Blood sampling and processing Fasting venous blood samples (BD Vacutainer® LH 17 I.U. 10 ml tube) are collected and stored at 4°C within 5 to 10 minutes. Around 8 hours after blood collection, blood samples are transported on crushed ice to the central laboratory and centrifuged at room temperature (swinging bucket centrifuge, 1600 g, 15 minutes). Subsequently, 4 plasma aliquots of 500 µl are transferred into sterile cryovials and stored at -80°C until examination within 6 months. When subjects give permission to store their biological material, 3 aliquots are stored at the University Biobank Limburg (UBiLim) for biomedical research purposes.