Pre-B-cell-colony-enhancing factor is critically involved in thrombin-induced lung endothelial cell barrier dysregulation.
Prior genomic and genetic studies identified pre-B-cell colony-enhancing factor (PBEF) as a novel candidate gene and biomarker in acute lung injury (ALI). As increased vascular permeability is a cardinal feature of ALI, we assessed the role of PBEF in in vitro vascular barrier regulation using confluent human pulmonary artery endothelial cell (HPAEC) monolayers. Reductions in PBEF protein expression (>70%) by siRNA significantly attenuated EC barrier dysfunction induced by the potent edemagenic agent, thrombin, reflected by reductions in transendothelial electric resistance (TER, approximately 60% reduction). Furthermore, PBEF siRNA blunted thrombin-mediated increases in Ca(2+) entry, polymerized actin formation, and myosin light chain phosphorylation, events critical to the thrombin-mediated permeability response. Finally, PBEF siRNA also significantly inhibited thrombin-stimulated increase of IL-8 secretion in HPAEC, a chemokine known to induce actin fiber formation and intercellular gap formation of endothelial cells. Taken together, these studies demonstrate that PBEF may be required for complete expression of the thrombin-induced inflammatory response and reveal potentially novel role for PBEF in the regulation of EC Ca(2+)-dependent cytoskeletal rearrangement and endothelial barrier dysfunction. Ongoing studies will continue to address the molecular mechanisms by which PBEF contributes to ALI susceptibility.
Ye
Shui Q
SQ
Department of Medicine, Section of Pulmonary/Critical Care, University of Chicago Pritzker School of Medicine, 5841 S. Maryland Avenue, MC 6076, Chicago, IL 60637, USA. sye1@medicine.bsd.uchicago.edu
Zhang
Li Q
LQ
Adyshev
Djanybek
D
Usatyuk
Peter V
PV
Garcia
Alexander N
AN
Lavoie
Tera L
TL
Verin
Alexander D
AD
Natarajan
Viswanathan
V
Garcia
Joe G N
JG
D000199:Actins / Q000737:chemistry; D001402:B-Lymphocytes / Q000378:metabolism*; D001483:Base Sequence; D015415:Biomarkers; D015153:Blotting, Western; D002118:Calcium / Q000378:metabolism; D002478:Cells, Cultured; D018925:Chemokines / Q000378:metabolism; D016207:Cytokines / Q000502:physiology*; D003599:Cytoskeleton / Q000378:metabolism; D017097:Electric Impedance; D042783:Endothelial Cells / Q000166:cytology* / Q000378:metabolism; D004730:Endothelium, Vascular / Q000166:cytology* / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D020868:Gene Silencing; D006801:Humans; D007249:Inflammation; D016209:Interleukin-8 / Q000378:metabolism; D008168:Lung / Q000473:pathology*; D008833:Microcirculation; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D054409:Nicotinamide Phosphoribosyltransferase; D010766:Phosphorylation; D011651:Pulmonary Artery / Q000166:cytology; D034741:RNA, Small Interfering / Q000378:metabolism; D013917:Thrombin / Q000737:chemistry / Q000378:metabolism*; D013997:Time Factors; D014162:Transfection
D000199:Actins; D015415:Biomarkers; D018925:Chemokines; D016207:Cytokines; D016209:Interleukin-8; D034741:RNA, Small Interfering; D054409:Nicotinamide Phosphoribosyltransferase; C085455:nicotinamide phosphoribosyltransferase, human; D013917:Thrombin; D002118:Calcium