Abstract: The present invention provides novel methods to identify polypeptide ligands for Toll-like Receptors (TLRs), such as TLR2, TLR4 and TLR5. The method involves the use of phage display technology in an iterative biopanning procedure. The invention also provides polypeptide TLR ligands identified by the methods of the invention. In preferred embodiments, the polypeptide TLR ligands so identified modulate TLR signaling and thereby regulate the Innate Immune Response. The invention also provides vaccines comprising a polypeptide TLR ligand identified by the methods of the invention and an antigen. The invention also provides methods of modulating TLR signaling using the polypeptide TLR ligands and vaccines of the invention.

Abstract: The present invention provides novel polypeptide ligands for Toll-like Receptor 2 (TLR2). Preferrably, the novel polypeptide ligands modulate TLR2 signaling and thereby regulate the Innate Immune Response. The invention also provides vaccines comprising the novel polypeptide TLR2 ligands and an antigen. The invention further provides methods of modulating TLR2 signaling using the polypeptide ligands or vaccines of the invention.

Abstract: Compositions comprise at least a portion of an antigen and at least a portion of a flagellin that lacks a hinge region. Compositions, fusion proteins and polypeptides comprise at least a portion of at least one pathogen-associated molecular pattern and at least a portion of at least one viral protein. The viral protein of the compositions, fusion proteins and polypeptides of the invention are flaviviral proteins, including a West Nile flaviviral protein, a Dengue flaviviral protein, a Langat flaviviral protein, a Kunjin flaviviral protein, a Murray Valley encephalitis flaviviral protein, a Japanese encephalitis flaviviral protein, a Tick-borne encephalitis flaviviral protein, a Yellow fever flaviviral protein and a hepatitis C flaviviral protein. The compositions, fusion proteins and polypeptides are used to stimulate an immune response and protective immunity in a subject.

Abstract: Methods of making and compositions that stimulate a protective immune response in a subject include a portion of a protein from a naturally occurring viral hemagglutinin, wherein the protein portion includes at least a portion of a globular head and at least a portion of at least one secondary structure that causes the globular head to essentially retain its tertiary structure, and wherein the protein portion lacks a membrane fusion domain, a transmembrane domain and a cytoplasmic domain. Compositions can further include a Toll-like Receptor agonist and a carrier protein.

Abstract: Compositions comprise a flagellin component or a Toll-like Receptor agonist component that is at least a portion of a flagellin or a Toll-like Receptor agonist, wherein the flagellin component or Toll-like Receptor agonist component includes at least one cysteine residue and whereby the flagellin component or Toll-like Receptor agonist component activates a Toll-like Receptor 5 or Toll-like Receptor. Compositions comprise a flagellin component that is at least a portion of a flagellin, wherein at least one lysine of the flagellin component has been substituted with at least one arginine, serine and histidine, whereby the flagellin component activates Toll-like Receptor 5. Compositions can further include an antigen, such as an influenza antigen, a flavivirus antigen, a pathogen-related antigen, a bacterial capsular antigen and a carrier protein. The compositions are used to stimulate an immune response and a protective immune response in a subject.