The injuries of spleen and intestinal immune system induced by 2-Gy ⁶⁰Co γ-ray whole-body irradiation

Abstract

Purpose

The aim of the present study was to investigate the injuries of spleen and intestinal immune system induced by 2 Gy ⁶⁰Co γ ray in mice.

Materials and methods

A total of 120 Balb/c mice were randomly divided into two groups: blank control (Ctrl) and model (IR). The IR mice were exposed to a single dose of total body irradiation (2 Gy, dose rate: 1 Gy/min) and sacrificed on 1st, 3rd, 7th, 14th and 21st day after irradiation. The indicators including general observations and body weight, the changes in peripheral hemogram, spleen index, histopathology examination and lymphocyte subsets of spleen. As well as the count and subsets of lymphocyte in gut-associated lymphoid tissue.

Results

Compared with the Ctrl group, the body weight, spleen index, peripheral blood cell and splenocyte amounts, intraepithelial lymphocytes number decreased significantly after exposure, accompanied by a notable decreased count of lymphocytes in Peyer’s patch and mesenteric lymph nodes. Moreover, ionizing radiation also broke the balance of CD4+/CD8+ and increased the Treg proportion in spleen, which then triggered immune imbalance and immunosuppression. In general, the spleen injuries occurred on 1st day after exposure, worse on 3rd day, and were relieved on 7th day. The intestinal immune injuries were observed on 1st day, and attenuated on 3rd day. On 21st day after exposure, the spleen volume and index have returned to normal, except for the distribution of lymphocyte subpopulations. Furthermore, all indicators of gut-associated lymphoid tissue, except for mesenteric lymph nodes lymphocyte count, had returned to normal levels on 21st day.

Conclusion

In conclusion, our data showed the injuries of spleen and intestinal immune system induced by 2 Gy ⁶⁰Co γ ray whole-body irradiation. These findings may provide the bases for further radiation protection in the immunity.

Keywords:

• Ionizing radiation
• spleen injury
• intestinal immune injury

Ethics approval and consent to participate

The animal study was reviewed and approved by Ethics Committee of Beijing University of Chinese medicine (permit NO. BUCM-4-2017041506-2006).

Consent for publication

The authors all agreed for publication of this paper.

Author contributions

AW and SH designed the study. AW, ZS, LW, YW, XC, CH preformed the experiment. WX, QF, SZ, YG and TW provided experimental guidance. XZ participated in data analysis. AW, ZS and SH contributed to writing assistance and reading the manuscript. All authors contributed to the article and approved the submitted version.

Disclosure statement

The authors declare that they have no competing interests in this paper.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [nos 12075035 and 11675027], Longitudinal Development Project of Beijing University of Chinese Medicine [no. 2019-ZXFZJJ-009] and Key Program of Beijing University of Chinese Medicine [no. 2020-JYB-ZDGG-008].

Notes on contributors

An Wang

An Wang is a PhD student in the School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China.

Zhongyu Shi

Zhongyu Shi is a PhD student in the School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China.

Lei Wang

Lei Wang is a PhD student in the School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China.

Yan Wang

Yan Wang is a MD student in the School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China.

Xiaoying Chen

Xiaoying Chen is a PhD student in the School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China.

Changhao He

Changhao He is a MD student in the School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China.

Xiaomeng Zhang

Xiaomeng Zhang is a PhD student in the School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China.

Wenhui Xu

Wenhui Xu, PhD, is an Associate Investigator of Beijing Research Institute of Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China.

Qian Fu

Qian Fu, MD, is a Research Associate in the School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China.

Tieshan Wang

Tieshan Wang is a Lab Assistant of Beijing Research Institute of Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China.

Shujing Zhang

Shujing Zhang, PhD, is a Senior Experimentalist in the School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China.

Yushan Gao

Yushan Gao, MD, is a Research Associate in the School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China.

Sumin Hu

Sumin Hu, PhD, is a Professor in the School of Traditional Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China.