1. Inflammation Drug Discovery Research, One Amgen Center Drive, Thousand Oaks, California 91320-1789;
2. Discovery Research Amgen Inc., One Amgen Center Drive, Thousand Oaks, California 91320-1789;
3. The Amgen Institute, Ontario Cancer Institute, and the Departments of Medical Biophysics and Immunology, University of Toronto, 620 University Avenue, Toronto, Ontario M5G 2C1, Canada