title: The proinflammatory effect and molecular mechanism of IL- 17 in the intestinal epithelial cell line HT-29.
abstract: OBJECTIVE
  To evaluate the proinflammatory effect and molecular mechanism of IL-17 in the intestinal epithelial cell line HT-29.
  
  
  METHODS
  After culture of HT-29 cells with IL-17 and/or TNF-(α), real-time (RT) PCR and Western blot were used to measure the gene expression level of the neutrophil chemokines CXCL1, CXCL2, CXCL5, CXCL6, IL-8 and the Th-17 chemokine CCL20, the phosphorylation level of P38 and TNF-α, and the expression level of IL-8 after treatment with P38 inhibitor. Act1 stable knockdown HT-29 cell line was established to further test the change of P38 phosphorylation after treatment with IL-17 and TNF-α.
  
  
  RESULTS
  When HT-29 cells were cultured with IL-17 and TNF-α, the expression level of neutrophil chemokines (CXCL1, CXCL2, CXCL5, CXCL6, IL-8) and Th17 chemokine (CCL20) was significantly improved (24.96±2.53, 28.47±2.87, 38.08±2.72, 33.47±2.41, 31.7±2.38, 44.37±2.73, respectively) (p<0.01). The results of Western blot showed that IL-17 obviously enhanced the phosphorylation of P38 induced by TNF-α. Compared with the control group, the expression level of IL-8 declined significantly (9.47±1.36 vs 3.06±0.67) when HT-29 was cultured together with IL-17 and TNF-α (p<0.01). P38 inhibition assay showed that P38 pathway played an essential role in IL-17 induced inflammatory response. The level of P38 phosphorylation could not be changed after treatment with IL-17 and TNF-α in Act1 stable knockdown HT-29 cell line.
  
  
  CONCLUSIONS
  IL-17 significantly promoted the gene expression level of TNF-α-induced neutrophil chemokines and Th17 cells chemokine. IL-17 and TNF-α have an obvious synergistic effect on P38.
authors.affiliation: Department of Cardiology, Central Hospital of Hubei Xiangyang, Xiangyang, Hubei, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Zhang
authors.forename: Ge
authors.initials: G
authors.lastname: Wang
authors.forename: Yun
authors.initials: Y
authors.lastname: Tao
authors.forename: Hua
authors.initials: H
authors.lastname: Zhang
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D018925:Chemokines / Q000235:genetics / Q000378:metabolism*; D004847:Epithelial Cells / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D005786:Gene Expression Regulation; D055785:Gene Knockdown Techniques; D019073:HT29 Cells; D006801:Humans; D018836:Inflammation Mediators / Q000378:metabolism*; D015212:Inflammatory Bowel Diseases / Q000276:immunology / Q000378:metabolism; D020381:Interleukin-17 / Q000494:pharmacology*; D007413:Intestinal Mucosa / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D010766:Phosphorylation; D034622:RNA Interference; D015398:Signal Transduction / Q000187:drug effects; D013997:Time Factors; D014162:Transfection; D047988:Tumor Necrosis Factor Receptor-Associated Peptides and Proteins / Q000235:genetics / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D018925:Chemokines; D018836:Inflammation Mediators; D020381:Interleukin-17; C414202:TRAF3IP2 protein, human; D047988:Tumor Necrosis Factor Receptor-Associated Peptides and Proteins; D014409:Tumor Necrosis Factor-alpha; D048051:p38 Mitogen-Activated Protein Kinases