Fig. 7. Sca-1 transcripts are required for CSC proliferation and survival in vivo. (A) Immunohistochemistry of transplanted lacZ⁺ cells 3 days after infarction. Transplanted lacZ⁺ cells entering cell cycle were detected as Ki67-positive cells (arrowheads) (n=6). Myocardial infarction transplanted with NTG-CSCs (C6) and Sca-1 KD CSCs (C1) are shown. ^*P<0.01 versus NTG. (B) Apoptotic features (arrowheads, brown nuclei) of lacZ⁺ engrafted cells are shown at day 3 after NTG- or Sca-1 KD-CSC transplantation. ^*P<0.01 versus NTG-CSC transplantation (n=6). Bars, 50 µm in A,B.