Synthetic plasmid dna vaccine expressing a codon-optimized sars-cov-2 spike protein and methods for its use

Abstract

A synthetic DNA vaccine against SARS-CoV-2 infection comprises a codon-optimized coding sequence for optimal mammalian expression of a pSARS2 spike glycoprotein (pSARS2-S). The signal peptide may be replaced with the signal peptide from the human IgG2 heavy chain. Systemic S1-specific IgG antibodies and neutralizing antibodies (nAbs) were significantly induced in mice at 2 weeks-post three injections with 100 μg of the pSARS2-S vaccine via intramuscular (IM) needle injection. IM immunization induced Th1-skewed and long-lasting IgG response in BALB/c mice. Immunogenicity and induction of nAbs were enhanced with a needle-free delivery system, wherein two doses were sufficient to elicit significant levels of systemic S1-specific IgG antibodies and nAbs via IM or intradermal immunization.

We claim: 
     
         1 . A DNA vaccine able to induce an immune response against a SARS-CoV-2 coronavirus, comprising a DNA plasmid encoding a codon-optimized pSARS2 spike glycoprotein (pSARS2-S) as an immunogen from a SARS-CoV-2 coronavirus, wherein the pSARS2-S is codon-optimized for mammalian expression, and wherein the pSARS2-S N-terminal signal peptide is replaced with a signal peptide from a human IgG2 heavy chain. 
     
     
         2 . The DNA vaccine of  claim 1 , wherein DNA sequences encoding the codon-optimized pSARS2-S and encoding the signal peptide from the human IgG2 heavy chain have the nucleotide sequence identity of SEQ ID NO:1. 
     
     
         4 . The DNA vaccine of  claim 1 , wherein the DNA sequences of the signal peptide from the human IgG2 heavy chain encode an amino acid sequence having the identity of SEQ ID NO:2. 
     
     
         4 . The DNA vaccine of  claim 1 , wherein the DNA sequences encoding the signal peptide from the human IgG2 heavy chain have the nucleotide sequence identity of SEQ ID NO:3. 
     
     
         5 . The DNA vaccine of  claim 1 , wherein the DNA sequences encode a protein having the amino acid identity of SEQ ID NO:4. 
     
     
         6 . A DNA vaccine able to induce an immune response to a SARS-CoV-2 coronavirus, wherein the immunogen is encoded by nucleotide sequences having the identity of SEQ ID NO:1. 
     
     
         7 . The DNA vaccine of  claim 6 , wherein the nucleotide sequences encode a protein having the amino acid sequence identity of SEQ ID NO:4. 
     
     
         8 . A method of inducing an immune response to a pSARS2 spike glycoprotein (pSARS2-S) from a SARS-CoV-2 coronavirus in a subject in need thereof, comprising the steps of
 administering to a subject a dose of a pharmaceutical composition comprising a DNA plasmid encoding a codon-optimized pSARS2 spike glycoprotein (pSARS2-S) from a SARS-CoV-2 coronavirus, wherein the pSARS2-S is codon-optimized for mammalian expression, wherein the pSARS2-S N-terminal signal peptide is replaced with a signal peptide from a human IgG2 heavy chain;   allowing a suitable period of time to elapse; and   administering at least one additional dose of the pharmaceutical composition.   
     
     
         9 . The method of  claim 8 , wherein the DNA sequences encoding the codon-optimized pSARS2-S and the signal peptide from the human IgG2 heavy chain have the nucleotide identity of SEQ ID NO:1. 
     
     
         10 . The method of  claim 8 , wherein the pharmaceutical composition is administered intramuscularly or intradermally. 
     
     
         11 . The method of  claim 8 , wherein 10 to 150 μg of the DNA plasmid is administered to the subject in each dose. 
     
     
         12 . The method of  claim 8 , wherein at least 25 μg of the DNA plasmid is administered to the subject in each dose. 
     
     
         13 . The method of  claim 8 , wherein 50 to 100 μg of the DNA plasmid is administered to the subject in each dose. 
     
     
         14 . A method of inducing an immune response to a pSARS2 spike glycoprotein (pSARS2-S) from a SARS-CoV-2 coronavirus in a subject in need thereof, comprising the steps of
 administering to a subject a dose of a pharmaceutical composition comprising a DNA plasmid encoding a codon-optimized pSARS2 spike glycoprotein (pSARS2-S) from a SARS-CoV-2 coronavirus, wherein the pSARS2-S is codon-optimized for mammalian expression, wherein the pSARS2-S N-terminal signal peptide is replaced with a signal peptide from a human IgG2 heavy chain, wherein the pSARS2-S and signal peptide from the human IgG2 heavy chain nucleotide sequences have the identity of SEQ ID NO:1;   allowing a suitable period of time to elapse; and   administering at least one additional dose of the pharmaceutical composition.   
     
     
         15 . The method of  claim 14 , wherein the pharmaceutical composition is administered intramuscularly or intradermally. 
     
     
         16 . The method of  claim 14 , wherein 10 to 150 μg of the DNA plasmid is administered to the subject in each dose. 
     
     
         17 . The method of  claim 14 , wherein at least 25 μg of the DNA plasmid is administered to the subject in each dose. 
     
     
         18 . The method of  claim 14 , wherein 50 to 100 μg of the DNA plasmid is administered to the subject in each dose.