Basic NeuroscienceFluorescent probes as a tool for cell population tracking in spontaneously active neural networks derived from human pluripotent stem cells

- Fluorescent labels CT and DiD can be utilized with human stem cell-derived neurons.
- Labels do not affect the cell viability and minimally affect the cell proliferation.
- Labeled cells can be successfully followed for at least 4 weeks.
- Labeled cell populations form spontaneously active neural networks.

Applications such as 3D cultures and tissue modelling require cell tracking with non-invasive methods. In this work, the suitability of two fluorescent probes, CellTracker, CT, and long chain carbocyanine dye, DiD, was investigated for long-term culturing of labeled human pluripotent stem cell-derived neural cells. We found that these dyes did not affect the cell viability. However, proliferation was decreased in DiD labeled cell population. With both dyes the labeling was stable up to 4 weeks. CT and DiD labeled cells could be co-cultured and, importantly, these mixed populations had their normal ability to form spontaneous electrical network activity. In conclusion, human neural cells can be successfully labeled with these two fluorescent probes without significantly affecting the cell characteristics. These labeled cells could be utilized further in e.g. building controlled neuronal networks for neurotoxicity screening platforms, combining cells with biomaterials for 3D studies, and graft development.