Centre LOEX de l'Université Laval, Génie Tissulaire et Régénération: LOEX du Centre de Recherche FRSQ du Centre Hospitalier affilié Universitaire de Québec, Département de Chirurgie, Faculté de Médecine, Université Laval, Québec, QC, Canada.
Burns. 2012 May;38(3):421-7. doi: 10.1016/j.burns.2011.09.001. Epub 2011 Oct 29.
Hypertrophic scars are a pathological process characterized by an excessive deposition of extracellular matrix components. Using a tissue-engineered reconstructed human skin (RHS) method, we previously reported that pathological keratinocytes induce formation of a fibrotic dermal matrix. We further investigated keratinocyte action using conditioned media. Results showed that conditioned media induce a similar action on dermal thickness similar to when an epidermis is present. Using a two-dimensional electrophoresis technique, we then compared conditioned media from normal or hypertrophic scar keratinocytes and determined that TIMP-1 was increased in conditioned media from hypertrophic scar keratinocytes. This differential profile was confirmed using ELISA, assaying TIMP-1 presence on media from monolayer cultured keratinocytes and from RHS. The dermal matrix of these RHS was recreated using mesenchymal cells from three different origins (skin, wound and hypertrophic scar). The effect of increased TIMP-1 levels on dermal fibrosis was also validated independently from the mesenchymal cell origin. Immunodetection of TIMP-1 showed that this protein was increased in the epidermis of hypertrophic scar biopsies. The findings of this study represent an important advance in understanding the role of keratinocytes as a direct potent modulator for matrix degradation and scar tissue remodeling, possibly through inactivation of MMPs.
增生性瘢痕是一种以细胞外基质成分过度沉积为特征的病理过程。我们先前使用组织工程化的重建人皮肤 (RHS) 方法报告说，病理性角质形成细胞诱导纤维性真皮基质的形成。我们使用条件培养基进一步研究了角质形成细胞的作用。结果表明，条件培养基对真皮厚度的诱导作用与存在表皮时相似。然后，我们使用二维电泳技术比较了正常或增生性瘢痕角质形成细胞的条件培养基，并确定 TIMP-1 在增生性瘢痕角质形成细胞的条件培养基中增加。使用 ELISA 进一步证实了这种差异图谱，检测了单层培养的角质形成细胞和 RHS 培养基中 TIMP-1 的存在。使用来自三种不同来源（皮肤、伤口和增生性瘢痕）的间充质细胞重新创建了这些 RHS 的真皮基质。还独立于间充质细胞来源验证了增加的 TIMP-1 水平对真皮纤维化的影响。TIMP-1 的免疫检测显示，这种蛋白在增生性瘢痕活检的表皮中增加。这项研究的结果代表了对角质形成细胞作为基质降解和瘢痕组织重塑的直接有效调节剂的作用的重要认识，可能是通过 MMPs 的失活。
