Grant: CIHR Fellowship

Multiple Sclerosis (MS) is an inflammatory disease of the Central Nervous System (CNS), mainly affecting young adults. This disease is the consequence of a disorder of the immune system at the origin of myelin lesions, thus disrupting the propagation of the nervous impulse. A key element in the formation of demyelinating lesions is the entry of immune cells into the CNS. Indeed, the CNS is normally protected by barriers formed by vascular structures. To date, the molecular mechanisms that allow the entry of these cells, named the transmigration, remain unclear. B lymphocytes, a subset of immune cells, seem to have a fundamental role in the pathophysiology of MS. One way to prevent the formation of myelin lesions would be to prevent their transmigration within the CNS. The objective of this work is to study the interactions of B cells with the barriers of the CNS in healthy individuals and in MS patients. For this, we will first characterize the expression of molecules involved in the transmigration by the different populations of B lymphocytes. Then, we will study the ability of these cells to enter into the CNS through these barriers using animal models of the disease.