Objective—

Deleted in malignant brain tumors 1 (DMBT1) belongs to the scavenger receptor cysteine-rich superfamily of proteins and is implicated in innate immunity, cell polarity, and differentiation.

Here we studied the role of DMBT1 in endothelial cells.

Methods and Results—

DMBT1 was secreted into the extracellular matrix (ECM) by endothelial cells in vitro and in situ and the presence of DMBT1 in the ECM increased endothelial cell adherence.

Endothelial cell-derived DMBT1 associated with galectin-3 (coprecipitation), and human recombinant DMBT1 bound EGF, vascular endothelial growth factor and Delta-like (Dll) 4 (specific ELISAs).

Compared to cells from wild-type mice, endothelial cells from DMBT1^−/− mice demonstrated reduced migration, proliferation, and tube formation.

In vivo recovery from hindlimb ischemia was attenuated in DMBT1^−/− animals as was vascular endothelial growth factor -induced endothelial sprouting from isolated aortic rings; the latter response could be rescued by the addition of recombinant DMBT1.

The Notch pathway is involved in multiple aspects of vascular development, including arterial-venous differentiation and we found that endothelial cells from DMBT1^−/− mice expressed more EphrinB2 than cells from wild-type mice.

Levels of Dll1, Dll4, Hes1, Hey1, and EphB4, on the other hand, were decreased.

CONCLUSION—

Taken together, the results of this study indicate that DMBT1 functions as an important endothelium-derived ECM protein that is able to bind angiogenic factors and promote adhesion, migration, proliferation, and angiogenesis as well as vascular repair.

Mechanistically, DMBT1 interacts with galectin-3 and modulates the Notch signaling pathway as well as the differential expression of ephrin-B2 and EphB4.

Key Words:

• angiogenesis
• endothelium
• extracellular matrix
• matrix

© 2012 American Heart Association, Inc. 

Arteriosclerosis, Thrombosis, and Vascular Biology. 2012; 32: 442-448

• Hanna Müller,
• Jiong Hu,
• Rüdiger Popp,
• Mirko H.H. Schmidt,
• Karin Müller-Decker,
• Jan Mollenhauer,
• Beate Fisslthaler,
• Johannes A. Eble,
• Ingrid Fleming

+ Author Affiliations

1. From the Institute for Vascular Signalling (H.M., J.H., R.P., B.F., I.F.) and Institute for Vascular Matrix Biology (J.A.E.), Centre for Molecular Medicine and Institute of Neurology (M.H.H.S.), Goethe University, Frankfurt, Germany; Core Facility Tumor Models (K.M.-D.), German Cancer Research Centre, Heidelberg, Germany; Lundbeckfonden Center of Excellence NanoCAN and Molecular Oncology (J.M.), Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark.

Correspondence to Ingrid Fleming, Institute for Vascular Signalling, Centre for Molecular Medicine, Johann Wolfgang Goethe University, Theodor-Stern-Kai 7, D-60590 Frankfurt am Main, Germany. E-mail fleming@em.uni-frankfurt.de