Cerebrospinal Fluid p-tau217-Guided Astrocyte-Derived Extracellular Vesicle Delivery of lncRNA-0021 in Early-Stage AD

CSF p-tau217 concentrations serve as a precision biomarker to optimize the therapeutic delivery of lncRNA-0021 through astrocyte-derived extracellular vesicles (ADEVs) rather than mesenchymal stem cell exosomes. The hypothesis proposes that astrocyte-derived vesicles demonstrate superior blood-brain barrier penetration and neurotropism compared to MSC exosomes, enabling more efficient lncRNA-0021 delivery to affected neural circuits during the critical Braak stage III-IV window when CSF p-tau217 levels peak but before irreversible synaptic loss occurs. ADEVs naturally express enhanced GLUT1 and transferrin receptor densities, facilitating transcytosis across brain endothelial cells and selective targeting of tau-accumulating neurons.

CSF p-tau217 concentrations serve as a precision biomarker to optimize the therapeutic delivery of lncRNA-0021 through astrocyte-derived extracellular vesicles (ADEVs) rather than mesenchymal stem cell exosomes. The hypothesis proposes that astrocyte-derived vesicles demonstrate superior blood-brain barrier penetration and neurotropism compared to MSC exosomes, enabling more efficient lncRNA-0021 delivery to affected neural circuits during the critical Braak stage III-IV window when CSF p-tau217 levels peak but before irreversible synaptic loss occurs. ADEVs naturally express enhanced GLUT1 and transferrin receptor densities, facilitating transcytosis across brain endothelial cells and selective targeting of tau-accumulating neurons. The CSF p-tau217-guided dosing protocol involves real-time monitoring of tau phosphorylation kinetics to determine optimal ADEV infusion timing and concentration gradients. This approach maximizes lncRNA-0021 bioavailability within the hippocampal-entorhinal network while maintaining the core therapeutic mechanism of miR-6361 sequestration restoration. The astrocyte-derived delivery system potentially offers improved pharmacokinetics through endogenous brain cell recognition pathways, reducing systemic distribution and minimizing peripheral off-target effects. Additionally, ADEVs may carry complementary neuroprotective factors naturally produced by astrocytes, creating a synergistic therapeutic environment that enhances lncRNA-0021 efficacy during the p-tau217-defined treatment window.