Immunogenic compositions

Abstract

The present invention is directed towards conjugates comprising fragments of the capsular polysaccharide of Type III Group B Streptococcus (GBS). Suitable fragments may be produced synthetically or by depolymerisation of native polysaccharide.

1 - 8 . (canceled) 
     
     
         9 . A conjugate having the following structure: 
       
         
           
           
               
               
           
         
         wherein P is a carrier protein, wherein X is either: 
       
       
         
           
           
               
               
           
         
         n′ is an integer from 1 to 10, n″ is an integer from 2 to 9 and wherein n′″ is 1. 
       
     
     
         10 . The conjugate of  claim 9 , wherein the carrier protein is selected from the group consisting of diphtheria toxoid, CRM197, and tetanus toxoid. 
     
     
         11 . The conjugate of  claim 10 , wherein the oligosaccharide is a synthetic oligosaccharide. 
     
     
         12 . The conjugate of  claim 10 , wherein the oligosaccharide is prepared by depolymerisation of GBS serotype III CPS. 
     
     
         13 . A composition comprising the conjugate of  claim 9  and a pharmaceutically acceptable excipient. 
     
     
         14 . The composition of  claim 13 , further comprising an adjuvant. 
     
     
         15 . A method of raising an immune response in a mammal, comprising administering the composition of  claim 13  to the mammal.