CAA pathology was identified in 59.18% of community donors, with CAA type 1 closely associated with AD pathology and cognitive decline, and transcriptome analysis revealing TREM1 as a potential gene associated with more severe pathological progression of CAA type 1.
CAA pathology was identified in more than half of community autopsy donors.
Both CAA type and stage were significantly correlated with Alzheimer's disease neuropathologic change (ADNC).
CAA type 1 was closely associated with AD pathology and cognitive decline.
Transcriptome analysis of occipital lobe specimens identified differentially expressed genes with GO enrichment concentrated in immune response-activating and -regulating signaling pathways.
TREM1 (Triggering receptor expressed on myeloid cells 1) was identified as a gene involved in immune signal amplification and more strongly expressed in the CAA type 1 subtype.
This research suggests that cerebral amyloid angiopathy (CAA) — a condition where a protein called amyloid-beta builds up in the walls of blood vessels in the brain — is very common in the general population, found in nearly 60% of brain tissue donors examined at autopsy. The study analyzed 49 brain samples from a Chinese brain bank and found that the severity and subtype of CAA were both linked to the brain changes associated with Alzheimer's disease. In particular, one subtype called CAA type 1 was most strongly connected to Alzheimer's-related brain pathology and cognitive decline, suggesting CAA is not just an isolated vascular problem but actively contributes to Alzheimer's disease progression. Using gene expression analysis (transcriptomics) on 21 brain tissue samples, the researchers found that the genes most altered in CAA were concentrated in immune system signaling pathways. One gene in particular, TREM1, which plays a role in amplifying immune responses in the brain, was more active in CAA type 1 cases. This points to immune system dysregulation as a potentially important mechanism in how CAA worsens over time. This research suggests that CAA should be viewed as a significant contributor to Alzheimer's disease rather than an independent condition, and that the immune-related gene TREM1 may be a useful target for future research into why some people with CAA develop more severe brain disease. These findings are based on postmortem brain tissue, so further studies in living patients would be needed to confirm these associations and explore their clinical implications.
Zhang Y, Ye M, Mi S, Zhou Y, Yu Q, Liang J, et al.. (2026). An analysis of cerebral amyloid angiopathy based on samples from human brain bank.. Frontiers in immunology. https://doi.org/10.3389/fimmu.2026.1933760