Purpose

We investigated healing pattern of an incisional wound in corneal stroma of lumican-null (KO) mice.

Methods

C57BL/6 mice (wild-type, WT) and lumican-null (knockout, KO) mice were used. A linear full-thickness incision was produced in one cornea of each mouse. After intervals of healing, the corneas were processed for the following analyses. Histology was employed to measure the distance between each edge of the disrupted Descemet's membrane at the center of the cornea. Immunohistochemistry and real-time RT-PCR were employed to evaluate the expression of wound healing-related components in the tissue. Cultured ocular fibroblasts were obtained from cornea and sclera of WT and KO postnatal day 1 pups. The cells were subjected to examination for cell proliferation and expression of wound healing-related gene products. In vitro gel contraction assay was used to asses cell contractile activity of WT and KO cells.

Results

At day 5 of incision, the distance between the disrupted Descemet's membrane was larger in a KO mouse as compared with a WT mouse. Myofibroblast appearance in the wound was suppressed by the loss of lumican. The loss of lumican downregulated TGFβ1's effects on mRNA expression of α-smooth muscle actin and collagen Ia1 in cultured ocular fibroblasts. Cell proliferation rate increased in injured stroma, which was further supported by in vitro datum of cell proliferation augmentation by the loss of lumican. Loss of lumican suppressed cell-mediated gel contraction.

Conclusion

Loss of lumican perturbs the healing of penetrating incision in mouse corneal stroma in association with suppression of myofibroblast generation.

中文翻译：

---

Lumican 缺失小鼠角膜基质切口愈合受损

目的

我们研究了 Lumican-null (KO) 小鼠角膜基质切口伤口的愈合模式。

方法

使用 C57BL/6 小鼠（野生型，WT）和 Lumican-null（敲除，KO）小鼠。在每只小鼠的一个角膜上产生线性全层切口。经过一段时间的愈合后，对角膜进行处理以进行以下分析。采用组织学来测量角膜中心破坏的后弹力层各边缘之间的距离。采用免疫组织化学和实时RT-PCR来评估组织中伤口愈合相关成分的表达。从WT 和 KO 出生后第 1 天幼犬的角膜和巩膜中获得培养的眼成纤维细胞。对细胞进行细胞增殖和伤口愈合相关基因产物表达的检查。使用体外凝胶收缩测定来评估WT和KO细胞的细胞收缩活性。

结果

在切口第 5 天，与 WT 小鼠相比，KO 小鼠中破坏的后弹力层之间的距离更大。伤口中肌成纤维细胞的出现因lumican的损失而受到抑制。lumican 的缺失下调了 TGFβ1 对培养的眼成纤维细胞中 α-平滑肌肌动蛋白和胶原蛋白 Ia1 mRNA 表达的影响。受损基质中的细胞增殖率增加，这得到了由于lumican损失而增强细胞增殖的体外数据的进一步支持。lumican 的损失抑制了细胞介导的凝胶收缩。

结论

lumican 的缺失会干扰小鼠角膜基质穿透性切口的愈合，并与肌成纤维细胞生成的抑制相关。