RT Journal Article T1 Synthetic antigenic determinants of clavulanic acid induce dendritic cell maturation and specific T cell proliferation in patients with immediate hypersensitivity reactions. A1 Fernandez-Santamaria, Ruben A1 Bogas, Gador A1 Montañez, Maria Isabel A1 Ariza, Adriana A1 Salas, Maria A1 Cespedes, Jose Antonio A1 Labella, Marina A1 Paris, Juan Luis A1 Perez-Sanchez, Natalia A1 Perez-Inestrosa, Ezequiel A1 Vida, Yolanda A1 Fernandez, Tahia D A1 Mayorga, Cristobalina A1 Torres, Maria Jose K1 Antigenic determinants K1 Clavulanic acid K1 Immediate drug hypersensitivity reactions K1 Maturation K1 Proliferation AB Immediate drug hypersensitivity reactions (IDHRs) to clavulanic acid (CLV) have increased in the last decades due to a higher consumption alongside amoxicillin (AX). Due to its chemical instability, diagnostic procedures to evaluate IDHRs to CLV are difficult, and current in vitro assays do not have an optimal sensitivity. The inclusion of the specific metabolites after CLV degradation, which are efficiently recognised by the immune system, could help to improve sensitivity of in vitro tests. Recognition by dendritic cells (DCs) of CLV and the synthetic analogues of two of its hypothesised antigenic determinants (ADs) was evaluated by flow cytometry in 27 allergic patients (AP) and healthy controls (HC). Their ability to trigger the proliferation of T cells was also analysed by flow cytometry. The inclusion of synthetic analogues of CLV ADs, significantly increased the expression of maturation markers on DCs from AP compared to HC. A different recognition pattern could be observed with each AD, and, therefore, the inclusion of both ADs achieves an improved sensitivity. The addition of synthetic ADs analogues increased the proliferative response of CD4+ Th2 compared to the addition of native CLV. The combination of results from both ADs increased the sensitivity of proliferative assays from 19% to 65% with a specificity higher than 90%. Synthetic ADs from CLV are efficiently recognised by DCs with ability to activate CD4+ Th2 cells from AP. The combination of analogues from both ADs, significantly increased the sensitivity of DC maturation and T-cell proliferation compared to native CLV. PB John Wiley and Sons YR 2022 FD 2022-09-28 LK http://hdl.handle.net/10668/19901 UL http://hdl.handle.net/10668/19901 LA en NO Fernandez-Santamaria R, Bogas G, Montañez MI, Ariza A, Salas M, Cespedes JA, et al. Synthetic antigenic determinants of clavulanic acid induce dendritic cell maturation and specific T cell proliferation in patients with immediate hypersensitivity reactions. Allergy. 2022 Oct;77(10):3070-3083. NO This work has been supported by Institute of Health ‘Carlos III’ (ISCIII) of the Ministry of Economy and Competitiveness (MINECO) (grants co- funded by European Regional Development Fund: PI15/01206, PI17/01237, PI18/00095, PI20/01734, RETICS ARADYAL RD16/0006/0001); Andalusian Regional Ministry of Health (grants PI- 0241- 2016, PE- 0172- 2018, PI- 0127- 2020); Spanish Ministerio de Ciencia e Innovación (Proyectos de I+D+I «Programación Conjunta Internacional», EuroNanoMed 2019 (PCI2019- 111825- 2), Ministerio de Ciencia y Educación (PID2019- 104293GB- I00), I nstituto de Salud Carlos III (ISCIII) of MINECO (RD16/0006/0012), Junta de Andalucía ( PY20_00384 ). AA and NPS hold Senior Postdoctoral Contracts (RH- 0099- 2020 and RH- 0085- 2020) from Andalusian Regional Ministry of Health (cofunded by European Social Fund (ESF): ‘Andalucía se mueve con Europa’). JLP holds a Sara Borrell fellowship (CD19/00250) by ISCIII of MINECO (cofunded by ESF, “El FSE invierte en futuro”). GB holds a ‘Juan Rodes’ contract (JR18/00054) by ISCIII of MINECO (cofunded by ESF). MIM holds a ‘Miguel Servet II’ grant (CPII20/00028) by ISCIII of MINECO (cofunded by ESF). ML holds a ‘Rio Hortega’ contract (CM20/00210) by ISCIII of MINECO (cofunded by ESF). CM holds a ‘Nicolas Monardes’ research contract by Andalusian Regional Ministry Health (RC- 0004- 2021). NMR experiments for characterizing molecule structures have been performed in the ICTS ‘NANBIOSIS’, by the U28 Unit at the Andalusian Centre for Nanomedicine and Biotechnology (BIONAND). DS RISalud RD Aug 8, 2025