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Angelman syndrome is a neurodevelopmental disorder caused by (epi)genetic lesions of maternal UBE3A. Research has focused largely on the role of UBE3A in neurons due to its imprinting in that cell type. Yet, evidence suggests there may be broader neurodevelopmental impacts of UBE3A dysregulation. Human cerebral organoids might reveal these understudied aspects of UBE3A as they recapitulate diverse cell types of the developing human brain. In this study, scRNAseq on organoids reveals the effects of UBE3A disruption on cell type-specific compositions and transcriptomic alterations. In the absence of UBE3A, progenitor proliferation and structures are disrupted while organoid composition shifts away from proliferative cell types. We observe impacts on non-neuronal cells, including choroid plexus enrichment. Furthermore, EMX1+ cortical progenitors are negatively impacted; potentially disrupting corticogenesis and delaying excitatory neuron maturation. This work reveals impacts of UBE3A on understudied cell types and related neurodevelopmental processes and elucidates potential therapeutic targets. Human cerebral organoids exhibit compositional and transcriptomic alterations in both neuronal and non-neuronal cells in the absence of UBE3A.

Neurological damage caused by peripheral nerve injury can be devastating and is a common neurological disorder that, along with muscle disorders, reduces the quality of life. Neural crest cells (NCCs) are a transient cell population that occurs during embryogenesis, can differentiate into various cells upon transplantation, and has potential therapeutic effects on neurological diseases. However, there are limitations to cell therapy, such as uncontrolled differentiation and tumor formation. Extracellular vesicles (EVs), which are non-cellular potential therapeutic candidates, are nanosized membrane-bound vesicles. Studies have been reported using starch cells derived from neural cells, such as neural stem cells, because they are involved in cell-to-cell communication and carry a variety of bioactive molecules. We investigated the effects of EVs isolated from NCCs on neuronal cell death and inflammation. Additionally, we overexpressed the nerve growth factor (NGF), which is involved in neural cell growth and proliferation, in NCCs to further investigate the effects of EVs containing NGF. NCCoe-NGF-EVs showed neuroprotective and regenerative properties by modulating inflammatory pathway, promoting Schwann cell activation, and enhancing remyelination. In vitro studies on NCCoe-NGF-EVs suppressed pro-inflammatory cytokines and reduced oxidative stress-induced neuronal apoptosis through NF-?B pathway inhibition and ERK, AKT signal activation. We also evaluated the effect of EVs on neuropathy by performing in vivo study. Our results suggest that NCCoe-NGF-EV had neuroprotective effects by reducing neuronal apoptosis and promoting neuronal proliferation based on neurite outgrowth and anti-inflammation effects treated with NCCoe-NGF-EVs. In addition, NCCoe-NGF-EVs were protected muscle loss caused by peripheral nerve injury. NCCoe-NGF-EV induced regeneration of damaged nerves and inhibited cell death through anti-inflammatory effects. This study suggests the potential of NGF-enriched EVs as non-cellular therapeutic platform for peripheral neuropathies and other neuroinflammatory disorders.Graphical abstract Supplementary InformationThe online version contains supplementary material available at 10.1186/s40478-025-02033-9.

Extraembryonic mesoderm (ExM) is crucial for human development, yet its specification is poorly understood. Human embryonic stem cell (hESC)-based models, including embryoids and differentiated derivatives, are emerging as promising tools for studying ExM development. Despite this, the signaling mechanisms and developmental dynamics that underlie ExM specification from hESCs remain challenging to study. Here, we report that the modulation of BMP, WNT, and Nodal signaling pathways can rapidly (4-5 days) and efficiently (?~90%) induce the differentiation of both naive and primed hESCs into ExM-like cells (ExMs). We reveal that ExM specification from hESCs predominantly proceeds through intermediates exhibiting a primitive streak (PS)-like gene expression pattern and delineate the regulatory roles of WNT and Nodal signaling in this process. Furthermore, we find that the initial pluripotent state governs hESC-based ExM specification by influencing signal response, cellular composition, developmental progression, and transcriptional characteristics of the resulting ExMs. Our study provides promising models for dissecting human ExM development and sheds light on the signaling principles, developmental dynamics, and influences of pluripotency states underlying ExM specification from hESCs. Extraembryonic mesoderm (ExM) is crucial but its formation is unclear. Here, authors develop efficient systems to specify ExM from hESCs and dissect the signaling mechanisms, specification dynamics, and impact of pluripotent states in ExM formation.