3MBE:
reference: The diabetogenic mouse MHC class II molecule I-Ag7 is endowed with a switch that modulates TCR affinity., Yoshida K, Corper AL, Herro R, Jabri B, Wilson IA, Teyton L, J Clin Invest. 2010 May 3;120(5):1578-90. doi: 10.1172/JCI41502. Epub 2010, Apr 19. PMID: 20407212

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