A proposed model for the multistep adhesive cascade involved in the capture, arrest, and diapedesis of T blasts across resting CNS vasculature and the subsequent recruitment of mononuclear cells to the inflamed CNS. Analogous adhesive interactions that support constitutive immature dendritic cell rolling on resting skin vasculature are also shown. Antigenic stimulation in the CNS triggers both endothelial and extravascular traffic signals for subsets of effector leukocytes incapable of extravasating the resting CNS vasculature. Question marks indicate where the involvement of chemokines is still unknown.