A Microfluidic Cell Culture Platform for Modeling Aligned Peripheral Nerve Bundle, Connection, and Myelination

Area of Science:

• Biomedical Engineering
• Neuroscience
• Regenerative Medicine

Background:

• Traditional polydimethylsiloxane (PDMS) microfluidic platforms for peripheral nervous system research face limitations in scalability and physiological relevance.
• There is a need for advanced organ-on-a-chip systems that allow for precise control over neuronal organization and myelination.
• Current models often fail to recapitulate the complex in vivo microenvironment of nerve bundles.

Purpose of the Study:

• To develop and validate a novel 3D-printed organ-on-a-chip platform for studying sensory neurite alignment and myelination.
• To create a standardized, high-throughput system that overcomes the limitations of traditional PDMS platforms.
• To investigate the effects of neurite alignment on neuronal growth and Schwann cell-mediated myelination.

Main Methods:

• Utilized 3D printing to fabricate a microfluidic chip integrating open and closed systems for stable fluid dynamics.
• Developed a co-culture system of primary sensory neurons (SN) and Schwann cells (SCs) to mimic in vivo nerve bundle organization.
• Employed finite element modeling and fluid dynamics simulations to optimize chip design for nutrient distribution and biomechanical forces.
• Quantified neurite growth and myelination using microscopy and analyzed g-ratios and nodes of Ranvier.

Main Results:

• Neurite alignment significantly enhanced neuronal growth, with aligned neurites showing up to a 2-fold increase in area and length compared to random controls.
• The structured environment facilitated efficient Schwann cell-mediated myelination, forming compact myelin sheaths with physiologically relevant g-ratios (∼0.6) and nodes of Ranvier.
• The platform successfully recapitulated both myelinated and non-myelinated Remak bundles, mirroring native sensory nerve structures.

Conclusions:

• The 3D-printed organ-on-a-chip platform provides a cost-effective, resource-efficient, and high-throughput solution for studying peripheral nerve biology.
• This versatile tool enables precise investigation of neurite alignment, myelination, and nerve bundle formation.
• The platform holds significant potential for advancing research in pain, neurological disease modeling, and regenerative medicine applications.