〔Abstract〕 Objective To explore the effects of intraperitoneal injection of tetramethylpiperidine(Tempol) on the interleukin(IL)-22 and IL-2 in the liver injury of trichloroethylene(TCE) sensitized mice and the influence of malondialdehyde(MDA) levels.Methods Forty 6～8 weeks Balb/c female mice were randomly sampled and divided into blank group, solvent group, TCE group and TCE+Tempol group to establish a TCE percutaneous sensitization model. The animals in TCE+Tempol group were injected intraperitoneally with Tempol solution(100 mg/kg)before the last challenge. 24 hours after the last challenge, the animals were divided into sensitization positive group or sensitization negative group according to the skin sensitization result score. The pathology of liver sections was observed by HE staining method, serum was separated for the detection of aspartate aminotransferase(AST) and alanine aminotransferase(ALT), and MDA content in liver was detected by TBA method, IHC and Western blot method to detect the expression level of IL-22 and IL-2 in liver tissue.Results The sensitization rates of TCE group and TCE + Tempol group were 0. 40 and 0. 33,respectively. Pathological examination found that the liver cells of the blank group,solvent group and non-sensitized group had no obvious pathological changes. There was a large number of vacuolar degeneration in the liver cells of the TCE sensitization positive group,with cell edema and cytoplasm in a loose state,while the TCE + Tempol sensitization positive group showed hepatocyte edema in some areas; Compared with the blank group,the MDA activity,IL-22 and IL-2 content in the liver tissue of mice in solvent group and sensitization negative group were not statistically significant. The relative expression levels of MDA,IL-22 and IL-2 in the liver tissue of mice in the sensitization positive group were higher than those in the solvent group and the sensitization negative group( P<0. 05),and the TCE sensitization positive group was higher than the TCE at the same point TCE + Tempol sensitization positive group( P<0. 05). Conclusion Tempol may reduce the levels of IL-22 and IL-2 to protect the immune liver injury caused by TCE.