  Changes in morphological characteristics of cells from two cultured cancer
cell lines, HeLa and A549, induced by photodynamic treatment with Radachlorin
photosensitizer have been monitored using digital holographic microscopy. The
observed dose-dependent post-treatment dynamics of phase shift variations
demonstrated several scenarios of cell death. In particular the phase shift
increase at low doses can be associated with apoptosis while its decrease at
high doses can be associated with necrosis. Two cell types were shown to be
differently responsive to treatment at the same doses. Although the sequence of
death scenarios with increasing irradiation dose was demonstrated to be the
same, each specific scenario was realized at substantially different doses.
Results obtained by holographic microscopy were confirmed by confocal
fluorescence microscopy with the commonly used test assay.
