Labra Sergio R, Compher Jadon, Prabhavalkar Akhil, Almaraz Mireya, Kwong Claudia Cedeño, Baal Christine, Talantova Maria, Dolatabadi Nima, Piña-Sanz Julian, Wang Yubo, Yoon Leonard, Ghatak Swagata, Gao Zi, Zhang Yuting, Trudler Dorit, Massey Lynee, Lin Wei, Balistreri Anthony, Bula Michael, Schork Nicholas J, Mondala Tony S, Head Steven R, Kelly Jeffery W, Lipton Stuart A
Neurodegeneration New Medicines Center, The Scripps Research Institute, La Jolla, CA, USA.
Department of Molecular and Cellular Biology, The Scripps Research Institute, La Jolla, CA, USA.
bioRxiv. 2025 Jul 8:2025.06.25.661453. doi: 10.1101/2025.06.25.661453.
Alzheimer's disease (AD) is the most common form of dementia worldwide. Despite extensive progress, the cellular and molecular mechanisms of AD remain incompletely understood, partially due to inadequate disease models. To illuminate the earliest changes in hereditary (familial) Alzheimer's disease, we developed an isogenic AD cerebrocortical organoid (CO) model. Our refined methodology produces COs containing excitatory and inhibitory neurons alongside glial cells, utilizing established isogenic wild-type and diseased human induced pluripotent stem cells (hiPSCs) carrying heterozygous familial AD mutations, namely PSEN1, PSEN1, or APP. Our CO model reveals time-progressive accumulation of amyloid beta (Aβ) species, loss of monomeric Tau, and accumulation of aggregated high-molecular-weight (HMW) phospho(p)-Tau species. This is accompanied by neuronal hyperexcitability, as observed in early human AD cases on electroencephalography (EEG), and synapse loss. Single-cell RNA-sequencing analyses reveal significant differences in molecular abnormalities in excitatory vs. inhibitory neurons, helping explain AD clinical phenotypes. Finally, we show that chronic dosing with autophagy activators, including a novel CNS-penetrant mTOR inhibitor-independent drug candidate, normalizes pathologic accumulation of Aβ and HMW p-Tau, normalizes hyperexcitability, and rescues synaptic loss in COs. Collectively, our results demonstrate these COs are a useful human AD model suitable for assessing early features of familial AD etiology and for testing drug candidates that ameliorate or prevent molecular AD phenotypes.
阿尔茨海默病（AD）是全球最常见的痴呆形式。尽管取得了广泛进展，但AD的细胞和分子机制仍未完全了解，部分原因是疾病模型不完善。为了阐明遗传性（家族性）阿尔茨海默病的最早变化，我们开发了一种同基因AD脑皮质类器官（CO）模型。我们改进的方法利用携带杂合家族性AD突变（即PSEN1、PSEN1或APP）的已建立的同基因野生型和患病人类诱导多能干细胞（hiPSC），生成包含兴奋性和抑制性神经元以及神经胶质细胞的CO。我们的CO模型揭示了淀粉样β（Aβ）物种的时间进展性积累、单体Tau的丧失以及聚集的高分子量（HMW）磷酸化（p）-Tau物种的积累。这伴随着神经元过度兴奋，如在早期人类AD病例的脑电图（EEG）中观察到的那样，以及突触丧失。单细胞RNA测序分析揭示了兴奋性神经元与抑制性神经元在分子异常方面的显著差异，有助于解释AD的临床表型。最后，我们表明，用自噬激活剂长期给药，包括一种新型的可穿透中枢神经系统的非mTOR抑制剂药物候选物，可以使Aβ和HMW p-Tau的病理积累正常化，可以使过度兴奋正常化，并挽救CO中的突触丧失。总的来说，我们的结果表明，这些CO是一种有用的人类AD模型，适用于评估家族性AD病因的早期特征以及测试改善或预防分子AD表型的候选药物。
