LGR5 and Hepatic fibrosis: Using FACS, we isolated Lgr5-GFP+ liver stem cells from Lgr5-GFP mice treated with 1XCCL4, and injected these cells intrasplenically into the wild-type C57 mice with acute liver damage (single CCL4 treatment) or chronic liver damage (liver fibrosis model, 2XCCL4 treatment/week for 6 weeks, Fig. 1a).