Indocyanine green based photodynamic therapy for keloids: Fundamental investigation and clinical improvement

Background: Keloid, a prevalent pathological skin lesion, presents significant challenges in terms of treatment efficacy. Photodynamic therapy (PDT), an increasingly popular adjuvant treatment, has shown significant potential in the management of various disorders, including cancer. However, the therapeutic potential of indocyanine green-mediated photodynamic therapy (ICG-PDT) for keloids has not yet been demonstrated.Methods: In this study, we divided the experimental groups into control group, Photothermal Therapy group, Photodynamic Therapy group, and Combined Therapy group. The in vitro investigation aimed to optimize the clinical application of PDT for keloid treatment by elucidating its underlying mechanism. Subsequently, on this basis, we endeavored to manage a clinical case of keloid by employing surgical intervention in conjunction with modified ICG-PDT.Results: Our investigation revealed an unexpected outcome that ICG-PDT maximally inhibited the cellular activity and migration of keloid fibroblasts only when photodynamic mechanism took effect. Additionally, the induction of autophagy and apoptosis, as well as the inhibition of collagen synthesis, were particularly evident in this experimental group. Furthermore, the above therapeutic effect could be achieved at remarkably low drug concentrations. Building upon the aforementioned experimental findings, we successfully optimized the treatment modality for the latest case and obtained a more favorable treatment outcome.Conclusions: This study investigated the mechanism of ICG-PDT treatment and optimized the in vivo treatment regimen, demonstrating the significant therapeutic potential of ICG-PDT treatment in clinical keloid treatment.