1. Graduate Program in Cell Biology and Physiology, University of Pennsylvania School of Medicine, Philadelphia, PA;
2. Center for Human Immunobiology, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX;
3. National Institute of Allergy and Infectious Diseases, National Institutes of Health, Laboratory of Clinical Infectious Disease, Bethesda, MD; and
4. Department of Pediatrics, Baylor College of Medicine, Texas Children’s Hospital, Houston, TX