GJA1 and infarction: Human skeletal myogenic cells overexpressing Cx43 (huSkMCx43 + MSC) or not (huSkM + MSC) supported by mesenchymal stem cells were able to proliferate at the site of administration in the post-infarction heart (Figure 7b–d), while in the healthy heart, no change in signal intensity for huSkMCx43+ MSC was observed (Figure 6c,d).