Figure 1.

Effect of phospholamban R14del mutation on cardiac muscle contractility in three-dimensional human engineered cardiac tissues. (A) Schematic of the methods. (B) Representative immunofluorescence images of mutant and corrected human engineered cardiac tissues stained for α-actinin (red), phospholamban (green) and DAPI (blue), scale bar = 25 µm. (C) Example twitch tracings from healthy (solid blue line), mutant (dashed red line), and corrected (solid black line) human engineered cardiac tissues during pacing at 1 Hz. (D) Twitch force parameters: developed force, +dF/dt, and −dF/dt (symbols indicate individual measurements, bars represent mean ± SD) analysed by ANOVA with Scheffe's post hoc test (corrected for multiple pairwise comparisons); n = 4 healthy, n = 7 mutant, n = 4 corrected human engineered cardiac tissues. (E) Spontaneous beat rate variability expressed as coefficient of variation, recorded from: n = 4 healthy, n = 4 mutant, and n = 3 corrected human engineered cardiac tissues (P = 0.209 by ANOVA). COV, coefficient of variation; hECTs, human engineered cardiac tissues.