title: Bone marrow-derived progenitor cells prevent thrombin-induced increase in lung vascular permeability.
abstract: Since thrombin activation of endothelial cells (ECs) is well-known to increase endothelial permeability by disassembly of adherens junctions (AJs) and actinomyosin contractility mechanism involving myosin light chain (MLC) phosphorylation, we investigated the effects of bone marrow-derived progenitor cells (BMPCs) on the thrombin-induced endothelial permeability response. We observed that addition of BMPCs to endothelial monolayers at a fixed ratio prevented the thrombin-induced decrease in transendothelial electrical resistance, a measure of AJ integrity, and increased mouse pulmonary microvessel filtration coefficient, a measure of transvascular liquid permeability. The barrier protection was coupled to increased vascular endothelial cadherin expression and increased Cdc42 activity in ECs. Using small interfering RNA (siRNA) to deplete Cdc42 in ECs, we demonstrated a key role of Cdc42 in signaling the BMPC-induced endothelial barrier protection. Endothelial integrity induced by BMPCs was also secondary to inhibition of MLC phosphorylation in ECs. Thus BMPCs interacting with ECs prevent thrombin-induced endothelial hyperpermeability by a mechanism involving AJ barrier annealing, inhibition of MLC phosphorylation, and activation of Cdc42.
authors.affiliation: Department of Pharmacology, Center for Lung and Vascular Biology, University of Illinois College of Medicine, 835 S. Wolcott Ave., Rm. E403-MSB, Chicago, IL 60612, USA. yyzhao@uic.edu
authors.forename: Yidan D
authors.initials: YD
authors.lastname: Zhao
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ohkawara
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Vogel
authors.forename: Asrar B
authors.initials: AB
authors.lastname: Malik
authors.forename: You-Yang
authors.initials: YY
authors.lastname: Zhao
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000378:metabolism; D001854:Bone Marrow Cells / Q000166:cytology* / Q000201:enzymology; D015820:Cadherins / Q000378:metabolism; D002199:Capillary Permeability / Q000187:drug effects*; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D017097:Electric Impedance; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects / Q000201:enzymology; D004789:Enzyme Activation / Q000187:drug effects; D006801:Humans; D008168:Lung / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism*; D051379:Mice; D018994:Myosin Light Chains / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D013234:Stem Cells / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism*; D013917:Thrombin / Q000494:pharmacology*; D020764:cdc42 GTP-Binding Protein / Q000378:metabolism; D020742:rhoA GTP-Binding Protein / Q000378:metabolism; D000099152:Cadherin 5
chemical_list: D015703:Antigens, CD; D015820:Cadherins; D018994:Myosin Light Chains; D013917:Thrombin; D020764:cdc42 GTP-Binding Protein; D020742:rhoA GTP-Binding Protein; D000099152:Cadherin 5