The role of IL-22 in T cell reconstitution after thymus damage induced by ionizing radiation
10.3760/cma.j.issn.0253-2727.2018.09.012
- VernacularTitle: IL-22在小鼠胸腺受损后T细胞免疫重建中的作用研究
- Author:
Fan XIA
1
;
Yujing WU
;
Zhenzhen LU
;
Kailin XU
;
Bin PAN
Author Information
1. Department of Hematology, the Affiliated Hospital of Xuzhou Medical University, Xuzhou 221002, China
- Publication Type:Journal Article
- Keywords:
IL-22;
Thymus;
Total body irradiation;
T cell reconstitution
- From:
Chinese Journal of Hematology
2018;39(9):761-765
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To explore the levels of IL-22 in thymus damaged by γ-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 Foxn1, Ccl25, Aire and Dll4 in thymus.
Results:①Sub-lethal TBI treated mice expressed higher levels of intra-thymic and circulatory IL-22, compared with untreated ones (all P<0.05). ②After injection of recombinant IL-22, TBI+IL-22 mice had higher levels of intra-thymic IL-22 than TBI+PBS mice (all P<0.05). ③On day 14 after irradiation, real-time PCR assay showed that TBI+IL-22 mice had higher mRNA levels of Foxn1, Ccl25, Aire and Dll4 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-22, and injecting of recombinant IL-22 increases level of IL-22 in thymus. Injecting of recombinant IL-22 improves recovery of TEC and increases numbers of thymocyte subsets and circulatory T cell after thymic injury.
