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Amyloid-β plaques may be reduced in advanced stages of cerebral amyloid angiopathy in the elderly.
淀粉样蛋白-β 斑块在老年人脑淀粉样血管病的晚期可能减少。
- 影响因子:2.09
- DOI:10.1111/neup.12662
- 作者列表:"Okamoto K","Amari M","Fukuda T","Suzuki K","Takatama M
- 发表时间:2020-06-17
Abstract
:We examined 29 cases in which cerebral amyloid angiopathy (CAA) was detected among routine aged autopsies. Most cases with severe CAA had many amyloid-β (Aβ) plaques in the occipital cortex. Nonetheless, two cases had few Aβ plaques with many small vessels and capillaries with CAA. In the two cases, severe CAA was widely distributed, except in the frontal lobes. Aβ deposits in capillaries often showed the characteristic pattern of dysphoric amyloid angiopathy. A few naked plaques were present. Although Aβ plaques were sparse near small vessels with CAA, there were many Aβ plaques distant from small vessels with CAA. Some of the remaining plaques had a moth-eaten appearance. Based on Aβ-positive star-like appearance and results of double immunohistochemistry for glial fibrillary acidic protein and Aβ1-42 , some astrocytes appeared to contain Aβ. Ionized calcium-binding adapter molecule 1 (Iba1)-positive microglia were scattered within the neuropil, with some present around small vessels with CAA. Iba1-positive microglia also seemed to phagocytose Aβ in several senile plaques by double immunostaining. Neurons and neurites identified with a monoclonal antibody against phosphorylated tau (clone AT8) were occasionally detected in sparse plaque areas, with AT8-identified dot-like structures present around capillaries with CAA. Accumulation of T lymphocytes was detected around vessels in the subarachnoid space in one case. The morphological changes detected in our two cases were similar to those of morphological markers of plaque clearance after Aβ immunotherapy. Nonetheless, our cases did not receive Aβ immunotherapy, but similar pathologies were observed. Overall, advanced CAA cases, including our two cases, may be examples of plaque clearance without Aβ immunotherapy. Further studies are needed to resolve the mechanism of Aβ plaque clearance using these cases.
摘要
: 我们检查了 29 例常规老年尸检中检出脑淀粉样血管病 (CAA) 的病例。大多数严重 CAA 的病例在枕叶皮质有许多淀粉样蛋白-β (a β) 斑块。尽管如此,2 例有少量 a β 斑块,有多条小血管和毛细血管伴 CAA。2 例中重度 CAA 分布广泛,额叶除外。毛细血管内 a β 沉积常表现为烦躁不安的淀粉样血管病变的特征性模式。有一些裸露的斑块。虽然 a β 斑块在 CAA 小血管附近稀疏,但在 CAA 小血管附近有许多 a β 斑块。剩余的一些斑块有虫蛀的外观。基于 a β 阳性的星形细胞样外观和胶质纤维酸性蛋白和 a β 1-42 的双重免疫组化结果,一些星形胶质细胞似乎含有 a β。离子钙结合适配器分子 1 (Iba1) 阳性小胶质细胞散在 neuropil 内,一些存在于 CAA 小血管周围。通过双重免疫染色,Iba1-positive 小胶质细胞似乎也吞噬了几种老年斑中的 a β。偶尔在稀疏斑块区域检测到用磷酸化 tau (克隆 AT8) 单克隆抗体鉴定的神经元和神经突,CAA 毛细血管周围存在 AT8-identified 点状结构。1 例检测到蛛网膜下腔血管周围 T 淋巴细胞聚集。我们两例中检测到的形态学变化与 a β 免疫治疗后斑块清除的形态学标志物相似。尽管如此,我们的病例没有接受 a β 免疫治疗,但观察到类似的病理。总体而言,晚期 CAA 病例,包括我们的两例,可能是无 a β 免疫治疗的斑块清除的例子。使用这些病例需要进一步的研究来解决 a β 斑块清除的机制。
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