Influenza virus recombinant proteins
Inventors
Khurana, Surender • Golding, Hana
Assignees
US Department of Health and Human Services • Office of Technology Transfer
Publication Number
US-9896484-B2
Publication Date
2018-02-20
Expiration Date
2030-11-02
Interested in licensing this patent?
MTEC can help explore whether this patent might be available for licensing for your application.
Abstract
The present invention includes influenza Hemagglutinin protein fragments that fold properly when expressed in bacteria.
Core Innovation
The invention provides isolated influenza Hemagglutinin protein fragments, specifically portions comprising at least influenza Hemagglutinin-1 (HA-1) domain sequences that fold properly when expressed in bacteria, without comprising the Hemagglutinin-2 (HA-2) domain and/or the transmembrane domain. The invention encompasses polypeptides that maintain proper folding and functionality, including trimer and oligomer formation, receptor binding, and hemagglutination abilities, which are important for vaccine and diagnostic uses.
The problem addressed is the difficulty and time-consuming nature of producing properly folded hemagglutinin proteins, particularly trimeric functional forms, using conventional methods relying on chicken eggs and mammalian or insect cells. Influenza viruses mutate frequently, requiring annual vaccine reformulation, and the existing production methods are slow and have scalability limitations. Expressing full-length hemagglutinin proteins in bacteria has previously failed to produce properly folded and functional proteins due to lack of glycosylation and folding challenges.
The inventors discovered that expression of truncated hemagglutinin proteins comprising only the HA-1 domain in bacteria followed by controlled redox refolding results in properly folded proteins exhibiting functional trimeric and oligomeric structures. These bacterially expressed HA-1 fragments bind conformation-sensitive influenza neutralizing antibodies, red blood cells in hemagglutination assays, and influenza receptors such as sialic acid, making them suitable for vaccines, diagnostics, and potency assays.
Claims Coverage
The patent contains multiple independent claims focused on recombinant vectors encoding influenza hemagglutinin polypeptides and their features.
Recombinant vector encoding a hemagglutinin-1 (HA-1) domain lacking HA-2 and transmembrane domains
A recombinant vector comprising a polynucleotide encoding an influenza polypeptide that includes at least a portion of the influenza Hemagglutinin-1 (HA-1) domain but lacks the Hemagglutinin-2 (HA-2) domain or both HA-2 and transmembrane domains.
Specific HA-1 sequence identity and conserved amino acids for oligomerization
The HA-1 portion consists of an influenza amino acid sequence at least 80% identical to positions 1-259 or at least 90% identical to positions 1-320 of SEQ ID NOs 1-7, comprising conserved residues including isoleucine or leucine at position 3, cysteine at position 4, isoleucine, leucine, or valine at position 5, and glycine at position 6 corresponding to SEQ ID NO: 2.
Generation of neutralizing antibodies by administration of oligomeric polypeptides
Administration of oligomers of the hemagglutinin-1 polypeptide to an animal generates neutralizing antibodies against influenza virus.
Polypeptide binding to conformation-sensitive influenza neutralizing antibodies
The polypeptide encoded by the vector binds conformation-sensitive influenza neutralizing antibodies, indicating proper folding and antigenicity.
The claims focus on recombinant vectors encoding HA-1 domain polypeptides lacking HA-2 and transmembrane regions, with defined sequence identities and conserved residues essential for oligomer formation and functional activity, enabling generation of neutralizing antibodies and binding of conformation-dependent neutralizing antibodies.
Stated Advantages
Enables economical and rapid production of properly folded trimeric HA-1 proteins in bacterial systems, reducing manufacturing timelines by several months compared to traditional egg-based influenza vaccine production.
Bacterially expressed HA-1 proteins generate strong neutralizing antibody responses and can serve as reagents for potency assays such as Single Radial Immunodiffusion (SRID).
Proper folding and oligomerization of HA-1 fragments mimic native viral hemagglutinin structures, allowing effective binding to influenza receptors and neutralizing antibodies, enhancing vaccine efficacy.
The method supports generation of broadly cross-neutralizing antibodies and protection against diverse influenza strains in animal models, indicating utility in effective vaccine design.
Documented Applications
Use as recombinant influenza vaccines comprising bacterially expressed HA-1 domain polypeptides to induce immune responses in animals including humans and ferrets.
Production of reagents for vaccine potency testing, including generation of single radial immunodiffusion (SRID) antisera and reference antigens.
Assays for detecting influenza-specific antibodies in biological samples using bacterially expressed HA-1 proteins.
Rapid production of influenza vaccine components enabling response to pandemic outbreaks by overcoming egg-based production bottlenecks.
Interested in licensing this patent?