Autoantibodies in Alzheimer's disease: Multifaceted roles and therapeutic horizons.

BackgroundAlzheimer's disease (AD) is a neurodegenerative disorder characterized by pathogenesis involving numerous factors. Recent research has highlighted the significant role of autoimmunity in the initiation and progression of AD, with autoantibodies emerging as a pivotal area of investigation. Nevertheless, the influence of autoantibodies in AD is marked by substantial heterogeneity, they may either mitigate disease progression by clearing pathogenic protein aggregates or exacerbate the pathological process through mechanisms such as the activation of inflammatory responses or the induction of neuronal damage.ObjectiveThis review aims to synthesize the various roles of autoantibodies in AD, examine the factors that influence their functions, and assess their potential application in precision immunotherapy.MethodsPubMed and Web of Science databases were searched for English-language papers (2015-2025). Peer-reviewed human, animal and cell studies, systematic reviews and meta-analyses were screened independently by two reviewers.ResultsA total of 87 studies were selected for inclusion, spanning human, animal, and cellular research. The findings indicated that certain autoantibodies, such as those targeting amyloid-β, tau, or 4-hydroxynonenal, may confer neuroprotective effects. Conversely, other autoantibodies, including those against BACE1, aquaporin-4, or HuD, may exacerbate AD pathology. Importantly, some autoantibodies were found to exhibit dual roles, contingent upon their specific modifications or the context of the disease.ConclusionsAutoantibodies constitute a double-edged immune axis in AD. Their impact hinges on antigen class, disease stage, isotype affinity and glycosylation. Precision strategies-like CAAR-T cell therapy, glycosylation modulation, and affinity optimization-offer therapeutic promise but require further validation.