The present inventors have discovered that in living organisms that have received an antigen-binding molecule containing an antigen-binding domain whose binding activity to an antigen changes depending on ion concentration conditions and containing an FcRn-binding domain having FcRn-binding activity in a neutral pH range, immune responses to the antigen are induced. Furthermore, the present inventors have discovered that in living organisms that have received an antigen-binding molecule containing an antigen-binding domain whose binding activity to an antigen changes depending on ion concentration conditions and containing an FcRn-binding domain having FcRn-binding activity in a neutral pH range, immune responses to the antigen are induced, and also the antigen-binding molecule has cytotoxicity or antiproliferative action against cancer cells, foreign biological species, or such that express the antigen to which the antigen-binding molecule binds.
