By Richard Mitchell, MD, PhD, Associate Professor of Pathology, Harvard Medical School, Boston, MA
Vinay Kumar, MBBS, MD, FRCPath, Professor and Chairman, Department of Pathology, University of Chicago, Pritzker School of Medicine, Chicago, IL
Nelson Fausto, MD, Professor and Chair, Department of Pathology, University of Washington, Seattle, WA
Abul K. Abbas, MBBS, Professor and Chair, Department of Pathology, University of California San Francisco School of Medicine, San Francisco, CA and Jon Aster, MD, Brigham & Women's Hospital, Boston, MA