The present invention provides a complex of an antigen and IgE binding to the antigen, a composition including an antigen and IgE binding to the antigen, and a method of using the complex or the composition. With the present invention, it is possible to induce naive T cells to develop into Th2 cells. Moreover, the present invention clarified a working mechanism of a Th2-type immune response, particularly a production mechanism of early IL-4. With use of the present invention, it is possible to provide a technique of treating and preventing Th2-type diseases.
