α-Synuclein (α-syn) accumulates as insoluble amyloid but also forms soluble α-syn oligomers (αSOs), thought to be even more cytotoxic than fibrils. To detect and block the unwanted activities of these αSOs, we have raised 30 monoclonal antibodies (mAbs) against different forms of αSOs, ranging from unmodified αSOs to species stabilized by lipid peroxidation products and polyphenols, αSOs formed by C-terminally truncated α-syn, and multivalent display of α-syn on capsid virus-like particles (cVLPs). While the mAbs generally show a preference for αSOs, they also bind fibrils, but to variable extents. Overall, we observe great diversity in the mAbs’ relative affinities for monomers and αSOs, varied requirements for the C-terminal extension of α-syn, and only a modest effect on α-syn fibrillation. Several mAbs show several orders of magnitude preference for αSOs over monomers in in-solution studies, while the commercial antibody MJF14 only bound 10-fold more strongly to αSOs than monomeric α-syn. Gratifyingly, seven mAbs almost completely block αSO permeabilization of membrane vesicles. Five selected mAbs identified α-syn-related pathologies like Lewy bodies (LBs) and Lewy Neurites, as well as Glial Cytoplasmic Inclusions in postmortem brains from people diagnosed for PD, dementia with LBs or multiple system atrophy, although to different extents. Three mAbs were particularly useful for pathological evaluation of postmortem brain human tissue, including early stages of PD. Although there was no straightforward connection between the mAbs’ biophysical and immunohistochemical properties, it is encouraging that this comprehensive collection of mAbs able to recognize different aggregated α-syn species in vitro also holds diagnostic potential.

α-突触核蛋白 (α-syn) 以不溶性淀粉样蛋白的形式积累，但也会形成可溶性 α-syn 寡聚物 (αSO)，被认为比原纤维的细胞毒性更强。为了检测和阻止这些 αSO 的不需要的活性，我们针对不同形式的 αSO 制备了 30 种单克隆抗体 (mAb)，范围从未修饰的 αSO 到通过脂质过氧化产物和多酚稳定的物种，由 C 端截短的 α-syn 形成的 αSO ，以及衣壳病毒样颗粒 (cVLP) 上 α-syn 的多价展示。虽然单克隆抗体通常表现出对 αSO 的偏好，但它们也结合原纤维，但程度不同。总体而言，我们观察到 mAb 对单体和 αSO 的相对亲和力存在很大差异，对 α-syn C 末端延伸的要求不同，并且对 α-syn 纤维颤动的影响不大。在溶液研究中，多种 mAb 对 αSO 的偏好程度高于单体，而商业抗体 MJF14 对 αSO 的结合强度仅比单体 α-syn 强 10 倍。令人高兴的是，七种单克隆抗体几乎完全阻断膜囊泡的 αSO 通透作用。五种选定的 mAb 鉴定出与 α-syn 相关的病理，如路易体 (LB) 和路易神经突，以及诊断为 PD、LB 痴呆或多系统萎缩的人死后大脑中的神经胶质细胞质包涵体，尽管程度不同。三种单克隆抗体对于人体死后脑组织（包括 PD 的早期阶段）的病理学评估特别有用。尽管单克隆抗体的生物物理和免疫组织化学特性之间没有直接联系，但令人鼓舞的是，这种能够在体外识别不同聚集的 α-syn 种类的综合单克隆抗体也具有诊断潜力。