Immune cytotoxicity of trichloroethylene and its mechanism in activated human T cells / 中国职业医学

ABSTRACT

OBJECTIVE: To explore the immune cytotoxicity effect and its mechanism of trichloroethylene( TCE) on activated human T cells. METHODS: a) Different concentrations of TCE( 0. 32,0. 63,1. 25,2. 50,5. 00,10. 00 mmol / L)were used to treat activated T cells [activated with cluster of differentiation( CD) 3 and CD28] respectively. Dimethyl sulfoxide( DMSO) was used in the solvent group and the control group used no TCE or DMSO. The survival rate of activated T cells was calculated using CCK-8 assay after being cultured for 24 hours. b) Different concentrations of TCE( 0. 00,2. 50,5. 00 mmol/L) were used to treat activated T cells. The apoptosis of cells was detected using flow cytometry. c) Different concentrations of TCE( 0. 00,0. 32,0. 63,1. 25,2. 50,5. 00 mmol / L) were used to treat activated T cells and the level of cytokines as interleukin( IL)-2 and IL-6 in cell culture supernatant was detected using enzyme linked immunosorbent assay after culturing for 24 hours. d) The control group and TCE treatment group of activated T cells were treated with 0. 00 and 5. 00 mmol / L TCE respectively. Cells were collected after culturing 0,30,60 and 120 minutes. Western Blot was used to detect the protein expression of signal transducers and activators of transcription3( STAT3) and phospho-STAT3( p-STAT3). RESULTS: a) After 24-hour-exposure to TCE,the activated T cell survival rate of 10. 00 mmol / L TCE treatment group were significantly lower than that in the control group and DMSO group( P <0. 05). b) There were no significant differences in cell apoptosis of activated T cells after treatment with 0. 00,2. 50 and5. 00 mmol / L TCE( P > 0. 05). c) In groups treated with different concentrations of TCE( 0. 32,0. 63,1. 25,2. 50,5. 00 mmol / L),the level of IL-2 and IL-6 in the cell culture supernatant of activated T cells were significantly higher than that in the control group( P < 0. 05). With the increasing of TCE exposure doses,the levels of IL-2 and IL-6 significantly increased( P < 0. 01) with dose-effect relationship. Compared with the control group,the levels of IL-17 A,interferongamma and transforming growth factor-beta in cell culture supernatant of activated T cells of the TCE treatment groups were no significant differences( P > 0. 05). d) The expression of p-STAT3 protein was low in the control group at different times. The expression of p-STAT3 protein in TCE treatment group was low at 0 minute,but increased at 30,60,120 minutes. The expression of p-STAT3 protein in TCE treatment group was higher than that in the control group at different time points. The levels of STAT3 total protein in TCE treatment group and the control group were similar at different time points,and were higher than the p-STAT3 proteins. CONCLUSION: TCE at 5. 00 mmol / L had no observed toxic effect on activated T cells. High doses of TCE( ≥10. 00 mmol / L) showed cytotoxic damages to activated T cells,and low doses of TCE( ≤5. 00 mmol / L) could stimulate activated T cells to secrete IL-2 and IL-6. Treatment of TCE at 5. 00 mmol / L on activated T cells could up-regulated the level of p-STAT3.