1. From the Department of Donor Studies (F.A., I.V., W.d.K., P.P.-d.J.), Sanquin Research, Nijmegen, the Netherlands; Unit of Medical Affairs (M.v.K.), Sanquin Blood Bank, Nijmegen, the Netherlands; Department of Internal Medicine (J.D.), Radboud University Nijmegen Medical Center, Nijmegen, the Netherlands.