1. From the Section of Neurosurgery, Department of Surgery, University of Chicago Medicine and Biological Sciences, IL (R.G., H.A.Z., J.K., M.D.F., Y.C., C.S., T.M., R.L., A.S., K.C., S.P., R.S., I.A.A.)
2. Cytometry and Antibody Technology, Biological Sciences Division, Office of Shared Research Facilities, University of Chicago, IL (R.D., D.L.)
3. Division of Cardiology, Department of Medicine (K.J.W., D.Y.L.), University of Utah School of Medicine, Salt Lake City.