EXOGENOUS INDUCTION OF ALZHEIMER A?-PATHOLOGY IN TRANSGENIC MICE

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 我们研究了阿尔茨海默病患者和松鼠猴的数量和质量特征，松鼠猴是一种近缘关系密切但抗AD的灵长类物种。通过酶联免疫吸附试验，我们发现老年松鼠猴大脑皮质中的Aβ水平可以等于或超过AD脑中的水平。利用免疫沉淀和MALDI-TOF质谱仪，我们还表明，在患有AD的松鼠猴子和人类中，可溶和不可溶的A？肽群体高度相似。 为了验证这两个物种中的A？多聚体可能在病理性上呈现不同形式的假设，我们随后检测了来自松鼠猴子和AD患者的富含A？的皮质提取物在APP/PS1转基因小鼠中诱导或种子A？沉积的能力。将稀释的皮质提取物单侧注射到APP/PS1小鼠的海马区，然后在该区域内源性沉积A？对侧大脑半球注射假PBS作为内对照。在4个月的潜伏期后，对小鼠的大脑进行免疫组织化学染色。在所有实验动物注射提取物的大脑半球，A型沉积均增强。用双重免疫荧光和共聚焦显微镜，我们鉴定了AD和松鼠猴提取物所特有的种子A？沉积的细胞和实质模式。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. We have examined the quantitative and qualitative characteristics of A¿ in humans with AD and in squirrel monkeys (Saimiri sciureus), a closely related, but AD-resistant, primate species. By ELISA, we found that cortical A¿ levels in aged squirrel monkeys can equal or exceed the levels in AD brain. Using immunoprecipitation and MALDI-TOF mass spectrometry, we have also shown that soluble and insoluble A¿ peptide populations are highly similar in squirrel monkeys and humans with AD. To test the hypothesis that A¿-multimers in the two species may assume pathogenically dissimilar forms, we then examined the ability of A¿-rich cortical extracts from squirrel monkeys and AD patients to induce, or seed, A¿ deposition in APP/PS1 transgenic mice. Dilute cortical extracts were injected unilaterally into the hippocampus of APP/PS1 mice, prior to the endogenous deposition of A¿ in that region. Sham PBS injections in the contralateral hemisphere served as internal controls. After a 4 month incubation period, the mouse brains were immunostained with antibodies to the A¿ peptide. A¿ deposition was enhanced in the extract-injected hemisphere of all experimental animals. With double immunofluorescence and confocal microscopy, we identified cellular and parenchymal patterns of seeded A¿ deposition unique to AD and squirrel monkey extracts.