Fujikawa L S, Foster C S, Harrist T J, Lanigan J M, Colvin R B
Lab Invest. 1981 Aug;45(2):120-9.
Fibronectin, a glycoprotein present in plasma and extracellular matrix, is believed to be involved in cell-cell and cell-matrix interactions. Using immunofluorescence techniques, we studied the time course of appearance and distribution of fibronectin in healing rabbit corneal epithelial wounds and compared fibronectin to other selected proteins in the cornea. In the normal cornea, fibronectin was detected only in Descemet's membrane and not in the epithelial basement membrane. Shortly after wounding, fibronectin deposited on the denuded corneal surface and was a continuous prominent layer by 8 hours. The epithelium had begun to migrate over the deposited fibronectin by 22 hours and by 52 hours had completely covered the denuded surface. Fibrinogen/fibrin was also detected on the initial bare wound surface. Once the wound was reepithelialized, the subepithelial fibronectin and fibrin layer then progressively disappeared, so that by 2 weeks only a small amount was detected. Fibronectin also appeared in the deep stroma of corneas after wounding in elongated patches, a pattern suggestive of keratocyte association. Fibronectin had an inverse relationship to bullous pemphigoid antigen which was used as a marker for the lamina lucida of the epithelial basement membrane. The bullous pemphigoid antigen, which was found in the normal corneal epithelial basement membrane, was removed with the epithelium and reappeared during the wound healing when fibronectin was diminishing. IgG and albumin did not localize on the wound surface, and the diffuse staining seen in the stroma did not change during healing. These findings are compatible with the hypothesis that fibronectin and fibrin play a role in epithelial migration and temporary adhesion to the surface during corneal wound healing, at a time when the normal anchoring mechanism is lost.
纤连蛋白是一种存在于血浆和细胞外基质中的糖蛋白，被认为参与细胞间和细胞与基质的相互作用。我们运用免疫荧光技术，研究了纤连蛋白在兔角膜上皮伤口愈合过程中的出现时间、分布情况，并将纤连蛋白与角膜中其他选定的蛋白质进行了比较。在正常角膜中，仅在Descemet膜中检测到纤连蛋白，而在上皮基底膜中未检测到。受伤后不久，纤连蛋白沉积在裸露的角膜表面，到8小时时形成连续的显著层。到22小时时上皮细胞已开始在沉积的纤连蛋白上迁移，到52小时时已完全覆盖裸露表面。在最初的裸露伤口表面也检测到了纤维蛋白原/纤维蛋白。一旦伤口重新上皮化，上皮下的纤连蛋白和纤维蛋白层随后逐渐消失，因此到2周时仅检测到少量。受伤后，纤连蛋白也以细长斑块的形式出现在角膜深层基质中，这种模式提示与角膜细胞有关联。纤连蛋白与用作上皮基底膜透明层标志物的大疱性类天疱疮抗原呈负相关。在正常角膜上皮基底膜中发现的大疱性类天疱疮抗原，随着上皮细胞被去除，在伤口愈合时纤连蛋白减少时重新出现。IgG和白蛋白未定位在伤口表面，基质中看到的弥漫性染色在愈合过程中没有变化。这些发现与以下假设相符：在角膜伤口愈合过程中，当正常的锚定机制丧失时，纤连蛋白和纤维蛋白在角膜上皮迁移以及与表面的临时黏附中发挥作用。
