1. From the Department of Pathology and Molecular Medicine and Department of Medicine, McMaster University, Hamilton, ON, Canada; Department of Statistics and Actuarial Science, University of Waterloo, Waterloo, ON, Canada; Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA; Department of Orthopedics, Surgical Sciences, Göteborg University, Göteborg, Sweden; and Institute for Immunology and Transfusion Medicine, Ernst-Moritz-Arndt University, Greifswald, Germany.