Toll-like receptor 9 (TLR9), expressed in both microglia and neurons of the CNS, represents a promising therapeutic target for Alzheimer's disease (AD). While either microglial or neuronal TLR9 activation exerts neuroprotective effects that ameliorate AD pathology and preserve cognitive function, CpG oligodeoxynucleotides (ODNs), the synthetic agonists, cannot cross the blood-brain barrier (BBB). To overcome this, we developed tNCpG, an apolipoprotein E (ApoE)-functionalized polymersome nanocarr...