Abstract:

Objective To study the immunosuppression mechanism induced by ultraviolet (UV)and cis urocanic acid. Method The auto lymphocyte proliferation test with Langerhans'cell (LC)in guinea-pig was performed. Results In exposure to low dose of UVB (25 J/m²) radiation,the inhibition rate of lymphocyte proliferation stimulated by LC was 10.5%,the inhibition rates of UVB radiation in doses of 50 J/m² and 100 J/m² were 22.4% or 50%,respectively. The lymphocyte proliferation was almost completely suppressed by 200 J/m² UVB radiation,while the inhibition of LC function by cis-urocanic acid was weak. Conclusion UVB significantly inhibits LC auto-stimulation in dose-dependent way,which may play an important role in UVB induced immunosuppression.

Key words: Ultraviolet rays, Urocanic acid, Langerhans cells, Immunosuppression