The present disclosure provides compositions and methods for detecting the presence of neutralizing antibodies in a sample. Unlike conventional assays, the methods provided herein do not require the use of live virus or virus pseudoparticles to identify neutralizing antibodies.

Disclosed herein are nucleic acid molecules encoding a SARS-CoV-2 spike antigen, SARS-CoV-2 spike antigens, immunogenic compositions, and vaccines and their use in inducing immune responses and protecting against or treating a Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) infection in a subject.

Timely development of vaccines and antiviral drugs is critical to control the COVID-19 pandemic. Current methods for quantifying vaccine-induced neutralizing antibodies involve the use of pseudoviruses, such as the SARS-CoV-2 spike protein (S) pseudotyped lentivirus. However, these pseudoviruses contain structural proteins foreign to SARS-CoV-2, and require days to infect and express reporter genes. Here, the present application discloses composition and methodology for making and using a new hybrid alphavirus-SARS-CoV-2 (Ha-CoV-2) particle for rapid and accurate quantification of neutralization antibodies and viral variants.

Disclosed herein are nucleic acid molecules encoding a SARS-CoV-2 spike antigen, SARS-CoV-2 spike antigens, immunogenic compositions, and vaccines and their use in inducing immune responses and protecting against or treating a Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) infection in a subject.

The present disclosure provides compositions and methods for detecting the presence of neutralizing antibodies in a sample. Unlike conventional assays, the methods provided herein do not require the use of live virus or virus pseudoparticles to identify neutralizing antibodies.

Timely development of vaccines and antiviral drugs is critical to control the COVID-19 pandemic. Current methods for quantifying vaccine-induced neutralizing antibodies involve the use of pseudoviruses, such as the SARS-CoV-2 spike protein (S) pseudotyped lentivirus. However, these pseudoviruses contain structural proteins foreign to SARS-CoV-2, and require days to infect and express reporter genes. Here, the present application discloses composition and methodology for making and using a new hybrid alphavirus-SARS-CoV-2 (Ha-CoV-2) particle for rapid and accurate quantification of neutralization antibodies and viral variants.

The present disclosure provides compositions and methods for detecting the presence of neutralizing antibodies in a sample. Unlike conventional assays, the methods provided herein do not require the use of live virus or virus pseudoparticles to identify neutralizing antibodies.

Disclosed herein are nucleic acid molecules encoding a SARS-CoV-2 spike antigen, SARS-CoV-2 spike antigens, immunogenic compositions, and vaccines and their use in inducing immune responses and protecting against or treating a Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) infection in a subject.

In aspects, the invention provides novel compositions and methods for dominant inhibition of viral infection.

The present invention relates to an expression vector that encodes all or a portion of replicon proteins from a positive stranded virus, wherein expression of the replicon proteins is under the control of CMV and T7 promoters, and wherein expression of a payload is under the control of a sub-genomic promoter. Also provided are methods of using the vector in therapeutics and vaccines.