The present invention provides, among other things, a novel and improved method for generating “mosaic” influenza antigenic polypeptides including hemagglutinin (HA) and neuraminidase (NA) polypeptides based on unique combination of epitope patterns that maximize exposure to epitopes present across multiple HA or NA sequences and therefore improved influenza strain coverage. In particular, the present invention provides engineered H1N1 influenza hemagglutinin (HA) polypeptides that are comprised of novel combinations of protective epitopes and antigenic regions from multiple H1N1 viral strains. Such engineered HA polypeptides have improved properties over HA polypeptides developed through conventional approaches that rely on consensus alignments of viral sequences.

A synthetic hemagglutinin (sHA) which represents the highest degree of conservation in the HA sequences of all Influenza B viruses (IVB) based on comprehensive bioinformatics analyses was cloned into an adenoviral vector. The recombinant adenovirus carrying the sHA gene was then delivered intransallyintranasally into DAB/2 mice. The animals were challenged with 5xLD50 influenza B viruses. We have found that the synthetic HA vaccines afford 100% protection against lethal challenge whereas 50% mice died in the control group. Furthermore, no virus was found in the lung of the vaccinated group while significant lung viruses were found in all mice of the controlled group. Consistent with the survival data and virus titre, severe pneumonia was found in all mice of the control group while no pathologic observation was made in animals receiving the vaccines.

Disclosed herein are multivalent nanoparticle vaccine compositions suitable for use in influenza vaccines. The nanoparticles include effective amounts of influenza glycoproteins that provide increased immune responses compared to a commercially available influenza vaccine composition. The present disclosure also provides vaccine formulation strategies that are cost effective and are convenient for clinical use. Methods of administering the nanoparticle vaccine compositions to a subject are also disclosed.

Disclosed herein are multivalent nanoparticle vaccine compositions suitable for use in influenza vaccines. The nanoparticles include effective amounts of influenza glycoproteins that provide increased immune responses compared to a commercially available influenza vaccine composition. The present disclosure also provides vaccine formulation strategies that are cost effective and are convenient for clinical use. Methods of administering the nanoparticle vaccine compositions to a subject are also disclosed.

Provided herein are chimeric hemagglutinin (HA) polypeptides and uses thereof for inducing an immune response (e.g., an antibody response) against influenza virus. Also provided herein are methods of generating antibodies to the chimeric HA polypeptides in a subject.

Compositions and methods for the treatment of viral infections include conjugates containing inhibitors of viral neuraminidase (e.g., zanamivir, peramivir, or analogs thereof) linked to an Fc monomer, an Fc domain, and Fc-binding peptide, an albumin protein, or albumin-binding peptide. In particular, conjugates can be used in the treatment of viral infections (e.g., influenza viral infections).

Disclosed herein are methods of forming compounds and exemplary stable compounds in the nature of a conjugated compound at refrigerated or room temperature, which in some embodiments comprises an antigen and virus particle mixed in a conjugation reaction to form a conjugate mixture, such that the conditions and steps of forming these products allow for use of the conjugate mixture as a vaccine, including but not limited to use as a vaccine against various pathogens including for treatment of diseases caused by novel coronaviruses (including SARS-COV 2).

The present specification discloses recombinant nucleic acid constructs encoding an immunogenic multiepitope polypeptide comprising two or more polypeptides, recombinant nucleic acid constructs encoding at least two epitopes from two or more internal proteins of influenza virus, compositions comprising such recombinant nucleic acid constructs and methods of eliciting a T cell immune response against an influenza virus in a vertebrate using such recombinant nucleic acid constructs and compositions.

Provided herein are chimeric hemagglutinin (HA) polypeptides and uses thereof for inducing an immune response (e.g., an antibody response) against influenza virus. Also provided herein are methods of generating antibodies to the chimeric HA polypeptides in a subject.

A synthetic hemagglutinin (sHA) which represents the highest degree of conservation in the HA sequences of all Influenza B viruses (IVB) based on comprehensive bioinformatics analyses was cloned into an adenoviral vector. The recombinant adenovirus carrying the sHA gene was then delivered intransallyintranasally into DAB/2 mice. The animals were challenged with 5xLD50 influenza B viruses. We have found that the synthetic HA vaccines afford 100% protection against lethal challenge whereas 50% mice died in the control group. Furthermore, no virus was found in the lung of the vaccinated group while significant lung viruses were found in all mice of the controlled group. Consistent with the survival data and virus titre, severe pneumonia was found in all mice of the control group while no pathologic observation was made in animals receiving the vaccines.