Exploiting STED microscopy to unveil cellular damage induced by photosensitizing molecules

Abstract

This one-year SPRINT project is focused in a research area that is emerging rapidly and expanding the limits to resolve cell structures and their functions; stimulated emission depletion (STED) microscopy of living cells tagged to photodynamic therapy. By bridging the groups from Lund University (SE) and UNESP (Brazil) we aim to approach the underlying mechanisms of cell-photosensitizer (PS) interaction in photodynamic therapy (PDT) of cancer cells using super-resolution microscopy, with potential expansion to other areas. PDT is minimally invasive procedure that induces cell death by photooxidative reactions. Simplified models of tumor cells have already been photosensitized in the ongoing project of the Brazilian group, however, the precise cellular localization of the PS in cancer cells remains unknown. The present project will tackle this issue using the super-resolution STED microscope available at Lund University. With the aid of the STED microscope, we shall determine the precise end point (organelles) of the PS after cellular uptake, which will generate knowledge to further impact the pathway of cellular death triggered by illumination. In a series of meeting between the two groups, we have already identified possible experimental setups, materials and cell lines that would be well suited to perform this initial yet attractive project. This mobility project grant will catalyze and expand considerably the interactions between researchers at Lund University and UNESP, developing further our collaboration, and solidifying a foundation for more extensive research partnership. (AU)