Aim: To study immunoinhibitory effects and preliminary mechanism of IL-10 and trichosanthin.
Methods: Surface molecule expression on antigen processing cells (APC) was stained with fluorescence and analyzed by FACScan. B7-1 mRNA expression was detected with nested RT-PCR.
Results: IL-10 2 mg.L-1 and trichosanthin 10 mg.L-1 inhibited B7-1 molecule expression. By contrast, they had not the same effects on ICAM-1. IL-10 and trichosanthin down-regulated LFA-1 expression, but had no regulatory effect on CD40. IL-10 and trichosanthin dramatically inhibited T-cell proliferation and IL-2 production. B7-1 mRNA expression was undetectable in APC treated with IL-10 and trichosanthin.
Conclusion: IL-10 and trichosanthin inhibit surface molecule expression on APC. They exert multiple immunoinhibitory effects.