Titanium dioxide nanoparticles exacerbate pneumonia in respiratory syncytial virus (RSV)-infected mice

• DOI: 10.1016/j.etap.2015.02.017
• Publication Date: 2015-03-03T18:44:54Z
• Authors: Seiko Hashiguchi; Hiroki Yoshida; Toshi Akashi; Keiji Komemoto; Tomoyuki Ueda; Yoshiaki Ikarashi; Aki Miyauchi; Katsuhiko Konno; Sayoko Yamanaka; Akihiko Hirose; Masahiko Kurokawa; Wataru Watanabe
• Keywords: Titanium; 0301 basic medicine; Mice, Inbred BALB C; Pneumonia; Respiratory Syncytial Virus Infections; Viral Load; Respiratory Syncytial Viruses; 3. Good health; Viral Proteins; 03 medical and health sciences; Cell Line, Tumor; Animals; Cytokines; Humans; Nanoparticles; Female; Bronchoalveolar Lavage Fluid; Lung

To reveal the effects of TiO2 nanoparticles, used in cosmetics and building materials, on the immune response, a respiratory syncytial virus (RSV) infection mouse model was used. BALB/c mice were exposed once intranasally to TiO2 at 0.5mg/kg and infected intranasally with RSV five days later. The levels of IFN-γ and chemokine CCL5, representative markers of pneumonia, in the bronchoalveolar lavage fluids of RSV-infected mice had increased significantly in TiO2-exposed mice compared with the control on day 5 post-infection, but not in uninfected mice. While pulmonary viral titers were not affected by TiO2 exposure, an increase in the infiltration of lymphocytes into the alveolar septa in lung tissues was observed. Immunohistochemical analysis revealed aggregation of TiO2 nanoparticles near inflammatory cells in the severely affected region. Thus, a single exposure to TiO2 nanoparticles affected the immune system and exacerbated pneumonia in RSV-infected mice.