eLife assessment
This work provides valuable new insights into the mechanisms by which 25-hydroxycholesterol (which is known to be rapidly produced in macrophages and other cells during acute infections) acts to protect cells and animals from microbial infection. The authors provide compelling evidence that the cholesterol-esterifying enzyme acylCoA:cholesterol acyltransferase (ACAT) that is induced by 25-hydroxycholesterol promotes the depletion of an accessible pool of plasma membrane cholesterol, producing anti-microbial effects.