Scripps VIVO scripps research logo

  • Index
  • Log in
  • Home
  • People
  • Organizations
  • Research
  • Events
Search form

Mechanisms and consequences of affinity modulation of integrin alpha(v)beta(3) detected with a novel patch-engineered monovalent ligand

Academic Article
uri icon
  • Overview
  • Identity
  • Additional Document Info
  • View All
scroll to property group menus

Overview

authors

  • Pampori, N.
  • Hato, T.
  • Stupack, D. G.
  • Aidoudi, S.
  • Cheresh, D. A.
  • Nemerow, Glen
  • Shattil, S. J.

publication date

  • July 1999

journal

  • Journal of Biological Chemistry  Journal

abstract

  • Integrin alpha(V)beta(3) mediates diverse responses in vascular cells, ranging from cell adhesion, migration, and proliferation to uptake of adenoviruses. However, the extent to which alpha(V)beta(3) is regulated by changes in receptor conformation (affinity), receptor diffusion/clustering (avidity), or post-receptor events is unknown. Affinity regulation of the related integrin, alpha(IIb)beta(3), has been established using a monovalent ligand-mimetic antibody, PAC1 Fab. To determine the role of affinity modulation of alpha(V)beta(3), a novel monovalent ligand-mimetic antibody (WOW-1) was created by replacing the heavy chain hypervariable region 3 of PAC1 Fab with a single alpha(V) integrin-binding domain from multivalent adenovirus penton base. Both WOW-1 Fab and penton base bound selectively to activated alpha(V)beta(3), but not to alpha(IIb)beta(3), in receptor and cell binding assays. alpha(V)beta(3) affinity varied with the cell type. Unstimulated B-lymphoblastoid cells bound WOW-1 Fab poorly (apparent K(d) = 2.4 microM), but acute stimulation with phorbol 12-myristate 13-acetate increased receptor affinity >30-fold (K(d) = 80 nM), with no change in receptor number. In contrast, alpha(V)beta(3) in melanoma cells was constitutively active, but ligand binding could be suppressed by overexpression of beta(3) cytoplasmic tails. Up-regulation of alpha(V)beta(3) affinity had functional consequences in that it increased cell adhesion and spreading and promoted adenovirus-mediated gene transfer. These studies establish that alpha(V)beta(3) is subject to rapid regulated changes in affinity that influence the biological functions of this integrin.

subject areas

  • Adenoviridae
  • Animals
  • Antibody Affinity
  • B-Lymphocytes
  • CHO Cells
  • Cell Line
  • Cloning, Molecular
  • Cricetinae
  • Drosophila melanogaster
  • Fibrinogen
  • Genetic Vectors
  • Humans
  • Immunoglobulin Fab Fragments
  • Kinetics
  • Ligands
  • Polymerase Chain Reaction
  • Receptors, Vitronectin
  • Recombinant Proteins
  • Tetradecanoylphorbol Acetate
  • Transfection
  • Up-Regulation
scroll to property group menus

Identity

International Standard Serial Number (ISSN)

  • 0021-9258

Digital Object Identifier (DOI)

  • 10.1074/jbc.274.31.21609

PubMed ID

  • 10419468
scroll to property group menus

Additional Document Info

start page

  • 21609

end page

  • 21616

volume

  • 274

issue

  • 31

©2021 The Scripps Research Institute | Terms of Use | Powered by VIVO

  • About
  • Contact Us
  • Support