Effect of granulocyte colony-stimulating factor on murine thymic emigration and subsets reconstitution after a sublethal dose of irradiation
10.3760/cma.j.issn.0254-5098.2011.06.009
- VernacularTitle:粒细胞集落刺激因子对急性辐射损伤小鼠胸腺细胞亚群及其近期输出功能的影响
- Author:
Hongxia ZHAO
;
Mei GUO
;
Xuedong SUN
;
Huisheng AI
- Publication Type:Journal Article
- Keywords:
Granulocyte colony-stimulating factor;
Irradiation;
Immunologic reconstitution
- From:
Chinese Journal of Radiological Medicine and Protection
2011;31(6):657-662
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the effects of recombinant human granulocyte colonystimulating factor(G-CSF) on murine thymic emigration and subsets reconstitution after a sublethal dose of irradiaton.Methods Female BALB/c mice were irradiated with a 6.0 Gy of γ-ray total-body irradiation and then randomly divided into GCSF group and control group.For mice in the GCSF group,recombinant human G-CSF 100 μg · kg-1 · d-1 was injected subcutaneously once daily for 14 continuous days and mice in the control group were given the same volume of phosphate buffered solution (PBS).At 7,14,21 and 28 days later,mice were killed and thymus mononuclear cell suspension were analyzed by flow cytometry for the percentage of the four stages of thymic CD4 -CD8 - double negative cells (DN1-4) and the CD4 + CD8 + double positive ( CD4 + CD8 + DP),CD4 + CD8 - single positive ( CD4 + SP),CD4 -CD8 + single positive cells (CD8 + SP).Real-time PCR was used for detection and quantitation of murine T cell receptor rearrangement excision circles(sjTRECs) of the thymic cells of 30 and 60 d after irradiation.Results The percentage of thymic DN1 cells in GCSF group was significantly higher than that of the control group 7 d after irradiation (t =9.59,P < 0.05 ).21 d later,the proportion of thymic DN3 and DN4 cells were higher than those of the control group ( t =16.37,7.6,P < 0.05 ).The percentage of thymic CD4 + CD8 + DP cells decreased 7 d after irradiation,increased at 14 d,decreased again at 21 days,and then got a permanent recover.The percentage of thymic CD4 + CD8 + DP cells in the GCSF group recovered to normal and was significantly higher than that of the control group 28 days after irradiation (t =12.22,P< 0.05).The percentage of thymic CD8 + SP cells of the GCSF group was significantly higher than that of the control group 21 d after irradiation ( t =3.77,P < 0.05 ),while G-CSF had no obvious influence on the percentage of the thymic CD4 + SP cells.The sjTRECs copies in the GCSF group was significantly higher than that of the control group 30 d after irradiation ( t =5.95,P < 0.01 ),which disappeared 60 d later.Conclusions G-CSF could promote the proliferation and differentiation of thymic DN and DP cells,enhance the recent thymic emigrants and accelerate central immunologic reconstitution after acute irradiation.