Tag-free, specific conjugation of glycosylated IgG1 antibodies using microbial transglutaminase.

ABSTRACT: We present an efficient approach for tag-free, site-specific conjugation of a fully glycosylated antibody using microbial transglutaminase (mTG). We created variants of trastuzumab where a single surface-exposed residue of the human crystallizable fragment had been substituted to glutamine, with the objective of enabling site-specific mTG-mediated conjugation with primary amine payloads. MTG reactivity was determined by conjugation to an amino fluorophore, demonstrating effective tag-free conjugation at the newly introduced I253Q site. The conjugation of one payload per antibody heavy chain was confirmed by mass spectrometry. We further demonstrated two-step mTG/click chemistry-based conjugation of I253Q trastuzumab with monomethyl auristatin E. Cytotoxicity and specificity of the resultin

SUBMITTER: Hadjabdelhafid-Parisien A 

PROVIDER: S-EPMC9680618 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature