Carrier molecule for antigens
The invention provides a conjugate comprising an antigen and a carrier molecule, wherein the carrier molecule comprises a BP-2a antigen and a spb1 antigen. BP-2a and spb1 are Streptococcus agalactiae antigens. The conjugate may be used in a method for raising an immune response in a mammal, the method comprising administering the conjugate to the mammal. Also provided are pharmaceutical compositions, particularly vaccines, comprising the conjugate.
1. A conjugate comprising an antigen and a carrier molecule, wherein the carrier molecule comprises BP-2a polypeptides derived from different Streptococcus agalactiae strains and a Streptococcus agalactiae spb1 polypeptide as a single polypeptide chain, said polypeptide chain having an amino acid sequence at least 70% identity to SEQ ID NO:276.
2. The conjugate according to claim 1 , wherein the spb1 polypeptide comprises a sequence selected from the group consisting of:
(a) the amino acid sequence of SEQ ID NO:206; and
(b) a fragment of SEQ ID NO:206 comprising amino acids 185 to 468.
3. The conjugate according to claim 1 , wherein the carrier molecule comprises a BP-2a polypeptide having an amino acid sequence selected from the group consisting of
SEQ ID NO:36, SEQ ID NO:38, SEQ ID NO:40, SEQ ID NO:42, SEQ ID NO:44, and SEQ ID NO:46.
4. The conjugate according to claim 1 , wherein said BP-2a polypeptides are separated by a linker amino acid sequence.
5. The conjugate according to claim 1 , wherein the antigen is a saccharide.
6. The conjugate according to claim 5 , wherein the saccharide is a capsular saccharide from Streptococcus agalactiae.
7. The conjugate according to claim 6 , wherein the saccharide is a capsular saccharide from Streptococcus agalactiae serotype II or V.
8. A pharmaceutical composition comprising a conjugate according to claim 1 in combination with a pharmaceutically acceptable carrier.
9. The pharmaceutical composition according to claim 8 , comprising a mixture of conjugates comprising saccharides from at least two of Streptococcus agalactiae serotypes selected from the group consisting of types Ia, Ib, II, III and V.
10. A method for raising an immune response in a mammal, comprising administering an immunologically effective amount of a conjugate according to claim 1 to the mammal.
11. A conjugate comprising an antigen and a carrier molecule, wherein the carrier molecule comprises an amino acid sequence having SEQ ID NO:276.
12. A method for raising an immune response in a mammal, comprising administering an immunologically effective amount of a pharmaceutical composition according to claim 8 to the mammal.
13. The conjugate according to claim 11 , wherein the antigen is a saccharide.
14. The conjugate according to claim 13 , wherein the saccharide is a capsular saccharide from Streptococcus agalactiae.
15. The conjugate according to claim 14 , wherein the saccharide is a capsular saccharide from Streptococcus agalactiae serotype II or V.
16. A pharmaceutical composition comprising a conjugate according to claim 11 in combination with a pharmaceutically acceptable carrier.
17. The pharmaceutical composition according to claim 16 , comprising a mixture of conjugates comprising saccharides from at least two of Streptococcus agalactiae serotypes selected from the group consisting of types Ia, Ib, II, III and V.
18. A method for raising an immune response in a mammal, comprising administering an immunologically effective amount of a conjugate according to claim 11 to the mammal.