Modulation and the Underlying Mechanism of T Cells in Thymus of Mice by Oral Administration of Sodium Fluoride
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The underlying mechanism of thymic T cell regulation has been a hot topic of research in recent years. Fluoride is toxic at high concentrations and fluoride toxicity to thymic T cells was assessed in our study. To explore T cell responses to excess fluoride, different concentrations of fluoride were uptake by mice for 6 weeks. The expression of genes, including Foxn1, Cbx4, DLL4, and IL-7 gene, associated with the development and differentiation of T cells in thymic epithelial cells(TECs) was lower in the experimental groups than that in the control group. The percentages of CD4+ and CD8+ T cells that decreased with the fluoride administration were confirmed by flow cytometry. The mRNA levels of immunoregulatory cytokines IL-2 and IL-10, which participate in T cell proliferation, also declined in the experimental groups as compared with the control group. Expression of the T cell function-related genes CD2, PTPRC, CD69, and CD101, which are involved in thymic function in mice, decreased with the fluoride administration. Our findings suggest that the administration of high concentrations of fluoride to mice induces a decrease in CD4+ and CD8+ thymus T cells by harming TECs leading to the dysfunction of the thymus by altering the expression of T cell function-related genes and immunoregulatory cytokine production.
KeywordsSodium fluoride Mice Thymus T cells TECs
We thank Dr. Jianhui Wei and Dr. Zhikun Xu for insightful discussions and carefully correcting the paper. This work was supported by the National High Technology Research and Development Program of China (863 Program) (No. 2011AA100303) (http://www.most.gov.cn).
This study was funded by the National High Technology Research and Development Program of China (863 Program) (No. 2011AA100303) (http://www.most.gov.cn). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Conflict of Interest
The authors declare that they have no conflict of interest.
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