Plasma Inflammation Profiles Linked to Cognition via Distinct Pathways in Alzheimer's Disease
核心洞察
A multicenter study identified two distinct plasma inflammatory signatures in amyloid-positive AD/MCI patients using principal component analysis of cytokine profiles.
A proinflammatory component driven by TNF-α (搜索), IL-7, IL-17A (搜索), and CXCL5 (搜索) was directly associated with poorer cognition, independent of p-tau217 (搜索), NfL, and GFAP (搜索).
A second inflammatory profile linked to TNF receptor II (搜索), MIF (搜索), IL-16 (搜索), and CXCL10 (搜索) showed an indirect effect on cognition mediated through neurodegeneration as measured by plasma NfL.
A new study published in Alzheimer's & Dementia has identified two distinct plasma inflammation profiles in Alzheimer's disease (搜索) (AD) that relate to cognition through different biological pathways, offering potential tools for stratifying patients in future immunomodulatory therapeutic trials.
The research, drawn from the multicenter BioHermes cohort, analyzed 176 amyloid-positive individuals with AD or mild cognitive impairment (MCI) alongside 173 age- and sex-matched cognitively unimpaired controls. Using principal component analysis on Luminex-measured plasma cytokines, investigators derived inflammatory signatures and examined their direct and indirect associations with cognition and neurodegeneration.
Proinflammatory Component Directly Tied to Poorer Cognition
The first key finding centered on what researchers termed Proinflammatory Component 2, which was significantly elevated in participants with AD/MCI. This signature was driven by pro-inflammatory cytokines including TNF-α (搜索), IL-7, IL-17A (搜索), and CXCL5 (搜索), reflecting broader immune activation. Critically, the association between this component and poorer cognitive performance remained robust after adjusting for established AD biomarkers—phosphorylated tau 217 (p-tau217 (搜索)), neurofilament light (搜索) (NfL), and glial fibrillary acidic protein (GFAP (搜索))—indicating an independent pathway linking inflammation to cognitive decline.
Notably, higher levels of this proinflammatory profile were also observed in Black/African American participants, underscoring the importance of diverse cohort representation when developing and validating inflammatory biomarkers for clinical use.
Neurodegeneration-Mediated Pathway Identified
A second inflammatory profile, Inflammatory Component 1, showed a different pattern of association. Markers including TNF receptor II (搜索), macrophage migration inhibitory factor (MIF (搜索)), IL-16 (搜索), and CXCL10 (搜索) suggested a broader inflammatory-remodeling response. This component was linked to increased plasma NfL levels, a marker of neuroaxonal injury, which in turn was associated with poorer cognitive performance. The findings indicate that this inflammatory signature may contribute to cognitive decline indirectly, through neurodegeneration-mediated pathways.
Implications for Immunomodulatory Therapy Development
The study authors conclude that inflammatory signatures in AD are heterogeneous, with different immune profiles appearing to influence cognition through distinct mechanisms. Rather than a single inflammatory pathway driving disease progression, coordinated immune patterns may help explain variability in how the disease advances across patients.
Blood-based inflammatory panels, particularly when combined with established biomarkers such as NfL, could support patient stratification in future clinical trials evaluating immune-targeting treatments. The researchers note, however, that longitudinal studies incorporating imaging and additional biomarker approaches are needed to determine whether these inflammatory profiles can predict disease progression or treatment response over time.