Systemic Immune Effects of Titanium Dioxide Nanoparticles after Repeated Intratracheal Instillation in Rat

International Journal of Molecular Sciences

Yanyun Fu¹  Yanqiu Zhang¹  Xuhong Chang²  Yingjian Zhang¹  Shumei Ma¹  Jing Sui¹  Lihong Yin¹  Yuepu Pu¹ 

[1] Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, Jiangsu, China; E-Mails:;Department of Epidemiology and Health Statistics, School of Public Health, Southeast University, Nanjing 210009, Jiangsu, China; E-Mail:

关键词: nano-TiO₂;    systemic immune response;    lymphocyte proliferation;    cytokines;   

DOI  :  10.3390/ijms15046961

来源: mdpi

【 摘 要 】

The potential immune effects of titanium dioxide nanoparticles (nano-TiO₂) are raising concern. Our previous study verified that nano-TiO₂ induce local immune response in lung tissue followed by intratracheal instillation administration. In this study, we aim to evaluate the systemic immune effects of nano-TiO₂. Sprague Dawley rats were treated by intratracheal instillation with nano-TiO₂ at doses of 0.5, 4, and 32 mg/kg body weight, micro-TiO₂ with 32 mg/kg body weight and 0.9% NaCl, respectively. The exposure was conducted twice a week, for four consecutive weeks. Histopathological immune organs from exposed animals showed slight congestion in spleen, generally brown particulate deposition in cervical and axillary lymph node. Furthermore, immune function response was characterized by increased proliferation of T cells and B cells following mitogen stimulation and enhanced natural killer (NK) cell killing activity in spleen, accompanying by increased number of B cells in blood. No significant changes of Th1-type cytokines (IL-2 and INF-γ) and Th2-type cytokines (TNF-α and IL-6) were observed. Intratracheal exposure to nano-TiO₂ may be one of triggers to be responsible for the systemic immune response. Further study is needed to confirm long-lasting lymphocyte responses and the potential mechanisms.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland