The present disclosure is directed to improved virus-like particle (VLP) compositions and vaccines for use in inducing an immune response and/or protective immunity against a Chikungunya virus (CHIKV) infection in a subject, e.g., by inducing a neutralizing antibody response against CHIKV in a subject within 7 days after administration of a single dose of the composition or vaccine.

Provided is a vaccine composition including a recombinant DNA vaccine against a pathogen. The recombinant DNA vaccine includes an expression cassette operably linked to a promoter, and the expression cassette encodes a non-structural protein of a Sindbis virus and an antigenic protein of the pathogen. Also provided is a method of producing a protective immune response against a pathogen in a subject in need thereof by administering the vaccine composition to the subject.

Provided are surprisingly effective methods for inactivating pathogens, and for producing highly immunogenic vaccine compositions containing an inactivated pathogen rendered noninfectious by exposure to a Fenton reagent, or by exposure to a Fenton reagent or a component thereof in combination with a methisazone reagent selected from the group consisting of methisazone, methisazone analogs, functional group(s)/substructure(s) of methisazone, and combinations thereof. The methods efficiently inactivate pathogens, while substantially retaining pathogen antigenicity and/or immunogenicity, and are suitable for inactivating pathogens, or for the preparation of vaccines for a wide variety of pathogens with genomes comprising RNA or DNA, including viruses and bacteria. Also provided are highly immunogenic inactivated vaccine compositions prepared by using any of the disclosed methods, and methods for eliciting an immune response in a subject by administering such vaccine compositions.

The present disclosure relates to methods for transiently activating temperature-sensitive agents in one or more cells, for example by contacting one or more cells with a temperature-sensitive agent and transiently incubating the cells at a permissive temperature for inducing an activity of the temperature-sensitive agent in the cells. Additionally, the present disclosure relates to methods of contacting one or more cells in a subject with a temperature-sensitive agent and then lowering the subject's core body temperature to a permissive temperature for inducing an activity of the temperature-sensitive agent in the cells. The disclosure also relates to methods of contacting one or more cells in a subject with a temperature-sensitive agent, maintaining the subject's surface body temperature at a permissive temperature for inducing an activity of the temperature-sensitive agent in the cells. Further disclosed are methods of treating a subject with a temperature-sensitive therapeutic agent.

The present disclosure relates to methods for transiently activating temperature-sensitive agents in one or more cells, for example by contacting one or more cells with a temperature-sensitive agent and transiently incubating the cells at a permissive temperature for inducing an activity of the temperature-sensitive agent in the cells. Additionally, the present disclosure relates to methods of contacting one or more cells in a subject with a temperature-sensitive agent and then lowering the subject's core body temperature to a permissive temperature for inducing an activity of the temperature-sensitive agent in the cells. The disclosure also relates to methods of contacting one or more cells in a subject with a temperature-sensitive agent, maintaining the subject's surface body temperature at a permissive temperature for inducing an activity of the temperature-sensitive agent in the cells. Further disclosed are methods of treating a subject with a temperature-sensitive therapeutic agent.

Described herein is a method of preventing or treating a disease in a mammalian subject, comprising administering to the subject who is in need thereof an effective dosage of a pharmaceutical composition comprising a virus like particle (VLP) comprising: an alphavirus replicon comprising a recombinant polynucleotide, wherein the polynucleotide comprises a sequence encoding both subunits of a human class II major histocompatibility antigen, a retroviral gag protein, and a fusogenic envelope protein, wherein the VLP does not contain an alphavirus structural protein gene.

The present disclosure includes, among other things, non-natural nucleotides useful as 5′ caps for RNA nucleotides. The present disclosure also includes, among other things, compositions and methods using delivery and vaccine RNA nucleotide compositions that include non-natural nucleotides as 5′ caps.

Nucleic acid immunisation is achieved by delivering RNA encapsulated within a PEGylated liposome. The RNA encodes an immunogen of interest. The PEG has an average molecular mass of between 1 kDa and 3 kDa. Thus the invention provides a liposome having a lipid bilayer encapsulating an aqueous core, wherein: (i) the lipid bilayer comprises at least one lipid which includes a polyethylene glycol moiety, such that polyethylene glycol is present on the liposome's exterior, wherein the average molecular mass of the polyethylene glycol is between 1 kDa and 3 kDa; and (ii) the aqueous core includes a RNA which encodes an immunogen. These liposomes are suitable for in vivo delivery of the RNA to a vertebrate cell and so they are useful as components in pharmaceutical compositions for immunising subjects against various diseases.

Provided herein are polypeptides, polynucleotides, expression vectors, infectious clones, virus particles and immunogenic compositions of recombinant alphaviruses which can be used as vaccines. Also provided are methods for eliciting an immune response against alphavirus infection using the immunogenic composition comprising the alphavirus mutants described herein.

Described herein is a method of preventing or treating a disease in a mammalian subject, comprising administering to the subject who is in need thereof an effective dosage of a pharmaceutical composition comprising a virus like particle (VLP) comprising: an alphavirus replicon comprising a recombinant polynucleotide, wherein the polynucleotide comprises a sequence encoding both subunits of a human class II major histocompatibility antigen, a retroviral gag protein, and a fusogenic envelope protein, wherein the VLP does not contain an alphavirus structural protein gene.