title: [Effect of trichloroethylene intake via drinking water on Th17 cells in BALB/c mice].
abstract: OBJECTIVE
  This study aimed to investigate the effect of trichloroethylene (TCE) intake via drinking water on Th17 cells in mice.
  
  
  METHODS
  Forty eight six weeks old female BALB/c mice were divided into blank control, vehicle control, 2.5 mg/ml TCE and 5.0 mg/ml TCE groups by random number table (12 mice each group), and exposed to TCE by drinking water. On the 14(th), 28(th), 56(th), 84(th) days, blood were collected and assayed for IL-17, IL-6, and TGF-β concentration in serum through ELISA. Animals were killed and spleen biopsies were taken sterility. The proportion of Th17 cells among CD4(+) T cells and RORγt mRNA expression level in spleen were measured by FCM and real-time PCR.
  
  
  RESULTS
  In 2.5 mg/ml TCE and 5.0 mg/ml TCE group mice, Th17 cells/CD4(+) T cells in spleen were (3.46 ± 0.32)% and (5.45 ± 0.45)% on day 14, (3.47 ± 0.33)% and (4.10 ± 0.39)% on day 84, which were significantly higher than those for solvent control group at the same time point ((2.15 ± 0.20)%, (2.16 ± 0.35)%, respectively) (P < 0.01). RORγt mRNA expression levels were (1.870 ± 0.084) and (1.965 ± 0.060) on 14 day, (1.998 ± 0.079) and (2.028 ± 0.073) on day 56, which were also significantly higher than those for solvent control group at the same time point (1.77 ± 0.04 and 1.75 ± 0.09, respectively) (P < 0.05). IL-17 concentrations in serum were (32.28 ± 5.38) and (34.47 ± 5.02) pg/ml on day 14, and (34.87 ± 5.48) and (41.94 ± 6.19) pg/ml on day 28, which were significantly higher than those for solvent control group at the same time point((21.57 ± 5.23), (22.11 ± 5.11) pg/ml). IL-6 concentration in serum were (43.07 ± 6.71) and (47.86 ± 8.52) pg/ml on day14, (41.32 ± 7.04) and (46.74 ± 9.33) pg/ml on day 56, which were significantly higher than solvent control group at the same time point ((7.56 ± 7.71) and (28.26 ± 7.22) pg/ml). TGF-β concentration were (17.48 ± 3.06) and (18.93 ± 3.12) pg/ml on day 14, which did not show significant difference from solvent control group ((15.25 ± 2.95) pg/ml). Correlation analysis showed that IL-6 in serum were significantly positively correlated with the proportion of Th17 cells among CD4(+) T cells and RORγt expression level in spleen (r = 0.741, 0.765, P < 0.01).
  
  
  CONCLUSIONS
  TCE might promote the differentiation of Th17 cells and increase IL-17 secretion by inducing IL-6 and up-regulating RORγt expression together with TGF-β.
authors.affiliation: Department of Toxicology, School of Public Health, Anhui Medical University, Hefei 230032, China. Email: ahmusht@yahoo.com.cn.
authors.forename: Tong
authors.initials: T
authors.lastname: Shen
authors.forename: Jin
authors.initials: J
authors.lastname: Wang
authors.forename: Hui
authors.initials: H
authors.lastname: Xu
authors.forename: Shu-Hai
authors.initials: SH
authors.lastname: Xu
authors.forename: Tao
authors.initials: T
authors.lastname: Jiang
authors.forename: Qi-Xing
authors.initials: QX
authors.lastname: Zhu
mesh_terms: D000818:Animals; D060766:Drinking Water / Q000737:chemistry*; D005260:Female; D020381:Interleukin-17 / Q000276:immunology; D015850:Interleukin-6 / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D057132:Nuclear Receptor Subfamily 1, Group F, Member 3 / Q000276:immunology; D058504:Th17 Cells / Q000187:drug effects* / Q000276:immunology; D016212:Transforming Growth Factor beta / Q000276:immunology; D014241:Trichloroethylene / Q000633:toxicity*
chemical_list: D060766:Drinking Water; D020381:Interleukin-17; D015850:Interleukin-6; D057132:Nuclear Receptor Subfamily 1, Group F, Member 3; C539901:Rorc protein, mouse; D016212:Transforming Growth Factor beta; D014241:Trichloroethylene