Glycoengineered CD20 antibodies bind to CD16B with higher affinity than their non–glycoengineered wild-type counterparts. (A) The dissociation constants of the glycoengineered (GE; striped bars) and nonglycoengineered wild-type formats (WT, black bars) of obinutuzumab (OBZ) and rituximab (RTX) for purified soluble CD16B-NA2, CD32A-R131, or CD32A-H131 proteins were measured by surface plasmon resonance. (B) The glycoengineered (GE) and nonglycoengineered wild-type (WT) CD20 antibodies were cross-linked with FITC-labeled anti-κ light chain F(ab’)2, and binding to purified PMNs from NA1 (grey bars) and NA2 homozygous donors (black bars) was measured by flow cytometry. The results are the mean fluorescence intensity ratios of glycoengineered vs wild-type rituximab (RTX) or obinutuzumab (OBZ), obtained from 4 experiments using at least 3 different donors for each CD16B isoform.
