(a,b) Immunofluoresence micrographs of liver sections harvested from control (olive oil treated) or chronic CCl4 treated (x2 injections / week for six weeks) mTmG;Pdgfrb-Cre reporter mice or Ai14;Pdgfrb-Cre reporter mice (n = 4 male mice per group). Scale bars, 100 μm. (c,d) Immunofluoresence micrographs of liver sections from control (olive oil treated) (c) or CCl4 treated (d) Ai14;Pdgfrb-Cre mice (n = 4 male mice per group) stained for desmin, PDGFRβ or αSMA (green) with endogenous (not enhanced) Ai14-Td tomato report in red. (c) Scale bars, 25 μm. (d) Scale bar, 50 μm. Arrows indicate portal tracts in serial sections. (e) Gene expression profile of freshly sorted Td tomato positive cells from control (olive oil treated) or chronic CCl4 treated Ai14;Pdgfrb-Cre mice (n = 4 male mice per group). (f) Immunofluoresence staining of Td tomato positive cells sorted from the uninjured livers of Ai14;Pdgfrb-Cre mice and plated on tissue culture plastic for 7 days. Left panel shows Ai14 reporter (red), DAPI (blue), middle panel shows αSMA (green), DAPI (blue), right panel shows merged image. Scale bar, 100μm. Data are mean ± s.e.m. *P < 0.05, **P < 0.01, ***P < 0.001 (Student’s t test).