Fig. 6. BacNa_v expression improves conduction and prevents reentrant activity in fibrotic cardiomyocyte cultures.

a, b Representative immunostaining images of monolayers containing fibroblasts and NRVMs labelled by vimentin and F-actin, respectively, exhibiting robust cardiac-specific GFP expression in the MHCK7-h2SheP-2A-GFP-transduced group (b) but not in the nontransduced control (a). c Representative isochrone activation maps of AP propagation in nontransduced NRVM monolayers (“No virus”) and monolayers transduced with MHCK7-GFP (“GFP”) or MHCK7-h2SheP-2A-GFP (“h2SheP”) lentivirus. d–f Monolayers transduced with h2SheP lentivirus (n = 18) exhibit improved CV (d), longer APD₈₀ (e), and similar MCR (f) compared to nontransduced (n = 26) or GFP-transduced (n = 31) monolayers. ****P < 0.0001 in d, e. g Representative isochrone activation map showing reentrant arrhythmia induced by rapid point pacing in a nontransduced monolayer (see also Supplementary Movie 3). In c, g pulse signs indicate location of pacing electrode and circles denote 504 recording sites. h Transduction with h2SheP lentivirus significantly reduced the rate of reentry incidence (fraction of monolayers with induced reentry) compared to nontransduced and GFP-transduced control groups. Error bars indicate s.e.m; statistical significance was determined by one-way ANOVA, followed by Tukey’s post-hoc test to calculate P-values. Source data are provided as a Source Data file.