A representative image series from combined FISH for human and rat specific chromosomes and immunofluorescence for human albumin in the multiple AA-treated rat liver-transplanted hMSCs. (A) When viewed through a rhodamine and ultraviolet filter, positive human Y signals appear as red dots at the periphery of the nuclei stained with DAPI, a chromosomal marker that shows up as blue fluorescence. For ease of reference, the positive Y signals are highlighted by arrows. (B) The same field as in panel A is shown when overlaying the immunofluorescence images viewed through the FITC filter to demonstrate the immunostaining for the human albumin positive cytoplasm (green staining), and the rat-12 chromosome is represented by the green fluorescent dots (arrowheads). Nonhuman albumin-expressing cells which show background level of autofluorescence in injured rat liver tissue are seen surrounding the albumin-expressing cells. (C) Another representative image from different rat livers was made from overlaying the images seen through the 3 separate filters to show all the colors. Scale bars represent 20 μm. Original magnification, × 630.