Illustrations
Figure 1
Effect of IL-17A on cell proliferation in HK-2 cells. (A)In dose-dependent experiments, Doses from 20 to 80 ng/mL of IL-17A promoted proliferation of HK-2 cells in a dose-dependent manner, and cell proliferation began to decline when the concentration of IL-17A was higher than 80 ng/mL as determined using a CCK-8 assay. (B) IL-17(80 ng/mL) promoted proliferation of HK-2 cells in a time-dependent manner as determined using a CCK-8 assay.*p <0.05, compared with control.
Figure 1
Figure 2
Effect of IL-17A, TGF-β1 and TGF-β1 antibody on protein expression of α-SMA, collagen I and III and E-cadherin in HK-2 cells as shown by western blotting. HK-2 cells were incubated with or without IL-17A (80 ng/mL) for 72 h. TGF-β1 antibody (2 μg/mL) was added 2 h before the IL-17A treatment. TGF-β1(10 ng/mL) was the positive control. The expression of E-cadherin, collagen I and III, and α-SMA was analyzed by Western blotting. A) The results of western blotting. B) IL-17A and TGF-β1 decreased expression of E-cadherin protein; blocking TGF-β1 with TGF-β1 antibody, expression of E-cadherin protein recovered in HK-2 cells treated with IL-17A;TGF-β1 antibody alone promoted expression of E-cadherin protein. C) IL-17A and TGF-β1 stimulated expression of α-SMA protein; blocking TGF-β1 with TGF-β1 antibody weakened expression of α-SMA protein. D, E) IL-17A and TGF-β1 induced production of collagen I and III in HK-2 cells, but with the addition of TGF-β1 antibody at the same time, production of collagen I and III both decreased. *p <0.05, compared with control. # p <0.05, compared with IL-17A group.
Notes: 1 normal control group. 2. IL-17A group. 3. IL-17A+TGF-β1 antibody group. 4. TGF-β1 antibody group. 5. TGF-β1 group.
Figure 2
Figure 3
Effect of IL-17A, TGF-β1 and TGF-β1 antibody on protein expression of α-SMA and E-cadherin in HK-2 cells by immunocytochemistry. HK-2 cells were incubated with or without IL-17A (80 ng/mL) for 72 h. TGF-β1 antibody (2 μg/mL) was added 2 h before the IL-17A treatment. TGF-β1 (10 ng/mL) was the positive control. A) IL-17A and TGF-β1 attenuated expression of E-cadherin protein; Blocking TGF-β1 with TGF-β1 antibody, caused expression of E-cadherin protein recover. B) IL-17 and TGF-β1 promoted expression of α-SMA; blocking TGF-β1 with TGF-β1 antibody decreased α-SMA expression. *p <0.05, compared with control. p <0.05, compared with IL-17A group.
Figure 3
Figure 4
Effect of IL-17A, TGF-β1 and TGF-β1 antibody on mRNA expression of α-SMA and E-cadherin in HK-2 cells by RT-PCR. HK-2 cells were incubated with or without IL-17A (80 ng/mL) for 72 h. TGF-β1 antibody (2 μg/mL) was added 2 h before IL-17A treatment. TGF-β1 (10 ng/mL) was the positive control. A) IL-17A and TGF-β1 downregulated mRNA expression of E-cadherin. Blocking TGF-β1 with TGF-β1 antibody, the mRNA expression of E-cadherin recovered in HK-2 cells treated with IL-17A. B) In IL-17A and TGF-β1 groups, the mRNA expression of α-SMA increased. On blocking TGF-β1 with TGF-β1 antibody, the mRNA expression of α-SMA decreased. *p< 0.05, compared with control. p< 0.05, compared with IL-17A group.
Notes: 1. normal control group. 2. IL-17A group. 3. IL-17A+TGF-β1 antibody group. 4. TGF-β1 antibody group. 5. TGF-β1 group.
Figure 4
Auteurs
1 Department of Nephrology, Affiliated Hospital of Luzhou Medical College, Luzhou City 646000,Sichuan Province, China
2 Department of Nephrology, West China Hospital of Sichuan University, Chengdu City610041, Sichuan Province, China
3 Department of Nephrology, Shanghai general hospital, Shanghai Jiao Tong University, Shanghai City 200080, China
4 Department of Central Service, West China Hospital of Sichuan University, Chengdu City 610041, Sichuan Province, China
5 State Key Laboratory of Biotherapy of Human Disease, West China Hospital, Sichuan University, Chengdu City 610041, Sichuan Province, China.
6 People's Hospital of Jianyang, Ziyang City 641400, Sichuan Province, China.
a The authors contributed equally to this article.
Background Renal interstitial fibrosis (RIF) is a pathological change common to a variety of chronic renal diseases, ultimately progressing to end-stage renal failure. It is believed that epithelial cell phenotype inversion plays an important role in RIF, which is characterized by expression of the mesenchymal maker α-SMA, loss of the epithelial maker E-cadherin, and enhanced secretion of extracellular matrix. IL-17, a newly discovered pro-inflammatory cytokine, has recently been reported to play an important role in tissue fibrosis, involving pulmonary, liver, intestine and skin tissues. This study aimed to investigate whether IL-17A, a member of the IL-17 family, can induce epithelial cell phenotype inversion, and to explore the molecular mechanism of this phenotype inversion, in vitro .