Purification and functional characterization of integrin alpha v beta 5. An adhesion receptor for vitronectin

J Biol Chem. 1990 Jul 5;265(19):11008-13.


We have purified a novel member of the integrin gene family from placenta that serves as a vitronectin receptor. This integrin is composed of the alpha v subunit and a beta subunit that we designate beta 5. Purification was accomplished by immunodepleting a placental extract of integrin alpha v beta 3, allowing us to purify alpha v beta 5 from the remaining extract by monoclonal antibody affinity chromatography on LM 142-Sepharose, which binds to the alpha v subunit. Purification to homogeneity was subsequently achieved by affinity chromatography on wheat germ lectin-Sepharose. Western blot analysis with antibodies raised against alpha v beta 5 and alpha v beta 3 demonstrated that beta 3 and beta 5 were distinct but confirmed that the alpha subunit of the two integrins were immunologically identical. Similarly, antibodies that bind beta 3 proximal to the ligand-binding site failed to react with beta 5, indicating an architectural difference at the ligand-binding site of these related integrins. This structural difference apparently results in a functional distinction, since purified alpha v beta 3 bound to vitronectin, fibrinogen, von Willebrand factor, and fibronectin, whereas integrin alpha v beta 5 bound preferentially to vitronectin. Finally, we demonstrate by three criteria that beta 5 and beta x, the latter of which was identified in lung carcinoma cells (Cheresh, D. A., Smith, J. W., Cooper, H. M., and Quaranta, V. (1989) Cell 57, 59-69), are identical. First, peptide maps of beta x and beta 5 are identical. Secondly, polyclonal antibodies raised against alpha v beta 5 immunoprecipitate both beta 5 and beta x, and finally, the amino-terminal amino acid sequences of beta x and beta 5 are identical.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Antibodies, Monoclonal
  • Blotting, Western
  • Chromatography
  • Chromatography, Affinity
  • Female
  • Glycoproteins / metabolism*
  • Humans
  • Immunosorbent Techniques
  • Integrins / isolation & purification*
  • Integrins / metabolism
  • Molecular Sequence Data
  • Peptide Mapping
  • Placenta / analysis
  • Pregnancy
  • Receptors, Immunologic / metabolism
  • Receptors, Vitronectin
  • Vitronectin


  • Antibodies, Monoclonal
  • Glycoproteins
  • Integrins
  • Receptors, Immunologic
  • Receptors, Vitronectin
  • Vitronectin
  • integrin alphaVbeta5