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Updated: Jun 12, 2026

An In-House-Built and Light-Emitting-Diode-Based Photodynamic Therapy Device for Enhancing Verteporfin Cytotoxicity in a 2D Cell Culture Model
Published on: January 13, 2023
Photodynamic therapy and cell death pathways
David Kessel1, Nancy L Oleinick
1Wayne State University School of Medicine, Detroit, MI, USA.
Abstract:
Photodynamic therapy (PDT) is the term used to describe the irradiation of photosensitized cells or tissue with phototoxic consequences. This process can result in the rapid initiation of not only apoptosis, an irreversible death pathway, but also autophagy. The procedures described here are designed to characterize the correlation between the PDT dose vs. survival of cells in vitro, the apoptotic effects of photodamage, and the extent of an autophagic response. These are assessed by clonogenic assays, observation of condensed chromatin characteristic of apoptosis, activation of "executioner" caspases, and the autophagic flux as indicated by comparing accumulation of the LC3-II protein under conditions where processing of autophagosomes is retarded vs. is not retarded.
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