Figure 2.

JAML support leukocyte migration across the BBB. (A and B) Expression of JAML (green) on CD14+ monocytes and CD8 T cells adhering to primary cultures of human BBB‐ECs. Costaining for p120 – ICAM‐1 (red) and nuclei (blue) are included. Y‐Z projections show JAML enhancement surrounding the leukocytes in transmigratory cups. Data shown are representative of four independent experiments. Scale bar = 10 μm. (C and D) Human ex vivo CD14 monocytes and activated CD8 T cells were allowed to migrate for 18 h across a monolayer of primary human BBB‐ECs pretreated with isotype control or anti‐JAML antibody. JAML blockade significantly restricted the migration of CD14 monocytes and activated CD8 T cells across BBB‐ECs. Data shown are representative of three independent experiments (n = 3 and 6 blood donors) performed in triplicate using two distinct BBB‐EC preparations (***P < 0.001). JAML, junctional adhesion molecule‐like; BBB‐ECs, blood–brain barrier endothelial cells.