全身辐射对小鼠巨噬细胞IL-12表达影响的实验研究

Influence of total body irradiation on IL-12 expression in murine macrophages

目的 探讨γ射线全身照射对小鼠腹腔巨噬细胞数量、形态和IL 12基因表达影响的时效和量效特点 ,为放射损伤后的免疫调控提供理论依据。方法 小鼠一次性全身照射 ,于不同时相点分离、计数腹腔巨噬细胞 ,并观察其形态学变化 ,RT PCR法检测其IL 12p35和p40的基因转录水平。结果 ①伤后巨噬细胞数量早期减少 ,后期恢复 ;②伤后巨噬细胞呈多形性和纤维状 ;③伤后IL 12p35转录水平降低 ,而p40转录水平增加 ;④照射剂量越大 ,巨噬细胞损伤效应越重 ,恢复越慢。伤后 7d内以损伤改变为主 ,15d后以再生修复、功能恢复为主。结论 全身照射后巨噬细胞数量减少 ,形态改变 ,以及IL 12p35的减少和p40 p40的增加 ,可能是免疫障碍的重要环节。只有同时检测IL 12p35和p40才能正确反映放射损伤后IL

Objective\ To investigate the influence of total body irradiation(TBI)on the cell count,morphology and IL 12 transcriptive level of peritoneal macrophages(pMs). Methods\ At different timepoints post TBI,pMs were purified,counted and observed under microscope,and the transcriptive level of IL 12 subunits was detected with RT PCR. Results\ After irradiation:①pMs decreased on days 3 and 7,then partially recoveved on days 15 and 30;②pMs looked like polymorphic and fibriform;③IL 12 p35 transcription was suppressed while that of p40 was elevated;④the higher the dose,the more serious the damage and the slower its recovery.The damage was predominant within 7 days,while the recovery become evident beginning from day 15 after radiation. Conclusion\ Reduction and transfiguration of pMs,suppression of IL 12 p35 transcription and elevation of IL 12 p40 transcription might be important contributors of immunity suppression.Only combination of p35 transcription with that of p40 should be used appropriately to evaluate the state of IL 12 expression after irradiation.