Unperturbed dye-based imaging of spontaneous synchronized calcium activity in iPSC-derived neuronal cultures
Summary
Synchronous calcium (Ca2+) bursting is a hallmark of neuronal network maturation. While microelectrode array (MEA) recordings are routinely used to generate population-averaged measurements on this functional network activity, live cell Ca2+-imaging offers single-cell resolved, contextual data. Unfortunately, most electrophysiologically active cells are hypersensitive to medium exchange, which is standard practice in most sensor dye-based Ca2+-imaging protocols. Here, we found that the use of conditioned imaging medium preserves spontaneous network activity of iPSC-derived glutamatergic and motor neuron cultures. The effect was consistent across different cell lines and seeding densities and allowed for the faithful detection of disease-specific phenotypes, as shown using a KCNQ2-related epilepsy model. Our findings thus provide a simple, robust strategy to measure spontaneous network activity in Ca2+-imaging experiments, broadening the utility of this technique for functional phenotyping, disease modeling, and drug screening with cellular resolution. © 2026 The Authors.
| Authors | Dirkx N, Asselbergh B, Verstraelen P, Van Lent J, De Vriendt E, Timmerman V, De Vos WH, Weckhuysen S |
|---|---|
| Journal | iScience |
| Publication Date | 2026 May 15;29(5):115689 |
| PubMed | 42080132 |
| PubMed Central | PMC13133964 |
| DOI | 10.1016/j.isci.2026.115689 |