Journal: Nature
Article Title: hESC-Derived Cardiomyocytes Electrically Couple and Suppress Arrhythmias in Injured Hearts
doi: 10.1038/nature11317
Figure Lengend Snippet: a, GCaMP3+ hESC-CM graft in a cryoinjured heart immunostained for GFP (green) and βMHC (red). Small graft nests were located in host muscle within the border zone, but most of the graft was in scar. b, Percentage of visible GCaMP3+ hESC-CM graft in each cryoinjured heart that showed 1:1 host-graft coupling at 14- and 28-days post-transplantation (n=7 and n=15 animals, respectively). c, Representative 28-day-old GCaMP3+ hESC-CM graft in a cryoinjured heart imaged ex vivo during mechanical arrest with blebbistatin and pacing at 3 Hz. Upper: Traces of mean fluorescent intensity versus time for graft regions located within host muscle (‘1’, blue) and the cryoinjury zone (‘2’, red). Both were activated in a 1:1 correlation with the host ECG (black). Lower: Corresponding activation map showing the interval (in ms) between the stimulus pulse and the local rise in GCaMP3 fluorescence. Graft in host muscle (1) showed uniformly rapid activation, while graft in scar (2) activated first in central scar and then gradually progressed toward the border zone. In other instances, graft activation started at the border zone and radiated into the scar. d , GCaMP3 fluorescence and EGG traces (upper) as well as the activation map (lower) for a representative GCaMP3+ hESC-CM graft in a blebbistatin-arrested uninjured heart. This graft showed 1:1 host-graft coupling and a brief interval between stimulus and GCaMP3 transient upstroke.
Article Snippet: In brief, each animal was mechanically ventilated, anesthetized with 2% isoflurane, and outfitted for standard surface ECG recordings (ADInstruments).
Techniques: Transplantation Assay, Ex Vivo, Activation Assay, Fluorescence
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