T cell vaccination eliminates antigen-specific T cells and prevents antigen-induced eosinophil recruitment into the...

Asthma is characterized by airway inflammation with prominent eosinophil infiltrates. In a murine model of asthma, antigen-induced eosinophil recruitment into the airways of sensitized mice is mediated by CD4+ T cells and their cytokines, especially IL-5. In the present study, using ovalbumin-specific T cell receptor transgenic mice, we found that T cell vaccination, which was the administration of preactivated and attenuated antigen-specific T cells by the intraperitoneal route, prevented antigen-induced eosinophil recruitment into the airways. This effect was antigen-specific because ovalbumin-specific T cell vaccination did not affect BSA-induced eosinophil recruitment into the airways. We also found that antigen-specific IgE production as well as antigen-induced proliferation and cytokine production of splenocytes were diminished by T cell vaccination. Moreover, flow-cytometric analyses revealed that T cell vaccination eliminated antigen-specific T cells in the periphery. Together, these results indicate that T cell vaccination prevents antigen-induced eosinophil recruitment into the airways presumably by eliminating antigen-specific T cells.