In vitro detection of specific IgE bound to high-affinity receptor on basophils’ surface is 25 a widely used strategy for the evaluation of IgE-mediated immediate hypersensitivity reactions to 26 drugs. Due to the drug small size, IgE recognition requires conjugation to a carrier molecule present 27 in blood. Thus, the conjugate formed is large enough to allow the cross-linking of two IgE bound to 28 the basophil’s surface and their degranulation. However, no information about size and composi-29 tions of these conjugates is available. The use of well-defined hapten-carrier conjugates would be a 30 valuable tool for the investigation of the mechanism through which the activation occurs and could 31 offer clinical potential for diagnosis of drug-allergy. Silica Nanoparticles decorated with PAMAM-32 dendrimer-amoxicilloyl conjugates (NpDeAXO) of different size and amoxicilloyl densities have 33 been prepared and chemically characterized. Their functional effect on basophils was measured 34 using an in-house basophil activation test (BAT) by determining CD63+ or CD203chigh activation 35 markers. It was observed that NpDeAXO nanocomposites are not only able to specifically activate 36 basophils, but also do so with a lower concentration of amoxicilloyl compared to free amoxicillin. 37 These results indicate that NpDeAXO possess high basophil activation potency, pointing to a trans-38 lational potential of this strategy in the context of in vitro allergy determination.
