title: Novel use of anaerobically induced promoter, dmsA, for controlled expression of fragment C of tetanus toxin in live attenuated Salmonella enterica serovar Typhi strain CVD 908-htrA.
abstract: The anaerobically induced promoter dmsA (PdmsA) was adapted to optimize in vivo expression of foreign antigens in attenuated Salmonella enterica serovar Typhi live vector vaccines CVD 908-htrA. PdmsA from Escherichia coli and two derivatives, PdmsA2 and PdmsA3 were cloned into a plasmid driving the expression of a gene encoding tetanus toxin fragment C. Expression of fragment C varied from a low level induced by pTETdmsA, to moderate and high levels induced, respectively, by pTETdmsA2 and pTETdmsA3. Mice were immunized intranasally with CVD 908-htrA harboring pTETdmsA2 or pTETdmsA3, and the serum antitoxin response was compared to that elicited by CVD 908-htrA(pTETnir15) (Pnir15 is a benchmark anaerobically activated promoter). S. Typhi carrying pTETdmsA2 elicited modest tetanus antitoxin titers while S. Typhi harboring pTETdmsA3 generated elevated titers (GMT=55384) that were higher than elicited by pTETnir15 (GMT=4354) (P=0.007). Mice immunized with CVD 908-htrA carrying pTETdmsA3 and pTETnir15 survived tetanus toxin challenge. P(dmsA) derivatives are attractive promoters for in vivo expression of foreign genes in attenuated live vector vaccines.
authors.affiliation: Department of Pediatrics, University of Maryland School of Medicine, Center for Vaccine Development, 685 West Baltimore Street, Baltimore, MD 21201, USA. naorr@actcom.co.il
authors.forename: N
authors.initials: N
authors.lastname: Orr
authors.forename: J E
authors.initials: JE
authors.lastname: Galen
authors.forename: M M
authors.initials: MM
authors.lastname: Levine
mesh_terms: D000693:Anaerobiosis; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood / Q000276:immunology; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology / Q000633:toxicity; D001483:Base Sequence; D015153:Blotting, Western; D003001:Cloning, Molecular; D016384:Consensus Sequence / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D005798:Genes, Bacterial / Q000235:genetics*; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D009566:Nitrates / Q000494:pharmacology; D010446:Peptide Fragments / Q000096:biosynthesis / Q000235:genetics* / Q000276:immunology* / Q000633:toxicity; D011401:Promoter Regions, Genetic / Q000235:genetics*; D022562:Salmonella Vaccines / Q000235:genetics* / Q000276:immunology; D012485:Salmonella typhi / Q000235:genetics / Q000276:immunology; D015996:Survival Rate; D013744:Tetanus Toxin / Q000096:biosynthesis / Q000235:genetics* / Q000276:immunology* / Q000633:toxicity; D014613:Vaccines, Attenuated / Q000235:genetics* / Q000276:immunology; D014614:Vaccines, Synthetic / Q000235:genetics* / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D007074:Immunoglobulin G; D009566:Nitrates; D010446:Peptide Fragments; D022562:Salmonella Vaccines; D013744:Tetanus Toxin; D014613:Vaccines, Attenuated; D014614:Vaccines, Synthetic; C040635:tetanus toxin fragment C