News Release

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

Peer-Reviewed Publication

Compuscript Ltd

In this new article publication from Acta Pharmaceutica Sinica B, authors Wei Shi, Wanzhen Li, Jianxin Zhang and colleagues from Shanghai Institute of Materia Medica Chinese Academy of Sciences, Shanghai, China,  Hangzhou Institute of Advanced Study, Hangzhou, China, University of Chinese Academy of Sciences, China, Nanjing University of Chinese Medicine, Nanjing, China and Liaocheng University, Liaocheng, China discuss one-step synthesis of site-specific antibody–drug conjugates by reprograming IgG glycoengineering with LacNAc-based substrates.

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 the substrate diversification and complicates the preparation process.

In this article the authors report a series of novel disaccharide-based substrates, which reprogram the IgG glycoengineering to one-step synthesis of gsADCs, catalyzed by an endo-N-acetylglucosaminidase (ENGase) of Endo-S2.


IgG glycoengineering via ENGases usually has two steps: deglycosylation by wild-type (WT) ENGases and transglycosylation by mutated ENGases. But in the current method, the authors have found that disaccharide LacNAc oxazoline can be efficiently assembled onto IgG by WT Endo-S2 without hydrolysis of the product, which enables the one-step glycoengineering directly from native antibodies.


Further studies on substrate specificity revealed that this approach has excellent tolerance on various modification of 6-Gal motif of LacNAc. Within 1 h, one-step synthesis of gsADC was achieved using the LacNAc-toxin substrates including structures free of bioorthogonal groups. These gsADCs demonstrated good homogeneity, buffer stability, in vitro and in vivo anti-tumor activity.


This work presents a novel strategy using LacNAc-based substrates to reprogram the multi-step IgG glycoengineering to a one-step manner for highly efficient synthesis of gsADCs.


Article reference: Wei Shi, Wanzhen Li, Jianxin Zhang, Tiehai Li, Yakai Song, Yue Zeng, Qian Dong, Zeng Lin, Likun Gong, Shuquan Fan, Feng Tang, Wei Huang, One-step synthesis of site-specific antibody–drug conjugates by reprograming IgG glycoengineering with LacNAc-based substrates,

Acta Pharmaceutica Sinica B, Volume 12, Issue 5, 2022, Pages 2417-2428, ISSN 2211-3835,

Keywords: Site-specific ADCs; ENGase; LacNAc; One-step assembly; Potent in vivo efficacy

Graphical Abstract: available at

A LacNAc-based substrate reprograms the multi-step IgG glycoengineering and enables the efficient one-step synthesis of glycosite-specific antibody–drug conjugates (gsADCs), catalyzed by a wild-type endo-glycosidase (Endo-S2). This method also facilitates diverse modification of biotinylation, fluorescent labeling, extra glycan elongation, etc. for gain of functions.

# # # # # #

The Journal of the Institute of Materia Medica, the Chinese Academy of Medical Sciences and the Chinese Pharmaceutical Association.

For more information please visit

Editorial Board:


APSB is available on ScienceDirect (


Submissions to APSB may be made using Editorial Manager® (


CiteScore: 12.5

Impact Factor: 11.614

JIF without self-citation: 10.746


ISSN 2211-3835

 # # # # #

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.