Suchergebnisse

[Background]: Amoxicillin (AX) is nowadays the β-lactam that more frequently induces immediate allergic reactions. Nevertheless, diagnosis of AX allergy is occasionally challenging due to risky in vivo tests and non-optimal sensitivity of in vitro tests. AX requires protein haptenation to form multivalent conjugates with increased size to be immunogenic. Knowing adduct structural features for promoting effector cell activation would help to improve in vitro tests. We aimed to identify the optimal structural requirement in specific cellular degranulation to AX using well-precised nanoarchitectures of different lengths. ; [Method]: We constructed eight Bidendron Antigens (BiAns) based on polyethylene glycol (PEG) linkers of different lengths (600–12,000 Da), end-coupled with polyamidoamine dendrons that were terminally multi-functionalized with amoxicilloyl (AXO). In vitro IgE recognition was studied by competitive radioallergosorbent test (RAST) and antibody–nanoarchitecture complexes by transmission electron microscopy (TEM). Their allergenic activity was evaluated using bone marrow-derived mast cells (MCs) passively sensitized with mouse monoclonal IgE against AX and humanized RBL-2H3 cells sensitized with polyclonal antibodies from sera of AX-allergic patients. ; [Results]: All BiAns were recognized by AX-sIgE. Dose-dependent activation responses were observed in both cellular assays, only with longer structures, containing spacers in the range of PEG 6000–12,000 Da. Consistently, greater proportion of immunocomplexes and number of antibodies per complex for longer BiAns were visualized by TEM. ; [Conclusions]: BiAns are valuable platforms to study the mechanism of effector cell activation. These nanomolecular tools have demonstrated the importance of the adduct size to promote effector cell activation in AX allergy, which will impact for improving in vitro diagnostics. ; The present study was supported by the Institute of Health "Carlos III" (ISCIII) of MINECO (grants cofunded by ERDF: "Una manera de hacer Europa" (grant numbers PI12/02529, PI15/01206, CP15/00103, PI17/01237, PI18/00095, PI20/01734, PI20/01447, RETICS ARADYAL RD16/0006/0001, Euronanomed Program AC19/00082); Andalusian Regional Ministry of Economy and Knowledge (grants cofunded by ERDF: "Andalucía se mueve con Europa": grant no. CTS-06603); Andalusian Regional Ministry of Health (grant nos PI-0699-2011, PI-0179-2014); and "Premio UNICAJA a la innovación en biomedicina y salud." AT has received funding from the European Union's H2020 research and innovation program under the Marie Skłodowska-Curie (grant no. 713721). S.B. acknowledges financial support of Ministerio de Ciencia, Innovación y Universidades from Spain through a Juan de la Cierva Incorporación contract. C.M. holds "Nicolas Monardes" research contract by Andalusian Regional Ministry Health (grant no. RC-0004-2021). G.B. holds a "Juan Rodes" grant (JR18/00054), J.L.P holds a "Sara Borrell" grant (CD19/00250), A.R.N. and M.I.M. hold a "Miguel Servet I" grant (CP19/00191 and CP15/00103), both grants cofunded by European Social Fund ("El FSE invierte en futuro"). Tesfaye reports grants from Marie Skłodowska-Curie [grant No 713721], during the conduct of the study; in addition, Tesfaye has a patent PCT/ES2021/070103 pending. Dr. RODRIGUEZ NOGALES reports grants from ISCIII, during the conduct of the study; in addition, Dr. RODRIGUEZ NOGALES has a patent PCT/ES2021/070103 pending. Dr. Benede reports grants from Ministerio de Ciencia, Innovación y Universidades, during the conduct of the study. Dr. Fernandez reports grants from ISCIII, during the conduct of the study; In addition, Dr. Fernandez has a patent PCT/ES2021/070103 pending. Dr. Paris reports a Sara Borrell fellowship from ISCIII (CD19/00250), cofunded by European Social Fund. Dr. Rodriguez reports grants from ISCIII, during the conduct of the study. JIMÉNEZ-SÁNCHEZ reports grants from MICIN (PEJ2018-002865-A), during the conduct of the study; Dr. BOGAS HERRERA reports grants from ISCIII, during the conduct of the study. Dr. Mayorga reports grants from ISCIII, from Andalusian Regional Ministry Health, during the conduct of the study; in addition, Dr. Mayorga has a patent PCT/ES2021/070103 pending. Dr. Torres reports grants from ISCIII, during the conduct of the study; in addition, Dr. Torres has a patent PCT/ES2021/070103 pending. Dr. Montañez reports grants from ISCIII, during the conduct of the study; in addition, Dr. Montañez has a patent PCT/ES2021/070103 pending. ; Peer reviewed