Holographic Study of the Response of HeLa Cells to Photodynamic Treatment with Endogenously Generated Protoporphyrin IX

Changes in morphological and optical parameters of HeLa cells preincubated with 5-aminolevulinic acid (5-ALA), after photodynamic treatment (PDTr) with different intensity of excitation radiation are studied by digital holographic microscopy. Optimization of the algorithm of cell segmentation on their phase image is performed. The developed algorithm allows for automatic data acquisition on extended amounts of cells in a sample (over 600). The morphological and optical parameters of cells at different doses of PDTr were determined, and the lognormal distribution of average phase shift of the cells was demonstrated. Changes in the cell parameters at different radiation doses which initiate programmed cell death and necrosis were recorded.