MCAM and multiple sclerosis: Recently, we reported that CD146 is a mediator of the interplay between endothelial cells and pericytes, promoting BBB development.17 During conditions of neuroinflammation, such as in multiple sclerosis (MS), CD146 is upregulated on BBBECs and promotes the transmigration of inflammatory cells into the CNS.18 In addition, CD146 is also expressed on some proinflammatory cells, such as T cells19 and macrophages,20 which are associated with the development of inflammation.