Figure 1: Constitutive phosphorylation of Axl in NCI-H2347 cells lysed in the presence of phosphatase inhibitors* (phospho lysate) is detected by PathScan ® Phospho-Axl (panTyr) Sandwich ELISA Kit #7042 (top, right). In contrast, a low level of phospho-Axl protein is detected in NCI-H2347 cells lysed in the absence of phosphatase inhibitors* (nonphospho lysate). Similar levels of total Axl protein from both nonphospho or phospho lysates are detected by PathScan ® Total Axl Sandwich ELISA Kit #7040 (top, left). Absorbance at 450 nm is shown in the top figure while corresponding western blots using a phospho-Axl (Tyr814) rabbit antibody (right) or a total Axl (C44G1) Rabbit mAb #4566 (left) are shown in the bottom figure. *Phosphatase inhibitors include sodium pyrophosphate, β-glycerophosphate and Na 3 VO 4 .