Scientists have discovered that specific immune system cells are key players in brain repair. The discovery means that researchers can now use this new knowledge to develop medicines which will boost these particular cells and develop an entirely new class of treatments for the future.
 
The research study, by scientists at the Institute for Experimental Medicine at Queen’s University Belfast, Ireland, uncovered beneficial effects of immune cells in myelin repair that have potential to reverse myelin damage. The research shows that a protein made by certain cells within the immune system triggers the brain’s stem cells to mature into oligodendrocytes that repair myelin.
 
In a mouse-model study, researchers found that regulatory T-cells (Treg) promote oligodendrocyte differentiation, along with myelination and remyelination. Treg-deficient mice showed substantially impaired remyelination and oligodendrocyte differentiation, which was repaired by an adoptive transfer of Treg. In brain slice cultures, Treg accelerated developmental myelination and remyelination, even in the absence of obvious inflammation. Treg directly promoted oligodendrocyte progenitor cell differentiation and myelination in vitro. Researchers identified CCN3 as a Treg-derived mediator of oligodendrocyte differentiation and myelination in vitro. These findings show a new regenerative function of Treg in the central nervous system, which is distinct from immunomodulation.
 
Results of mouse model studies sometimes do not translate to humans and may be years away from being a marketable treatment. However, the researchers argue that this knowledge is essential to designing future treatments that tackle neurological diseases, such as MS, in a new way – repairing damage rather than only reducing attacks. In the future, combining these approaches will deliver better outcomes for patients.

The study was published in the journal Nature Neuroscience.