Establishment of MHHi001-A-5, a GCaMP6f and RedStar dual reporter human iPSC line for in vitro and in vivo characterization and in situ tracing of iPSC derivatives.

Transgenic hiPSC lines carrying reporter genes represent valuable tools for functional characterization of iPSC derivatives, disease modelling and clinical evaluation of cell therapies. Here, the hiPSC line 'Phoenix' (Haase et al., 2017) was genetically engineered using TALEN-based integration of the calcium sensor GCaMP6f and RedStarnuc reporter into the AAVS1 site. Characterization of undifferentiated cells and functional investigation of hiPSC-derived cardiomyocytes-containing BCTs showed a strong intracellular calcium transient-dependent GCaMP6f and eminent RedStarnuc signal. Therefore, our dual reporter line provides an excellent tool to facilitate monitoring of engraftment, calcium fluctuations and coupling of iPSC derivatives such as cardiomyocytes in vitro and in vivo in animal models.