Figure 4. Functional analysis of hiPSC-derived cardiomyocyte spheroids.
(A) Average contraction amplitude from Day 1 to Day 7 of each group. Double asterisk (**) represents statistical difference between all groups. (B, C) Representative fractional area change (i.e., contraction amplitude) of spontaneously beating spheroids with and without e-SiNWs at time points Day 0 and Day 6; n = 6 spheroids per condition. (D, E) Representative calcium transient imaging of 7 regions of interest (colored circles) per spheroid for each group. Fluorescence amplitude, F/F0, refers to measured fluorescence intensity normalized to background fluorescence intensity. (F) Comparison of the peak value of F/F0 for each group. (n=3) (G) Comparison of calcium release duration for each group. (n=3) hiPSC-NC= human induced pluripotent stem cell cardiac spheroids, no e-SiNWs, no stimulation; hiPSC-WC= human induced pluripotent stem cell cardiac spheroids, with e-SiNWs, no stimulation. Asterisks (*) represent statistical significance with p<0.05; error bar represents standard deviation. Scale bars = 100 μm.