Immunogenic composition
The disclosure provides synthetic (e.g. recombinant) pneumococcal saccharides comprising one or more repeat unit(s) →4)-β-D-Glcp-(1→4)-[Gro-(2→P→3)]-β-D-Galp-(1→4)-β-L-Rhap-(1→. Also provided are conjugates comprising a →4)-β-D-Glcp-(1→4)-[Gro-(2→P→3)]-β-D-Galp-(1→4)-β-L-Rhap-(1→, immunogenic compositions, vaccines and their use in preventing or treating infection by Streptococcus pneumoniae.
1. A synthetic pneumococcal saccharide comprising one or more repeat unit(s) →4)-β-D-Glcp-(1→4)-[Gro-(2→P→3)]-β-D-Galp-(1→4)-β-L-Rhap-(1→; wherein the pneumococcal saccharide is conjugated to a carrier protein; wherein the carrier protein is selected from a group consisting of CRM1 97, Diphtheria toxoid, tetanus toxoid, detoxified exotoxin A from P. aeruginosa , detoxified hemolysin A of S. aureus , clumping factor A, clumping factor B, E. coli FimH, E. coli FimHC, E. coli heat labile enterotoxin, detoxified variants of E. coli heat labile enterotoxin, Cholera toxin B subunit (CTB), cholera toxin, detoxified variants of cholera toxin, E. coli sat protein, the passenger domain of E. coli sat protein, C. jejuni AcrA, C. jejuni natural glycoproteins, S. pneumoniae pneumolysin, S. pneumoniae NOX, S. pneumoniae PspA, S. pneumoniae PcpA, S. pneumoniae PhtD, S. pneumoniae PhtE, S. pneumoniae ply, and S. pneumoniae LytB; wherein the pneumococcal saccharide is a hybrid oligosaccharide or polysaccharide having a structure: (B)n-A→ wherein A is an oligosaccharide containing at least 2, 3, 4, 5, 6, 7 or 8 monosaccharides, with a hexose monosaccharide derivative at the reducing end (indicated by the arrow in the diagram): wherein B is an oligosaccharide repeat unit →4)-β-D-Glcp-(1→4)-[Gro-(2→P→3)]-β-D-Galp-(1→4)-β-L-Rhap-(1→; and wherein n is at least 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or at least 20.
2. The pneumococcal saccharide according to claim 1 , comprising less than 500 repeat units.
3. The pneumococcal saccharide according to claim 2 , comprising 1 to 200 repeat units.
4. The pneumococcal saccharide according to claim 2 , comprising 2 to 50 repeat units.
5. The pneumococcal saccharide according to claim 2 , comprising 2 to 20 repeat units.
6. The pneumococcal saccharide according to claim 1 wherein A is an oligosaccharide identical to the repeat unit B with the exception that A comprises a hexose monosaccharide derivative at the reducing end of the oligosaccharide in place of the hexose monosaccharide at the reducing end of B.
7. The pneumococcal saccharide according to claim 6 , wherein A is →4)-β-D-GlcNAcp-(1→4)-[Gro-(2→P→3)]-β-D-Galp-(1→4)-β-L-Rhap-(1→).
8. A pneumococcal saccharide according to claim 1 , for use in the treatment or prevention of a disease caused by Streptococcus pneumoniae infection.
9. The pneumococcal saccharide according to claim 1 is a recombinant pneumococcal saccharide.
10. The pneumococcal saccharide according to claim 1 , wherein the hexose monosaccharide’ derivative is N-acetylglucosamine (GlcNAc), N-acetylgalactoseamine (GalNAc), 2,4-Diacetamido-2,4,6-trideoxyhexose (DATDH), N-acetylfucoseamine (FucNAc), or N-acetylquinovosamine (QuiNAc).
11. The pneumococcal saccharide according to claim 10 , wherein the monosaccharide derivative is N-acetylglucosamine.
12. An immunogenic composition comprising a pneumococcal saccharide comprising one or more repeat unit(s) →4)-β-D-Glcp-(1→4)-[Gro-(2→P→3)]-β-D-Galp-(1→4)-β-L-Rhap-(1→ conjugated to a carrier protein wherein the carrier protein is selected from a group comprising consisting of detoxified exotoxin A from P. aeruginosa (EPA), TT, DT, CRM197, PhtD, detoxified pneumolysin and protein D; wherein the pneumococcal saccharide is a hybrid oligosaccharide or polysaccharide having a structure: (B)n-A→ wherein A is an oligosaccharide containing at least 2, 3, 4, 5, 6, 7 or 8 monosaccharides, with a hexose monosaccharide derivative at the reducing end (indicated by the arrow in the diagram): wherein B is an oligosaccharide repeat unit →4)-β-D-Glcp-(1→4)-[Gro-(2→P→3)]-β-D-Galp-(1→4)-β-L-Rhap-(1→; and wherein n is at least 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or at least 20.
13. An immunogenic composition according to claim 12 , for use in the treatment or prevention of a disease caused by Streptococcus pneumoniae infection.
14. The immunogenic composition according to claim 12 , wherein the carrier protein is exotoxin A from P. aeruginosa (EPA).
15. The immunogenic composition according to claim 12 , further comprising an adjuvant.
16. A pneumococcal saccharide comprising one or more repeat unit(s) →4)-β-D-Glcp-(1→4)-[Gro-(2→P→3)]-β-D-Galp-(1→4)-β-L-Rhap-(1→ conjugated to a carrier protein, wherein the pneumococcal saccharide is a hybrid oligosaccharide or polysaccharide having a structure: (B)n-A→ wherein A is an oligosaccharide containing at least 2, 3, 4, 5, 6, 7 or 8 monosaccharides, with a hexose monosaccharide derivative at the reducing end (indicated by the arrow in the diagram): wherein B is an oligosaccharide repeat unit →4)-β-D-Glcp-(1→4)-[Gro-(2→P→3)]-β-D-Galp-(1→4)-β-L-Rhap-(1→; and wherein n is at least 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or at least 20, wherein the carrier protein is attached to a glucose or the hexose monosaccharide derivative of the pneumococcal saccharide.