title: Short-term fibronectin treatment induces endothelial-like and angiogenic properties in monocyte-derived immature dendritic cells: involvement of intracellular VEGF and MAPK regulation.
abstract: Fibronectin (FN) is an extracellular matrix protein promoting cell proliferation, adhesion, and survival and is localized in the intimal layer of normal and atherosclerotic blood vessels. Dendritic cells (DCs) are potent antigen-presenting cells located in healthy and diseased intima, and thus may predispose arteries to atherosclerosis. Besides their pro-atherogenic activities DCs can promote neovascularization, by releasing pro-angiogenic mediators and/or by trans-differentiating into endothelial-like cells. Here, we investigated changes in morphology, function and angiogenic properties of monocyte-derived immature DCs (Mo-iDCs) after a short-term FN treatment and some of the signaling pathways involved in these processes. The cells were analyzed by time-lapse, confocal microscopy and flow cytometry. Within 90 min of re-plating, FN induced a swift morphologic transformation of most round iDCs into spindle-shaped iDCs (sp-iDCs). This was characterized by redistribution of mitochondria into dendritic spindles, decreased CD1c, and increased thrombomodulin (CD141) expression. Functionally, sp-iDCs acquired Ulex-europaeus-agglutinin-1 lectin binding, phagocytosis was decreased and intracellular (nuclear and cytosolic) vascular endothelial growth factor (VEGF) was increased. FN also induced ERK1/2 phosphorylation in round-iDCs, and p38MAPK phosphorylation in sp-iDCs. Inhibiting p38MAPK, but not ERK1/2, restrained the FN-induced transformation into sp-iDCs. Furthermore, FN-treatment of Mo-iDCs induced a paracrine angiogenic effect on endothelial tube formation, which was abolished by inhibiting ERK1/2 or VEGF. Inhibiting p38MAPK had no effect on endothelial tube formation. By contrast, in laminin-treated Mo-iDCs, which had round-shaped morphology, CD1c and CD141 expression was similar to control untreated cells, but intracellular VEGF levels were higher, and endothelial tube formation was an individual trait. We conclude that a short-term FN treatment induced angiogenic intracrine and paracrine properties in Mo-iDCs. This may act as an immediate protective mechanism to maintain vascular homeostasis. Moreover, inducing sp-iDCs by short term FN-treatment or ERK1/2 modulation might be considered as new approaches for regulating angiogenesis through the production/inhibition of pro-angiogenic mediators. Collectively, these findings may support a role for FN and Mo-iDCs in vascular function and angiogenesis.
authors.affiliation: The Lloyd Rigler Sleep Apnea Research Laboratory, Unit of Anatomy and Cell Biology, The Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
authors.forename: Slava
authors.initials: S
authors.lastname: Berger
authors.forename: Larissa
authors.initials: L
authors.lastname: Dyugovskaya
authors.forename: Andrey
authors.initials: A
authors.lastname: Polyakov
authors.forename: Lena
authors.initials: L
authors.lastname: Lavie
mesh_terms: D000328:Adult; D018949:Antigens, CD1 / Q000378:metabolism; D002070:Butadienes / Q000494:pharmacology; D048430:Cell Shape / Q000187:drug effects / Q000502:physiology; D017077:Culture Media, Conditioned / Q000378:metabolism; D003713:Dendritic Cells / Q000166:cytology / Q000502:physiology*; D042783:Endothelial Cells / Q000187:drug effects / Q000502:physiology; D005353:Fibronectins / Q000378:metabolism / Q000494:pharmacology*; D005434:Flow Cytometry; D006023:Glycoproteins / Q000378:metabolism; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D020935:MAP Kinase Signaling System; D008297:Male; D008928:Mitochondria / Q000378:metabolism; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D009000:Monocytes / Q000187:drug effects* / Q000502:physiology; D018919:Neovascularization, Physiologic; D009570:Nitriles / Q000494:pharmacology; D010587:Phagocytosis; D010641:Phenotype; D010766:Phosphorylation; D011725:Pyridines / Q000494:pharmacology; D018180:Thrombomodulin / Q000378:metabolism; D013997:Time Factors; D059008:Time-Lapse Imaging; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism; D055815:Young Adult; D048051:p38 Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D018949:Antigens, CD1; D002070:Butadienes; C437944:CD1C protein, human; D017077:Culture Media, Conditioned; D005353:Fibronectins; D006023:Glycoproteins; D007093:Imidazoles; D009570:Nitriles; D011725:Pyridines; C546931:THBD protein, human; D018180:Thrombomodulin; C113580:U 0126; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; C535150:MAPK1 protein, human; D019950:Mitogen-Activated Protein Kinase 1; D048051:p38 Mitogen-Activated Protein Kinases; C090942:4-(4-fluorophenyl)-2-(4-hydroxyphenyl)-5-(4-pyridyl)imidazole