First Evidence of Functional Neuronal Remodeling In Vitro in a Cell Line from an Evolutionarily Ancient Vertebrate (Sturgeon).

The targeted differentiation of stem cell-like cells into functional neurons is a central goal in developmental biology and comparative neurobiology. In this study, we report for the first time on the successful neuronal remodeling of cell line derived from the Atlantic sturgeon larvae (Acipenser oxyrinchus; AOXlar7y) under defined in vitro conditions. The cells were cultured on poly-D-lysine-coated surfaces and exposed to a reduced-serum medium supplemented with nerve growth factor-β to induce neuronal differentiation. Morphologically, time-dependent formation of neurite-like processes and network structures was observed over a period of 14 days. The neuronal identity of the differentiated cells was confirmed by immunocytochemistry with the neuronal marker NeuN. Functional maturation was examined by measurement of cytoplasmatic calcium activity. After stimulation with 200 µM ATP, cells with neuronal morphology showed distinct intracellular calcium transients, indicating functional purinergic signaling pathways. AOXlar7y thus represents a novel in vitro model for studying neurogenesis and neuronal function in a cellular model of ancient fish species and provides a valuable basis for future studies in comparative neurobiology, neurotoxicology, and evolutionary developmental biology.