Adhesion of CHO cells stably expressing normal or mutant α_IIbβ₃ or α_vβ₃ complexes to solid-phase fibrinogen or vitronectin. Approximately 4 × 10⁵ cells were added to the wells of microtiter plates coated with ligands and incubated at 37°C.Adhesion was examined by phase-contrast microscopy as described in “Materials and methods.” (A) CHO-α_IIbβ₃ or CHO-α_IIbβ₃(616-690del) cells were seeded onto plates coated with 10 μg/mL fibrinogen and incubated for 10 minutes. (B-C) CHO-α_vβ₃ and CHO-α_vβ₃(616-690del) cells were seeded onto microtiter plates coated with 10 μg/mL vitronectin (B) or 10 μg/mL fibrinogen (C) and incubated for 30 minutes. Original magnification, × 100.