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bioRxiv · 10.1101/2025.03.03.641048

Structural basis of ZP2-targeted immunocontraception

Dioguardi, E.·Stsiapanava, A.·Fahrenkamp, E.·Han, L.·de Sanctis, D.·Inzunza, J.·Jovine, L.
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Abstract

Monoclonal antibody IE-3 prevents mouse fertilization by binding ZP2, a major component of the oocyte-specific zona pellucida (ZP). We show that an IE3-derived single-chain variable fragment (scFV) is sufficient for blocking fertilization in vitro and determine the structural basis of IE-3/ZP2 recognition. The high-affinity of this interaction depends on induced fit of the epitope, offering insights for non-hormonal immunocontraceptive design without off-target effects.

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Dioguardi, E., Stsiapanava, A., Fahrenkamp, E., Han, L., de Sanctis, D., Inzunza, J., Jovine, L.. 2025-03-06. Structural basis of ZP2-targeted immunocontraception. https://doi.org/10.1101/2025.03.03.641048

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