rhIL-17A对人皮肤角质形成细胞和成纤维细胞活性和凋亡的影响

目的: 研究重组人白细胞介素17A (rhIL-17A)对人角质形成细胞和成纤维细胞活性、凋亡及成纤维细胞促纤维化因子分泌的影响,探讨IL-17在系统性硬皮病发病中的作用。方法: 用不同浓度的rhIL-17A作用于角质形成细胞和成纤维细胞,CCK-8测定其对角质形成细胞和成纤维细胞活性的影响;Western blotting 检测核转录因子NF-κB/p65及其抑制性蛋白IκBα的表达量;流式细胞术观察细胞凋亡变化;ELISA 检测rhIL-17A 处理组和对照组成纤维细胞培养液上清中IL-6和TGF-β₁的含量。结果: rhIL-17A处理组和对照组角质形成细胞活性没有明显差别;rhIL-17A 处理组成纤维细胞活性较对照组明显升高(P<0.05),rhIL-17A 处理组成纤维细胞NF-κB/p65表达量增加,而IκBα表达量降低;rhIL-17A 对2种细胞凋亡率无明显影响;rhIL-17A 处理组成纤维细胞IL-6 和TGF-β₁分泌量增加。结论: rhIL-17A对体外培养人角质形成细胞的活性没有明显影响,却可以显著增强体外成纤维细胞的活性,IL-17A对成纤维细胞活性增强的这种促进作用,可能是通过激活NF-κB实现。rhIL-17A可能通过刺激成纤维细胞分泌IL-6 和TGF-β₁,从而进一步引起成纤维细胞增殖和胶原合成。IL-17可能参与了系统性硬皮病的发病过程。

Effects of rhIL-17A on viability and apoptosis of human skin keratinocytes and fibroblasts in vitro

AIM: To investigate the effects of recombinant human interleukin-17A (rhIL-17A) on the viability and apoptosis of human skin keratinocytes and fibroblasts, and to observe the secretion of profibrotic cytokines by fibroblasts. METHODS: Human skin keratinocytes and fibroblasts were treated with different concentrations of rhIL-17A. CCK-8 method was used to test the cell proliferation. The protein expression of nuclear factor-κB/p65 (NF-κB/p65) and IκBα was determined by Western blotting. The cell apoptosis was observed by flow cytometry. The secretion of interleukin-6 and transforming growth factor-β₁ in the culture supernatants of fibroblasts was assayed by ELISA. RESULTS: No difference of the keratinocyte numbers between rhIL-17A treatment groups and control group was observed, while the numbers of fibroblasts were higher in rhIL-17A treatment groups than that in control group (P<0.05). The protein expression of NF-κB/p65 increased in fibroblasts with rhIL-17A treatment, while the expression of IκBα decreased. rhIL-17A had no effect on the apoptosis of both keratinocytes and fibroblasts. The secretion of interleukin-6 and transforming growth factor-β₁ in fibroblasts increased after treated with rhIL-17A. CONCLUSION: rhIL-17A had no effect on the proliferation of keratinocytes. However, it can enhance the proliferation of fibroblasts. This effect may be attributed to the activation of NF-κB in fibroblasts by interleukin-17. It is possible that rhIL-17A causes the cell proliferation and collagen synthesis by stimulating fibroblasts to secrete interleukin-6 and transforming growth factor-β₁.