The p38 MAPK Colorimetric Cell-Based ELISA Kit provides a lysate-free, convenient, and high-throughput approach for sensitive detection of p38MAPK protein expression profile in cells. The kit can be used for measuring the relative amounts of p38MAPK in cultured cells as well as screening for the effects that various treatments, inhibitors (ie siRNA or chemicals), or activators have on p38MAPK.