A novel murine tail model for radiation-induced skin injury following localized irradiation at varying doses

BackgroundRadiation therapy is one cornerstone of oncologic treatment. Radiation-induced skin injury (RISI) is a dose-limiting complication of radiotherapy. RISI is also common in victims of accidental exposure, which often aggravates the patients condition and becomes a difficult medical issue. However, the damage mechanisms of RISI remain unclear, and the prevention and treatment measures are limited. An appropriate animal model holds great significance for addressing these issues. MethodsC57BL/6 mice were employed to establish RISI model by irradiating 2 cm section of the mouse tail with 20Gy, 30Gy, and 40Gy of single irradiation. Skin injuries were scored with a modified semi-quantitative scale. H&E staining, IHC for dopachrome tautomerase (DTC) and Masson staining were used for histopathological evaluations of RISI. ResultsWe innovatively established animal models of RISI through tail irradiation. The model mice showed typical symptoms of dry desquamation, moist desquamation, ulcers and necrosis in the irradiated area, which were highly similar to the clinical manifestations. Concurrently, we discovered that in the later stage of this model, the interstitial tissue at irradiated site presented a fibrotic phenotype with good dose dependence. It should be noted that tail irradiation causes dynamic changes in skin melanin, with early excessive deposition and late loss, which renders the observation of radiation-induced skin erythema difficult. For this reason, we specifically revised the scoring criteria for RISI. ConclusionIn conclusion, this study established an easily operable and highly reproducible tail irradiation model, providing a novel platform for in-depth research on the mechanisms and translational applications of RISI.