Figure 1. Constitutive phosphorylation of FGFR2 in KATO III cells lysed in the presence of phosphatase inhibitors* (phospho lysate) is detected by PathScan ® Phospho-FGFR2 (panTyr) Sandwich ELISA Kit #7954 (upper, right). In contrast, a low level of phospho-FGFR2 protein is detected in KATO III cells lysed in the absence of phosphatase inhibitors (nonphospho lysate). Similar levels of total FGFR2 protein from both nonphospho and phospho lysates are detected by PathScan ® Total FGFR2 Sandwich ELISA Kit #7939 (upper, left). Absorbance at 450 nm is shown in the top figure while corresponding western blots using Phospho-FGF Receptor (Tyr653/654) Antibody #3471 (right) or a total FGFR2 Rabbit mAb (left) are shown in the bottom figure. *Phosphatase inhibitors include sodium pyrophosphate, β-glycerophosphate, and Na 3 VO 4 .
Figure 2. The relationship between protein concentration of phospho or nonphospho lysates and the absorbance at 450 nm is shown. KATO III cells were cultured (85% confluence) and lysed with or without the addition of phosphatase inhibitor to the lysis buffer (phospho or nonphospho lysate, respectively).