rhIL-18对辐照小鼠免疫功能的调节作用

目的研究重组人白细胞介素18(rhIL-18)对辐照小鼠免疫功能的调节作用,探讨rhIL-18在辐照防护中的应用价值。方法将32只小鼠随机分为正常对照组、单纯辐射照射组、rhIL-18+辐射照射组、辐射照射+rhIL-18组,辐照剂量为60Coγ射线4.0Gy,rhIL-18为0.6mg腹腔注射,处理后分别用淋巴细胞转化实验、NK细胞毒实验、T淋巴细胞亚群检测,测定小鼠脾细胞体外培养上清中白细胞介素-2(IL-2)、γ-干扰素(IFN-γ)、单核巨噬细胞集落刺激因子(GM-CSF)、白细胞介素-4(IL-4)和血清中IgG的含量,观察rhIL-18对其免疫功能的调节作用。结果与单纯辐射照射组比较,rhIL-18能提高辐照后小鼠的T、B淋巴细胞转化能力(P0.05),使T、B淋巴细胞转化能力恢复或超过正常对照组水平,辐射照射后注射rhIL-18组的刺激指数达到了2.9〔刀豆蛋白A(ConA)组〕和6.1〔脂多糖(LPS)组〕;可促进辐照所致NK细胞活性抑制的恢复(P0.05),使NK细胞对肿瘤细胞杀伤率达到21.8%～35.6%;上调CD4T细胞数量,达到50个/ml(P0.05),提高辐照小鼠脾细胞分泌IFN-γ、GM-CSF和IL-2的能力(P0.05),但对IL-4分泌能力和IgG产生能力没有调节作用。结论rhIL-18具有促进辐照小鼠免疫功能恢复的作用。

EFFECT OF rhIL-18 ON IMMUNOREGULATION OF MICE WITH RADIATION DAMAGE

Objective To study the immunoregulation effect of rhlL-18 on irradiated mice. Methods Thirtytwo C57 mice were randomly divided into normal control group, irradiated group, rhlL- 18 ＋ irradiated group, irradiated ＋ rhlL-18 group. The animals were irradiated with ^60Co （y rays 4.0 Gy）and treated with rhlL-18 ahemately. After 2 weeks, the lymphocyte transform ability, NK cells cytotoxic activity, T cells subtype were examined, the levels of IL-2, IFN-γ,GM-CSF,and IL-4 in the supernatant of cultured splenocytes in vitro and content of IgG in serum were also test- ed. Results rhlL-18 could make T and B lymphocyte transform function of ^60Co irradiated mice to recover or even better than normal levels （ P 〈 0.05）. The stimulating index （SI） in irradiated ＋ rhIL-18 group reaehad to 2.9 （ConA test） and 6.1 （LPS test）, rhlL-18 could enhance cytotoxic activity mediated by NK cells against tumor cells of A375, U937 and KG1 cells. The rate of killing tumor cells by NK cells was 21.8 to 35.6% （ P 〈 0.05）. Moreover, rhIL-18 could upregulate the number of CD4 T cells to 50 cells/ml and improve splenocytes of irradiated mice to secret cytokines of IL-2, IFN-7, GM-CSF（ P 〈 0.05） but not IL-4 and IgG. Conclusion rhlL-18 could improve the immune function of irradiated mice.