An experimental method for direct detection of lymphocyte γ-H2AX in mice peripheral blood and its application
10.3760/cma.j.cn112271-20240622-00232
- VernacularTitle:经小鼠外周血直接检测淋巴细胞γ-H2AX的方法及应用
- Author:
Lei SHI
1
;
Xing SHEN
;
Ya DONG
;
Qiaoyun ZHANG
;
Hongling OU
;
Xiujun SONG
;
Yingying MA
;
Xinru WANG
Author Information
1. 锦州医科大学火箭军特色医学中心研究生培养基地，北京 100088
- Publication Type:Journal Article
- Keywords:
Flow cytometry;
Gamma rays;
γ-H2AX;
Dose-effect relationship
- From:
Chinese Journal of Radiological Medicine and Protection
2025;45(1):18-23
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To develop a method of employing flow cytometry to directly detect the γ-H2AX expression levels in peripheral blood lymphocytes of mice through fixation and lysis and to evaluate the feasibility of applying this method to research on the radiation-related biological effects and the efficacy evaluation of radioprotective drugs.Methods:A total of 41 male C57BL/6J mice were used. First, 21 mice were randomly divided into 7 groups according to different radiation doses (0, 1, 2, 4, 6, 8, and 10 Gy) with 3 mice in each group. Blood samples were collected from the tail vein of mice at 1, 4, 8, and 24 h after irradiation and immediately fixed with formaldehyde. Red blood cells (RBC) were lysed with Triton X-100, and γ-H2AX was labeled with specific antibodies. DRAQ5 dye was used to further exclude debris and anucleate cells. The mean fluorescence intensity of γ-H2AX in lymphocyte populations was directly analyzed by flow cytometry through forward and side scatter, and dose-effect curves after irradiation were established. Then, the other 20 mice were divided into radiation alone groups and radiation combined with WR-2721 administration groups at 4 and 6 Gy, respectively, with 5 mice in each group. Blood samples were collected from the tail vein of mice at 1, 4, 8, and 24 h after irradiation to detect the average fluorescence intensity of γ-H2AX in lymphocytes, which was used to evaluate the degree of DNA damage in mice and the therapeutic effect of WR-2721.Results:The expression of γ-H2AX in peripheral blood lymphocytes of mice significantly increased with the increase of radiation doses, and reached a peak at 1-2 h and then decreased. The dose-effect relationship was significant ( R2 = 0.9914). At 24 h after 4 and 6 Gy irradiation, compared with the radiation alone groups, the average fluorescence intensity of γ-H2AX in the radiation combined with WR-2721 administration groups was lower (144.8 ± 8.0 and 109.5 ± 9.7, vs. 178.0 ± 18.5 and 136.6 ± 5.4), with statistically significant difference ( t = 3.78, 5.48, P < 0.05). The average fluorescence intensity of γ-H2AX at 24 h after irradiation was consistent with the lowest values of the three blood cell lines at 7 or 14 d after irradiation. Conclusions:The application of flow cytometry with a fixation/dissolution protocol to directly detect the mean fluorescence intensity of γ-H2AX in peripheral blood lymphocytes of mice has significant application value in radiation biology effect research, radiation protection drug screening, and efficacy evaluation.
