Characterization of GFP+
cell populations in testis and skin in Oct4-Gfp (OG2) reporter mice. (A) Flow cytometry of cell suspensions from 1 wk old neonatal testis with compensation for autofluorescence by plotting FL1 against FL2. Dead cells are stained with propidium iodide (PI). (B) Timecourse analysis by flow cytometry of GFP + cells in testis at 0–2 wks, 3–4 wks, 6 wks and 24 wks of age. P vs 0–2 wks. (C) Representative FACS analysis and GFP+ gating of cell suspensions from skin. (D) Fluorescence microscopy of sorted GFP+ and GFP- cells for GFP, anti-OCT4 antibody staining (red) and nuclear dye (DAPI, blue). (E) GFP+ skin cells by FACS in different age groups (left), n = 36-45. Cyclic expansion of the GFP+ cell pool over time (right). n = 9-30. P vs 0.5 wks. (F) Immunostaining of hair follicle bulge region against smooth muscle α–actin (SMA) and GFP. Insert from same image in higher magnification. (G) Flow cytometry of GFP+ or GFP- gated cells from skin. CD34+ ITGα6hi and CD34+ ITGα6lo populations are indicated. (H) Representative flow cytometry profile of GFP+ gated cells stained with specific antibodies (spec. ab) or isotype control (isotype). (I) mRNA expression (2ΔCt) by quantitative real-time PCR of pluripotency factors from sorted skin cells or cultures of iPS and ES cells. n = 3-4. Scale bar: 20 um. Magnification: (D) 640, (F) 200, 640 (insert).