New Approaches for Basophil Activation Tests Employing Dendrimeric Antigen-Silica Nanoparticle Composites.

In vitro cell activation through specific IgE bound to high-affinity receptors on the basophil surface is a widely used strategy for the evaluation of IgE-mediated immediate hypersensitivity reactions to betalactams. Cellular activation requires drug conjugation to a protein to form a large enough structure displaying a certain distance between haptens to allow the cross-linking of two IgE antibodies bound to the basophil's surface, triggering their degranulation. However, no information about the size and composition of these conjugates is available.

Multiepitope Dendrimeric Antigen-Silica Particle Composites as Nano-Based Platforms for Specific Recognition of IgEs.

β-lactam antibiotics (BLs) are the drugs most frequently involved in drug hypersensitivity reactions. However, current diagnostic tests have limited sensitivity, partly due to a poor understanding of drug-protein conjugates that both induce the reactions and are immunologically recognized. Dendrimeric Antigen-Silica particle composites (DeAn@SiO), consisting on nanoparticles decorated with BL-DeAns are promising candidates for improving the clinical diagnostic practice.

The value of the basophil activation test in the evaluation of patients reporting allergic reactions to the BNT162b2 mRNA COVID-19 vaccine.

Background: mRNA-based COVID-19 vaccines have been reported to induce hypersensitivity reactions (HSR) in a small number of individuals. We aimed to evaluate the real-world incidence of the BNT162b2 mRNA COVID-19 vaccine HSR and to determine the value of the basophil activation test (BAT) in the allergological workup of patients reporting these reactions.

Methods: We prospectively enrolled patients with a clinical history indicative of HSR to the BNT162b2 mRNA COVID-19 vaccine.