A novel tool for clinical diagnosis of allergy operating a microfluidic immunoaffinity basophil activation test technique.

The Basophil Activation Test (BAT) is a valuable allergy diagnostic tool but is time-consuming and requires skilled personnel and cumbersome processing, which has limited its clinical use. We therefore investigated if a microfluidic immunoaffinity BAT (miBAT) technique can be a reliable diagnostic method. Blood was collected from allergic patients and healthy controls. Basophils were challenged with negative control, positive control (anti-FcεRI), and two concentrations of a relevant and non-relevant allergen. CD203c and CD63 expression was detected by fluorescent microscopy and flow cytometry. In basophils from allergic patients the CD63% was significantly higher after allergen activation as compared to the negative control (p<.0001-p=.0004). Activation with non-relevant allergen showed equivalent CD63% expression as the negative control. Further, the miBAT data were comparable to flow cytometry. Our results demonstrate the capacity of the miBAT technology to measure different degrees of basophil allergen activation by quantifying the CD63% expression on captured basophils.