Domert Jakob, Sackmann Christopher, Severinsson Emelie, Agholme Lotta, Bergström Joakim, Ingelsson Martin, Hallbeck Martin
Department of Clinical Pathology and Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden.
Department of Public Health/Geriatrics, Rudbeck Laboratory, Uppsala University,Uppsala,Sweden.
PLoS One. 2016 Dec 28;11(12):e0168700. doi: 10.1371/journal.pone.0168700. eCollection 2016.
Parkinson's disease and other alpha-synucleinopathies are progressive neurodegenerative diseases characterized by aggregates of misfolded alpha-synuclein spreading throughout the brain. Recent evidence suggests that the pathological progression is likely due to neuron-to-neuron transfer of these aggregates between neuroanatomically connected areas of the brain. As the impact of this pathological spreading mechanism is currently debated, we aimed to investigate the transfer and subcellular location of alpha-synuclein species in a novel 3D co-culture human cell model based on highly differentiated SH-SY5Y cells. Fluorescently-labeled monomeric, oligomeric and fibrillar species of alpha-synuclein were introduced into a donor cell population and co-cultured with an EGFP-expressing acceptor-cell population of differentiated neuron-like cells. Subsequent transfer and colocalization of the different species were determined with confocal microscopy. We could confirm cell-to-cell transfer of all three alpha-synuclein species investigated. Interestingly the level of transferred oligomers and fibrils and oligomers were significantly higher than monomers, which could affect the probability of seeding and pathology in the recipient cells. Most alpha-synuclein colocalized with the lysosomal/endosomal system, both pre- and postsynaptically, suggesting its importance in the processing and spreading of alpha-synuclein.
帕金森病和其他α-突触核蛋白病是进行性神经退行性疾病，其特征是错误折叠的α-突触核蛋白聚集体在大脑中扩散。最近的证据表明，病理进展可能是由于这些聚集体在大脑神经解剖学连接区域之间的神经元到神经元的转移。由于这种病理传播机制的影响目前存在争议，我们旨在研究α-突触核蛋白物种在基于高度分化的SH-SY5Y细胞的新型三维共培养人类细胞模型中的转移和亚细胞定位。将荧光标记的α-突触核蛋白单体、寡聚体和纤维状物种引入供体细胞群体，并与表达EGFP的分化神经元样细胞受体细胞群体共培养。随后用共聚焦显微镜确定不同物种的转移和共定位。我们可以证实所研究的所有三种α-突触核蛋白物种的细胞间转移。有趣的是，转移的寡聚体和纤维以及寡聚体的水平明显高于单体，这可能会影响受体细胞中种子形成和病理的概率。大多数α-突触核蛋白在突触前和突触后都与溶酶体/内体系统共定位，这表明其在α-突触核蛋白的加工和传播中的重要性。
