Disclosed are monoclonal antibodies against Chikungunya virus having enhanced effector function and efficacy, methods of producing them, and methods of treatment of Chikungunya viral infection using the antibodies.

Provided herein, in some embodiments, are compositions of Zika-specific antibodies and antigen-binding fragments thereof and methods of using the antibodies and antigen-binding fragments.

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 nonconsecutive 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 sulfhydrylreactive 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 neutralize more than one Dengue virus serotype, for example an antibody that can bind to an EDE of the invention.

The present disclosure provides neutralising human antibodies that binds to an alphavirus. The antibodies are raised against the chikungunya (CHIKV) virus, and show cross-neutralisation and in vivo protection of other alphaviruses.

Provided is a flavivirus cross neutralizing antibody which has an excellent ability to control infection with suppressed ADE. This is a flavivirus cross neutralizing antibody that specifically binds to domains of E protein of flavivirus and thereby has an ability to control infection with at least two viruses included in the flavivirus. The domains of E protein include a plurality of domains including domain III. The flavivirus includes, for example, Zika virus, dengue virus types 1-4, and Japanese encephalitis virus.

The present disclosure relates to polypeptides that specifically bind to Dengue virus non-structural protein 1, including antibodies and fragments thereof. The antibody or antigen-binding fragment thereof may specifically bind Dengue virus (DENV) serotype 4 and include: a heavy chain variable region that comprises at least one CDR amino acid sequence selected from the group consisting of: SGYNWH, YIHYSGGTNYNPSLKS, RTGTVPFAY, SYVMH, YLNPYNDDTKYNEKFKG, and GPPYALDY. The present disclosure further relates to methods of producing the polypeptides of the present disclosure, methods of diagnosing DENV, and methods of treating a DENV infection.