The relationship between lysate protein concentration from untreated and PDGF-treated NIH/3T3 cells and the absorbance at 450 nm using PathScan® Phospho-p44 MAPK (Thr202/Tyr204) Sandwich ELISA Antibody Pair #7278 is shown. NIH/3T3 cells were treated with PDGF for 5 minutes at 37ºC and then lysed.