The present application relates to composition of matter, processes and use of composition of matter relating to flavivirus proteins, peptides, and epitopes, for example, for therapeutic or preventative vaccination against one or more flavivirus serotypes or species, and/or for inducing, enhancing, or sustaining an immune response against at least one flavivirus serotype or species. The flavivirus may be for example the Zika and/or Dengue virus.

Embodiments herein report compositions, uses and manufacturing of dengue virus constructs and live attenuated dengue viruses. Some embodiments concern a composition that includes, but is not limited to, a tetravalent dengue virus composition. In certain embodiments, compositions can include constructs of one or more serotypes of dengue virus, such as dengue-1 (DEN-1) virus, dengue-2 (DEN-2) virus, dengue-3 (DEN-3) or dengue-4 (DEN-4) virus constructs. In other embodiments, constructs disclosed herein can be combined in a composition to generate a vaccine against more one or more dengue virus constructs that may or may not be subsequently passaged in mammalian cells.

Embodiments herein report compositions, uses and manufacturing of dengue virus constructs and live attenuated dengue viruses. Some embodiments concern a composition that includes, but is not limited to, a tetravalent dengue virus composition. In certain embodiments, compositions can include constructs of one or more serotypes of dengue virus, such as dengue-1 (DEN-1) virus, dengue-2 (DEN-2) virus, dengue-3 (DEN-3) or dengue-4 (DEN-4) virus constructs. In other embodiments, constructs disclosed herein can be combined in a composition to generate a vaccine against more one or more dengue virus constructs that may or may not be subsequently passaged in mammalian cells.

The invention provides a vaccine composition comprising a flavivirus peptide comprising one or more CD8+ T cell C1 epitopes, wherein the peptide is attached to a nanoparticle.

The present invention relates to a lentiviral vector-based Japanese encephalitis (JE) immunogenic composition. The present invention is directed to a recombinant lentiviral vector expressing the precursor of membrane (prM) and the envelope (E) protein, in particular glycoprotein of a Japanese encephalitis virus (JEV) or immunogenic fragments thereof. The present invention also provides cells expressing the lentiviral vector, uses and methods to prevent a JEV infection in a mammalian host, especially in a human or an animal host, in particular a pig or a piglet, preferably a domestic pig or a domestic piglet.

Described herein are improved purification methods for virus vaccines and compositions. Also described are Zika, Chikungunya, dengue and yellow fever vaccines and methods of producing and administering said vaccines to subjects in need thereof.

A Dengue virus Envelope Dimer Epitope (EDE) wherein the EDE: c) spans the polypeptides of a Dengue virus Envelope polypeptide dimer; and/or d) is presented on a dimer of Envelope proteins; and/or c) is formed from consecutive or non-consecutive residues of the envelope polypeptide dimer, wherein the dimer is a homodimer or heterodimer of native and/or mutant envelope polypeptides, from any one or two of DENV-1, DENV-2, DENV-3 and DENV-4. The EDE may be a stabilized recombinant dengue virus envelope glycoprotein E ectodomain (sE) dimer, wherein the dimer is: covalently stabilized with at least one disulphide inter-chain bond between the two sE monomers, and/or covalently stabilized with at least one sulfhydryl-reactive crosslinker between the two sE monomers, and/or covalently stabilized by linking the two sE monomers through modified sugars; and/or, covalently stabilised by being formed as a single polypeptide chain, optionally with a linker region, optionally a Glycine Serine rich linker region, separating the sE sequences, and/or non-covalently stabilized by substituting at least one amino acid residue in the amino acid sequence of at least one sE monomer with at least one bulky side chain amino acid, at the dimer interface or in domain 1 (D1)/domain 3 (D3) linker of each monomer. A compound, for example an antibody or antibody fragment that can neutralise more than one Dengue virus serotype, for example an antibody that can bind to an EDE of the invention.

Aspects of the disclosure relate to nucleic acid vaccines. The vaccines include one or more RNA polynucleotides having an open reading frame encoding one or more Chikungunya antigen(s), one or more Zika virus antigens, and one or more Dengue antigens. Methods for preparing and using such vaccines are also described.

Chimeric flaviviruses that include non-coding regions, non-structural proteins, a capsid (C) protein and a portion of a premembrane (prM) signal sequence from an attenuated or wild-type dengue serotype 2 virus (DENV-2), and a portion of a prM signal sequence, a prM protein and at least a portion of an envelope (E) protein from a Zika virus (ZIKV) are described. Also described are immunogenic compositions and methods for eliciting an immune response in a subject, such as an immune response directed against ZIKV.

Dengue Fever (DF) and Dengue Hemorrhagic Fever (DHF) are significant global public health problems and understanding the overall immune response to infection will contribute to appropriate management of the disease and its potentially severe complications. Live attenuated and subunit vaccine candidates, which are under clinical evaluation, induce primarily an antibody response to the virus and minimal cross-reactive T cell responses. Currently, there are no available tools to assess protective T cell responses during infection or post vaccination. Herein, we report novel, naturally processed and presented MHC class I restricted epitopes, a subset of which binds to and activates T cells in both an HLA-A2 and HLA-A24 restricted manner. We show that epitope specific T cells can be activated in vivo in transgenic mice and in vitro in seropositive and seronegative individuals and that these T cells are functional, recognizing peptide pulsed and dengue virus infected cells in a pro-inflammatory and cytotoxic manner. These epitopes have potential as new informational and diagnostic tools to characterize T cell immunity in Dengue virus (DV) infection, and may serve as a universal vaccine candidate complementary to current vaccines in trial.