From mechanisms to therapeutics: The expanding role of cell-based strategies in Alzheimer's disease.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by cognitive decline. Its core pathologies include the deposition of amyloid-β plaques, the formation of neurofibrillary tangles composed of hyperphosphorylated tau protein, chronic neuroinflammation, and neuronal loss. With the rapidly aging global population, the prevalence of AD continues to rise. Current pharmacological treatments offer only limited symptomatic relief and cannot modify the underlying disease trajectory, leaving a significant unmet clinical need. In this context, cell-based therapy has emerged as a promising therapeutic strategy, leveraging its unique multi-targeted and regenerative capacities. This review systematically examines the therapeutic potential of various cell types, including mesenchymal stem cells, neural stem cells, immune cells, and engineered cells. We elaborate on their mechanisms of action, which encompass neurotrophic support, immunomodulation, and clearance of pathological proteins. These concerted actions contribute to remodeling the hostile brain microenvironment and promoting neuroregeneration in AD. Although preclinical evidence is robust, the clinical translation of cellular therapies faces considerable challenges. These hurdles include selecting the optimal cell source, developing efficient delivery strategies, determining the ideal intervention timing, and establishing standardized manufacturing protocols. Looking forward, we discuss how the development of precise disease models, the integration of gene editing and engineering strategies, advances in combination therapies, and the establishment of personalized treatment regimens are poised to position cell therapy at the forefront of comprehensive AD management. These innovations hold new promise for achieving true disease modification.