As previously discussed, Wang et al. found that TREM2 does not directly mediate phagocytosis, instead TREM2’s function in the CNS is two-fold—TREM2 is a sensor that detects lipids that are exposed during conditions of brain injury/insult and TREM2 promotes microglial survival via CSF-1R signaling [62]. Here, TREM2 is linked to brain injury.