Astrocyte-mediated induction of tight junctions in brain capillary endothelium: an efficient in vitro model.
Fourth passage rat brain capillary endothelial cell cultures, which no longer possess the tight junctions characteristic of this highly specialized component of the blood-brain barrier, were used to study induction of zonulae occludentes in vitro. These cells, when grown in 50% rat brain astrocyte-conditioned medium and 50% alpha-MEM on an endothelial cell matrix-coated substrate (Cedarlane Labs, Hornby, Ont.), possessed numerous, elaborately complex, tight junctions which were identical to those displayed in vivo by intact brain capillary endothelium. Endothelial cells grown in 50% astrocyte-conditioned medium and 50% alpha-MEM on bare plastic or fibronectin-coated substrate, possessed no tight junctions. Results of this study clearly demonstrate the local control of tight junction biogenesis in brain capillary endothelial cells depends on: (1) an astrocyte-produced factor(s), and (2) a 'competent' (cell-produced) extracellular matrix.
Arthur
F E
FE
Department of Zoology, University of Western Ontario, London, Canada.
Shivers
R R
RR
Bowman
P D
PD
D000818:Animals; D001253:Astrocytes / Q000502:physiology*; D001812:Blood-Brain Barrier; D001921:Brain / Q000098:blood supply* / Q000648:ultrastructure; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000502:physiology* / Q000648:ultrastructure; D007365:Intercellular Junctions / Q000502:physiology*; D008959:Models, Neurological; D051381:Rats