MATERIALS: One 4 ml yellow top SST Gel and Clot Activator SERUM tube (BD Franklin Lakes, NJ., Ref# 367977) PROTOCOL: After centrifugation, pipette 500 uL of the liquid phase above the formed clot into each of the four tubes labeled “SE-01, SE-02, etc.” Avoid contaminating the sample by preventing the pipette tip from touching the wax that the serum sits upon. Tipping of the tube can ease the access to the remaining serum volume that sits on top of the wax layer. The remainder of the tube can be discarded.
Freezers are divided into 4 shelves, with 6 racks per shelf, and 24 boxes that can be held in each shelf. In total, 576 boxes, approximately 2,160 sample sets, can be stored in one -80°C freezer. The first three shelves are designated by visit number: Shelves A1-6 (top shelf) house samples from enrollment visits, shelves B1-6 (2nd shelf) house samples from the 1st year follow-up, and shelves C1-6 (3rd shelf) house samples from the 2nd year follow-up. Shelves D1-6 contain packed red blood cell tubes (PRBC), DNA, and RNA, extracted from blood as described in the protocols above. CSF is designated between two freezers in selected racks. Freezer storage and transactions of samples are recorded in the Freezerworks Inventory software.