Figure 1

Representative hybridoma screening results. Hybridoma supernatants were compared by ELISA for binding to murine α5β1-Fc heterodimer, α5-Fc or β1-Fc homodimer or an irrelevant Fc fusion protein, (A). Hybridomas were found to produce antibodies with specific preferences for each protein. Supernatants were further tested for binding to murine EC's by flow cytometry, (B). The majority of antibodies tested recognized cell surface integrin. Antibodies purified from supernatants that recognized murine EC's by flow cytometry and showed a preference for α5β1 heterodimer were compared for their capacity to inhibit the binding of α5β1-Fc to mouse fibronectin by competitive ELISA, (C). Many antibodies inhibited integrin-fibronectin binding; one antibody, 321.1, was found to promote binding. Antibodies were assessed for binding to cellular integrin α5β1 on SVR cells by flow cytometry, (D). Most of the antibodies that bound integrin α5β1 by ELISA also bind cell surface integrin in vitro.