Table 3 CSF collection procedures and sample processing

Subjects:

13 neurosurgical patients carrying a CSF drainage

8 M, 5 F; 26 to 82 y

Admitted for tumor, trauma, hemorrhage (n = 9), CSF pressure monitoring (n = 4)

CSF collection:

From lumbar (n = 7) or ventricular (n = 6) drainage

Volume: 4 mL in PP Sarsted tubes, code: 62.610.201

Time of day: 8.00, 12.00, 16.00, 20.00, 00.00, 8.00

CSF processing:

Centrifugation within 15 min, 2000 g × 10 min at RT

0.5 mL aliquots in PP Sarsted tubes, code: 72.730.007

CSF storage:

−80 °C freezer, with controlled temperature, alarm and CO2 backup system

Thawing:

RT with gentle shaking

Biomarker measurement:

Immunoassay (Fujirebio): Aβ1-42, t-tau, p-tau181

Immunoassay (Biovendor): VILIP-1

Immunoassay (R&D): YKL-40

Immunoassay (Euroimmun): Aβ1-38, Aβ1-40, Aβ1-42, t-tau, ApoE

Immunoassay (in-house): neurogranin

Immunoassay (MSD): Aβx-38, Aβx-40, Aβx-42, sAPPα, sAPPβ