The APAF-1-ALT Colorimetric Cell-Based ELISA Kit provides a lysate-free, convenient, and high-throughput approach for sensitive detection of APAF-1-ALT protein expression profile in cells. The kit can be used for measuring the relative amounts of APAF-1-ALT in cultured cells as well as screening for the effects that various treatments, inhibitors (ie siRNA or chemicals), or activators have on APAF-1-ALT.