%0 Journal Article %J J Alzheimers Dis %D 2016 %T Effect of Tween-20 on Core Biomarkers Measured in Cerebrospinal Fluid from Patients with Alzheimer's Disease, Mild Cognitive Impairment, or Healthy Control Individuals. %A Berge, Guro %A Lauridsen, Camilla %A Sando, Sigrid Botne %A Holder, Daniel Joseph %A Møller, Ina %A Aasly, Jan Olav %A Bråthen, Geir %A Savage, Mary Josephine %A White, Linda Rosemary %K Aged %K Alzheimer Disease %K Amyloid beta-Peptides %K Cognitive Dysfunction %K Enzyme-Linked Immunosorbent Assay %K Female %K Humans %K Longitudinal Studies %K Male %K Middle Aged %K Peptide Fragments %K Phosphorylation %K Polysorbates %K ROC Curve %K Surface-Active Agents %K tau Proteins %X

BACKGROUND: There is substantial variation caused by preanalytical procedures in the measurement of cerebrospinal fluid (CSF) biomarkers for Alzheimer's disease (AD) reported in the literature.

OBJECTIVE: Determine whether the detergent Tween-20 improves diagnostic accuracy.

METHODS: CSF proteins (Aβ42, Aβ40, total tau, and phosphorylated tau) were measured by standard ELISA, in uncentrifuged CSF with or without 0.05% Tween-20 from patients with AD or amnestic mild cognitive impairment, and healthy elderly controls. In the main study, collection tubes containing Tween-20 (Sarstedt 15 mL) were filled with 5 mL CSF to ensure consistent detergent concentration across subsequent aliquots into Corning 2 mL tubes. These latter were also the primary collection vessel for samples without Tween-20. The effect of centrifugation, and extra tube transfer of samples with Tween-20 were also examined.

RESULTS: 0.05% Tween-20 significantly increased mean measured CSF concentration of Aβ42 (30% ), Aβ40 (23% ), and total tau (4% ), but not phosphorylated tau. Generally, these increases were similar in all groups, although for Aβ42, the mean percentage increase with Tween-20 was slightly larger for AD. Areas under receiver-operator characteristic curves were similar whether Tween-20 was present or not. Centrifuged CSF without Tween-20 significantly reduced the measured concentration of Aβ42 versus non-centrifuged samples, a difference not seen when detergent was added. Similar CSF Aβ42 levels were found whether Tween-20 was added at collection in an extra tube or directly to the main collection tube.

CONCLUSION: Addition of Tween-20 to CSF did not improve differentiation of patients from controls.

%B J Alzheimers Dis %V 49 %P 493-502 %8 2016 %G eng %N 2 %1 http://www.ncbi.nlm.nih.gov/pubmed/26484901?dopt=Abstract %R 10.3233/JAD-150234