摘要
目的探索γ射线照射诱导胸腺损伤后胸腺内IL-22表达水平的变化趋势，并研究IL-22在胸腺损伤后T细胞免疫重建中的作用。方法建立非致死剂量γ射线照射诱导的小鼠胸腺损伤模型，分别设置正常对照组和全身照射（TBI）组，ELISA法检测鼠胸腺及血浆中IL-22的含量；分别给予TBI组小鼠PBS或重组小鼠IL-22腹腔注射处理，设为TBI＋PBS组和TBI＋IL-22组，计数胸腺内总细胞和外周血白细胞含量，同时使用流式细胞术分析胸腺上皮细胞（thymic epithelial cells，TEC）、各阶段胸腺细胞以及外周血T细胞的含量，实时定量PCR分析胸腺中与TEC功能相关的基因Foxnl、Ccl25、Aire和D114的mRNA表达水平。结果①照射后小鼠胸腺内IL-22表达水平高于未经照射处理的正常对照小鼠（P值均〈0．05）；②给予TBI组小鼠IL-22腹腔注射后，TBI＋IL-22组小鼠胸腺内IL-22含量高于TBI＋PBS组（P值均〈0．05）；⑧照射后第14天，TBI＋IL-22组胸腺内Foxnl、Ccl25、Aire和Dll4mRNA表达水平均高于TBI＋PBS组（P值均〈0．05），同时，TBI＋IL-22组胸腺总细胞计数[（5．93±3．19）×106/ml对（1．42±0．46）×106／ml，t=3．128，P=0．033]和外周白细胞计数[（3．08±0．94）×106／ml对（1．43±0．30）×106／ml，t=3．730，P=0．015]均高于TBI＋PBS组。流式细胞术分析示，照射后第14天TBI＋IL-22组小鼠胸腺内TEC和各胸腺细胞亚群含量均高TBI＋PBS组（P值均〈0．05），照射后第7天和14天TBI＋IL-22组外周血T细胞含量均高于TBI＋PBS组（P值均〈0．05）。结论 γ射线照射处理可导致小鼠胸腺内IL-22的含量升高，注射外源性IL-22可增加胸腺内IL-22含量。输注外源性IL-22可促进受损胸腺内TEC功能的修复，并增加各胸腺细胞亚群以及外周血中T细胞的数量。
Objective To explore the levels of IL-22 in thymus damaged by 7-ray total body irradiation （TBI）, and to study the role of IL-22 in T cell reconstitution after thymic injury induced by TBI. Methods To induce thymic injury, mice were treated by sub-lethal TBI. Levels of intra-thymic and circulatory IL-22 were detected by using ELISA assay. Untreated mice were used as control. After receiving sub-lethal TBI, mice were intraperitoneally injected with PBS or recombinant mouse IL-22, which were marked as TBI＋ PBS or TBI＋ IL-22, respectively. Mice were monitored for counts of total thymic cells and circulatory white blood cells. Flow cytometry was applied to analyze percentages of thymic epithelial cells （TEC）, thymocyte subsets and circulatory T cells. Real-time PCR assay was applied to analyze the mRNA expression levels of Foxnl, Cc125, Aire and Dl14 in thymus. Results （1）Sub-lethal TBI treated mice expressed higher levels of intra-thymic and circulatory IL-22, compared with untreated ones （all P 〈 0.05）. （2）After injection of recombinant IL-22, TBI＋IL-22 mice had higher levels of intrathymic IL-22 than TBI＋PBS mice （all P 〈 0.05）. （3）On day 14 after irradiation, real-time PCR assay showed that TBI＋IL-22 mice had higher mRNA levels of Foxnl, Cc125, Aire and Dl14 in thymus compared with TBI＋PBS ones. Meanwhile, the TBI＋IL-22 mice had higher counts of total thymic cells [ （5.93±3.19）×106/ml vs （1.42±0.46） × 106/ml, t = 3.128, P = 0.033 ] and circulatory white blood cells [（3.08±0.94） × 106/ml vs （1.43 ±0.30）× 106/ml, t= 3.730, P= 0.015] than those of TBI ＋PBS mice. Flow cytometry analysis indicated that TBI＋IL-22 mice had higher counts of TEC and thymocytes than TBI＋PBS mice on day 14 after irradiation （all P〈 0.05）. On days 7 and 14 after irradiation, TBI＋IL-22 mice had higher counts of circulatory white blood cells and T cells than TBI＋PBS mice （all P 〈 0.05）. Conclusion Sub-lethal TBI induces upregulation of intra-thymic IL-2
作者
夏凡
武育菁
逯真真
徐开林
潘彬
Xia Fan;Wu Yujing;Lu Zhenzhen;Xu Kailin;Pan Bin(Department of Hematology,the Affiliated Hospital of Xu-zhou Medical University,Xuzhou 221002,China)
出处
《中华血液学杂志》
CAS
CSCD
北大核心
2018年第9期761-765,共5页
Chinese Journal of Hematology
基金
国家自然科学基金（81671584、81300377、81500088）
