1. Tulane National Primate Research Center, Tulane University School of Medicine, Covington, Louisiana, USA
2. Department of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
3. Aaron Diamond AIDS Research Center, Columbia University Vagelos College of Physicians and Surgeons, New York, New York, USA
4. Department of Pathology, Immunology and Laboratory Medicine, Rutgers University-New Jersey Medical School, Newark, New Jersey, USA