Author Information By Vinay Kumar MBBS MD FRCPath Donald N. Pritzker Professor and Chairman Department of Pathology Biologic Sciences Division and Pritzker School of Medicine The University of Chicago Chicago Illinois; Abul K. Abbas MBBS Distinguished Professor and Chair Department of Pathology University of California San Francisco San Francisco California and Jon C. Aster MD PhD Professor of Pathology Harvard Medical School; Brigham and Women's Hospital Boston Massachusetts