作者单位:Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA[1]The Wistar Institute, Philadelphia, PA 19104, USA[2]Department of Biology, Drexel University, 3245 Chestnut Street, Philadelphia, PA 19104, USA[3]Department of Microbiology, University of Pennsylvania Perelman School of Medicine, 3610 Hamilton Walk, Philadelphia, PA 19104, USA[4]