Antisense oligonucleotides-induced local blockade of T-bet expression leads to airway inflammation in rats1

Abstract

To explore whether local blockade of T-box expressed in T cells (T-bet) expression in the lungs could lead to airway inflammation. Twenty-four rats were randomly divided into 4 groups: saline group, ovalbumin (OVA)-sensitized group, nonsense group, and the antisense group. The OVA-sensitized rats were sensitized and challenged with OVA, and the rats in the nonsense and antisense groups were subjected to an aerosol delivery of the nonsense and antisense oligonucleotides (AS-ODN) of T-bet (0.1%, w/v). The levels of interferon-gamma (IFN-gamma), interleukin-4 (IL-4), and IL-5 in the bronchoalveolar lavage fluid (BALF) were detected by ELISA, and the mRNA and the protein expression of T-bet and GATA-3 genes were examined by in situ hybridization and Western blot analysis, respectively. The expression of T-bet mRNA and protein in the lungs of the rats in the antisense group were inhibited effectively. The lungs of the rats in the antisense and OVA-sensitized groups showed eosinophil and lymphocyte inflammatory infiltration, and eosinophilia located predominantly around the airways. The number of GATA-3 mRNA-positive cells and the level of GATA-3 protein in the lungs of the rats in the antisense and the OVA-sensitized groups significantly increased. The level of IL-4 and IL-5 in the BALF in the antisense and OVA-sensitized groups were elevated, but the level of IFN-gamma decreased markedly. Antisense ODN-induced local blockade of T-bet expression leads to airway inflammation with a selective alteration in patterns of cytokine expression and recruitment of eosinophil cells similar to that in the OVA-sensitized animals.