Microenvironment-responsive immunoregulatory electrospun fibers for promoting nerve function recovery

Nat Commun. 2020 Sep 9;11(1):4504. doi: 10.1038/s41467-020-18265-3.

Abstract

The strategies concerning modification of the complex immune pathological inflammatory environment during acute spinal cord injury remain oversimplified and superficial. Inspired by the acidic microenvironment at acute injury sites, a functional pH-responsive immunoregulation-assisted neural regeneration strategy was constructed. With the capability of directly responding to the acidic microenvironment at focal areas followed by triggered release of the IL-4 plasmid-loaded liposomes within a few hours to suppress the release of inflammatory cytokines and promote neural differentiation of mesenchymal stem cells in vitro, the microenvironment-responsive immunoregulatory electrospun fibers were implanted into acute spinal cord injury rats. Together with sustained release of nerve growth factor (NGF) achieved by microsol core-shell structure, the immunological fiber scaffolds were revealed to bring significantly shifted immune cells subtype to down-regulate the acute inflammation response, reduce scar tissue formation, promote angiogenesis as well as neural differentiation at the injury site, and enhance functional recovery in vivo. Overall, this strategy provided a delivery system through microenvironment-responsive immunological regulation effect so as to break through the current dilemma from the contradiction between immune response and nerve regeneration, providing an alternative for the treatment of acute spinal cord injury.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Differentiation / drug effects
  • Cell Differentiation / immunology
  • Cellular Microenvironment / immunology*
  • Delayed-Action Preparations / administration & dosage
  • Disease Models, Animal
  • Drug Delivery Systems / instrumentation*
  • Drug Liberation
  • Female
  • Humans
  • Hydrogen-Ion Concentration
  • Interleukin-4 / administration & dosage
  • Liposomes
  • Mesenchymal Stem Cells / drug effects
  • Mesenchymal Stem Cells / physiology
  • Nerve Growth Factor / administration & dosage*
  • Nerve Growth Factor / pharmacokinetics
  • Nerve Regeneration / drug effects*
  • Nerve Regeneration / immunology
  • Rats
  • Recovery of Function / immunology
  • Spinal Cord / cytology
  • Spinal Cord / drug effects
  • Spinal Cord / immunology
  • Spinal Cord Injuries / immunology
  • Spinal Cord Injuries / therapy*
  • Tissue Scaffolds*

Substances

  • Delayed-Action Preparations
  • Liposomes
  • Interleukin-4
  • Nerve Growth Factor