Fig. 8.

Dynamic coordination of BEC–pericyte communication by CD146 controls BBB formation during embryogenesis. At the initial stage of BBB development, CD146 expression in the cerebrovascular ECs promotes barrier induction by up-regulating claudin-5. Subsequently, pericyte-expressed CD146 functions as a coreceptor of PDGFRβ to recruit pericytes to BECs. Following the pericyte recruitment and attachment, endothelial CD146 is finally down-regulated by pericyte-derived TGF-β1, contributing to further BBB maturation.