Collagen stimulates a selective increase in Aβ1-40 that is dependent on Src tyrosine kinase activity. THP-1 cells were either untreated or treated for 30 min with SB202190 (100 nM), PP2 (5 μM), γ-secretase inhibitor (10 μM), β-secretase inhibitor (5 μM) or DMSO vehicle. Cells were plated on tissue culture plastic or collagen for 48 hours. Media was then collected and analyzed by human Aβ1-40 and Aβ1-42 ELISA. Data were analyzed by unpaired ANOVA with Tukey's post-test comparison and are expressed as mean +/- SD (* = p < 0.001 from control, ** = p < 0.001 from collagen). SB202190 and PP2 treated collagen conditions were normalized to percent decrease due to drug only. Values are representative of three independent experiments.