4I18:
reference: Engineering synthetic antibody binders for allosteric inhibition of prolactin receptor signaling., Rizk SS, Kouadio JL, Szymborska A, Duguid EM, Mukherjee S, Zheng J, Clevenger CV, Kossiakoff AA, Cell Commun Signal. 2015 Jan 15;13(1):1. PMID: 25589173

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