title: Integrin receptor specificity for human red cell ICAM-4 ligand. Critical residues for alphaIIbeta3 binding.
abstract: The red cell intercellular adhesion molecule-4 (ICAM-4) binds to different members of the integrin receptor families. To better define the ICAM-4 integrin receptor specificity, cell transfectants individually expressing various integrins were used to demonstrate that alphaLbeta2, alphaMbeta2, and alphaIIbbeta3 (activated) bind specifically and dose dependently to the recombinant ICAM-4-Fc protein. We also show that cell surface ICAM-4 interacts with the cell surface alphaVbeta3 integrin. In addition, using a alpha4beta1 cell transfectant and beta2 integrin-deficient LAD cells, we show here that ICAM-4 failed to interact with alpha4beta1 even after alpha4beta1 activation by phorbol ester or with the monoclonal antibody TS2/16 (+ Mn2+). ICAM-4 amino acids that are critical for alphaIIbbeta3 and alphaVbeta3 interaction were identified by domain deletion analysis, site-directed mutagenesis and synthetic peptide inhibition. Our results provide evidence that the beta3 integrin binding sites encompass the first and second Ig-like domains of ICAM-4. However, while the alphaIIbbeta3 contact site comprises the ABED face of domain D1 with an extension in the C'-E loop of domain D2, the alphaVbeta3 contact site comprises residues on both faces of D1 and in the C'-E loop of D2. These data, together with our previous results, demonstrate that different integrins bind to different but partly overlapping sites on ICAM-4, and that ICAM-4 may accommodate multiple integrin receptors present on leukocytes, platelets and endothelial cells.
authors.affiliation: INSERM U76, Institut National de la Transfusion Sanguine, Paris, France.
authors.forename: Patricia
authors.initials: P
authors.lastname: Hermand
authors.forename: Pierre
authors.initials: P
authors.lastname: Gane
authors.forename: Isabelle
authors.initials: I
authors.lastname: Callebaut
authors.forename: Nelly
authors.initials: N
authors.lastname: Kieffer
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Cartron
authors.forename: Pascal
authors.initials: P
authors.lastname: Bailly
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D016466:CHO Cells; D019556:COS Cells; D015815:Cell Adhesion Molecules / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D002522:Chlorocebus aethiops; D006224:Cricetinae; D003412:Cricetulus; D004912:Erythrocytes / Q000378:metabolism*; D006801:Humans; D016023:Integrins / Q000378:metabolism*; D007739:L Cells; D008024:Ligands; D051379:Mice; D008958:Models, Molecular; D016297:Mutagenesis, Site-Directed; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000378:metabolism; D017384:Sequence Deletion
chemical_list: D015815:Cell Adhesion Molecules; C095100:ICAM4 protein, human; D016023:Integrins; D008024:Ligands; D011994:Recombinant Proteins