Three-Dimensional-Cultured MSC-Derived Exosome-Hydrogel Hybrid Microneedle Array Patch for Spinal Cord Repair

Exosomes derived from mesenchymal stem cells (MSCs) have
been proven
to exhibit great potentials in spinal cord injury (SCI) therapy. However,
conventional two-dimensional (2D) culture will inevitably lead to
the loss of stemness of MSCs, which substantially limits the therapeutic
potency of MSCs exosomes (2D-Exo). Exosomes derived from three-dimensional
culture (3D-Exo) possess higher therapeutic efficiency which have
wide applications in spinal cord therapy. Typically, conventional
exosome therapy that relies on local repeated injection results in
secondary injury and low efficiency. It is urgent to develop a more
reliable, convenient, and effective exosome delivery method to achieve
constant in situ exosomes release. Herein, we proposed
a controlled 3D-exohydrogel hybrid microneedle array patch to achieve
SCI repair in situ. Our studies suggested that MSCs
with 3D-culturing could maintain their stemness, and consequently,
3D-Exo effectively reduced SCI-induced inflammation and glial scarring.
Thus, it is a promising therapeutic strategy for the treatment of
SCI.