Yu Zhou, Liu Shiqiang, Cui Jiangbo, Song Yajuan, Wang Tong, Song Baoqiang, Peng Pai, Ma Xianjie
Department of Plastic Surgery, Xijing Hospital; Air Force Medical University, Xi'an, Shaanxi Province, China.
Ultrastruct Pathol. 2020 Jan 2;44(1):141-152. doi: 10.1080/01913123.2020.1720876. Epub 2020 Jan 28.
Tissue expansion has been widely used for plastic, reconstructive, and esthetic surgeries. A mouse scalp expansion model can effectively mimic the characteristics of human skin expansion. However, a detailed study of the histological features and ultrastructural characteristics of expanded scalp is lacking, especially early ultrastructural changes. Here, a mouse scalp expansion model was established and the expanded scalp samples were obtained on day 2 (group I) and 4 (group II) post final injection. Histological analysis revealed epidermal thickening, dermal thinning, subcutaneous fat thinning, and capsule formation in the expanded samples. Ultrastructural evaluation showed the presence of keratinocytes with numerous tonofibrils and damaged mitochondria, and several ruptured collagen fibers and increased number of active fibroblasts and myofibroblasts were observed in the dermis and capsules. Adipocyte dedifferentiation was detected in the expanded samples of both groups, but formation of autophagosomes was only detected in the dermal fibroblasts of group I. Thus, early changes in expanded tissue should be carefully monitored, as it may help avoid dermal thinning and promote expanded tissue regeneration.
组织扩张术已广泛应用于整形、重建和美容手术。小鼠头皮扩张模型能够有效模拟人类皮肤扩张的特征。然而，目前缺乏对扩张头皮的组织学特征和超微结构特征的详细研究，尤其是早期超微结构变化。在此，建立了小鼠头皮扩张模型，并在末次注射后第2天（I组）和第4天（II组）获取扩张头皮样本。组织学分析显示，扩张样本中存在表皮增厚、真皮变薄、皮下脂肪变薄以及包膜形成。超微结构评估显示，角质形成细胞含有大量张力原纤维且线粒体受损，在真皮和包膜中观察到数条断裂的胶原纤维以及活跃的成纤维细胞和肌成纤维细胞数量增加。在两组的扩张样本中均检测到脂肪细胞去分化，但仅在I组的真皮成纤维细胞中检测到自噬体的形成。因此，应仔细监测扩张组织的早期变化，因为这可能有助于避免真皮变薄并促进扩张组织再生。
