TREM2 and dementia: We found no difference in the mRNA and protein surface expression level of the dementia-causing or associated genes CSF1R and CD33. It was recently reported that CD33 modulates TREM2 surface expression in human peripheral blood mononuclear cells (Chan et al., 2015) and that TREM2 KO macrophages have increased apoptosis in response to the withdrawal of CSF-1 (Wu et al., 2015).