Photodynamic Therapy

Dear Colleagues,

Dedicating a volume to photodynamic therapy takes on great significance since it means that many steps have been taken to understand that such therapy can take on meaning. In 1903, Von Tappeiner, Director of the Pharmacology Department of the University of Munich, in collaboration with his student, Oscar Raab, demonstrated the therapeutic action of light combined with a photosensitizer and oxygen and coined the term "photodynamic action". Since that time, many studies have experimentally verified the veracity of the effectiveness on different biological structures. In medicine, the use of photodynamic therapy (PDT) is now widely documented and well codified for the treatment of oncological and non-oncological diseases such as macular degeneration of the retina and carcinoma of the esophagus and lung. In dermatology, the use varies from oncological diseases such as basal cell carcinoma, squamous cell carcinoma, actinic and non-oncological keratoses, bacterial, fungal, viral, immunological or inflammatory infections in the treatment of chronic wounds, and, finally, in cosmetology for the photo rejuvenation. PDT is based on the cytotoxic action of some hyperactive oxygen species, especially singlet oxygen but also superoxide anion and hydroxyl radicals, generated by the transfer of energy and/or electrons from the photoexcited oxygen sensitizer. Three important mechanisms are responsible for the efficacy of PDT: (1) direct death of tumor cells or inflammation, (2) damage to tumor vessels, (3) immunological response associated with the stimulation of leukocytes and the release of interleukins and other cytokines, growth factors, complement components, acute phase proteins and other immunoregulators. This topic aims to cover all aspects of photodynamic therapy including the discovery of new natural and synthetic photosensitizers, biomaterials and nanotechnology, in vitro and in vivo studies and clinical trials. With the collaboration of all of us, this volume will strengthen and stimulate further research!

Dr. Stefano Bacci
Prof. Dr. Kyungsu Kang
Topic Editors