The present disclosure provides a method of inducing a cross-protective immune response in a subject against a pathogen, such as influenza, comprising administering a first unique pathogen antigen to the subject； and administering a second unique pathogen antigen 3-52 weeks after a)； wherein the second unique pathogen antigen and the first unique pathogen antigen are immunologically distinct but share conserved sites that are not normally immunogenic for antibodies. Also disclosed herein are assays for detecting cross-protective antibodies, methods of generating novel cross-protective antibodies. Further provided are novel antibodies against influenza.
