Figure 2

Ligation of α2β1 integrin with type I collagen stimulated co-localization with APP. A) THP-1 cells were pre-treated with LPS (25 ng/mL) for 24 hours prior to adhesion to collagen. Cells were plated on tissue culture plastic alone or on type I collagen. Cells were lysed at 30 minutes in 1% Triton X-100 buffer, and either α2 integrin, β1 integrin or APP was immunoprecipitated. Immunoprecipitates were resolved by 7% SDS-PAGE and Western blotted with anti-APP antibody, anti-α1 integrin antibody, anti-α6 integrin antibody, anti-α2 integrin antibody or anti-β1 integrin antibody. B) THP-1 cells were either untreated (c) or treated with LPS (25 ng/mL) for 24 hours. Cells were lysed in RIPA buffer separated by 7% SDS-PAGE and Western blotted using anti-α2 integrin antibody and anti-ERK2 antibody (loading control). C) THP-1 cells were untreated (con) or treated for 24 hours with LPS (1 μg/ml). Cells were plated on coverslips and fixed with 4% paraformaldehyde. Cells were immunostained with and without 1% triton permeabilization with anti-APP antibody. D) THP-1 cells were untreated (c) or treated for 24 hours with LPS (1 μg/ml) or 10 μM Aβ. Cells were lysed in RIPA buffer separated by 7% SDS-PAGE and Western blotted using anti-APP antibody and anti-ERK2 antibody (loading control). Antibody binding was visualized by chemiluminescence.