IgG-Fc-mediated effector functions: molecular definition of interaction sites for effector ligands and the role of glycosylation
Article first published online: 28 APR 2006
Volume 163, Issue 1, pages 59–76, June 1998
How to Cite
Jefferis, R., Lund, J. and Pound, J. D. (1998), IgG-Fc-mediated effector functions: molecular definition of interaction sites for effector ligands and the role of glycosylation. Immunological Reviews, 163: 59–76. doi: 10.1111/j.1600-065X.1998.tb01188.x
- Issue published online: 28 APR 2006
- Article first published online: 28 APR 2006
Summary: The Fr region of human IgG expresses interaction sites for many effector ligands. In this review the topographical distributions often of these sites are discussed in relation to functional requirement. It is apparent that interaction sites localised to the inter-CH2-CH3 domain region of the Fc allow for functional divalency, whereas sites localised to the hinge proximal region of the CH2 domain are functionally monovalent, with expression of the latter sites being particularly dependent on glycosylation. All x-ray crystal structures for Fc and Fc-ligand complexes report that the protein structure of the hinge proximal region of the CH2 domain is “disordered”, suggesting “internal mobility”. We propose a model in which such “internal mobility” results in the generation of a dynamic equilibrium between multiple conformers, certain of which express interaction sites specific to individual ligands. The emerging understanding of the influence of oligosaccharide/protein interactions on protein conformation and biological function of IgG antibodies suggests a potential to generate novel glycoforms of antibody molecules having unique profiles of effector functions.