Side population (SP) cells from Tg(CD41:GFP) zebrafish overlaps with CD41-GFP^lo subpopulation. The top panel flow cytometric diagrams show typical SP profile derived from lymphocyte and progenitor subsets of CD41-GFP WKM cells after incubation with the Hoechst 33342 dye in presence (on the right) or absence of verapamil (on the left). Vertical axis shows blue Hoechst fluorescence; horizontal axis shows red Hoechst fluorescence. The SP cells are indicated within the gate. The lower 2 panels indicate the percentage of SP cells that are also CD41-GFP^lo. Here the vertical axis shows FITC fluorescence; horizontal axis shows forward scatter. Two gates mark CD41-GFP^lo and CD41-GFP^hi subsets, respectively. The SP cells overlap with CD41-GFP^lo by > 20%.