Semaphorin 3A specifically binds sAPPα.

<p>(A) Wells in a 96-well plate were coated with either 50 ng sAPPα₆₉₅ (APP), 1 µg BSA or 50 ng Semaphorin 3A (Sema3A), blocked with 1% BSA and overlayed with different concentrations of Sema3A or sAPPα₆₉₅ (as indicated below the lanes). After washing, binding was determined by probing with anti-Sema3A antibody. The graph shows concentration-dependent binding of Sema3A to sAPPα₆₉₅ by densitometric quantification of the immunodots using NIH Image J. Bars represent averages of three independent experiments performed in triplicate each. The blot illustrates a representative experiment. (B) Wells in a 96-well plate were coated with 100 ng sAPPα₆₉₅ (APP), blocked with 1% BSA and incubated with increasing volumes of conditioned medium containing alkaline phosphatase-conjugated Semaphorin 3A (Sema3A-AP). After washing, binding was determined by measuring alkaline phosphatase activity. Bars represent averages of three independent experiments performed in triplicate. (C) Streptavidin-coated beads were incubated with biotinylated sAPPα₆₉₅ (bAPP) and Sema3A-AP-conditioned medium or control (non-transfected) medium. After washing, binding was evaluated by measuring alkaline phosphatase activity associated with the beads. Bars represent averages of three independent experiments.