One-step synthesis of site-specific antibody–drug conjugates by reprograming IgG glycoengineering with LacNAc-based substrates

• DOI: 10.1016/j.apsb.2021.12.013
• Publication Date: 2021-12-24T08:34:41Z
• Authors: Wei Shi; Wanzhen Li; Jianxin Zhang; Tiehai Li; Yakai Song; Yue Zeng; Qian Dong; Zeng Lin; Likun Gong; Shuquan Fan; Feng Tang; Wei Huang
• Keywords: Bioorthogonal Chemistry; Conjugate

Glycosite-specific antibody‒drug conjugatess (gsADCs), harnessing Asn297 N-glycan of IgG Fc as the conjugation site for drug payloads, usually require multi-step glycoengineering with two or more enzymes, which limits substrate diversification and complicates preparation process. Herein, we report a series novel disaccharide-based substrates, reprogram to one-step synthesis gsADCs, catalyzed by an endo-N-acetylglucosaminidase (ENGase) Endo-S2. via ENGases has steps: deglycosylation wild-type (WT) transglycosylation mutated ENGases. But in current method, have found that disaccharide LacNAc oxazoline can be efficiently assembled onto WT Endo-S2 without hydrolysis product, enables directly from native antibodies. Further studies on specificity revealed this approach excellent tolerance various modification 6-Gal motif LacNAc. Within 1 h, gsADC was achieved using LacNAc-toxin substrates including structures free bioorthogonal groups. These gsADCs demonstrated good homogeneity, buffer stability, vitro vivo anti-tumor activity. This work presents strategy LacNAc-based manner highly efficient gsADCs.