A Designed Angiopoietin-1 Variant, Dimeric CMP-Ang1 Activates Tie2 and Stimulates Angiogenesis and Vascular Stabilization in N-glycan Dependent Manner

Sci Rep. 2015 Oct 19:5:15291. doi: 10.1038/srep15291.

Abstract

Angiopoietin-1 (Ang1), a potential growth factor for therapeutic angiogenesis and vascular stabilization, is known to specifically cluster and activate Tie2 in high oligomeric forms, which is a unique and essential process in this ligand-receptor interaction. However, highly oligomeric native Ang1 and Ang1 variants are difficult to produce, purify, and store in a stable and active form. To overcome these limitations, we developed a simple and active dimeric CMP-Ang1 by replacing the N-terminal of native Ang1 with the coiled-coil domain of cartilage matrix protein (CMP) bearing mutations in its cysteine residues. This dimeric CMP-Ang1 effectively increased the migration, survival, and tube formation of endothelial cells via Tie2 activation. Furthermore, dimeric CMP-Ang1 induced angiogenesis and suppressed vascular leakage in vivo. Despite its dimeric structure, the potencies of such Tie2-activation-induced effects were comparable to those of a previously engineered protein, COMP-Ang1. We also revealed that these effects of dimeric CMP-Ang1 were affected by specified N-glycosylation in its fibrinogen-like domain. Taken together, our results indicate that dimeric CMP-Ang1 is capable of activating Tie2 and stimulating angiogenesis in N-glycan dependent manner.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Angiopoietin-1* / genetics
  • Animals
  • Capillary Permeability / drug effects
  • Cell Line
  • Endothelial Cells / drug effects
  • Endothelial Cells / metabolism
  • Glycosylation
  • Humans
  • Matrilin Proteins* / genetics
  • Mice
  • Models, Molecular
  • Neovascularization, Physiologic / drug effects*
  • Polysaccharides / metabolism*
  • Protein Conformation
  • Protein Multimerization
  • Proto-Oncogene Proteins c-akt / metabolism
  • Receptor, TIE-2 / agonists*
  • Receptor, TIE-2 / metabolism
  • Recombinant Fusion Proteins / chemistry
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Recombinant Fusion Proteins / pharmacology*
  • Signal Transduction / drug effects

Substances

  • Angiopoietin-1
  • Matrilin Proteins
  • Polysaccharides
  • Recombinant Fusion Proteins
  • Receptor, TIE-2
  • Proto-Oncogene Proteins c-akt