Molecular and immunological characterisation of recombinant Brucella abortus glyceraldehyde-3-phosphate-dehydrogenase, a T- and B-cell reactive protein that induces partial protection when co-administered with an interleukin-12-expressing plasmid in a DNA vaccine formulation.
To identify antigens of Brucella spp. that are potentially involved in stimulating a protective T-cell-mediated immune response, previous studies identified 10 clones from a Brucella abortus 2308 genomic library with primed lymphocytes as probes. One selected positive clone (182) contained an insert of 1.2 kb which was identified, sequenced and characterised. The deduced amino acid sequence of the open reading frame (ORF) revealed 82% and 81% identity to the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) enzymes from Agrobacterium tumefaciens and Xanthobacter flavus, respectively. Southern blot analysis demonstrated that the gap gene is present in only one copy in the Brucella genome. B. abortus GAPDH was then expressed in Escherichia coli as a fusion protein with the maltose-binding protein (MBP). To demonstrate the functional activity of Brucella GAPDH, E. coli gap mutants were transformed with a Brucella pMAL-gap construct. Genetic complementation was achieved and as a result E. coli mutants were able to grow on glucose or other carbon source medium. The humoral and cellular immune responses to the recombinant (r) GAPDH were characterised. In Western blots, sera from naturally infected cattle and sheep showed antibody reactivity against rGAPDH. In response to in-vitro stimulation by rGAPDH, splenocytes from mice vaccinated with rGAPDH or B. abortus S19 were able to produce gamma-interferon and tumour necrosis factor-a but not interleukin (IL)-4. Furthermore, gap associated with murine IL-12 gene in a DNA vaccine formulation partially protected mice against experimental infection.
Rosinha
Gracia M S
GMS
Myioshi
Anderson
A
Department of Biochemistry and Immunology and Institute for Investigation in Immunology - Millenium Institute, and *Department of General Biology, Federal University of Minas Gerais, Belo Horizonte, Brazil and †Department of Animal Health and Biomedical Sciences, University of Wisconsin, Madison, WI 53706, USA.
Azevedo
Vasco
V
Department of Biochemistry and Immunology and Institute for Investigation in Immunology - Millenium Institute, and *Department of General Biology, Federal University of Minas Gerais, Belo Horizonte, Brazil and †Department of Animal Health and Biomedical Sciences, University of Wisconsin, Madison, WI 53706, USA.
Splitter
Gary A
GA
Department of Biochemistry and Immunology and Institute for Investigation in Immunology - Millenium Institute, and *Department of General Biology, Federal University of Minas Gerais, Belo Horizonte, Brazil and †Department of Animal Health and Biomedical Sciences, University of Wisconsin, Madison, WI 53706, USA.
Oliveira
Sergio C
SC
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002004:Brucella Vaccine / Q000276:immunology*; D002003:Brucella abortus / Q000201:enzymology* / Q000235:genetics / Q000276:immunology; D002007:Brucellosis, Bovine / Q000276:immunology* / Q000382:microbiology / Q000517:prevention & control; D002417:Cattle; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D005816:Genetic Complementation Test; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000235:genetics / Q000276:immunology*; D018664:Interleukin-12 / Q000235:genetics / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010957:Plasmids / Q000235:genetics; D016133:Polymerase Chain Reaction; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D017386:Sequence Homology, Amino Acid; D018417:Th1 Cells / Q000276:immunology*; D019444:Vaccines, DNA / Q000276:immunology
D002004:Brucella Vaccine; D004269:DNA, Bacterial; D011994:Recombinant Proteins; D019444:Vaccines, DNA; D018664:Interleukin-12; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases