RESUMO
Objective To investigate role of N-(30,40-dimethoxycinnamonyl) anthranilic acid (3,4-DAA) in mediating the negative immune regulation by indoleamine 2,3-dioxygenase in mice skin transplantation.Method The mice skin transplant model was established.T lymphocytes were isolated from mice splenocytes,and serum was collected.ELISA was applied to detect the IL-2 and IFN-γ concentrations in culture supernates of mice spleen lymphocytes and serum.Flow cytometry was applied to examine the phenotypes of T lymphocytes and RT-PCR to analyze the IDO mRNA transcription.Results T lymphocyte proliferation was significantly decreased by 3,4-DAA and the concentrations of IL-2 and IFN-γ were apparently decreased in 3,4-DAA group as compared with those in control group.The percentages of CD3 +,CD4 + and CD8 + T lymphocytes were lower,and the percentage of CD4 + CD25 + T lymphocytes was higher in 3,4-DAA disposal group than in control group,but there was no significant difference.IDO mRNA expression showed obvious increase in 3,4-DAA group as compared with control group.Conclusion 3,4-DAA can up-regulate the IDO expression to induce the increasing metabolism of tryptophan,subsequently inhibiting T cell proliferation and showing specific property of negative immune regulation.