Badhwar AmanPreet, Hirschberg Yael, Tamayo Natalia Valle, Iulita M Florencia, Udeh-Momoh Chinedu T, Matton Anna, Tarawneh Rawan M, Rissman Robert A, Ledreux Aurélie, Winston Charisse N, Haqqani Arsalan S
bioRxiv. 2023 Oct 2:2023.10.02.560210. doi: 10.1101/2023.10.02.560210.
Brain-derived extracellular vesicles (BEVs) in blood allows for minimally- invasive investigations of CNS-specific markers of age-related neurodegenerative diseases (NDDs). Polymer-based EV- and immunoprecipitation (IP)-based BEV-enrichment protocols from blood have gained popularity. We systematically investigated protocol consistency across studies, and determined CNS-specificity of proteins associated with these protocols.
NDD articles investigating BEVs in blood using polymer-based and/or IP-based BEV enrichment protocols were systematically identified, and protocols compared. Proteins used for BEV-enrichment and/or post-enrichment were assessed for CNS- and brain-cell-type- specificity; extracellular domains (ECD+); and presence in EV-databases.
82.1% of studies used polymer-based (ExoQuick) EV-enrichment, and 92.3% used L1CAM for IP-based BEV-enrichment. Centrifugation times differed across studies. 26.8% of 82 proteins systematically identified were CNS-specific: 50% ECD+, 77.3% were listed in EV- databases.
We identified protocol steps requiring standardization, and recommend additional CNS-specific proteins that can be used for BEV-enrichment or as BEV-biomarkers.
血液中的脑源性细胞外囊泡（BEV）有助于对年龄相关性神经退行性疾病（NDD）的中枢神经系统特异性标志物进行微创研究。基于聚合物的细胞外囊泡富集方案以及基于免疫沉淀（IP）的血液中BEV富集方案越来越受欢迎。我们系统地研究了各研究间方案的一致性，并确定了与这些方案相关的蛋白质的中枢神经系统特异性。
系统识别使用基于聚合物和/或基于IP的BEV富集方案研究血液中BEV的NDD文章，并比较各方案。评估用于BEV富集和/或富集后的蛋白质的中枢神经系统和脑细胞类型特异性、细胞外结构域（ECD+）以及在细胞外囊泡数据库中的存在情况。
82.1%的研究使用基于聚合物的（ExoQuick）细胞外囊泡富集方法，92.3%的研究使用L1CAM进行基于IP的BEV富集。各研究的离心时间不同。系统鉴定的82种蛋白质中有26.8%是中枢神经系统特异性的：50%具有细胞外结构域，77.3%列于细胞外囊泡数据库中。
我们确定了需要标准化的方案步骤，并推荐了可用于BEV富集或作为BEV生物标志物的其他中枢神经系统特异性蛋白质。
