FIG. 5.

Detection of Runx2 and Twist2 in MSC by immunocytochemical staining. Expression and distribution of Runx2 and Twist2 proteins were investigated by immunocytochemistry/immunocytochemical in bmMSC (a–l) and pMSC (m–x) with antibodies as indicated. Nuclei were visualized by 4′,6-diamidino-2-phenylindol-dihydro-chlorid counterstaining and different areas of representative samples of MSC from three donors are shown. Expression of Runx2 (red, Cy3) is localized in and around the nuclei (d, l, p, x), whereas Twist2 [green, fluorescein isothiocyanate (FITC)] is spread all over the cytoplasm (h, t). In a few bmMSC, nuclear Twist2 was detected (h, arrows). There is no homogenous appearance of the distribution of Runx2- and/or Twist2-expressing cells across the samples. There are regions where only Runx2 (a, m) or Twist2 (f, r) is detected. In some areas, expression of both proteins is observed (k, w). Color images available online at www.liebertpub.com/scd