神经生长因子p75受体与sortilin在皮肤及瘢痕成纤维细胞中的表达

Expression of nerve growth factor p75 receptor and sortilin in the skin fibroblasts and scar fibroblasts

背景:既往研究发现神经生长因子在创面愈合过程中发挥重要作用,但对于成纤维细胞中神经生长因子低亲和力受体p75及sortilin的研究较少,p75及sortilin在瘢痕组织成纤维细胞及正常皮肤组织成纤维细胞中的表达量是否有差异目前未见报道。目的:比较神经生长因子低亲和力受体p75及soritilin在瘢痕疙瘩成纤维细胞及正常皮肤成纤维细胞的中表达的差异。方法:体外培养瘢痕疙瘩成纤维细胞及正常皮肤成纤维细胞,并以人永生化上皮细胞HaCaT为阳性对照。通过实时定量PCR在mRNA水平检测p75及sortilin在瘢痕疙瘩成纤维细胞及正常皮肤成纤维细胞的表达及差异,进一步通过Western-blot及细胞免疫化学方法观察p75神经营养因子受体及sortilin在蛋白水平的表达及差异。结果与结论:实时定量PCR及Western blot结果可见,在mRNA及蛋白水平瘢痕疙瘩成纤维细胞及正常皮肤成纤维细胞中p75,sortilin均呈阳性表达,其中瘢痕疙瘩成纤维细胞及正常皮肤成纤维细胞中p75及sortilin在mRNA及蛋白水平表达量明显少于HaCaT,且p75在瘢痕疙瘩成纤维细胞及正常皮肤成纤维细胞中表达差异无显著性意义,sortilin表达量在瘢痕疙瘩成纤维细胞中明显低于正常皮肤成纤维细胞(P<0.05)。免疫细胞化学结果显示p75及sortilin在瘢痕疙瘩成纤维细胞及正常皮肤成纤维细胞中的表达部位均位于胞膜及胞浆。由于神经生长因子前体与p75受体高亲和力结合并在sortilin协助下发挥促进细胞凋亡的作用,sortilin在瘢痕成纤维细胞的表达明显低于正常皮肤成纤维细胞,可能与其高增殖状态有关,该结果为病理性瘢痕的防治提供了新的靶点。

OBJECTIVE： To study the expression of Iow-affility nerve growth factor receptor p75 and sortilin in the normal human skin fibroblasts and the human keloid fibroblasts. METHODS： The keloid fibroblasts and normal hunman skin fibroblasts were cultured in vitro, and theimmortalized epithelial cells HaCaT were used as the positive control. The real-time PCR was used to detect the mRNA expression of the p75 and sortUin in the keloid fibroblasts and normal human skin fibroblasts, and western blot and immunocytochemical staining were used to detect the protein expression of p75 and sortilin. RESULTS AND CONCLUSION： The real-time PCR and western blot results showed that in the protein and mRNA levels, p75 and sortilin showed positive expression in the keloid fibroblasts and normal human skin fibroblasts, and there was no significant difference in the expression of p75 between keloid fibroblasts and normal human skin fibroblasts, and the expressions of p75 and sortilin in the keloid fibroblasts and normal human skin fibroblasts were significantly lower than those in HaCaT. There was no significant difference of p75 expression between keloid fibroblasts and normal human skin fibroblasts, and the expression of sortilin in the keloid fibroblasts was significantly lower than that in the normal human skin fibroblasts （P 〈 0.05）. Immunocytochemical staining result showed that the expression of p75 and sortilin in the keloid fibroblasts and normal human skin fibroblasts were distributed in the membrane and cytoplasm. Precursor nerve growth factor combined with high-affinity p75 receptor could promote the apoptosis of the cells with the help of sortilin, and the expression of sortilin in the keloid fibroblasts was significantly lower than that in the normal human skin fibroblasts, which may associated with the high proliferation of the keloid fibroblasts. The results provide a new target for the prevention and treatment of pathological scars.sortilin; keloid fibroblast; normal skin fibroblasts; HaCaT; real-time PCR; western blot; National Natural Science Foundation of China