Generation of functional cardiomyocytes from rat embryonic and induced pluripotent stem cells using feeder-free expansion and differentiation in suspension culture
Fig 4
Detection of sarcomeric structures and gap junctions in rPSC-derived cardiomyocytes.
(A) Immunofluorescence stainings of cryosections (thickness: 10 μm) of 14 days old beating EBs derived from rESCs and riPSCs differentiated in scalable suspension culture. Sarcomeric α-Actinin and gap junction protein Cx43. Nuclei are counterstained with DAPI. Scale bars: 100 μm. (B) Immunofluorescence staining of sarcomeric α-Actinin and Cx43 on cells after dissociation of EBs (day 14) and re-seeding on fibronectin coated glass-bottom dishes. Scale bars: 100 μm. (C) Transmission electron microscopy images of ultra-thin sections (approx. 70 nm) of EBs on day 14 of differentiation showing distinct Z-bands (z) of myofibrils, abundant mitochondria (m), and dark granules of glycogen (gly) depositions. Arrowheads indicate cisternae of sarcoplasmic reticulum in close proximity to Z-bands. Scale bars: 500 nm.