TREM2 and tauopathy: However, when Bemiller et al. [293] crossed the TREM2 knockout mouse with a less aggressive mouse model of tauopathy, the authors observed a decrease in microgliosis in TREM2-deficient mice, as observed in TREM2-deficient PS19 mice, but reported that the complete deletion of TREM2-exacerbated tau pathology.