Photodynamic therapy as a new treatment modality for inflammatory and infectious conditions

Abstract

Photodynamic therapy (PDT) is currently used as a minimally invasive therapeutic modality for cancer. Whereas antitumor treatment regimens require lethal doses of photosensitizer and light, sublethal doses may have immunomodulatory effects, antibacterial action and/or regenerative properties. A growing body of evidence now indicates that non-lethal PDT doses can alleviate inflammation or treat established soft-tissue infections in various murine models of arthritis, experimental encephalomyelitis, inflammatory bowel disease and chronic skin ulcers. Furthermore, PDT is already used in clinical application and clinical trial for the treatment of psoriasis, chronic wounds and periodontitis in humans. Sublethal PDT should be regarded as a new viable option for the treatment of inflammatory conditions.

The Combination of Antimicrobial Photodynamic Therapy and Photobiomodulation Therapy for the Treatment of Palatal Ulcers: A Case Report

“…The use of aPDT is well documented for many diseases and conditions such as infected leg ulcers, 20 diabetic foot, 21 and chronic skin ulcers. 22 With specific regard to the oral environment, its action includes the treatment of leukoplakia, 17 lichen planus, 23 periodontal pockets, 24 peri-implantitis, 25 and oral decontamination as well. 26,27 In the specific case of palatal ulcers during orthodontic therapy, this is the first case report to use this approach to solve this type of injury.…”

Porphyrin-based cationic amphiphilic photosensitisers as potential anticancer, antimicrobial and immunosuppressive agents

“…Therefore, in psoriasis, as well as in various other chronic inflammatory diseases, PDT exerts direct immunosuppressive effects (reviewed in Mroz and Hamblin 2011;Reinhard et al 2015). It must be emphasized that a recent meta-analysis on psoriasis showed lower efficiency of ALA-PDT compared to the classical phototherapy (Almutawa et al 2015).…”

Sub-lethal doses of photodynamic therapy affect biofilm formation ability and metabolic activity of Enterococcus faecalis

“…PDT is mediated through the exposure of photosensitizers (PSs) with light at a specific wavelength to produce reactive oxygen species (ROS) that can directly damage sub-cellular components [8]. The successful outcome of PDT depends on the type and concentration of PS, exposure time of the microorganisms with PS, and dose of light irradiation [12].…”