Deciphering T Cell Dynamics in Alzheimer's Disease Pathogenesis: Insights and Implications

Neuroinflammation has emerged as a crucial factor in the pathogenesis of Alzheimer's disease (AD), paving the way for promising therapeutic interventions. Increasing evidence highlights the interplay between the peripheral immune system and the central nervous system (CNS) in driving neuroinflammation, with T lymphocytes playing a vital role in both regulatory and effector functions. Aberrant activation of T cells during the early stages of neuroinflammation perpetuates inflammatory responses by interacting with CNS glial cells and releasing pro-inflammatory mediators, such as IFN-γ, TNF-α, and IL-17. Studies have documented significant T cell activation and infiltration into the brain parenchyma in AD, contributing to disease progression. However, the specific mechanisms by which T cells mediate AD pathogenesis remain unclear. This comprehensive review synthesizes the current understanding of T cell involvement in AD pathology, emphasizing their aberrant activation, interactions with microglia, tau protein pathology, and the influence of gut microbiota. Finally, we propose potential treatment modalities for AD, highlighting the promise of T cell-based therapies currently under investigation in clinical trials. Understanding the critical role of T cells in intercellular communication and disease progression may enhance our comprehension of the pathophysiology of AD.