1. B. A. Fields, E. L. Malchiodi, M. I. Lebedeva, B. C. Braden, R. A. Mariuzza, Center for Advanced Research in Biotechnology, University of Maryland Biotechnology Institute, 9600 Gudelsky Drive, Rockville, MD 20850, USA.
2. B. Ober, J.-K. Kim, X. Shao, E. S. Ward, Cancer Immunobiology Center and Department of Microbiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75235-8576, USA.
3. X. Ysern, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, 5600 Fishers Lane, Rockville, MD 20857, USA.