4YQX:
reference: Antibodies to Interleukin-2 Elicit Selective T Cell Subset Potentiation through Distinct Conformational Mechanisms., Spangler JB, Tomala J, Luca VC, Jude KM, Dong S, Ring AM, Votavova P, Pepper M, Kovar M, Garcia KC, Immunity. 2015 May 19;42(5):815-25. doi: 10.1016/j.immuni.2015.04.015. PMID: 25992858

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