Akademik Veri Yönetim Sistemi
Acta Neurologica Belgica, 2026 (SCI-Expanded, Scopus)
Background: The soluble form of the Triggering Receptor Expressed on Myeloid Cells 2 (sTREM2) is an indicator of microglial activation linked to neurodegeneration. While CSF sTREM2 shows promise as an Alzheimer’s biomarker, the relevance of plasma sTREM2 across amyloid- and tau-defined biomarker profiles and across dementia subtypes remains unclear. We therefore assessed plasma sTREM2 levels across clinical dementia diagnoses, including Alzheimer’s disease, frontotemporal dementia, dementia with Lewy bodies, posterior cortical atrophy, Parkinson’s disease with mild cognitive impairment, and normal pressure hydrocephalus, as well as across cerebrospinal fluid amyloid- and tau-defined biomarker profiles, to clarify whether plasma sTREM2 reflects disease-specific pathology or broader immune-related changes associated with neurodegenerative conditions. Methods: ELISA was used to measure the levels of plasma sTREM2 in 27 cognitively normal controls and 56 dementia patients, including those with AD, FTD, and other dementias. Patients were stratified based on clinical diagnosis and the CSF amyloid and tau status. The associations between plasma sTREM2, CSF biomarkers, and cognitive performance were investigated through correlation analyses. Results: In the overall dementia group, plasma sTREM2 levels were significantly higher compared to the controls. The non-AD dementia group (FTD and other dementias) had significantly higher plasma sTREM2 levels compared to controls. Plasma sTREM2 concentrations were significantly higher in amyloid-negative (A−) and tau-negative (T−) patients than in controls. In the T− group, there was a positive correlation between plasma sTREM2 and CSF Aβ₁–₄₂. Conclusion: Our findings indicate that plasma sTREM2 may reflect peripheral immune processes, in the absence of classical AD pathology. Elevated TREM2 levels in biomarker-negative subgroups might indicate early microglial responses rather than neurodegeneration specific to a disease stage. Our findings highlight the complexity of peripheral sTREM2 and support the necessity of longitudinal studies including both CSF and plasma samples to elucidate its diagnostic value.