therapeutic options are needed. Rocuronium-induced anaphylaxis is proposed to rely on preexisting rocuronium-binding antibodies. To understand the pathogenesis of rocuronium-induced anaphylaxis and to identify potential therapeutics, we investigated the memory B cell antibody repertoire of patients with suspected hypersensitivity to rocuronium. We identified polyclonal antibody repertoires with a high diversity among V(D)J genes without evidence of clonal groups. When recombinantly expressed, these antibodies demonstrated specificity and low affinity for rocuronium without cross-reactivity for other NMBAs. Moreover, when these antibodies were expressed as human immunoglobulin E (IgE), they triggered human mast cell activation and passive systemic anaphylaxis in transgenic mice, although their affinities were insufficient to serve as reversal agents. Rocuronium-specific, high-affinity antibodies were thus isolated from rocuronium-immunized mice. The highest-affinity antibody was able to reverse rocuronium-induced neuromuscular blockade in nonhuman primates with kinetics comparable to that of sugammadex. Together, these data support the hypothesis that antibodies cause anaphylactic reactions to rocuronium and pave the way for improved diagnostics and neuromuscular blockade reversal agents.

Background: In addition to the clinical burden, asthma is responsible for a high economic burden. However, little is known about the economic burden of asthma prior to death., Objective: We performed an economic analysis to describe the costs during 12 and 24 months prior to asthma death between 2013 and 2017 in France., Methods: An observational cohort study was established using the French national health insurance database. Direct medical and non-medical costs, as well as costs related to absence from the workplace, were included in the analysis., Results: In total, 3,829 patients were included in the final analysis. Over 24 and 12 months prior to death, total medical costs per patient were €27,542 [26,545-28,641] and €16,815 [16,164-17,545], respectively. Total medical costs clearly increased over 24 months prior to death. Over 12 months prior to death, costs increased significantly according to age categories, with mean total costs of €8,592, €15,038, and €17,845, respectively, for the categories <18 years old, 18-75 years old, and 75+ years old ( p  < 0.0001). Over 12 months prior to death, costs were statistically higher in patients with a dispensation of six or more SABA canisters compared to those with a dispensation of five or less canisters ( p  < 0.0001). In multivariate analysis, comorbidities, hospital as location of death, and dispensation of 12 or more canisters of SABA per year are independent factors of the highest costs., Conclusion: To conclude, the economic burden of asthma death is high and increases with time, age, and SABA dispensation., Competing Interests: LG has been an investigator in clinical trials for AstraZeneca, MSD and Novartis, reports grants or consultation fees from AstraZeneca, GlaxoSmithKline, Novartis and Sanofi-Regeneron, and consultation fees from Bayer, Chiesi, MSD, not related to the work submitted. AD reports consultation fees from AstraZeneca, GlaxoSmithKline, Novartis, Sanofi-Regeneron, Chiesi, ALK and Stallergenes, not related to the work submitted. LR reports consultations fees from Argenx, Neovacs and Novartis, not related to the work submitted. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Guilleminault, Mounié, Sommet, Camus, Didier, Reber, Conte and Costa.)

Background: Despite their central role in peanut allergy, human monoclonal IgE antibodies have eluded characterization., Objective: We sought to define the sequences, affinities, clonality, and functional properties of human monoclonal IgE antibodies in peanut allergy., Methods: We applied our single-cell RNA sequencing-based SEQ SIFTER discovery platform to samples from allergic individuals who varied by age, sex, ethnicity, and geographic location in order to understand commonalities in the human IgE response to peanut allergens. Select antibodies were then recombinantly expressed and characterized for their allergen and epitope specificity, affinity, and functional properties., Results: We found striking convergent evolution of IgE monoclonal antibodies (mAbs) from several clonal families comprising both memory B cells and plasmablasts. These antibodies bound with subnanomolar affinity to the immunodominant peanut allergen Ara h 2, specifically a linear, repetitive motif. Further characterization of these mAbs revealed their ability to single-handedly cause affinity-dependent degranulation of human mast cells and systemic anaphylaxis on peanut allergen challenge in humanized mice. Finally, we demonstrated that these mAbs, reengineered as IgGs, inhibit significant, but variable, amounts of Ara h 2- and peanut-mediated degranulation of mast cells sensitized with allergic plasma., Conclusions: Convergent evolution of IgE mAbs in peanut allergy is a common phenomenon that can reveal immunodominant epitopes on major allergenic proteins. Understanding the functional properties of these molecules is key to developing therapeutics, such as competitive IgG inhibitors, that are able to stoichiometrically outcompete endogenous IgE for allergen and thereby prevent allergic cascade in cases of accidental allergen exposure., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)