1 Lymphocyte Biology Section and Center for Advanced Tissue Imaging, Laboratory of Immune System Biology, NIAID, NIH, Bethesda, MD, USA. andrea.radtke@nih.gov.
2 Division of Scientific Categorization and Analysis, Office of Research Reporting and Analysis, Office of Extramural Research, Office of the Director, National Institutes of Health, Bethesda, MD, USA.
3 Division of Cardiovascular Sciences, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
4 Division of Cardiovascular Sciences, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA. zorina.galis@nih.gov.