Additional progress in myelin repair
In 2015, Dr Holly Cate was awarded an MS Research Australia project grant, supported by the Trish MS Research Foundation.
Nerve cells are similar to electric cables, and are covered in a protective, insulating, coating called myelin. In MS, this myelin sheath is damaged leading to the relapses and disability progression associated with the disease. Regrowth of myelin can occur and is necessary to restore and maintain nerve functioning and to slow the progressive course of MS.
Around MS lesions in the brain, chemicals are present (as a result of the inflammation and scarring) which inhibit the growth and repair of myelin. One of these chemicals is called BMP. In a laboratory model of MS, BMP was found to stop the production of myelin. Dr Holly Cate discovered that BMP doesn’t directly affect the cells responsible for making myelin (called oligodendrocytes), but rather it interacts with other brain support cells called astrocytes. The astrocytes then in turn produce factors that reduce the amount of myelin produced by oligodendrocytes.
After completing this first part of the MS Research Australia project grant, supported by the Trish Foundation, Dr Cate left the laboratory to take up another role, however, this important work was continued by a PhD student, Alistair Cole. Alistair looked more deeply at a particular BMP molecule, called BMP4. He found that BMP4 activates astrocytes and increase their numbers, which in turn reduces the ability of oligodendrocytes to mature and produce myelin.
Alistair is now completing his PhD thesis and the research team are continuing to identify the specific molecules secreted by the astrocytes that prevent oligodendrocyte maturation.
These findings are important in the efforts to develop new therapeutic strategies to complement immune therapies that stop the inflammation. Stopping the damage done by the immune attack and then enhancing repair are both critically important in completing stopping and reversing the damaging effects of MS. Restoring myelin will help reverse the symptoms of MS, and in the longer term protect the vulnerable nerve fibres to prevent permanent disability.