Architecture-Engineered Electrospinning Cascade Regulates Spinal Microenvironment to Promote Nerve Regeneration

Area of Science:

• Biomaterials Science
• Neuroscience
• Immunology

Background:

• Spinal cord injury (SCI) triggers inflammation, leading to stem cell death and hindering nerve regeneration.
• Coordinating immune responses with neural stem cell (NSC) function is crucial for central nervous system (CNS) recovery.

Purpose of the Study:

• To engineer a composite biomaterial for nerve injury repair.
• To investigate the composite's ability to modulate the inflammatory microenvironment and promote NSC-mediated regeneration.

Main Methods:

• Integration of a hydrogel "perfusion" system and electrospinning technology to create a composite support.
• Assessment of macrophage polarization (M2 subtype) and NSC recruitment/differentiation.
• Evaluation of nerve function recovery in a rat SCI model.

Main Results:

• The composite hydrogel induced M2 macrophage polarization, reprogramming the SCI immune microenvironment.
• Released factors (SDF-1α, BDNF) significantly increased NSC recruitment (4x) and neuronal differentiation (2x).
• The fiber system promoted blood vessel formation and improved nerve function in SCI rats.

Conclusions:

• The engineered fiber composite effectively modulates the inflammatory response post-SCI.
• It promotes nerve regeneration via a cytokine-delivery system, enhancing the biomaterial's inherent immune-regulatory properties.
• This novel composite offers a promising therapeutic strategy for SCI treatment.