Adipose-Derived Stem Cell Therapy in Spinal Cord Injury

Abstract

Spinal cord injury (SCI) is a serious condition accompanied by severe adverse events that affect several aspects of the patient's life, such as motor, sensory, and functional impairment. Despite its severe consequences, definitive treatment for these injuries is still missing. Therefore, researchers have focused on developing treatment strategies aimed at ensuring full recovery post-SCI. Accordingly, attention has been drawn toward cellular therapy using mesenchymal stem cells. Considering their wide availability, decreased immunogenicity, wide expansion capacity, and impressive effectiveness in many therapeutic approaches, adipose-derived stem cell (ADSC) injections in SCI cases have been investigated and showed promising results. In this review, SCI pathophysiology and ADSC transplantation benefits are discussed independently, together with SCI animal models and adipose stem cell preparation and application techniques. The mechanisms of healing in an SCI post-ADSC injection, the outcomes of this therapeutic approach, and current clinical trials are also deliberated, in addition to the challenges and future perspectives, aiming to encourage further research in this field.

Keywords: adipose tissue; spinal cord injury; stem cells; transplantation.

Figure 1

Spinal cord injury phases’ pathophysiology: (A) acute phase pathophysiology marked by ischemia, hemorrhage, red and white blood cell recruitment, and inflammatory cytokine secretion by neutrophils; (B) sub-acute phase marked by Wallerian degeneration and retraction bulbs formation, axonal demyelination, and the beginning of astrogliosis; (C) chronic phase marked by glial scar and cyst formation. TNF-α: tissue necrosis factor alpha, IL-1: interleukin-1, IL-6: interleukin-6.

Figure 2

Injury patterns in SCI animal models (A) SCI induction by contusion (B) SCI induction by compression (C) SCI induction by distraction (D) SCI induction by dislocation (E) SCI induction by transection (F) SCI induction with chemical.

Figure 3

ADSC collection and transplantation in SCI: (A) fat harvesting; (B) ADSC isolation; (C) ADSC culture and expansion; (D) ADSC differentiation; (E) ADSC transplantations. PBS: phosphate-buffered saline, P/S: penicillin/streptomycin, CO₂: carbon dioxide, rpm: round per minute, SVF: stromal vascular fraction, DMSO: dimethyl sulfoxide, BHA: butylated hydroxyanisole, bFGF: basic fibroblast growth factor, EGF: epidermal growth factor.