紫外线及其辐射的尿刊酸对朗格汉斯细胞功能影响的研究

Effects of UVB and UV irradiated UCA on the Function of Langerhans′ Cell

目的探讨紫外线及其辐射的尿刊酸免疫抑制作用的可能机理。方法观察中波紫外线（ UVB）及尿刊酸对豚鼠朗格汉斯细胞刺激自体淋巴细胞增殖能力的影响。结果低剂量 UVB（ 25 J/m2）抑制率为 10.5％， 50 J/m2抑制率为 22.4％ , 100 J/m2抑制率为 54.5％， 200 J/m2几乎可以完全抑制朗格汉斯细胞协同刺激功能。 70％顺式尿刊酸 (0.2 mg/mL)抑制率仅为 13.4％，反式尿刊酸无抑制作用。结论紫外线可直接抑制朗格汉斯细胞的功能，并呈剂量依赖性，这可能在 UVB免疫抑制过程中起着重要的作用。经紫外线辐射的顺式尿刊酸抑制作用轻微。

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.