Division of Oral Surgery, Nihon University School of Medicine, Tokyo, Japan.
Division of Physiology, Nihon University School of Medicine, Tokyo, Japan.
In Vivo. 2023 Jul-Aug;37(4):1486-1497. doi: 10.21873/invivo.13233.
BACKGROUND/AIM: Fibrosis is an essential process for wound healing, but excessive fibrosis, such as keloids and hypertrophic scars, can cause cosmetic and functional problems. These lesions are caused by abnormal deposition and shrinkage of collagen fibers. The light chain of FIX, a plasma protein essential for hemostasis, has the amino acid sequence CXDXXXXYXCXC in the EGF domain. Peptides containing this sequence inhibited stromal growth in a mouse transplant tumor model. In this study, the effect of the FIX light chain on wound healing was studied.
A full-layer wound was made on the back of each mouse, and cDNA encoding the light chain of mouse FIX (F9-LC) in an expression vector was injected locally once each week using a non-viral vector. Histochemical analysis of the wound was then performed to assess the effects on wound healing. Moreover, the effect of F9-LC on fibroblasts was studied in vitro.
Macroscopic observation showed that wounds with forced expression of F9-LC appeared flatter and had fewer wrinkles than control wounds. Tissue collagen staining and immunostaining revealed that administration of F9-LC suppressed collagen 1 and 3 deposition and decreased α-smooth muscle actin expression. Electron microscopy revealed sparse and disorganized collagen fibers in the F9-LC-treated mice. In experiments using fibroblasts, addition of a recombinant protein of the FIX light chain disrupted the typical spindle shape and alignment of fibroblasts.
F9-LC is a new candidate for use in treatments to regulate excessive fibrosis and contraction in wound healing.
背景/目的：纤维化是伤口愈合的必要过程，但过度纤维化，如瘢痕疙瘩和增生性瘢痕，会导致美容和功能问题。这些病变是由胶原纤维的异常沉积和收缩引起的。FIX 轻链，一种对止血至关重要的血浆蛋白，在 EGF 结构域中具有氨基酸序列 CXDXXXXYXCXC。含有该序列的肽在小鼠移植肿瘤模型中抑制了基质生长。在这项研究中，研究了 FIX 轻链对伤口愈合的影响。
在每只小鼠的背部制造全层伤口，并用非病毒载体每周局部注射一次表达载体中编码小鼠 FIX 轻链（F9-LC）的 cDNA。然后对伤口进行组织化学分析，以评估对伤口愈合的影响。此外，还在体外研究了 F9-LC 对成纤维细胞的影响。
宏观观察表明，强制表达 F9-LC 的伤口比对照伤口更平坦，皱纹更少。组织胶原染色和免疫染色显示，F9-LC 的给药抑制了胶原 1 和 3 的沉积，并减少了α-平滑肌肌动蛋白的表达。电子显微镜显示，F9-LC 处理的小鼠中的胶原纤维稀疏且排列紊乱。在成纤维细胞实验中，添加重组 FIX 轻链蛋白会破坏成纤维细胞的典型纺锤形和排列。
F9-LC 是一种新的候选药物，可用于调节伤口愈合过程中的过度纤维化和收缩。
