Department of Public Health and Caring Sciences, Molecular Geriatrics, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden.
BioArctic AB, Warfvinges väg 35, SE-112 51, Stockholm, Sweden.
J Neuroinflammation. 2018 Mar 28;15(1):98. doi: 10.1186/s12974-018-1134-4.
Currently, several amyloid beta (Aβ) antibodies, including the protofibril selective antibody BAN2401, are in clinical trials. The murine version of BAN2401, mAb158, has previously been shown to lower the levels of pathogenic Aβ and prevent Aβ deposition in animal models of Alzheimer's disease (AD). However, the cellular mechanisms of the antibody's action remain unknown. We have recently shown that astrocytes effectively engulf Aβ protofibrils, but store rather than degrade the ingested Aβ aggregates. In a co-culture set-up, the incomplete degradation of Aβ protofibrils by astrocytes results in increased neuronal cell death, due to the release of extracellular vesicles, containing N-truncated, neurotoxic Aβ.
The aim of the present study was to investigate if the accumulation of Aβ in astrocytes can be affected by the Aβ protofibril selective antibody mAb158. Co-cultures of astrocytes, neurons, and oligodendrocytes, derived from embryonic mouse cortex, were exposed to Aβ protofibrils in the presence or absence of mAb158.
Our results demonstrate that the presence of mAb158 almost abolished Aβ accumulation in astrocytes. Consequently, mAb158 treatment rescued neurons from Aβ-induced cell death.
Based on these findings, we conclude that astrocytes may play a central mechanistic role in anti-Aβ immunotherapy.
目前,已有几种淀粉样蛋白 β(Aβ)抗体,包括原纤维选择性抗体 BAN2401,正在进行临床试验。BAN2401 的鼠源版本 mAb158 先前已被证明可降低致病性 Aβ 的水平并预防阿尔茨海默病(AD)动物模型中的 Aβ 沉积。然而,抗体作用的细胞机制仍不清楚。我们最近表明,星形胶质细胞可有效地吞噬 Aβ 原纤维,但会储存而不是降解吞噬的 Aβ 聚集体。在共培养设置中,星形胶质细胞对 Aβ 原纤维的不完全降解会导致神经元细胞死亡增加,这是由于含有 N 截断的、神经毒性 Aβ 的细胞外囊泡的释放。
本研究的目的是研究 Aβ 原纤维选择性抗体 mAb158 是否会影响星形胶质细胞中 Aβ 的积累。来自胚胎鼠皮层的星形胶质细胞、神经元和少突胶质细胞的共培养物在存在或不存在 mAb158 的情况下暴露于 Aβ 原纤维。
我们的结果表明,mAb158 的存在几乎消除了星形胶质细胞中 Aβ 的积累。因此,mAb158 处理可挽救神经元免受 Aβ 诱导的细胞死亡。
基于这些发现,我们得出结论,星形胶质细胞可能在抗 Aβ 免疫治疗中发挥核心机制作用。