Site-selective chemoenzymatic glycoengineering of Fab and Fc glycans of a therapeutic antibody
- Proc Natl Acad Sci U S A. 2018 Nov 20;115(47):12023-12027. doi: 10.1073/pnas.1812833115.
- 1. Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742.
- 2. Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201.
- 3. Laboratory of Molecular Genetics and Immunology, The Rockefeller University, New York, NY 10065.
- 4. Laboratory of Molecular Genetics and Immunology, The Rockefeller University, New York, NY 10065 [email protected] [email protected].
- 5. Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742; [email protected] [email protected].
The N-glycans attached to the Fab and Fc domains play distinct roles in modulating the functions of antibodies. However, posttranslational site-selective modifications of glycans in antibodies and other multiply glycosylated proteins remain a challenging task. Here, we report a chemoenzymatic method that permits independent manipulation of the Fab and Fc N-glycans, using cetuximab as a model therapeutic monoclonal antibody. Taking advantage of the substrate specificity of three endoglycosidases (Endo-S, Endo-S2, and Endo-F3) and their glycosynthase mutants, together with an unexpected substrate site-selectivity of a Bacterial α1,6-fucosidase from Lactobacillus casei (AlfC), we were able to synthesize an optimal homogeneous glycoform of cetuximab in which the heterogeneous and immunogenic Fab N-glycans were replaced with a single sialylated N-glycan, and the core-fucosylated Fc N-glycans were remodeled with a nonfucosylated and fully galactosylated N-glycan. The glycoengineered cetuximab demonstrated increased affinity for the FcγIIIa receptor and significantly enhanced antibody-dependent cell-mediated cytotoxicity (ADCC) activity.
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Cat. No.Product NameDescriptionTargetResearch Area
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target: GlycosidaseResearch Areas: Others