Plasma profiling of B lymphocyte-associated cytokines in Alzheimer's disease

BackgroundImmunological dysregulation is a hallmark of Alzheimer's disease (AD), a neurodegenerative disorder characterized by amyloid-β (Aβ) plaque accumulation and hyperphosphorylated Tau protein pathology. AD is associated with altered humoral immunity, which may play a role in its pathogenesis.ObjectiveThis study aimed to investigate alterations in plasma levels of B lymphocyte-associated cytokines and their clinical relevance in AD.MethodsWe performed quantitative detections of 13 cytokines associated with B lymphocytes (TNF-β, IL-13, IFN-γ, TNF-α, IL-2, BAFF, IL-6, CD40L, IL-10, IL-12p70, IL-4, IL-17A, and IL-7) in plasma and analyzed their associations with cognitive functions and biomarkers of AD.ResultsWe found that plasma levels of CD40L, BAFF, TNF-β, IL-6 and IL-17A were increased in AD patients. However, the plasma IL-10 concentrations were decreased in Aβ-PET⁺ subjects. Plasma levels of CD40L, BAFF, TNF-β, IL-6, IL-17A were negatively associated with the plasma Aβ_42/40 ratio. Plasma levels of IL-10 were negatively associated with pTau181. Plasma levels of BAFF were negatively associated with MMSE scores.ConclusionsThese findings demonstrate an altered B lymphocyte-associated cytokine secretion profile in AD patients, which correlates with the clinical severity and biomarkers of the disease.