Table 1 Summary of confounding results from manipulations of miR155, TREM2, or INPP5D in various mouse models of Alzheimer’s pathology

PSAPP X miR155 pancellular constitutive knockout [3]

Increased

Unchanged

N/A

Improved

PSAPP X miR155 microglia-specific inducible knockout (PS1^Δexon9) [5]

Decreased

Increased

N/A

N/A

PSAPP X miR155 microglia-specific inducible knockout (PS1^L166P) [6]

Increased compaction

Decreased

Decreased

Improved

5xFAD X microglial TREM2 inducible overexpression (early induction) [10]

Decreased early and mid-stage; no change late stage

Decreased; increased microglia around plaque

Decreased

N/A

5xFAD X microglial TREM2 inducible overexpression (mid-stage induction) [10]

Decreased early and mid-stage; no change, late stage

Decreased; increased microglial & dynamics around plaques

Unchanged

N/A

5xFAD X microglial TREM2 ^R47H inducible overexpression (early induction) [10]

Increased mid-stage; no change late stage

Decreased; decreased microglia dynamics around plaques; no change microglia number per plaque

Increased

N/A

5xFAD X TREM2 ^H157Y CRISPR knock-in [11]

Decreased

Decreased

Decreased

Enhanced LTP

5xFAD X AAV sTREM2 or sTREM2 protein [13]

Decreased

Increased

N/A

Improved

WT X AAV TREM2 [14]

N/A

Increased phagocytosis

N/A

Impaired

PSAPP X AAV TREM2KO (early-middle) [14]

Unchanged

Inhibited phagocytosis

N/A

Improved

PSAPP X AAV TREM2 KO (middle-late) [14]

Increased

Inhibited phagocytosis

N/A

Impaired

PSAPP X AAV TREM2 (early-middle) [14]

Decreased

Increased phagocytosis

N/A

Impaired

PSAPP X AV TREM2 (middle-late) [14]

Decreased

Increased phagocytosis

N/A

Improved

5xFAD or APPPS121 TREM2 constitutive knockout [15]

Decreased

Decreased

Decreased

N/A

PS2APP X TREM2 −/− constitutive knockout (6–7 months, females) [16]

Increased

Decreased

Increased

N/A

PS2APP X TREM2 −/− constitutive knockout (12, 19–22 months, both sexes) [16]

Decreased

Decreased

Increased

N/A

PS2APP X TREM2 (−/−) vs (+/+) [16]

Intermediate Decrease

Intermediate effect on microglial clustering

Increased

N/A

APP knock-in + TREM2 activating antibody [17]

Decreased

Increased phagocytosis

N/A

N/A

APP knock-in + TREM2 blocking antibody 17

Decreased

Decreased

N/A

N/A

5xFAD + TREM2 activating antibody (chronic) [19]

Unchanged

Migration toward plaques

Increased

N/A

TREM2 KO pancellular knockdown (−/+) vs (−/−) [20]

N/A

(−/+) Increased; (−/−) protected

(−/+) Increased; (−/−) protected

N/A

PSAPP X INPP5D microglial knockout [21]

Increased

Increased

N/A

N/A

5xFAD X INPP5D microglial knockout [22]

Unchanged

Increased

Increased

N/A

APP ^{NL-G-F/NL-G-F} X INPP5D microglial knockout [23]

Unchanged

Unchanged

Unchanged

N/A

5xFAD X INPP5D pancellular knockout [24]

Decreased

Decreased

N/A

Improved