Miniature wireless LED-device for photodynamic-induced cell pyroptosis

Area of Science:

• Biomedical Engineering
• Photochemistry
• Oncology

Background:

• Visible light's limited penetration in tissues restricts phototherapy applications.
• Photosensitizing dyes can generate reactive oxygen species for therapeutic effects.
• Implantable light sources are needed for deep-tissue treatments.

Purpose of the Study:

• To develop a wireless, implantable LED device for deep-tissue photodynamic therapy.
• To evaluate the efficacy of the device in activating photosensitizers and inducing cancer cell death.

Main Methods:

• Fabrication of a 23 mm³ wireless LED device powered by RF energy, emitting 573 nm light.
• Testing wireless power transfer through chicken breast tissue.
• Co-culturing HT-29 human colorectal adenocarcinoma cells with Rose Bengal and activating with the LED device.
• Assessing cell death using Annexin-V FITC and Propidium Iodide staining.

Main Results:

• Effective wireless RF power transfer to the implantable LED at 6 cm through chicken breast.
• Successful activation of Rose Bengal by the LED device.
• Induction of cell death in HT-29 cells, indicated by bubble formation and positive staining for Annexin-V FITC and Propidium Iodide.
• Evidence suggests light-induced pyroptosis as the mode of cell death.

Conclusions:

• A wireless, implantable LED device can effectively deliver light for photodynamic therapy in deep tissues.
• This technology, combined with photosensitizers, can induce cancer cell death.
• Presents a novel approach for future wireless photodynamic immunogenic cell death therapies for deep-seated cancers.