title: Vascular endothelial growth factor modulates neutrophil transendothelial migration via up-regulation of interleukin-8 in human brain microvascular endothelial cells.
abstract: Hypoxia, a strong inducer for vascular endothelial growth factor (VEGF)/vascular permeable factor (VPF) expression, regulates leukocyte infiltration through the up-regulation of adhesion molecules and chemokine release. To determine whether VEGF/VPF is directly involved in chemokine secretion, we analyzed its effects on chemokine expression in human brain microvascular endothelial cells (HBMECs) by using a human cytokine cDNA array kit. Cytokine array analysis revealed a significant increase in expression of monocyte chemoattractant protein-1 and the chemokine receptor CXCR4 in HBMECs, a result similar to that described previously in other endothelial cells. Interestingly, we also observed that VEGF/VPF induced interleukin-8 (IL-8) expression in HBMECs and that IL-8 mRNA was maximal after 1 h of VEGF/VPF treatment of the cells. Enzyme-linked immunosorbent assay data and immunoprecipitation analysis revealed that although VEGF/VPF induced IL-8 expression at the translational level in HBMECs, basic fibroblast growth factor failed to induce this protein expression within 12 h. VEGF/VPF increased IL-8 production in HBMECs through activation of nuclear factor-KB via calcium and phosphatidylinositol 3-kinase pathways, whereas the ERK pathway was not involved in this process. Supernatants of the VEGF/VPF-treated HBMECs significantly increased neutrophil migration across the HBMEC monolayer compared with those of the untreated control. Furthermore, addition of anti-IL-8 antibody blocked this increased migration, indicating that VEGF/VPF induced the functional expression of IL-8 protein in HBMECs. Taken together, these data demonstrate for the first time that VEGF/VPF induces IL-8 expression in HBMECs and contributes to leukocyte infiltration through the expression of chemokines, such as IL-8, in endothelial cells.
authors.affiliation: Division of Experimental Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts 02115, USA.
authors.forename: Tae-Hee
authors.initials: TH
authors.lastname: Lee
authors.forename: Hava
authors.initials: H
authors.lastname: Avraham
authors.forename: Seung-Hoon
authors.initials: SH
authors.lastname: Lee
authors.forename: Shalom
authors.initials: S
authors.lastname: Avraham
mesh_terms: D000256:Adenoviridae / Q000378:metabolism; D015153:Blotting, Western; D001921:Brain / Q000098:blood supply* / Q000166:cytology; D002118:Calcium / Q000378:metabolism; D002465:Cell Movement; D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000096:biosynthesis; D054377:Chemokine CXCL12; D019743:Chemokines, CXC / Q000096:biosynthesis; D003513:Cycloheximide / Q000494:pharmacology; D018076:DNA, Complementary / Q000378:metabolism; D016228:Endothelial Growth Factors / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000166:cytology* / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D016209:Interleukin-8 / Q000096:biosynthesis* / Q000235:genetics; D008222:Lymphokines / Q000378:metabolism*; D008833:Microcirculation; D016328:NF-kappa B / Q000378:metabolism; D009504:Neutrophils / Q000166:cytology* / Q000378:metabolism; D011233:Precipitin Tests; D014176:Protein Biosynthesis; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D019718:Receptors, CXCR4 / Q000096:biosynthesis; D013997:Time Factors; D015854:Up-Regulation; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors
chemical_list: C515255:CXCL12 protein, human; D018932:Chemokine CCL2; D054377:Chemokine CXCL12; D019743:Chemokines, CXC; D018076:DNA, Complementary; D016228:Endothelial Growth Factors; D016209:Interleukin-8; D008222:Lymphokines; D016328:NF-kappa B; D011500:Protein Synthesis Inhibitors; D019718:Receptors, CXCR4; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D003513:Cycloheximide; D002118:Calcium