immunizing composition

Abstract

The present invention is concerned with an antigenic composition comprising at least one antigen that comprises at least one antigenic epitope or antigenic determinant derived from a protein present in one or both of S. equi subsp. equi and subsp. zooepidemicus and use thereof for immunization of non-human mammals against S. equi subsp. equi and/or subsp. zooepidemicus . The present invention also discloses a vaccine composition comprising the aforesaid antigenic composition as immunizing component.

1 . An antigenic composition comprising at least one antigen, wherein said at least one antigen comprises at least part of a protein or polypeptide of  Streptococcus equi  subsp.  equi  or subsp.  zooepidemicus  and said at least part of said protein or polypeptide comprises at least one antigenic epitope or antigenic determinant of  Streptococcus equi , and wherein said protein or polypeptide is selected from the group comprising
 a protein or polypeptide which is designated EAG and has an amino acid sequence as shown in SEQ ID NO: 13;   a protein or polypeptide which is designated IdeE and has an amino acid sequence as shown in SEQ ID NO: 10;   a protein or polypeptide which is designated IdeE2 and has an amino acid sequence as shown in SEQ ID NO: 1;   a protein or polypeptide which is designated Eq5 and has an amino acid sequence as shown in SEQ ID NO: 3;   a protein or polypeptide which is designated Eq8 and has an amino acid sequence as shown in SEQ ID NO: 5;   a protein or polypeptide which is designated IdeZ2 and has an amino acid sequence as shown in SEQ ID NO: 7;   a protein or polypeptide which is designated Eqz5 and has an amino acid sequence as shown in SEQ ID NO: 8; and   a protein or polypeptide which is designated Eqz8 and has an amino acid sequence as shown in SEQ ID NO: 9;   or an analog or fragment thereof, and wherein a composition which comprises EAG comprises at least one further antigen, which is a protein or polypeptide which is selected from the group comprising IdeE, IdeE2, Eq5, Eq8, IdeZ2, Eqz5 and Eqz8.   
     
     
         2 . The antigenic composition of  claim 1 , wherein said at least one protein or polypeptide is selected from the group consisting of IdeE and IdeE2 and wherein a composition that comprises IdeE2 comprises at least one further antigen. 
     
     
         3 . The antigenic composition of  claim 1  or  2 , wherein said at least one protein or polypeptide is selected from the group consisting of Eq5 and Eq8. 
     
     
         4 . The antigenic composition of  claim 1 , wherein said at least one protein or polypeptide is selected from the group consisting of EAG, Eq5 and Eq8 and which composition further comprises at least one antigen, which is selected from the group comprising a protein or a polypeptide designated CNE (or SEC), which has an amino acid sequence as shown in SEQ ID NO: 28, and a protein or a polypeptide designated ScIC, which has an amino acid sequence as shown in SEQ ID NO: 29. 
     
     
         5 . The antigenic composition of  claim 4 , wherein said at least one protein or polypeptide is selected from the group comprising IdeE and IdeE2. 
     
     
         6 . The antigenic composition of  claim 1 , which comprises the antigens EAG, ScIC, CNE (or SEC), Eq5, Eq8, IdeE and IdeE2, or which composition comprises the antigens EAG, ScIC, CNE (or SEC), Eq5, and Eq8. 
     
     
         7 . The antigenic composition of  claim 1 , wherein said at least one protein or polypeptide is selected from the group consisting of EAG, Eq8, and IdeE2 and which composition comprises at least one further antigen which is selected from the group comprising IdeE, Eq5, IdeZ2, Eqz5 and Eqz8. 
     
     
         8 . The antigenic composition of  claim 1 , wherein at least one antigen is recombinantly produced. 
     
     
         9 . The antigenic composition of  claim 1 , wherein at least one antigen is an isolated or purified antigen. 
     
     
         10 . The antigenic composition of  claim 1 , which comprises at least one recombinant vector and at least one polynucleotide inserted therein that encodes said at least one protein or polypeptide, and
 which vector is able to express said polypeptide in vivo in a non-human mammal susceptible to infection with  S. equi.      
     
     
         11 . The antigenic composition of  claim 10 , wherein the vector is an expression vector which is a plasmid or a viral vector and wherein said polynucleotide has a nucleotide sequence as shown in SEQ ID NOS: 12 and 14-21. 
     
     
         12 . The antigenic composition of  claim 1 , which is an immunogenic composition. 
     
     
         13 . A vaccine composition for protecting non-human mammals against infection of  Streptococcus equi , which comprises the antigenic composition of  claim 1  as immunizing component, and a pharmaceutically acceptable carrier. 
     
     
         14 . The vaccine composition of  claim 13 , which further comprises an adjuvant. 
     
