Synthetic antigenic determinants of clavulanic acid induce dendritic cell maturation and specific T cell proliferation in patients with immediate hypersensitivity reactions

Abstract

Background 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. Methods 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. Results 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%. Conclusions 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.

Shared Clavulanate and Tazobactam Antigenic Determinants Activate T-Cells from Hypersensitive Patients

“…These results can be used to produce better reagents for skin and in vitro diagnostic testing. In fact, a recent study has shown that synthetic antigenic determinants of clavulanic acid can induce improved responses in in vitro diagnostics …”

“…In fact, a recent study has shown that synthetic antigenic determinants of clavulanic acid can induce improved responses in in vitro diagnostics. 36 …”

In vitro diagnostic testing for drug allergy in children

“…In order to improve the reliability and the practicability of the test, different approaches to the classical LTT have been proposed over the years. These modifications 10 regard on one side the attempt to ameliorate the drug‐specific activation by the use of professional antigen presenting cells, 55,56 the inclusion of drug metabolites, 57 the depletion of regulatory T cells, 58 or the evaluation in effector cells 59,60 . On the other hand, newer approaches provide for new read‐out parameters and methods 61 .…”

Biomarkers of immediate drug hypersensitivity

“…33 Moreover, in-house methods, mostly using radiolabeled anti-IgE, are indispensable to overcome sensitivity limitations of the fluoroimmunoassays and analyse the immunological recognition of new chemical structures. In this sense, recent studies have shown the relevance of the inclusion of different determinant antigens for the detection of drug sIgE to cephalosporins, carbapenems and monobactams 34,35 as well as the beta-lactamase inhibitors clavulanic acid (CLV) 36,37 and tazobactam. 38 All these findings suggest the need to include different antigenic structures in the same assay for diagnosing the maximal number of patients, ensuring the detection of different patterns of recognition.…”