Profile of myelin basic protein kinase activation during constitutive eosinophil and neutrophil apoptosis.

Constitutive eosinophil and neutrophil apoptosis was induced by incubation in the absence of survival-promoting cytokines. At the indicated times, the cells were lysed by the addition of ice-cold immunoprecipitaton buffer, and soluble fractions were prepared and subjected to electrophoresis on 10% SDS-PAGE. Protein kinase activities were assayed using an “in gel” renaturation kinase assay employing MBP as the substrate. A representative autoradiograph obtained from 3 independent experiments is shown.