The upregulated expression of OX40/OX40L and their promotion of T cells proliferation in the murine model of asthma

摘要

Objective: To investigate whether the expression of OX40/OX40 ligand (OX40L) was upregulated in a murine model of asthma and their significance in the pathogenesis of asthma. Methods: After an ovalbumin-sensitized/challenged murine model of asthma was established, the expressions of OX40, OX40L in peripheral blood mononuclear cells (PBMCs) and bronchoalveolar lavage fluid (BALF) cell pellets were measured. Then T cell proliferation was analyzed by cell counting kit-8, and the protein levels of OX40 and OX40L in the lungs were determined by immunohistochemistry. The concentrations of IL-4 and IFN-γ in BALF and T cell culture supernatant were evaluated by ELISA. Results: The percentages of CD4+OX40+, CD19+OX40L+, F4/80+OX40L+ in PBMCs and BALF cell pellets were higher in asthma group than in control group (all P0.01). The proliferation capacity of T cells in asthma group was higher than that in control group (P0.05). In asthma group, stimulation of OX40 by anti-OX40 mAb obviously promoted T cell proliferation and secretion of IL-4 and IFN-γ. Immunohistochemistry assay showed that OX40 and OX40L protein levels were higher in asthma group than those in control group (all P0.05). Conclusions: The expressions of OX40 and OX40L were upregulated in the murine asthmatic model. The upregulation of OX40/OX40L signals could induce the proliferation and cytokines secretion of T cells in asthmatic mice, indicating that OX40/OX40L signal was involved in the pathogenesis of asthma.