Aim: To explore the mechanisms underlying the T cell anergy induced by immunotherapy for the treatment of allergic asthma.
Methods: Murine model of allergic asthma was established through the OVA sensitization and challenge. Three injections of 1 mg OVA were used as immunotherapy. Pathological examination of lung tissues, cell count and differential count of bronchoalveolar lavage fluid (BALF), determination of serum OVA-specific IgE, and measurement of IL-2 and IL-4 production and proliferation of the splenic T cells to OVA were preformed to analyze the effect of immunotherapy on asthma. The expression of CTLA-4 on splenic T cells was detected by FACS.
Results: Asthma-specific immunotherapy could alleviate lung inflammation, decrease eosinophil infiltration in BALF (P<0.01) and serum OVA-specific IgE, inhibit the production of IL-2 and IL-4 and the proliferation of splenic T cells to OVA (P<0.01), and up-regulate the expression of CTLA-4 on splenic T cells.
Conclusion: The up-regulation of CTLA-4 expression on T cells may be involved in the T cell anergy induced by asthma-specific immunotherapy.