Tournier Benjamin B, Snoeijs Christophe, Tsartsalis Stergios, Amossé Quentin, Farchoukh Ramzi, Kövari Eniko, Ceyzériat Kelly, Millet Philippe
Department of Psychiatry, University Hospitals of Geneva, Switzerland.
Department of Psychiatry, University of Geneva, Switzerland.
Aging Brain. 2022 Jul 8;2:100045. doi: 10.1016/j.nbas.2022.100045. eCollection 2022.
Increase in the brain expression of the 18 kDa translocator protein (TSPO) is considered as a marker of neuroinflammation in the context of brain diseases, such as Alzheimer's disease (AD). However, in non-demented subjects with Alzheimer's neuropathology, TSPO accumulation in hippocampus subdivisions has not been fully characterized. To determine if TSPO is associated with the presence of amyloid β plaques and/or phosphorylated Tau accumulation, we analyzed hippocampal sections using immunohistochemistry of 14 non-demented subjects with positive staining for Aβ and/or phosphorylated Tau. TSPO expression was heterogenous with higher accumulation in the CA2/3 and subiculum subfields of the hippocampus. Its distribution closely resembled that of the microglial IBA1 marker and of the Aβ42 amyloid form. In addition, positive correlations were observed between TSPO and IBA1 densities in CA4, CA2/3 and the subiculum but not with either the astrocyte GFAP marker or the AD-type Aβ and Tau markers. This study sustains the hypothesis that TSPO is mainly associated with microglia and in Aβ42-rich subdivisions in the hippocampus of non-demented elderly individuals.
在诸如阿尔茨海默病（AD）等脑部疾病的背景下，18 kDa转位蛋白（TSPO）在大脑中的表达增加被视为神经炎症的标志物。然而，在具有阿尔茨海默病神经病理学特征的非痴呆受试者中，海马亚区TSPO的积累尚未得到充分表征。为了确定TSPO是否与淀粉样β斑块的存在和/或磷酸化Tau的积累相关，我们使用免疫组织化学方法分析了14例Aβ和/或磷酸化Tau染色呈阳性的非痴呆受试者的海马切片。TSPO表达具有异质性，在海马的CA2/3和下托亚区积累更高。其分布与小胶质细胞IBA1标志物和Aβ42淀粉样蛋白形式的分布非常相似。此外，在CA4、CA2/3和下托中观察到TSPO与IBA1密度之间呈正相关，但与星形胶质细胞GFAP标志物或AD型Aβ和Tau标志物均无相关性。本研究支持这样的假设，即TSPO主要与小胶质细胞以及非痴呆老年人海马中富含Aβ42的亚区相关。
