TIM-3 is not essential for development of airway inflammation induced by house dust mite antigens

• DOI: 10.1016/j.alit.2016.04.008
• Publication Date: 2016-05-18T14:07:53Z
• Authors: Yoshihisa Hiraishi; Aya Nambu; Akiko Shibui; Wakako Nakanishi; Sachiko Yamaguchi; Hideaki Morita; Motoyasu Iikura; Andrew N.J. McKenzie; Kenji Matsumoto; Katsuko Sudo; Tatsuya Yamasoba; Takahide Nagase; Susumu Nakae
• Keywords: 0301 basic medicine; Allergy; Mouse; TIM-3; Respiratory Tract Diseases; Article; House dust mite; Mice; 03 medical and health sciences; Th2 Cells; Immunology and Allergy; Animals; Antigens, Dermatophagoides; Hepatitis A Virus Cellular Receptor 2; Inflammation; Mice, Knockout; RC581-607; Immunoglobulin E; Th1 Cells; Asthma; 3. Good health; Disease Models, Animal; Cytokines; Immunologic diseases. Allergy; Bronchoalveolar Lavage Fluid

T cell immunoglobulin domain and mucin domain-containing molecule 3 (TIM-3), which is preferentially expressed on Th1 cells rather than Th2 cells, is considered to be a negative regulator of Th1 cell function. This suggests that TIM-3 indirectly enhances Th2-type immune responses by suppressing Th1 cell function.To investigate TIM-3's possible involvement in Th2-type acute and chronic airway inflammation, wild-type and TIM-3-deficient (TIM-3-/-) mice were sensitized and challenged with a house dust mite (HDM) extract. Airway inflammation and the number of inflammatory cells in bronchoalveolar lavage fluids (BALFs) in the mice were determined by histological analysis and with a hemocytometer, respectively. Expression of mRNA in the lungs was determined by quantitative PCR, while the levels of cytokines in the BALFs and IgE in sera were determined by ELISA.Despite constitutive expression of TIM-3 mRNA in the lungs, the number of eosinophils in bronchoalveolar lavage fluids (BALFs) and the score of pulmonary inflammation were comparable between wild-type and TIM-3-/- mice during both acute and chronic HDM-induced airway inflammation. On the other hand, the number of lymphocytes in the BALFs of TIM-3-/- mice was significantly increased compared with wild-type mice during HDM-induced chronic, but not acute, airway inflammation, while the levels of Th2 cytokines in the BALFs and HDM-specific IgG1 and IgG2a and total IgE in the sera were comparable in both groups.Our findings indicate that, in mice, TIM-3 is not essential for development of HDM-induced acute or chronic allergic airway inflammation, although it appears to be involved in reduced lymphocyte recruitment during HDM-induced chronic allergic airway inflammation.