1. Department of Pathology, Microbiology & Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
2. Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN 37232, USA
3. The Vanderbilt Vaccine Center; Vanderbilt University Medical Center, Nashville, TN 37232, USA
4. Department of Pathology, Microbiology & Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA.