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

Abstract

β-Lactamase inhibitors such as clavulanic acid and tazobactam were developed to overcome β-lactam antibiotic resistance. Hypersensitivity reactions to these drugs have not been studied in detail, and the antigenic determinants that activate T-cells have not been defined. The objectives of this study were to (i) characterize clavulanate-and tazobactam-responsive Tcells from hypersensitive patients, (ii) explore clavulanate and tazobactam Tcell crossreactivity, and (iii) define the antigenic determinants that contribute to T-cell reactivity. Antigen specificity, pathways of T-cell activation, and crossreactivity with clavulanate-and tazobactam-specific T-cell clones were assessed by proliferation and cytokine release assays. Antigenic determinants were analyzed by mass spectrometry-based proteomics methods. Clavulanateand tazobactam-responsive CD4 + T-cell clones were stimulated to proliferate and secrete IFN-γ in an MHC class II-restricted and dose-dependent manner. T-cell activation with clavulanate-and tazobactam was dependent on antigen presenting cells because their fixation prevented the T-cell response. Strong crossreactivity was observed between clavulanate-and tazobactam-T-cells; however, neither drug activated β-lactam antibiotic-responsive T-cells. Mass spectrometric analysis revealed that both compounds form multiple antigenic determinants with lysine residues on proteins, including an overlapping aldehyde and hydrated aldehyde adduct with mass additions of 70 and 88 Da, respectively. Collectively, these data show that although clavulanate and tazobactam are structurally distinct, the antigenic determinants formed by both drugs overlap, which explains the observed Tcell cross-reactivity.

Biomarkers of immediate drug hypersensitivity

“…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. On the other hand, great efforts are being made in the implementation of more sensitive detection methods by using ultra-sensitive chemiluminescence immunoassay, 39 and a multiplex microimmunoassay, 40 with traditional cellulose discs (83% for AX, 78% for BP), and interestingly, the detection of false-positive results of BP sIgE for confirmed AX-selective patients decreased from 41% for cellulose discs to 0% for nanoparticles.…”

“…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.…”