FISH analysis of Y chromosome in the hepatic stellate cells. (A) Merged image of EGFP (green), Cy3-conjugated Y chromosome paint probe (yellow dots), and DAPI nuclear counterstain (blue) in the liver of mice that had received clonal cell transplants. White asterisks indicate EGFP⁺ cells with only one Y chromosome. Original magnification, ×400. Bar equals 30 μm. Images were obtained by a Leica DMRA2 equipped with a 40×/0.7 PL Fluotar objective lens, a DC350FX CCD camera, and CW4000FISH software. Images were processed using Adobe Photoshop 7.0. (B) Merged image of EGFP (green), vimentin (yellow), Cy3-conjugated Y chromosome paint probe (red dots), and DAPI (blue) in 3-day–cultured nonparenchymal cells, which were isolated from the livers of mice that had received clonal cell transplants and were treated with CCl₄. White triangles indicate EGFP⁺vimentin⁺ cells with only one Y chromosome. Original magnification, ×400. Bar equals 30 μm. Images were acquired and processed as in panel A.