Fig. 6
Optical action potentials in WT versus GCaMP3+ hESC-CMs in vitro. a Fluorescence traces derived from representative WT (upper) or GCaMP3+ (lower) ESI-17 hESC-CM aggregates simultaneously imaged on the di-2-ANEPEQ (“red,” voltage) and GCaMP3 (“green,” intracellular calcium) channels during pacing at 1 Hz. b Mean oAPD90 values for WT versus GCaMP3+ hESC-CM aggregates generated from each of the three parental lines. c, d Corresponding fluorescence traces from representative individual WT (upper) or GCaMP3+ (lower) ESI-17 hESC-CMs, as well as mean oAPD90 values for WT versus GCaMP3+ hESC-CMs from each of the three parental lines when recorded as single cells. Note that, using both preparations, GCaMP3+ cardiomyocytes from the ESI-17 and RUES2 hESC lines showed significantly longer oAPDs than their WT counterparts. Results are from n > 12 recordings per condition using cells from at least three differentiation runs. *p < 0.05, **p < 0.01, ***p < 0.001