Figure 5.

Binding of PS1 by immobilized anti-PS1 antibody results in capture of γ-secretase activity. Solubilized γ-secretase was subject to immunoprecipitation (IP) using normal IgG or anti-PS1-NTF IgG. (A) Western blotting analysis using anti-PS1-NTF and anti-PS1-CTF antibodies was performed with the immunoprecipitates. The bands corresponding to PS1-NTF and PS1-CTF are labeled. (B) The resuspended pellets from the normal IgG and anti-PS1 immunoprecipitation steps were evaluated with the in vitro γ-secretase assay (assaying for M-Aβ40 and M-Aβ42). The results are reported as ECL signals (mean of two independent assay determinations).