QUALITATIVE AND QUANTITATIVE-ANALYSIS OF DNA FRAGMENTATION USING DIGITAL IMAGING

Apoptosis is an important and common pathway of cellular death. Differ entiation from cellular necrosis and quantitation of apoptosis within the milieu of necrosis are analytical challenges. We describe the use of the RIT120 digital imaging software package for quantitative and qu alitative analysis of apoptotic DNA ladders induced by a variety of ag ents, such as serum, tumor necrosis factor-alpha, transforming growth factor-beta 1, and nitric oxide, Autoradiographs of DNA ladders are de nsitometrically scanned to yield a set of curves with peaks correspond ing to specific DNA fragments, thereby allowing quantitative subtracti on of concurrent DNA degradation from necrotic death. Integration of t he areas specifically under the peaks yields a quantitative measure of apoptosis. We provide a useful, rapid, and objective means to quantit ate apoptosis, using relatively inexpensive hardware and software. (C) 1997 Academic Press.