     
         15 . The vaccine composition of  claim 13 , which is a vaccine that protects susceptible mammals, suitably horses, against strangles caused by  Streptococcus equi  subsp.  equi.    
     
     
         16 . The vaccine composition of  claim 13 , which is provided in a physiologically administrable form, and suitably is administrable by subcutaneous or intranasal inoculation. 
     
     
         17 . The vaccine composition of  claim 15 , which stimulates serum, mucosal and/or bronchial lavage antibody responses directed to  Streptococcus equi  antigens in mammals susceptible to  Streptococcus equi , suitably horses. 
     
     
         18 . A method for producing an antigen or an immunogen of an antigenic composition of  claim 1 , which method comprises
 (a) providing a DNA fragment encoding said antigen and introducing said fragment into an expression vector;   (b) introducing said vector, which contains said DNA fragment, into a compatible host cell;   (c) culturing said host cell provided in step (b) under conditions required for expression of the product encoded by said DNA fragment; and   (d) isolating the expressed product from the cultured host cell, and, optionally,   (e) purifying the isolated product from step (d) by affinity chromatography or other chromatographic methods known in the art.   
     
     
         19 . A method for preparation of a vaccine composition according to  claim 13 , which vaccine composition contains as immunizing component, said antigenic or immunogenic composition, said method comprising mixing said antigenic or immunogenic composition and a pharmaceutically acceptable carrier. 
     
     
         20 . Use of an antigenic or immunogenic composition of  claim 1  in the preparation of a vaccine protecting against  S. equi  infection inclusive of strangles caused by subsp.  equi  infection in horses. 
     
     
         21 . A method for the production of an antiserum, said method comprising administering an antigenic preparation of  claim 1  to an animal host to produce antibodies in said animal host and recovering antiserum containing said antibodies produced in said animal host. 
     
     
         22 . A method of prophylactic or therapeutic treatment of  S. equi  infection in non-human mammals, suitably horses, comprising administering to said mammal an immunologically effective amount of a vaccine composition of  claim 13  or an antiserum produced by administering an antigenic composition to an animal host to produce antibodies in said animal host and recovering antiserum containing said antibodies produced in said animal host,
 wherein said antigenic composition comprises at least one antigen, wherein said at least one antigen comprises at least part of a protein or polypeptide of  Streptococcus equi  subsp.  equi  or subsp.  zooepidemicus  and said at least part of said protein or polypeptide comprises at least one antigenic epitope or antigenic determinant of  Streptococcus equi , and wherein said protein or polypeptide is selected from the group comprising 
 a protein or polypeptide which is designated EAG and has an amino acid sequence as shown in SEQ ID NO: 13; 
 a protein or polypeptide which is designated IdeE and has an amino acid sequence as shown in SEQ ID NO: 10; 
 a protein or polypeptide which is designated IdeE2 and has an amino acid sequence as shown in SEQ ID NO: 1; 
 a protein or polypeptide which is designated Eq5 and has an amino acid sequence as shown in SEQ ID NO: 3; 
 a protein or polypeptide which is designated Eq8 and has an amino acid sequence as shown in SEQ ID NO: 5; 
 a protein or polypeptide which is designated IdeZ2 and has an amino acid sequence as shown in SEQ ID NO: 7; 
 a protein or polypeptide which is designated Eqz5 and has an amino acid sequence as shown in SEQ ID NO: 8; and 
 a protein or polypeptide which is designated Eqz8 and has an amino acid sequence as shown in SEQ ID NO: 9; 
 or an analog or fragment thereof, and wherein a composition which comprises EAG comprises at least one further antigen, which is a protein or polypeptide which is selected from the group comprising IdeE, IdeE2, Eq5, Eq8, IdeZ2, Eqz5 and Eqz8. 
 
     
     
         23 . A method for protecting horses against  Streptococcus equi  infection, which comprises inoculating a horse subcutaneously or intranasally with a vaccine composition of  claim 13  to induce an immune response against  Streptococcus equi  in said horse. 
     
     
         24 . The method of  claim 23 , wherein an immune response in the form of IgG and/or IgA and/or IgM antibodies in the nasopharyngeal mucus is induced in said horse. 
     
     
         25 . An antibody preparation comprising at least one, and suitably at least two, antibodies specific for a protein or polypeptide of the composition of  claim 1 , which antibody/antibodies is/are polyclonal or monoclonal; or which preparation comprises a fragment of said antibodies. 
     
     
         26 . The antibody preparation of  claim 25  which is used prophylactically or therapeutically against strangles and provides passive immunization when administered to a non-human mammal susceptible to infection by  Streptococcus equi  or infected by  Streptococcus equi.