The present invention relates to methods of modulating an immune response in a subject by using a binding protein (e.g., an antibody or an antigen-binding portion of an antibody) to mask or alter an epitope on an antigen that is administered to the subject. Such methods are useful for inducing an immune response (e.g., production of an antibody) in the subject to a non-immunodominant epitope on the antigen. The invention also encompasses an antigen-binding protein complex comprising at least one binding protein bound to at least one immunodominant epitope on an antigen.