Figure 5.

Nestin⁺ transitional cells express early, but not late, markers of muscle cells and do not express stem cell markers. (A–O): Nestin⁺ elongated cells with striations (green in [A–D, F, G, I], red in [J, L, M, O], indicated by white arrowheads) were frequently observed in close proximity to CD68⁺ macrophages (red, indicated by white asterisks in [A]). They did not express cTpnI (red [E, F]) (a marker of mature cardiomyocytes), Sca-1 (red [H, I]), or Flk-1 (green [K, L]) stem cell markers on nestin⁺ interstitial cells, but they did express desmin (green [K, L]), an early marker of striated muscle. White arrows indicate nestin⁺ interstitial cells (A, G–I, J–L). White asterisks indicate nestin⁺ interstitial cells expressing Sca-1 (G–I), Flk-1 (J–L), or desmin (M–O). Blue, DAPI-labeled nuclei. Abbreviations: cTpnI, cardiac troponin I; DAPI, 4′,6-diamidino-2-phenylindole.