1. Inflammation Program, University of Iowa and Veterans Affairs Medical Center, Iowa City, IA 52241, U.S.A.
2. Department of Medicine, University of Iowa and Veterans Affairs Medical Center, Iowa City, IA 52241, U.S.A.
3. Department of Anatomy and Cell Biology, University of Iowa and Veterans Affairs Medical Center, Iowa City, IA 52241, U.S.A.
4. Department of Microbiology, Montana State University, Bozeman, MT 59717, U.S.A.
5. Wells Center for Pediatric Research, Department of Pediatrics (Hematology/Oncology), Microbiology/Immunology, and Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202, U.S.A.