Figure 3.

Nestin⁺ striated cells express cardiac markers. (A–P): nestin⁺ striated (green in [A, C, E, G, I, K, N, O] and red in [J, L], indicated by white arrows) but not interstitial (# in [A–C, E–G, M–O]) cells expressed cTnI (red [B, C]), Cxn43 (red [F, G], gap junctions indicated by white arrowheads), Nkx2.5 (red [I–K]), and desmin (green [N, O]; greater intensity in nestin⁺ cells). (D, H, L, P): Myocardium incubated with secondary antibody only as a control for background, nonspecific immunofluorescence. (F, G): Cxn43 was observed in the cytosol in some nestin⁺ striated cells (*). (O): Enlargement of region shown in (M) and (N), indicated by the white box in (M). (Q–S): Intense desmin expression (green [R, S]), in small-caliber nestin⁺ myofibers (red [Q, S]) in mdx/utrn^−/− skeletal muscle. (T): Skeletal muscle incubated with secondary antibody only as a control for background, nonspecific immunofluorescence. White asterisks in (M–O) represent myofibers not undergoing regeneration. Blue, DAPI-labeled nuclei. Abbreviations: cTpnI, cardiac troponin I; Cxn43, Connexin 43; DAPI, 4′,6-diamidino-2-phenylindole.