Introduction

The spinal cord is an intricate web of channels that connects the brain to the body's other systems, transmitting messages and instructions. (Mark Patel, 2023) A spinal cord injury (SCI) is a catastrophic event that results in significant physical disability as well as compromised organ and system functions. It results in alterations to the motor, sensory, and autonomic functions of the cord that are occasionally temporary but typically permanent.³

Etiology of spinal cord injuries (SCI)

There are two primary classifications of (SCI): traumatic and non-traumatic SCI. The most frequent cause of SCI worldwide is trauma, which can result from falls, car crashes, or any impact trauma in the elderly. On the other hand, non-traumatic SCI may result from other causes such as spinal stroke or compression of the spinal cord by a mass lesion.²

Paraplegia & Quadriplegia

Damage to the spinal cord can cause both paraplegia and quadriplegia, two forms of paralysis. All four limbs and the torso are paralyzed in quadriplegia, also referred to as tetraplegia. The paralysis of the lower limbs and torso is known as paraplegia. Numerous ailments or injuries, such as trauma, inflammation, or spinal cord degeneration, can cause both quadriplegia and paraplegia. Depending on how severe it is, SCI can be classified as "complete" if all control over the region below the affected area is lost, or as "incomplete" if some sensation, muscle function, and other physiological functions are still present.³

Mesenchymal stem cell

Non-hematopoietic multipotent stem cells known as mesenchymal stem cells (MSCs). They have the capacity to differentiate into three different lineages: mesodermal (adipocytes, osteocytes, and chondrocytes), ectodermal (neurocytes), and endodermal (hepatocytes).⁴

Stem cell therapy

Since stem cells are often thought of as cells having the capacity to differentiate into other cells, they are extremely valuable in treating degenerative conditions. Stem cells are specifically used in SCIs to repair the damage primarily in SCI caused by trauma. Many stem cell types, such as mesenchymal stem cells (MSCs), embryonic stem cells (ESC), derived oligodendrocyte precursor cells, fetal-derived neural stem cells, and central nervous system stem cells, have been tested or are currently undergoing clinical testing for the treatment of spinal cord injury. Thus far, MSCs have been mainly used for the treatment of SCI. Due to their ability to elude the host immune system, MSCs, both autologous and allogeneic, have been utilized. [1] They are separated from the umbilical cord (UC-MSCs), adipose tissue (ADSCs), and bone marrow (BMSCs).¹

Mesenchymal stem cell therapy for spinal cord injury

At the site of injury, neurons and glial cells will undergo apoptosis due to the severe inflammation and the toxins released. glial scar will form encircling the lesion's perimeter. Fibrotic scarring results from the migration of Schwann cells and fibroblasts to the lesion's center where they secrete collagen, fibronectin, and laminin, among other ECM proteins. Early on, glial scars will aid in reducing inflammation and blood regrowth while obstructing the entry of toxins into the tissues. Nevertheless, as the injury progresses, glial and fibrotic scars both inhibit neuronal regeneration. Since MSCs contain specialized factors, they are used to treat this severe injury. [1] According to recent research, MSCs secrete a wide variety of bioactive molecules including GM-CSF, VEGF, HGF, IGF-I, stanniocalcin-1, and TGF-β. that aid in the repair of damaged neurons and oligodendrocytes. Along with other factors secreted by the MSCs, angiogenesis is stimulated followed by proliferation and regeneration. This is accomplished by lowering inflammation, lessening damage to the remaining tissue, and preventing gliosis, which enhances the extracellular matrix's environment. The cells' unique characteristics aid in healing and regeneration once they are applied to the site of injury.¹