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Endothelial Cadherin Endothelium Is Regulated by Vascular Progenitor Migration of Human Hematopoietic Progenitor Cells Across Bone Marrow Endothelium Is Regulated by Vascular Endothelial Cadherin This information is current as of October 1, 2021. Jaap D. van Buul, Carlijn Voermans, Veronique van den Berg, Eloise C. Anthony, Frederik P. J. Mul, Sandra van Wetering, C. Ellen van der Schoot and Peter L. Hordijk J Immunol 2002; 168:588-596; ; doi: 10.4049/jimmunol.168.2.588 http://www.jimmunol.org/content/168/2/588 Downloaded from References This article cites 54 articles, 33 of which you can access for free at: http://www.jimmunol.org/content/168/2/588.full#ref-list-1 http://www.jimmunol.org/ Why The JI? Submit online. • Rapid Reviews! 30 days* from submission to initial decision • No Triage! Every submission reviewed by practicing scientists • Fast Publication! 4 weeks from acceptance to publication by guest on October 1, 2021 *average Subscription Information about subscribing to The Journal of Immunology is online at: http://jimmunol.org/subscription Permissions Submit copyright permission requests at: http://www.aai.org/About/Publications/JI/copyright.html Email Alerts Receive free email-alerts when new articles cite this article. Sign up at: http://jimmunol.org/alerts The Journal of Immunology is published twice each month by The American Association of Immunologists, Inc., 1451 Rockville Pike, Suite 650, Rockville, MD 20852 Copyright © 2002 by The American Association of Immunologists All rights reserved. Print ISSN: 0022-1767 Online ISSN: 1550-6606. Migration of Human Hematopoietic Progenitor Cells Across Bone Marrow Endothelium Is Regulated by Vascular Endothelial Cadherin1 Jaap D. van Buul,* Carlijn Voermans,* Veronique van den Berg,* Eloise C. Anthony,* Frederik P. J. Mul,* Sandra van Wetering,* C. Ellen van der Schoot,*† and Peter L. Hordijk2* The success of stem cell transplantation depends on the ability of i.v. infused stem cells to engraft the bone marrow, a process referred to as homing. Efficient homing requires migration of CD34؉ cells across the bone marrow endothelium, most likely through the intercellular junctions. In this study, we show that loss of vascular endothelial (VE)-cadherin-mediated endothelial cell-cell adhesion increases the permeability of monolayers of human bone marrow endothelial cells (HBMECs) and stimulates the ؉ transendothelial migration of CD34 cells in response to stromal cell-derived factor-1␣. Stromal cell-derived factor-1␣-induced Downloaded from migration was dependent on VCAM-1 and ICAM-1, even in the absence of VE-cadherin function. Cross-linking of ICAM-1 to mimic the leukocyte-endothelium interaction induced actin stress fiber formation but did not induce loss of endothelial integrity, whereas cross-linking of VCAM-1 increased the HBMEC permeability and induced gaps in the monolayer. In addition, VCAM- 1-mediated gap formation in HBMEC was accompanied by and dependent on the production of reactive oxygen species. These data suggest that modulation of VE-cadherin function directly affects the efficiency of transendothelial migration of CD34؉ cells and that activation of ICAM-1 and, in particular, VCAM-1 plays an important role in this process through reorganization of the http://www.jimmunol.org/ endothelial actin cytoskeleton and by modulating the integrity of the bone marrow endothelium through the production of reactive oxygen species. The Journal of Immunology, 2002, 168: 588–596. ematopoietic stem cell transplantation is applied to re- Fusin, leukocyte-derived seven-transmembrane domain receptor, store hematopoiesis in cancer patients after myelo-abla- or CXCR-4 (6–9). SDF-1␣-driven homing of CD34ϩ cells has H tive chemotherapy and/or after irradiation. The success been suggested to be a multistep process similar to the extravasa- of the transplantation depends on the ability of the hematopoietic tion process of leukocytes at inflammatory sites (10) and is medi- stem cells to engraft the bone marrow, a process referred to as ated by adhesion molecules both on CD34ϩ cells (11) and on bone by guest on October 1, 2021 homing (1). An important step in homing is the actual transmigra- marrow endothelial cells. In the final stage of homing, CD34ϩ tion of reinfused stem cells across the bone marrow endothelium to cells migrate across the bone marrow endothelium, presumably via the bone marrow stroma. Although much is known about the mi- the intercellular junctions. Therefore, endothelial cell-cell adhe- gration of granulocytes and T cells, the factors that control the sion is most likely an important regulatory factor in the homing of transendothelial migration of hematopoietic stem cells are still CD34ϩ cells. poorly understood. Endothelial cell-cell adhesion is largely