Vaccine and Infectious Diseases and Public Health Sciences Divisions, Fred Hutchinson Cancer Research Center, Seattle, WA 98109-1024, USA.|Vaccine and Infectious Diseases and Public Health Sciences Divisions, Fred Hutchinson Cancer Research Center, Seattle, WA 98109-1024, USA.|Vaccine and Infectious Diseases and Public Health Sciences Divisions, Fred Hutchinson Cancer Research Center, Seattle, WA 98109-1024, USA.|Vaccine and Infectious Diseases and Public Health Sciences Divisions, Fred Hutchinson Cancer Research Center, Seattle, WA 98109-1024, USA.|Vaccine and Infectious Diseases and Public Health Sciences Divisions, Fred Hutchinson Cancer Research Center, Seattle, WA 98109-1024, USA.