Figure 1: Constitutive phosphorylation of NPM-ALK in Karpas299 cells lysed in the presence of phosphatase inhibitors (phospho-lysate) can be detected by PathScan ® Phospho-ALK (Tyr1604) Sandwich ELISA Kit #7324. In contrast, only a low level of phospho-NPM-ALK protein is detected in Karpas299 cells lysed without addition of phosphatase inhibitors to the lysis buffer (nonphospho-lysate). However, similar levels of total NPM-ALK protein from either nonphospho or phospho-lysates can be detected by PathScan ® Total ALK Sandwich ELISA Kit #7322. Absorbance at 450 nm is shown in the top figure, while the corresponding Western blots using Phospho-ALK (Tyr1604) Antibody #3341 (right panel) or a total ALK Rabbit mAb #3333 (left panel), are shown in the bottom figure.