Loss of TREM2 facilitates tau accumulation, spreading, and brain atrophy, but only in the presence of amyloid pathology.
Neuron. 2021 Apr 21;109(8):1243-1245. doi: 10.1016/j.neuron.2021.03.029. PMID: 33887187.
TREM2 variants increase the risk for Alzheimer’s disease. In this issue of Neuron, Lee et al. demonstrate that TREM2-dependent microglial functions prevent accumulation and spreading of tau, but only in the presence of amyloid pathology. This provides additional fuel for the amyloid cascade hypothesis and supports a protective function of microglia.