1. Program in Immunology, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
2. Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
3. Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
4. Department of Medicine, University of Washington School of Medicine, Seattle, WA 98195, USA.