Fig. 6

Transgenic expression of hCD33M in mouse microglial dampens phagocytosis. a Flow cytometry-based competitive phagocytosis gating strategy for WT (GFP⁻hCD33⁻) and hCD33M-Tg (GFP⁺hCD33M⁺) microglia. The competitive phagocytotic assay was carried out with hCD33M-Tg microglia on a mCD33^+/+ background (b–e) or mCD33^−/− background (f–i) where the non-transgenic (hCD33M⁻) microglia are WT or mCD33^−/−, respectively. Flow cytometry-based uptake of b, f dextran particles (14 independent experiments for mCD33^+/+ and 4 independent experiments for mCD33^−/−), c, g polystyrene beads (11 independent experiments and 6 independent experiments for mCD33^−/−), d, h myelin (5 independent experiments and 5 independent experiments for mCD33^−/−), and e, i aggregated Aβ_1-42 (5 independent experiments and 5 independent experiments for mCD33^−/−). For cells on a mCD33^+/+ background (b–e), a representative flow cytometry histogram is shown for each cargo and summary plots for each assay, where the average value for the hCD33 non-expressing cells was set to 100%. Statistical significance based on a paired Student’s T-test.