Image-Based Quantification of Cell Debris as a Measure of Apoptosis

Apoptosis is a controlled
form of cell death that can be induced
by various diseases and exogenous toxicants. Common apoptosis-detection
methods rely on fluorescent markers, which necessitate the use of
costly reagents and time-consuming labeling procedures. Label-free
methods avoid these problems, but often require specialized instruments
instead. Here, we utilize apoptotic-cell disintegration to develop
a novel label-free detection method based on the quantification of
subcellular debris particles in bright-field-microscopy images. Debris
counts show strong correlations with fluorescence-based annexin V
staining and can be used to study concentration-dependent and temporal
apoptosis activation. The method is rapid, low-cost, and easy to apply,
as the only experimental step comprises bright-field imaging of culture-media
samples followed by automated image processing. The late-stage nature
of the debris measurement means that the method can complement other,
established apoptosis assays, and its accessibility will allow a wider
community of researchers to study apoptotic cell death.