Abstract: The present invention relates to isolated immunogenic polypeptides and their use. In one aspect, the isolated immunogenic polypeptide includes a scaffold polypeptide having a hairpin loop modified to include one or more epitopes heterologous to the scaffold polypeptide and from an amino acid loop linked by a disulfide bond. The scaffold polypeptide directs self-assembly with two other of the scaffold polypeptides to form a trimeric structure, which constrains the one or more epitopes to a conformation that is (i) substantially similar to one or more native pathogen epitopes in trimeric conformation and (ii) capable of binding an antibody reactive to the one or more native pathogen epitopes in trimeric conformation. Another aspect relates to an isolated immunogenic polypeptide that includes a scaffold polypeptide having a native loop modified to include one or more epitopes heterologous to the scaffold polypeptide and from an amino acid loop linked by a disulfide bond.

Abstract: The present invention relates to isolated immunogenic polypeptides and their use. In one aspect, the isolated immunogenic polypeptide includes a scaffold polypeptide having a hairpin loop modified to include one or more epitopes heterologous to the scaffold polypeptide and from an amino acid loop linked by a disulfide bond. The scaffold polypeptide directs self-assembly with two other of the scaffold polypeptides to form a trimeric structure, which constrains the one or more epitopes to a conformation that is (i) substantially similar to one or more native pathogen epitopes in trimeric conformation and (ii) capable of binding an antibody reactive to the one or more native pathogen epitopes in trimeric conformation. Another aspect relates to an isolated immunogenic polypeptide that includes a scaffold polypeptide having a native loop modified to include one or more epitopes heterologous to the scaffold polypeptide and from an amino acid loop linked by a disulfide bond.