Biological Samples

Standardized preanalytical handling by trained personnel is presented as improving the reliability of stored material. Saliva was collected at five time points across the waking day. Up to eight cerebrospinal fluid aliquots of 500 microlitres were stored at -80°C. Cerebrospinal fluid was collected by lumbar puncture in three consecutive 2 mL fractions using polypropylene tubes. Blood samples were collected in K2 EDTA and serum tubes, centrifuged within 2 hours, and stored as serum, plasma, and buffy coat aliquots. The second cerebrospinal fluid fraction was centrifuged within 2 hours and analyzed for routine diagnostic biomarkers. Peripheral blood is processed into plasma and peripheral blood mononuclear cells for storage. Blood draws were scheduled from 06:00 to 10:00 to control for circadian variation in biomarkers. Tumour tissue and adjacent normal breast tissue are collected and preserved using standardised procedures when available. Participants were required to have recent night shift exposure before sampling so biomarkers reflected shift exposure rather than recovery. ODIN stores paired cerebrospinal fluid and blood samples. The samples will support future translational res…