Over a Century of Neuron Culture: From the Hanging Drop to Microfluidic Devices

The brain is the most intricate, energetically active, and plastic organ in thebody. These features extend to its cellular elements, the neurons and glia.Understanding neurons, or nerve cells, at the cellular and molecular levels isthe cornerstone of modern neuroscience. The complexities of neuron structure andfunction require unusual methods of culture to determine how aberrations in orbetween cells give rise to brain dysfunction and disease. Here we review themethods that have emerged over the past century for culturing neurons invitro, from the landmark finding by Harrison (1910) — that neuronscan be cultured outside the body — to studies utilizing culture vessels,micro-islands, Campenot and brain slice chambers, and microfluidic technologies.We conclude with future prospects for neuronal culture and considerations foradvancement. We anticipate that continued innovation in culture methods willenhance design capabilities for temporal control of media and reagents(chemotemporal control) within sub-cellular environments of three-dimensionalfluidic spaces (microfluidic devices) and materials (e.g., hydrogels). They willenable new insights into the complexities of neuronal development andpathology.