A rapid, quantitative and inexpensive method for detecting apoptosis by flow cytometry in transiently transfected cells

We describe a rapid and quantitative flow cytometric method for determining the apoptotic or anti-apoptotic potential of a gene in various cell types. A plasmid carrying green fluorescent protein (GFP) is co-transfected with an expression vector encoding the gene of interest. Subsequently cells are stained with propidium iodide and, utilising flow cytometry, transfected, GFP-expressing single cells are detected and apoptotic cells in this population are identified by their DNA content of <2 N. The method detects apoptosis as reliably as established methods using in situ nick-end labelling but is faster, easier and less expensive.