2.6 BLI-based binding IgG immune-complexes
A comparison of binding kinetics between IgG or IgG in complex with dimeric Fel d 1 and FcγRIIb (CD32b) was also performed using BLI assays. Briefly, SAX biosensors were saturated with 2 µg/ml of human recombinant biotinylated FcγRIIb (CD32b) followed by association with 25 nM of either monomeric IgG1 and IgG4 F127 or in pre-complexed form with 25 nM Fel d 1 for 300 s. Dissociation was also performed in 300 s in kinetics buffer. Drift control was performed with a loaded sensor dipped in kinetics buffer only. The resulting data were normalized to the highest response, using OriginPro (OriginLab Corporation, Northampton, MA, USA) software analysis