The effect of magnetic nanoparticles of Fe₃O₄ on immune function in normal ICR mice

Abstract

We investigated the effect of magnetic nanoparticles of Fe₃O₄ (Fe₃O₄-MNPs) on the mice immune system. Imprinting control region (ICR) mice were assigned randomly into four groups and treated with normal saline or low, medium, or high doses of Fe₃O₄-MNPs, respectively. After intravenous administration of Fe₃O₄-MNPs for 72 hours, the peripheral T cells and the induction of primary immune responses in mice were investigated by flow cytometry and determined using enzyme-linked immunosorbent assay, respectively. The results showed that the ratio of spleen to body weight was not different between the experimental groups and control group (P > 0.05). The lymphocyte transformation rates in the suspension of spleen were higher in low-dose group than those in the control group (P < 0.05), while the proliferation of splenocytes was low in the medium and high groups when compared to the control group (P < 0.05). In peripheral blood, both the proportions of subset CD4⁺ and CD8⁺ T lymphocytes in the low-dose group were higher than those in the control group, whereas there was no difference in the number of CD4⁺ T cells between the medium- and low-dose groups. Interestingly, the Fe₃O₄-MNPs enhanced the production of interleukin-2 (IL-2), interferon-γ, and IL-10 but did not affect the production of IL-4 in peripheral blood. It is concluded that Fe₃O₄-MNPs could influence immune functions of normal ICR mice in a dose-dependent manner.

Keywords:

• magnetic nanoparticle of Fe₃O₄
• immune function
• splenocyte proliferation
• cytokine

Acknowledgments

This work was supported by 973 National Key Fundamental Research Project of China (No. 2006CB933205), 863 Project of People’s Republic of China (No. 2007AA022007), National Nature Science Foundation of People’s Republic of China (No. 30740062, 30872970), and Special-Purpose Science Research Foundation for High School (No. 20070286042).

Disclosure

The authors confirm no conflicts of interest in this work.