Grant: Operating Grant

Immune cells travel from the blood to sites of inflammation where they initiate and maintain tissue damage. Normally, the brain is not easily accessible to cells of the immune system due to the presence of the endothelial blood-brain barrier (BBB). However, in the disease Multiple Sclerosis (MS), a large number of immune cells known as TH1 and TH17 lymphocytes readily cross the BBB to infiltrate the brain and eventually lead to the formation of multiple brain lesions. The movement of such aggressive immune cells from the blood to the CNS is orchestrated by many factors, including pro-inflammatory cytokines that enable immune cells to open the BBB. We have identified interleukin (IL)-26 as a novel cytokine expressed by aggressive TH17 lymphocytes, and found it to play a central role in the migration of these lesion-forming and aggressive immune cells into the brain. This research focuses on this newly discovered molecule used by immune cells to enter the brain and to promote the development of MS lesions. This project expands our research program which aims at identifying attractive targets for the development of novel therapies for the treatment of MS and other inflammatory diseases.