Lee Dongyoun, Abudureyimu Gulimila, Park Ji-Hye, Jang Kee-Taek, Kwon Ghee Young, Shim Jong Sup
Department of Dermatology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Ann Dermatol. 2021 Apr;33(2):108-115. doi: 10.5021/ad.2021.33.2.108. Epub 2021 Mar 8.
We recently discovered the presence of specialized nail mesenchyme below the nail matrix and designated it as onychomatricodermis.
We did further research to characterize the histologic, histochemical, immunohistochemical and ultrastructural features of the onychomatricodermis containing onychofibroblasts in the nail unit.
Ten polydactyly nail unit specimens and 8 nail matrix biopsies were included. H&E-stained slides were reviewed. We did Alcian blue staining and Masson Trichrome staining, as well as immunohistochemical staining for type I collagen, CD10, CD13 and CD34. In addition, polydactyly nail units were examined by transmission electron microscopy.
In H&E staining, the specialized mesenchyme called onychomatricodermis was observed to be slightly distant from the undersurface of the nail matrix and be less eosinophilic area. Onychomatricodermal onychofibroblasts showed light purple abundant cytoplasm. Masson Trichrome staining revealed fewer collagen fibers within the onychomatricodermis. In Alcian blue staining the onychomatricodermis showed mucin deposition within the onychofibroblasts and around them. Immunohistochemically, type I collagen was expressed much less in the onychomatricodermis while it was strongly expressed elsewhere in the nail unit. In nail matrix biopsy specimens onychomatricodermal onychofibroblasts expressed CD10 and CD13 strongly, and expressed CD34 as well. Ultrastructurally, collagen fibrils were found sparsely within the onychomatricodermis, whereas collagen fibrils were densely distributed in the dermis of other parts of the nail unit.
We demonstrated that there was less collagen expression in the onychomatricodermis containing onychofibroblasts. In addition, we found morphological and immunohistochemical features of onychomatricodermal onychofibroblasts (onychofibroblasts of Dongyoun). These findings support the presence of onychomatricodermis containing onychofibroblasts in the nail unit.
我们最近在甲母质下方发现了特殊的甲间充质，并将其命名为甲床真皮。
我们进一步研究以表征甲单位中含有甲成纤维细胞的甲床真皮的组织学、组织化学、免疫组织化学和超微结构特征。
纳入10个多指甲单位标本和8个甲母质活检标本。对苏木精-伊红染色切片进行评估。我们进行了阿尔辛蓝染色和马松三色染色，以及I型胶原、CD10、CD13和CD34的免疫组织化学染色。此外，对多指甲单位进行透射电子显微镜检查。
在苏木精-伊红染色中，观察到称为甲床真皮的特殊间充质与甲母质下表面略有距离，且嗜酸性区域较少。甲床真皮甲成纤维细胞显示出淡紫色的丰富细胞质。马松三色染色显示甲床真皮内胶原纤维较少。在阿尔辛蓝染色中，甲床真皮在甲成纤维细胞内及其周围显示粘蛋白沉积。免疫组织化学方面，I型胶原在甲床真皮中的表达远低于甲单位其他部位。在甲母质活检标本中，甲床真皮甲成纤维细胞强烈表达CD10和CD13，也表达CD34。超微结构上，甲床真皮内胶原原纤维稀疏，而甲单位其他部位的真皮中胶原原纤维密集分布。
我们证明含有甲成纤维细胞的甲床真皮中胶原表达较少。此外，我们发现了甲床真皮甲成纤维细胞（董允甲成纤维细胞）的形态学和免疫组织化学特征。这些发现支持甲单位中存在含有甲成纤维细胞的甲床真皮。
