Omalizumab is a widely used therapeutic anti-IgE antibody. Here we report the crystal structure of the omalizumab-Fab in complex with an IgE-Fc fragment. This structure reveals the mechanism of omalizumab-mediated inhibition of IgE interactions with ...
Omalizumab is a widely used therapeutic anti-IgE antibody. Here we report the crystal structure of the omalizumab-Fab in complex with an IgE-Fc fragment. This structure reveals the mechanism of omalizumab-mediated inhibition of IgE interactions with both high- and low-affinity IgE receptors, and explains why omalizumab selectively binds free IgE. The structure of the complex also provides mechanistic insight into a class of disruptive IgE inhibitors that accelerate the dissociation of the high-affinity IgE receptor from IgE. We use this structural data to generate a mutant IgE-Fc fragment that is resistant to omalizumab binding. Treatment with this omalizumab-resistant IgE-Fc fragment, in combination with omalizumab, promotes the exchange of cell-bound full-length IgE with omalizumab-resistant IgE-Fc fragments on human basophils. This combination treatment also blocks basophil activation more efficiently than either agent alone, providing a novel approach to probe regulatory mechanisms underlying IgE hypersensitivity with implications for therapeutic interventions.
Organizational Affiliation:
Sean N. Parker Center for Allergy Research at Stanford University, Stanford University School of Medicine, Stanford, California 94305, USA.,Department of Structural Biology, Stanford University School of Medicine, Stanford, California 94305, USA.,Department of Rheumatology, Immunology and Allergology, University Hospital Bern, Bern 3012, Switzerland.,Progam in Immunology, Stanford University School of Medicine, Stanford, California 94305, USA.,Department of Clinical Research, University of Bern, Bern 3012, Switzerland.,Department of Medicine, Stanford University School of Medicine, Stanford, California 94305, USA.
Download Mendeley
Download Endnote
