Long-Term Cultures of Spinal Cord Interneurons

Frontiers in Cellular Neuroscience, 2022 · DOI: 10.3389/fncel.2022.827628 · Published: February 7, 2022

Simple Explanation

This study introduces a new in vitro model using mouse primary spinal cord neuronal cultures to investigate the properties of spinal cord interneurons (SpINs). These neurons are matured over 15 days, showing expression of maturity markers and formation of synapses. The model allows for the analysis of maturation, morphology, physiology, connectivity, and regeneration of identified interneurons. It involves isolating neurons from E14 mice and observing their development and responses to stimuli. Live neurons at different maturation stages were cut using a laser to observe axon regeneration. The study found that the regenerative ability of axons decreases as the neurons mature, indicating a potential limitation of older neurons.

Study Duration

72 days

Participants

E13.5-E14.5 embryos of the C57BL/6J mice

Evidence Level

Not specified

Key Findings

1
Spinal cord interneurons (SpINs) can be cultured long-term (over 2 months) in a defined, simple serum-free medium.
2
The neurons in culture form synapses, acquire mature electrical properties, express markers of SpINs, and lose regenerative capacity, modeling the maturing and mature CNS.
3
Regenerative capacity of axons decreases with neuronal maturity, with a significant reduction observed between DIV7 and DIV16, and complete loss by DIV23.

Research Summary

This study optimized a method for culturing primary spinal cord neurons, enabling stable cultivation, maturation, and characterization of interneurons isolated from E14 mouse embryos. The cultures were analyzed for cellular composition, neuronal maturity (via immunocytochemistry and patch-clamp), and regenerative capacity (via laser axotomy). The study demonstrates that the developed culture model efficiently mimics the biology of the spinal cord, providing a valuable tool for future regenerative and developmental studies.

Practical Implications

Drug discovery platform

The new culture method can serve as a platform for testing new regeneration treatments for spinal cord injury.

Developmental studies

The culture model facilitates developmental and functional studies of spinal cord interneurons.

Understanding regeneration limits

The model allows for further comprehension of the limits of CNS regeneration and subsequently to discovery of new therapeutic avenues.

Study Limitations

1
Proliferation of glia during long-term culture, though not affecting neuron survival, can complicate analysis.
2
Lack of specific markers makes it difficult to definitively identify all neuronal subtypes present in the culture.
3
Absence of motor neurons after long-term cultivation limits the model's applicability for studying motor neuron-related processes.

Your Feedback

Was this summary helpful?

Back to Spinal Cord Injury