A431 cell lysates were immunoprecipitated overnight with a monoclonal antibody against p53. The resulting immunoprecipitates were separated by SDS-PAGE. Lane 1: Negative IP control; Lane 2: Test sample ; Lane 3: A431 cell lysate positive control. Western blotting was performed using the same p53 monoclonal antibody and incubated with IRDye 680RD Immunoprecipitation Detection Reagent.