Figure 4: Engraftment of human ATSCs within newborn rat brain. (a) Confocal microscopy micrographs showing the engraftment of eGFP-positive (green; A, D) ATSCs within newborn rat brain 1 week after cell infusion. ATSCs exhibit a round morphology (A, C), are surrounded by GFAP-positive astrocytes (red; B, D), and express TRKA (red, B, D, arrows). (b) Engraftment and in vivo differentiation of human ATSCs within newborn rat hippocampus 2 weeks after implantation. Confocal images of GFAP (red; A) or TRKA (red; D) immunolabeled eGFP (green; B, E) expressing ATSCs. Engrafted cells express the astrocytic marker GFAP (yellow, C) and the TRKA receptor (yellow, F). Scale bars: (a) A–C 120 μm, (a) D–F 420 μm, (b) A–C 80 μm, and (b) D–F 60 μm.