Lacroix M, Bovy T, Nusgens B V, Lapière C M
Laboratory of Experimental Dermatology, CHU Sart-Tilman, Liège, Belgium.
Arch Dermatol Res. 1995;287(7):659-64. doi: 10.1007/BF00371739.
In this study we investigated the influence of keratinocytes on the phenotype of fibroblasts in an in vitro human skin equivalent. Keratinocytes were seeded at the surface of fibroblast-populated mechanically restrained type I collagen gels (lattices). Lattices without keratinocytes were handled in parallel as controls. After 2 and 4 days in culture, the keratinocyte layer was removed and the steady-state level of the mRNA for the main extracellular matrix macromolecules and interstitial collagenase produced by the fibroblasts was measured by Northern and dot blot analysis. A 50% decrease in the amount of procollagen type I and type III mRNAs was observed after 2 and 4 days of coculture while collagenase gene expression was upregulated by 300% when compared with control lattices. No significant modulation of type IV and type VI collagen, elastin or laminin B1 mRNA levels was found. Fibronectin mRNA levels in fibroblasts were significantly increased only on day 4. All the observed changes could be reproduced using a conditioned medium collected from a lattice covered with keratinocytes added to a lattice containing fibroblasts alone. These results indicate that in an in vitro reconstituted skin, keratinocytes are able to modulate the biosynthetic phenotype of fibroblasts at a pretranslational level through a paracrine signalling pathway.
在本研究中，我们在体外人皮肤等效物中研究了角质形成细胞对成纤维细胞表型的影响。将角质形成细胞接种于成纤维细胞填充的机械约束I型胶原凝胶（网格）表面。无角质形成细胞的网格作为平行对照进行处理。培养2天和4天后，去除角质形成细胞层，通过Northern印迹和斑点印迹分析测定成纤维细胞产生的主要细胞外基质大分子和间质胶原酶的mRNA稳态水平。共培养2天和4天后，观察到I型和III型前胶原mRNA量减少50%，而与对照网格相比，胶原酶基因表达上调300%。未发现IV型和VI型胶原、弹性蛋白或层粘连蛋白B1 mRNA水平有明显调节。成纤维细胞中的纤连蛋白mRNA水平仅在第4天显著增加。使用从覆盖有角质形成细胞的网格收集的条件培养基添加到仅含成纤维细胞的网格中，可重现所有观察到的变化。这些结果表明，在体外重构皮肤中，角质形成细胞能够通过旁分泌信号通路在翻译前水平调节成纤维细胞的生物合成表型。
