Table 2.
Comparison of CSF collection/processing protocols from ADNI and PPMI studies.
| ADNI | PPMI | |
|---|---|---|
| Initial collection | In 5-cc syringes (1481729, Fisher Scientific) if suction LP, or 7-cc polypropylene collection tubes (14–956- 1C, Fisher Scientific) if drip LP1 | In 3-ml plastic syringe (part of LP tray, A3772–24, Smiths medical), 1–2 mL transferred to cryovial for local laboratory testing, then in 6 ml polypropylene syringes (A3772–24, Smiths Medical) |
| Transfer | Directly from 5-cc syringes or with sterile transfer pipets (1371120, Fisher Scientific) from 7-cc collection tubes to 13 ml polypropylene transfer tubes (60.541.004, Sarstedt), the 1st 2 ml transferred to 2 cryovials (1050026, Fisher Scientific) for local laboratory testing |
To 15 ml conical polypropylene tubes (430701, Corning) |
| Processing at collection site | None. | Invert tubes 3–4 times, centrifuge (2,000 × g, 10 min, 4°C) within 15 minutes of collection, supernatant transferred to a new 15 ml conical polypropylene tube (430791, Corning), inverted 3–4 times, 1.5 ml aliquots in 2 ml pre-cooled polypropylene tubes (72.694.006, Sarstedt) |
| Freezing, shipping and storage | 13 ml transfer tubes frozen directly on dry ice as soon as possible and shipped | Aliquots frozen directly on dry ice within 60 minutes of collection, stored at −80°C or shipped on dry ice |
| Further processing at biodepository site | Samples in 13-mL tubes thawed at room temperature with gentle rotation, transferred to 30 ml polypropylene tubes (62.543.001, Sarstedt), mixed by gentle rotation for 5 minutes, 0.5 ml aliquoted in 0.5 ml polypropylene copolymer tubes (3428000005 & 3428210116, Fisher Scientici), aliquots transferred directly to −80°C | Pre-chill labeled 0.5 ml siliconized cryovials at −80°C. Thaw 1.5 ml CSF aliquots at 4°C. Transfer 0.5 ml tubes to dry ice. Mix 1.5 ml CSF aliquots by inverting the tube 6–8 times (not vortexing or mixing by pipette). Sub- aliquot 250 μl CSF into each pre-cooled tube. Transfer to −80°C freezer. |
| Long term storage | −80°C | −80°C |
| Analytical site processing | For Aβ and tau: thaw 0.5 ml sub-aliquots on ice before assay; For α-syn and pS129: thaw 0.5 ml sub-aliquots on ice, add 10% of protease inhibitor cocktail (10×), further sub-aliquot into 0.11-mL aliquots and frozen at −80°C. Thaw aliquots on ice before assay. |
Thaw 0.25 ml sub-aliquots on ice before assay |
1
The syringe method was used for all subjects in this study.