Group B Streptococcus vaccine

Abstract

The invention concerns a vaccine capable of protecting a recipient from infection caused group B Streptococcus. The vaccine comprises polysaccharide-protein moieties or protein moieties without a polysaccharide. The vaccine can contain, inter alia, (a) a group B Streptoccus polysaccharide conjugated to (b) either the N-terminal region of the epsilon antigen, a fragment thereof or their functional derivatives such that the vaccine retains the ability to elicit protective antibodies against group B Streptoccus. The vaccine may contain only one type of such polysaccharide-protein unit or may contain a mixture of more than one type of unit. Alternatively, the vaccine may contain antigens from different species of Group B Streptococcus. Additionally, the invention concerns a passive vaccine obtained following immunization with either the capsular polysaccharide-protein conjugate or the non-conjugated protein.

What is claimed is:  
     
         1 . A conjugate vaccine capable of conferring host immunity to an infection by group B Streptococcus, said vaccine comprising (a) a group B Streptococcus capsular polysaccharide conjugated to (b) the N-terminal region of the epsilon antigen or a fragment thereof, wherein said N-terminal region or fragment thereof is capable of eliciting protective antibodies against said group B Streptococcus, and wherein said conjugate vaccine is substantially free of streptococcal proteins other than said C protein epsilon antigen, and both said capsular polysaccharide and said C protein contribute to the development of said protective host immunity.  
     
     
         2 . A conjugate vaccine capable of conferring host immunity to an infection by group B Streptococcus, said vaccine comprising (a) a group B Streptococcus capsular polysaccharide that elicits antibodies to group B Streptococcus; conjugated to (b) the N-terminal region of the epsilon antigen or fragment thereof, and further comprising said capsular polysaccharide conjugated to a C-protein selected from the group B Streptococcus C proteins consisting of at least one of an alpha antigen, a beta antigen, fragments of said alpha antigen and fragments of said beta antigen, wherein said N-terminal region or fragment thereof is capable of eliciting protective antibodies against said group B Streptococcus and both said capsular polysaccharide and said C proteins contribute to the development of said protective host immunity.  
     
     
         3 . A passive vaccine that confers passive host immunity against an infection by a C protein epsilon antigen positive group B Streptococcus wherein said passive vaccine comprises a composition containing a therapeutically effective amount of antibodies raised against a conjugate vaccine, said conjugate vaccine comprising (a) a capsular polysaccharide that elicits antibodies to group B Streptococcus; conjugated to (b) the N-terminal region of the epsilon antigen or fragment thereof, and wherein said N-terminal region or fragment thereof is capable of eliciting protective antibodies against said group B Streptococcus, and wherein said conjugate vaccine is substantially free of streptococcal proteins other than said C protein epsilon antigen, and both said capsular polysaccharide and said C protein contributes to the development of said protective host immunity.  
     
     
         4 . A passive vaccine that confers passive host immunity to an infection by group B Streptococcus wherein said passive vaccine comprises a composition containing a therapeutically effective amount of antibodies raised against a conjugate vaccine, said conjugate vaccine comprising: (a) a group B Streptococcus capsular polysaccharide that elicits antibodies to Group B Streptococcus: conjugated to (b) the N-terminal region of the epsilon antigen or fragment thereof, and further comprising said capsular polysaccharide conjugated to a C-protein selected from the group B Streptococcus C proteins selected from the group consisting of at least one of an alpha antigen, a beta antigen, fragments of said alpha antigen and fragments of said beta antigen, wherein said N-terminal region or fragment thereof is capable of eliciting protective antibodies against said group B Streptococcus and both said capsular polysaccharide and C proteins contribute to the development of said protective host immunity.  
     
     
         5 . A method for preventing or attenuating an infection caused by a group B Streptococcus comprising administering to an individual, an effective amount of the conjugate vaccine of any one of claims  1  or  2 .  
     
     
         6 . A method for preventing or attenuating an infection caused by a group B Streptococcus comprising administering to a female an effective amount of the conjugate vaccine of any one of claims  1  or  2 , said vaccine capable of conferring immunity to said infection to an unborn offspring of said female.  
     
     
         7 . A method for preventing or attenuating an infection caused by a group B Streptococcus comprising administering to an individual an effective amount of an antisera elicited from the exposure of a second individual to the conjugate vaccine of any one of claims  1  or  2 .  
     
     
         8 . The conjugate vaccine of any one of claims  1 - 4  wherein said capsular polysaccharide is type-specific.  
     
     
         9 . The conjugate vaccine of any one of claims  1 - 4  wherein said capsular polysaccharide is group-specific.  
     
     
         10 . The vaccine of any one of claims  1 - 4  wherein a functional equivalent or a derivative of the N-terminal region of the epsilon antigen is used in the conjugate vaccine.  
     
     
         11 . The vaccine of any one of claims  1 - 4  or  12 - 15 , further comprising a pharmacologically acceptable solution.  
     
     
         12 . The conjugate vaccine of any one of claims  1 - 4  or  12 - 15 , wherein said epsilon antigen from more than one strain of Group B Streptococcus is used in said vaccine.  
     
     
         13 . A vaccine capable of conferring host immunity to an infection by group B Streptococcus, said vaccine comprising the N-terminal region of the epsilon antigen or a fragment thereof, wherein said N-terminal region or fragment thereof is capable of eliciting protective antibodies against said group B Streptococcus.  
     
     
         14 . A vaccine capable of conferring host immunity to an infection by group B Streptococcus, said vaccine comprising the N-terminal region of the epsilon antigen or fragment thereof, and further comprising a C-protein selected from the group B Streptococcus C proteins consisting of at least one of an alpha antigen, a beta antigen, fragments of said alpha antigen and fragments of said beta antigen, wherein said N-terminal region or fragment thereof is capable of eliciting protective antibodies against said group B Streptococcus.  
     
     
         15 . A passive vaccine that confers passive host immunity against an infection by a C protein epsilon antigen positive group B Streptococcus wherein said passive vaccine comprises a composition containing a therapeutically effective amount of antibodies raised against a first vaccine comprising the N-terminal region of the epsilon antigen or fragment thereof, and wherein said N-terminal region or fragment thereof is capable of eliciting protective antibodies against said group B Streptococcus and said first vaccine is substantially free of streptococcal proteins other than said C protein epsilon antigen.  
     
     
         16 . A passive vaccine that confers passive host immunity to an infection by group B Streptococcus wherein said passive vaccine comprises a composition containing a therapeutically effective amount of antibodies raised against a first vaccine, said first vaccine comprising the N-terminal region of the epsilon antigen or fragment thereof, and further comprising group B Streptococcus C protein selected from the group consisting of at least one of an alpha antigen, a beta antigen, or fragments of said alpha antigen and fragments of said beta antigen, wherein said N-terminal region or fragment thereof is capable of eliciting protective antibodies.  
     
     
         17 . The plasmid pJMS36 comprising the DNA of FIG. 6A encoding the N-terminal region of the epsilon antigen.