Immunogenic compositions including rough phenotype Brucella host strains and complementation DNA fragments
AssigneeThe United States of America as represented by the Secretary of the Army
InventorsMikeljon Nikolich, David Hoover
Life of this patent
Estimating the term…
Abstract
Live attenuated vaccines against brucellosis and infection by other diseases are described. It has been discovered that trans complementation of the Brucella wboA gene can be used to maintain an expression vector in an attenuated Brucella host cell in a vaccinee. Further, heterologous antigens can be expressed using this Brucella platform, thus effecting a multivalent vaccine against Brucella and the disease corresponding to the heterologous antigen.
Claims32
An immunogenic composition comprising a live Brucella host cell having a rough phenotype, which host cell contains at least two mutations so as to effect sufficient attenuation such that upon exposure to a mammal the host cell will not exhibit full virulence of non-attenuated Brucella, wherein the host cell is transformed with a recombinant DNA construct replicable in Brucella, which DNA construct comprises:
- (i) a promoter recognizable by Brucella, and
- (ii) a complementation DNA fragment which encodes a peptide required for lipopolysaccharide O-sidechain synthesis so as to effect lipopolysaccharide O-sidechain synthesis in vivo and which is operably linked to the promoter and which complements a rough-conferring mutation in the host cell, thereby effecting a smooth phenotype in the host cell,
- wherein the association between the Brucella host cell and the DNA construct is such that following exposure to a mammal the DNA construct gradually separates from the Brucella host cell, whereupon the Brucella host cell reverts to a rough phenotype that is rapidly and safely cleared from the mammal.
An immunogenic composition comprising a live attenuated Brucella host cell having a rough phenotype, which host cell contains at least two mutations so as to effect sufficient attenuation such that upon exposure to a mammal the host cell will not exhibit full virulence of non-attenuated Brucella, wherein the host cell is transformed with a recombinant DNA construct replicable in Brucella, which DNA construct comprises:
- (i) a DNA fragment operably linked to a first promoter recognizable by Brucella, and encoding a heterologous antigen;
- and
- (ii) a complementation DNA fragment which encodes a peptide required for lipopolysaccharide O-sidechain synthesis so as to effect lipopolysaccharide O-sidechain synthesis in vivo and which is operably linked to a second promoter recognizable by Brucella, and which complements a rough-conferring mutation in the host cell, thereby effecting a smooth phenotype in the host cell cell,
- wherein the association between the Brucella host cell and the DNA construct is such that following exposure to a mammal the DNA construct gradually separates from the Brucella host cell, whereupon the Brucella host cell reverts to a rough phenotype that is rapidly and safely cleared from the mammal.
A vaccine against infection by brucellosis, comprising a live Brucella host cell having a rough phenotype, which host cell contains at least two mutations so as to effect sufficient attenuation such that upon exposure to a mammal the host cell will not exhibit full virulence of non-attenuated Brucella, wherein the host cell is transformed with a recombinant DNA construct replicable in Brucella, which DNA construct comprises:
- (i) a promoter recognizable by Brucella, and
- (ii) a complementation DNA fragment encodes a peptide required for lipopolysaccharide O-sidechain synthesis so as to effect lipopolysaccharide O-sidechain synthesis in vivo and which is operably linked to the promoter and which complements a rough-conferring mutation in the host cell, thereby effecting a smooth phenotype in the host cell,
- wherein the association between the Brucella host cell and the DNA construct is such that following exposure to a mammal the DNA construct gradually separates from the Brucella host cell, whereupon the Brucella host cell reverts to a rough phenotype that is rapidly and safely cleared from the mammal.
DNA construct pGSG5.
Dependencies are inferred from the claim text.