化学
磷酸化
τ蛋白
丝氨酸
胰蛋白酶
脑脊液
陶氏病
表位
生物化学
阿尔茨海默病
神经退行性变
神经科学
酶
疾病
抗体
病理
心理学
生物
免疫学
医学
作者
Anne‐Marie Jacobsen,Nico C. van de Merbel,Dorte Kornerup Ditlevsen,Ketil Tvermosegaard,Frank Schalk,Wietske Lambert,Christoffer Bundgaard,Jan T. Pedersen,Nina Rosenqvist
标识
DOI:10.1021/jasms.2c00324
摘要
Hyperphosphorylated tau protein is well-known to be involved in the formation of neurofibrillary tangles and the progression of age-related neurodegenerative diseases (tauopathies), including Alzheimer's Disease (AD). Tau protein phosphorylated at serine-396 (pS396-tau) is often linked to disease progression, and we therefore developed an analytical method to measure pS396-tau in cerebrospinal fluid (CSF) in humans and animal models of AD. In the S396-region, multiple phosphorylation sites are present, causing structural complexity and sensitivity challenges for conventional bottom-up mass spectrometry approaches. Here, we present an indirect LC-MS/MS method for quantification of pS396-tau. We take advantage of the reproducible miscleavage caused by S396 being preceded by a lysine (K395) and the proteolytic enzyme trypsin not cleaving when the following amino acid is phosphorylated. Therefore, treatment with trypsin discriminates between the forms of tau with and without phosphorylation at S396 and pS396-tau can be quantified as the difference between total S396-tau and nonphosphorylated S396-tau. To qualify the method, it was successfully applied for quantification of pS396-tau in human CSF from healthy controls and patients with Mild Cognitive Impairment and AD. In addition, the method was applied for rTg4510 mice where a clear dose dependent decrease in pS396-tau was observed in CSF following intravenous administration of a monoclonal antibody (Lu AF87908, hC10.2) targeting the tau epitope containing pS396. Finally, a formal validation of the method was conducted. In conclusion, this sensitive LC-MS/MS-based method for measurement of pS396-tau in CSF allows for quantitative translational biomarker applications for tauopathies including investigations of potential drug induced effects.
科研通智能强力驱动
Strongly Powered by AbleSci AI