Size-variable strain-specific protective antigen for Potomac horse fever

Abstract

An isolated and purified antigen which is expressed by a wild-type E. risticii strain and is specific to the stain. The present invention also relates to nucleic acid constructs which encode the antigen, expression vectors, transformed host cells, and methods for producing the antigen.

1 - 27 . (canceled) 
     
     
         28 . A vaccine comprising an immunogenically effective amount of an isolated and purified protein antigen having at least one amino acid sequence selected from the group consisting of SEQ ID NO:4, SEQ ID NO:6 and SEQ ID NO:8, and a pharmaceutically acceptable carrier or diluent. 
     
     
         29 . The vaccine of  claim 28 , wherein the amino acid sequence is SEQ ID NO: 4. 
     
     
         30 . The vaccine of  claim 28 , wherein the amino acid sequence of SEQ ID NO: 6. 
     
     
         31 . The vaccine of  claim 28 , wherein the amino acid sequence is SEQ ID NO: 8. 
     
     
         32 . A vaccine comprising an immunogenically effective amount of an isolated and purified protein antigen encoded by at least one nucleic acid sequence selected from the group consisting of SEQ ID NO:3, SEQ ID NO: 5 and SEQ ID NO:7. 
     
     
         33 . The vaccine of  claim 32 , wherein the nucleic acid sequence is SEQ ID NO: 3. 
     
     
         34 . The vaccine of  claim 32 , wherein the nucleic acid sequence is SEQ ID NO: 5. 
     
     
         35 . The vaccine of  claim 32 , wherein the nucleic acid sequence is SEQ ID NO: 7.