Hepatitis E virus vaccine and method

Abstract

Antigen and antibody vaccine composition effective in preventing hepatitis E virus (HEV) infection are disclosed. The antigen composition includes a peptide corresponding to a carboxyl terminal end region of the capsid protein encoded by the second open reading frame 2 of the HEV genome. The composition is effective in preventing HEV infection after vaccination. The antibody composition contains an antibody effective to block HEV infection of human primary hepatocytes in culture.

It is claimed:  
     
         1 . A vaccine composition used in immunizing an individual against hepatitis E virus (HEV) comprising, in a pharmacologically acceptable carrier, 
 a peptide containing the C-terminal 42 amino acids of the capsid protein encoded by the second open reading frame of the HEV genome.    
     
     
         2 . The composition of  claim 1 , wherein the peptide includes the amino acid sequence identified by one of the following sequences: 
 (i) Sequence ID No. 13    (ii) Sequence ID No. 14, and    (iii) internally consistent variations between Sequence ID Nos. 13 and 14.    
     
     
         3 . The composition of  claim 1 , wherein the peptide includes the amino acid sequence identified by one of the following sequences: 
 (i) Sequence ID No. 15    (ii) Sequence ID No. 16, and    (iii) internally consistent variations between Sequence ID Nos. 15 and 16.    
     
     
         4 . The composition of  claim 1 , wherein the peptide includes the amino acid sequence identified by one of the following sequences: 
 (i) Sequence ID No. 17    (ii) Sequence ID No. 18, and    (iii) internally consistent variations between Sequence ID Nos. 17 and 18.    
     
     
         5 . The composition of  claim 1 , wherein the peptide includes the amino acid sequence identified by one of the following sequences: 
 (i) Sequence ID No. 19    (ii) Sequence ID No. 20, and    (iii) internally consistent variations between Sequence ID Nos. 19 and 20.    
     
     
         6 . The composition of  claim 1 , wherein the peptide includes the amino acid sequence identified by one of the following sequences: 
 (i) Sequence ID No. 21    (ii) Sequence ID No. 22, and    (iii) internally consistent variations between Sequence ID Nos. 21 and 22.    
     
     
         7 . The composition of  claim 1 , wherein the peptide antigen is covalently coupled to a carrier protein.  
     
     
         8 . A method of inhibiting infection of an individual by hepatitis E virus, comprising 
 administering to the subject, by intramuscular injection, the vaccine composition of  claim 1 .    
     
     
         9 . The method of  claim 7 , wherein the peptide in the vaccine composition includes the amino acid sequence identified by one of the following sequences: 
 (i) Sequence ID No. 13    (ii) Sequence ID No. 14,    (iii) internally consistent variations between Sequence ID Nos. 13 and 14,    (iv) Sequence ID No. 15    (v) Sequence ID No. 16,    (vi) internally consistent variations between Sequence ID Nos. 15 and 16,    (vii) Sequence ID No. 17    (viii) Sequence ID No. 18,    (ix) internally consistent variations between Sequence ID Nos. 17 and 18,    (x) Sequence ID No. 19    (xi) Sequence ID No. 20, and    (xii) Internally consistent variations between Sequence ID Nos. 19 and 20,    (xiii) Sequence ID No. 21    (xiv) Sequence ID No. 22, and    (xv) Internally consistent variations between Sequence ID Nos. 21 and 22.    
     
     
         10 . The method of  claim 9 , wherein the peptide in the vaccine composition includes the amino acid sequence identified by one of the following sequences: 
 (vii) Sequence ID No. 17    (viii) Sequence ID No. 18, and    (ix) internally consistent variations between Sequence ID Nos. 17 and 18.    
     
     
         11 . The method of  claim 10 , wherein the peptide in the vaccine includes the amino acid sequence identified by Sequence ID No. 17.  
     
     
         12 . A vaccine composition containing antibodies capable of neutralizing hepatitis E virus (HEV) infection, as evidenced by the ability of the composition to block HEV infection of primary human hepatocyte cells in culture.  
     
     
         13 . The vaccine composition of  claim 12 , which contains an antibody which is immunoreactive with a peptide containing one of the sequences: 
 (i) Sequence ID No. 13    (ii) Sequence ID No. 14,    (iii) internally consistent variations between Sequence ID Nos. 13 and 14,    (iv) Sequence ID No. 15    (v) Sequence ID No. 16,    (vi) internally consistent variations between Sequence ID Nos. 15 and 16,    (vii) Sequence ID No. 17    (viii) Sequence ID No. 18,    (ix) internally consistent variations between Sequence ID Nos. 17 and 18,    (x) Sequence ID No. 19    (xi) Sequence ID No. 20, and    (xii) Internally consistent variations between Sequence ID Nos. 19 and 20,    (xiii) Sequence ID No. 21    (xiv) Sequence ID No. 22, and    (xv) Internally consistent variations between Sequence ID Nos. 21 and 22.    
     
     
         14 . The composition of  claim 13 , wherein the antibody in the composition is immunoreactive with a peptide containing the sequence identified by 
 (i) Sequence ID No. 13    (ii) Sequence ID No. 14, or    (iii) internally consistent variations between Sequence ID Nos. 13 and 14, and    (iv) Sequence ID No. 15    (v) Sequence ID No. 16, or    (vi) internally consistent variations between Sequence ID Nos. 15 and 16,    Sequence ID No. 13.    
     
     
         15 . A method of preventing or treating HEV infection in an individual, comprising 
 administering to the subject, by parenteral injection, the vaccine composition of  claim 13 .    
     
     
         16 . The method of  claim 15 , wherein the antibody composition includes an antibody which is immunoreactive against a peptide having the amino acid sequence identified by one of the following sequences: 
 (vii) Sequence ID No. 17    (viii) Sequence ID No. 18, and    (ix) internally consistent variations between Sequence ID Nos. 17 and 18.    
     
     
         17 . The method of  claim 16 , wherein the antibody composition contains an antibody which is immunoreactive with a peptide containing one of the sequences: 
 (i) Sequence ID No. 13    (ii) Sequence ID No. 14, or    (iii) internally consistent variations between Sequence ID Nos. 13 and 14, and    (vii) Sequence ID No. 15    (viii) Sequence ID No. 16,    (ix) internally consistent variations between Sequence ID Nos. 15 and 16.    
     
     
         18 . The method of 17, wherein the antibody in the composition is immunoreactive with a peptide containing the sequence identified by Sequence ID No. 15.  
     
     
         19 . The method of  claim 15 , wherein the antibody composition includes an antibody which is immunoreactive against a peptide having the amino acid sequence identified by one of the following sequences: 
 (xiii) Sequence ID No. 21    (xiv) Sequence ID No. 22, and    (xv) Internally consistent variations between Sequence ID Nos. 21 and 22.