Table 2.

Factors released from endothelial cells in a polarized manner.

Compound	Side of release or localization	Experimental conditions	Modulation of release or localization	References
Basement membrane components: collagen IV, fibronectin, metalloproteinases	Basolateral	Bovine aortic arch endothelial cells		98
IL-1α, IL-6, IL-10, TNF, GM-CSF	Apical > basolateral	Mouse brain endothelial cells	LPS stimulates apical IL-6 release more when added to the apical than to the basolateral side	96
IL-6	Basolateral	Rat brain microvascular endothelial cells cocultured with astrocytes after flow cessation	Reperfusion	99
IL-8, GM-CSF	Apical	Human dermal microvascular endothelial cells		100
MIC-1 (GDF15)	Basolateral
von Willebrand factor (vWF)	Basolateral	Human umbilical vein endothelial cells (HUVEC)	Calcium ionophore or phorbol myristate stimulate basolateral release (constitutive secretion was not polarized)	101
Platelet-derived growth factor (PDGF)	Basolateral	Bovine aortic endothelial cells on nitrocellulose membranes		102
Cholesterol	Basolateral	Porcine brain capillary endothelial cells	Cholesterol acceptors	97
24(S)-OH cholesterol	Apical		HDL3
Endothelin-1	Basolateral > apical	HUVEC on amniotic membranes; bovine brain capillary endothelial cells on collagen-coated Millicell CM inserts	Dexamethasone reduces apical secretion	103,104
Glial cell-derived neurotrophic factor (GDNF)	Basolateral	Mouse brain endothelial cell line MBEC4 transfected with expression vector		105
CCL2	Apical > basolateral	Human brain microvessel endothelial cells	TNF + Interferon γ enhance binding to basolateral membrane	106
CCL3	Basolateral > apical		TNF + Interferon γ enhance binding to apical membrane
SDF1 (CXCL12)	Basolateral/abluminal	Human hCMEC/D3 cells, mice in vivo	Inflammation, S1PR2 signaling, female gender are associated with apical/luminal localization	107
Beta-hexosaminidase	Basolateral	Human hCMEC/D3 cells		13