Binding of FGF-1, -2, -4, -5, -6, -7, -9, and -10 to α₂M and α₂M*.

FGFs were labeled with ¹²⁵I, as described in “Materials and methods,” and incubated with 0.5 mg/mL α₂M (A) or α₂M* (B) for 2 hours at 37°C followed by nondenaturing pore-limit electrophoresis. Radioactivity associated with the α₂M band was quantified on the Phosphorimager and compared with the radioactivity of the appropriate ¹²⁵I-FGF alone, which was defined as 100%, to determine the percentage of each FGF that bound to α₂M. Each bar represents the mean of at least 2 independent determinations ± SD, except for FGF-10, where n = 1.