TABLE 5.

Mechanisms of action of stem cells in SCI.

Mechanisms of action of stem cells in spinal cord injury	Description
Cell replacement	Stem cells differentiate into various cell types in the injured spinal cord, such as neurons, oligodendrocytes, and astrocytes, to replace lost or damaged cells and restore neural function.
Trophic support	Stem cells secrete various trophic factors, such as growth factors, cytokines, and extracellular vesicles, to promote cell survival, proliferation, differentiation, and axonal regeneration, and to reduce inflammation and apoptosis.
Immunomodulation	Stem cells modulate the immune response in the injured spinal cord by secreting anti-inflammatory factors, interacting with immune cells, and suppressing immune activation, to reduce tissue damage and promote tissue repair.
Angiogenesis	Stem cells induce angiogenesis in the injured spinal cord by secreting angiogenic factors and promoting the proliferation and differentiation of endothelial cells, to improve blood supply and tissue perfusion, and to enhance tissue repair and regeneration.

SCI, spinal cord injury.