Tobaldi Elisabetta, Dovgan Igor, Mosser Michel, Becht Jean-Michel, Wagner Alain
Laboratory of Biofunctional Chemistry, UMR 7199, Faculty of Pharmacy, 74 Route du Rhin, 67400 Illkirch, France.
Org Biomol Chem. 2017 Nov 15;15(44):9305-9310. doi: 10.1039/c7ob01757j.
The biochemical characteristics of hetero-bifunctional cross-linkers used in bioconjugates are of essential importance to the desired features of the final adduct (i.e. antibody-drug conjugates). These include stability in biological media, chemical and biological reactivities, cleavability under defined conditions, and solubility. In our previous work, we introduced a new amino-to-thiol linker, maleimidomethyl dioxane (MD), as an alternative to classical maleimide conjugation, with increased hydrophilicity and serum stability due to succinimidyl ring-opening. In this work, we investigate the generality of linkers containing a dioxo-ring with regard to their ability to self-hydrolyze and their surprising stability at a low pH. We synthesized four FRET probes which allowed us to address the stability of the dioxo-ring and to study the maleimide ring-opening and the thiol-exchange processes by means of detecting and measuring the generation of fluorescence. It was found that the ring expansion (from a 5- to a 6-membered ring) improved the stability of the probes in aqueous media, and the increase of the chain length between the dioxo-ring and the succinimide ring (from methylene to ethylene) decreased the rate of succinimidyl ring-opening.
生物偶联物中使用的异双功能交联剂的生化特性对于最终加合物（即抗体-药物偶联物）的理想特性至关重要。这些特性包括在生物介质中的稳定性、化学和生物反应活性、在特定条件下的可裂解性以及溶解性。在我们之前的工作中，我们引入了一种新的氨基到硫醇连接剂，马来酰亚胺甲基二氧六环（MD），作为经典马来酰亚胺共轭的替代物，由于琥珀酰亚胺开环，其亲水性和血清稳定性增加。在这项工作中，我们研究了含二氧环连接剂在自我水解能力以及在低pH下令人惊讶的稳定性方面的普遍性。我们合成了四种荧光共振能量转移（FRET）探针，通过检测和测量荧光的产生，使我们能够研究二氧环的稳定性，并研究马来酰亚胺开环和硫醇交换过程。结果发现，环扩张（从五元环到六元环）提高了探针在水性介质中的稳定性，二氧环与琥珀酰亚胺环之间链长的增加（从亚甲基到亚乙基）降低了琥珀酰亚胺开环的速率。