dependent on the ho- Recently, the first powerful chemoattractant for hematopoietic motypic cell-cell adhesion molecule vascular endothelial (VE)- ϩ stem cells (CD34 cells) has been described and identified as stro- cadherin (cadherin-5, CD144). VE-cadherin is a transmembrane mal cell-derived factor-1␣ (SDF-1␣).3 SDF-1␣ is produced by protein that, like other members of the cadherin family (12), as- several types of stromal cell, including those of the bone marrow sociates via its cytoplasmic tail with various cytosolic proteins, (2–5), and signals through a G protein-coupled receptor called including ␣-, ␤-, and ␥-catenin (plakoglobin) and p120/p100. These proteins link VE-cadherin to the cortical actin cytoskeleton *Department of Experimental Immunohematology, CLB and Laboratory for Exper- (13–15). The role of VE-cadherin in leukocyte transendothelial imental and Clinical Immunology, and †Department of Hematology, Academic Med- migration was first described by Gotsch et al. (16), who showed an ical Center, University of Amsterdam, Amsterdam, The Netherlands accelerated extravasation of neutrophils in a mouse peritonitis Received for publication July 23, 2001. Accepted for publication November 16, 2001. model in vivo upon i.v. injection of a mAb against mouse VE- The costs of publication of this article were defrayed in part by the payment of page cadherin. Transfection experiments and gene inactivation studies charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact. have shown that VE-cadherin expression reduces monolayer per- 1 This work was supported by Dutch Cancer Society Grants CLB99-2000 (to J.D.v.B. meability and promotes cell aggregation, motility, and growth, and and E.C.A.) and CLB2001-2544 (to C.V.) and by Landsteiner Foundation for Blood that VE-cadherin is required for the organization of vascular-like Transfusion Research Grant 9910 (to F.P.J.M. and S.v.W.). structures in embryoid bodies (17–19). Moreover, VE-cadherin, 2 Address correspondence and reprint requests to Dr. Peter L. Hordijk, Department of together with ␤-catenin, seems to be involved in cell survival (20). Experimental Immunohematology, CLB, Academic Medical Center, University of Amsterdam, Plesmanlaan 125, 1066 CX, Amsterdam, The Netherlands. E-mail ad- Regulation of VE-cadherin, and thereby of endothelial cell-cell dress: [email protected] adhesion, may occur through tyrosine or serine phosphorylation 3 Abbreviations used in this paper: SDF-1␣, stromal cell-derived factor-1␣; VE, vas- (21–24), association with regulatory proteins (20), and modulation cular endothelial; HBMEC, human bone marrow endothelial cell; CB, cord blood; PB, of the endothelial actin cytoskeleton (17, 25). In addition, several peripheral blood; ROS, reactive oxygen species; G␣M-Ig, goat anti-mouse Ig; FN, fibronectin; N-AC, N-acetyl-cysteine; F-actin, filamentous actin; DHR, di-hydro-rho- studies have proposed a role for leukocyte adhesion-induced sig- damine-1,2,3; VLA, very late Ag. naling, e.g., through activation of myosin light chain kinase in the Copyright © 2002 by The American Association of Immunologists 0022-1767/02/$02.00 The Journal of Immunology 589 endothelial cells, which may indirectly regulate VE-cadherin func- cells from CB and Ͼ90% of the cells from PB expressed CD34 as deter- tion in the process of transendothelial migration (26–29). mined by FACS analysis with a CD34 Ab (no. 581; Immunotech). A role for specific adhesion molecules in endothelial cell sig- naling has been suggested by studies on VCAM-1 (CD106) and Cell cultures ICAM-1 (CD54). Lorenzon et al. (30) concluded that VCAM-1 The HBMEC line has been described previously (33). The cells were cul- and endothelial selectins, in addition to their role as adhesion re- tured in FN-coated culture flasks (Nunc, Roskilde, Denmark; Life Tech- ceptors, mediate endothelial stimulation by adherent leukocytes. nologies) in Medium 199 (Life Technologies) supplemented with 10% Moreover, activation of ICAM-1 on endothelial cells after binding (v/v) pooled, heat-inactivated human serum, 10% (v/v) heat-inactivated ␮ of T cells has been reported to induce tyrosine phosphorylation of FCS, 1 ng/ml basic fibroblast factor, 5 U/ml heparin, 300 g/ml glutamine, 100 U/ml penicillin, and 100 ␮g/ml streptomycin. After reaching conflu- the actin-binding protein cortactin (31). In line with this observa- ency, the cells were passaged by treatment with trypsin/EDTA (Life Tech- tion, it was suggested that ICAM-1 mediates cell shape changes nologies). In all experiments, HBMEC monolayers were pretreated with through coupling to the p21Rho GTPase and by inducing phos- IL-1␤ for 4 h. HL-60 and KG-1a cell lines were obtained from the Amer- phorylation of cytoskeletal proteins and transcription factors (32). ican
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