Genever P G, Wood E J, Cunliffe W J
Department of Biochemistry and Molecular Biology, Leeds University, UK.
Exp Dermatol. 1993 Dec;2(6):266-73. doi: 10.1111/j.1600-0625.1993.tb00043.x.
Dermal equivalents (DEs), fabricated by seeding fibroblasts into a collagen lattice, may be used as in vitro models for studying wounding and the remodelling processes observed in vivo. We investigated fibroblast responses to a wound stimulus in vitro by making small wounds in DEs. We found that, following wounding, fibroblasts appeared to migrate towards and into the wound defect and appeared to initiate the closure of the wound by bringing together the cut collagen surfaces over a period of 5-11 days. Fibroblast movement into the wound defects was significantly stimulated in the presence of EGF and PDGF (2.8- and 3.5-fold respectively) but not TGF-beta. Cell proliferation in wounded DEs was up to 21% greater than in non-wounded DEs and cell numbers were stimulated further by the addition of TGF-beta, EGF and PDGF (1.5-, 1.7- and 1.8-fold respectively). Wounded DEs also displayed a 2.1-fold increase in latent collagenase production followed by a 1.3-fold increase in active collagenase levels compared to non-wounded DEs. Staining actin fibers within fibroblasts using rhodamine-phalloidin showed that fibroblasts in DEs were under tension, but that this tension was lost upon wounding. Subsequently the stress fibers reappeared concomitantly with the observed "healing" process. Additionally a continuous cell-cell actin cable purse-string developed around the entire wound edge which may be involved in wound closure. The findings suggest that the wounded dermal equivalent offers a valuable model for studying wound healing in vitro.
通过将成纤维细胞接种到胶原晶格中制备的真皮替代物（DEs），可用作体外模型，以研究体内观察到的伤口愈合和重塑过程。我们通过在DEs上制造小伤口来研究成纤维细胞在体外对伤口刺激的反应。我们发现，受伤后，成纤维细胞似乎朝着伤口缺损处迁移并进入其中，并且似乎在5 - 11天的时间里通过将切开的胶原表面拉拢在一起，从而启动伤口的闭合。在表皮生长因子（EGF）和血小板衍生生长因子（PDGF）存在的情况下，成纤维细胞向伤口缺损处的迁移受到显著刺激（分别为2.8倍和3.5倍），但转化生长因子-β（TGF-β）则无此作用。受伤的DEs中的细胞增殖比未受伤的DEs高21%，并且添加TGF-β、EGF和PDGF后细胞数量进一步增加（分别为1.5倍、1.7倍和1.8倍）。与未受伤的DEs相比，受伤的DEs中潜在胶原酶的产生增加了2.1倍，随后活性胶原酶水平增加了1.3倍。用罗丹明 - 鬼笔环肽对成纤维细胞内的肌动蛋白纤维进行染色显示，DEs中的成纤维细胞处于张力状态，但受伤后这种张力消失。随后，应力纤维伴随着观察到的“愈合”过程重新出现。此外，在整个伤口边缘形成了一条连续的细胞 - 细胞肌动蛋白索状收缩环，这可能参与伤口闭合。这些发现表明，受伤的真皮替代物为体外研究伤口愈合提供了一个有价值的模型。
