Automatic image analysis of multicellular apoptosis process

Apoptotic programmed cell death (PCD) is a common and fundamental aspect of developmental maturation. Image processing techniques have been developed to detect apoptosis at the single-cell level in a single still image, while an efficient algorithm to automatically analyze the temporal progression of apoptosis in a large population of cells is unavailable. In this work, we have developed an ImageJ-based program that can quantitatively analyze time-lapse microscopy movies of live tissues undergoing apoptosis with a fluorescent cellular marker, and subsequently extract the temporospatial pattern of multicellular response. The protocol is applied to characterize apoptosis of Drosophila wing epithelium cells at eclosion. Using natural anatomic structures as reference, we identify dynamic patterns in the progression of apoptosis within the wing tissue, which not only confirms the previously observed collective cell behavior from a quantitative perspective for the first time, but also reveals a plausible role played by the anatomic structures in Drosophila apoptosis.