Establishment and Identification of a Deep Second-Degree Frostbite Model in Mouse Skin

The aim of this study is to address the limited research on skin frostbite models and the gaps in pathological identification of time-series injuries in frostbitten skin, which hinder comprehensive assessment of injury severity. A deep second-degree frostbite model was developed in BALB/c nude mice, and staining identification was performed at various stages, from the onset of frostbite to the healing process. Continuous observations at multiple time points provided a more accurate and comprehensive standard for comparison in frostbite treatment experiments. A deep second-degree frostbite model was developed using BALB/c nude mice. Histopathological examination was performed with hematoxylin-eosin (HE) staining, while Masson's Trichrome (MT) staining was used to observe collagen recovery. Additionally, immunofluorescence staining was conducted to analyze epidermal cells and dermal structures. A deep second-degree frostbite model was successfully developed in BALB/c nude mice. Histopathological characteristics of mouse skin tissue were examined through HE staining at various time points. MT staining highlighted changes in the morphology and thickness of the original fibers. Immunofluorescence staining offered a detailed evaluation of the damage and recovery of appendages, including hair follicles and sweat glands. The deep second-degree frostbite model in BALB/c nude mice establishes a standard for studying skin frostbite injuries and developing related treatments.