Effect of Fc core fucosylation and light chain isotype on IgG1 flexibility

Simona Saporiti1, Tommaso Laurenzi1, Uliano Guerrini1

  • 1Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Via Balzaretti, 9, 20133, Milan, Italy.

N-glycosylation plays a key role in modulating the bioactivity of monoclonal antibodies (mAbs), as well as the light chain (LC) isotype can influence their physicochemical properties. However, investigating the impact of such features on mAbs conformational behavior is a big challenge, due to the very high flexibility of these biomolecules. In this work we investigate, by accelerated molecular dynamics (aMD), the conformational behavior of two commercial immunoglobulins G1 (IgG1), representative of κ and λ LCs antibodies, in both their fucosylated and afucosylated forms. Our results show, through the identification of a stable conformation, how the combination of fucosylation and LC isotype modulates the hinge behavior, the Fc conformation and the position of the glycan chains, all factors potentially affecting the binding to the FcγRs. This work also represents a technological enhancement in the conformational exploration of mAbs, making aMD a suitable approach to clarify experimental results.

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