Recently researchers discovered an axon guidance protein known as Plexin B2 in the central nervous system (CNS). During the spinal cord injury, this protein plays a significant role in the healing of the wound and neural repair.
The experiment was designed and conducted by the Icahn School of Medicine at Mount Sinai. This study could help the development of the treatments or therapies which target axon guidance pathways for treating the patients of Spinal cord injury more effectively.
the complete study findings are published in the journal “Nature Neuroscience.”
The spinal cord is a soft tissue of the body and is normally protected by vertebrae. Sometimes they can be dislocated or broken down through many ways that create the damaging pressure on the spinal cord. Injuries in the spinal cord can occur at any level.
Which body function will be compromised or lost depends on the severity of damage to the nervous tissue and segment of the cord that is injured. Injury to the spinal cord induces any physiological changes to the different parts of the body that are controlled by the nerves.
When the spinal cord injury occurs it damages a few, several or approximately all the axons of the spinal cord that are located at the site of injury. Many other cells that are present around the injury site may also die.
The injuries in which little or no nerve cell is damaged and only pressure induce blockage of nerve signaling or demyelination of axons result then complete recovery is possible. The injury in which nerve cells are completely damaged even at a small horizontal level then the paralysis results and recovery is impossible at this stage.
When the spinal cord injury results than for repairing, the tissue immune cells and glial cells start to move at this site which forms a protective barrier around the wound. It facilitates the clearing of debris from the wound and inflammation results.
A barrier is built through a process known as corralling wherein microglia and macrophages which separates the narcotic tissue from the healthy tissues. In this study, researchers found that at the early stage of the healing process this corralling wherein microglia begin, and it requires Plexin B2 protein as it stimulates the movement of immune cells to the site of injury.
If the Plexin B2 in the macrophages and microglia are absent then it impaired the corralling process and it leads to inflammation spillover, tissue damage and hindered the regeneration of axon ( it is slender part of the nerve cell which involved in the transmission of nerve impulse).
Hongyan Jenny Zou who is a professor of Neurosurgery and Neuroscience at the Ichan School of Medicine at Mount Sinai and a lead investigator said that in the spatial organization of the glial cells the role of macrophages and microglia around the site of injury through an axon guidance receptors is quite unexpected.
In the central nervous system process of tissue repair relies on a coordinated response from many cell types during the overlapping phases. Due to this complex system, it becomes difficult to differentiate the roles of specific glial cells.
Previously Scientists assumed that astrocytes are the main cells that drive the corralling process. Astrocytes involve in supporting the glial cells. This study identifies the role of microglia and macrophages which become activated due to spinal cord injury. It also identifies the function of Plexin B2 proteins in the corralling.
After spinal cord injury and traumatic brain injuries, Improvements have seen in neural repair by understanding the signaling pathways and glial cell interactions with each other and the injury.