ADAM-9 interacts with α_vβ₅ integrin directly. (A) Western blot analysis of ADAM-9 immunoprecipitated with α_vβ₅ integrin. Lane 1, protein marker; lane 2, recombinant ADAM-9 alone; lane 3, α_vβ₅-integrin antibody–conjugated beads, in the absence of recombinant α_vβ₅ integrin, showing only trace amounts of ADAM-9 reactivity; lane 4, ADAM-9 immunoprecipitated with the α_vβ₅-integrin antibody–conjugated beads, in the presence of α_vβ₅ integrin, showing strong staining for ADAM-9. (B) Flow cytometric analysis of hOBs incubated with or without control IgG or anti–α_vβ₅-integrin antibody prior to addition of recombinant ADAM-9. Isotype control antibody is shown in white histograms and ADAM-9 staining in gray histograms. The α_vβ₅-integrin antibody prevented ADAM-9 staining. (C) FIC of hOBs stained for ADAM-9 (green staining) and α_vβ₅ integrin (red staining). Nuclei were counterstained with DAPI. Colocalization of ADAM-9 and α_vβ₅ integrin is shown in the right panel as orange staining. Cells were examined with an objective magnification of × 100 (1.3 NA).