CH25H and ischemic stroke: Moreover, we conducted flow cytometry (Additional file 2: Fig. S5B) and immunofluorescence experiments (Fig. 4I) in vitro, in which we treated microglial cell line BV2 cells with 25-hydroxycholesterol (25-HC), a metabolite of CH25H, and found increased phagocytic ability (Fig. 4H, I. These findings suggest that Ch25h, which is specifically expressed in CH25H+ MG6, plays a critical role in the phagocytic ability of microglia after ischemic stroke and accounts for the neuroprotective and anti-inflammatory properties of microglia after stroke.