Selective humoral immune response of Balb/C mice to Brucella abortus proteins expressed by vaccinia virus recombinants.
Genes encoding Brucella abortus Cu/Zn superoxide dismutase (SOD) and a 54 kDa Escherichia coli HtrA homologue were cloned into shuttle plasmids pUV-1 and pSC11, and transfected into vaccinia virus to develop recombinants vUBSOD and vSB54. Control vaccinia virus recombinants vUV-1 and vSC11, carrying only the beta-gal reporter gene but no B. abortus DNA were also developed. Recombinants were analyzed in Western blotting using a polyclonal B. abortus immune serum. vUBSOD expressed a protein of apparent molecular weight of 28 kDa, composed of the 20 kDa B. abortus Cu/Zn-SOD and a protein approximately 8 kDa encoded by a portion of the vaccinia virus TK gene. vSB54 expressed a 54 kDa protein corresponding to the 54 kDa HtrA homologue. Recombinants vUSV-1 and vSC11 did not express B. abortus proteins. Groups of mice were inoculated intraperitoneally with 10(7) TCID50 of 1 of the 4 different recombinant vaccinia viruses and 5 weeks later their sera were analyzed for antibodies against vaccinia virus and B. abortus proteins. Each group of mice responded with antibodies to vaccinia virus. Sera of vSB54-inoculated mice recognized the 54 kDa HtrA homologue. vUBSOD did not induce a humoral immune response. These results represent the first report on the expression of B. abortus proteins by vaccinia virus recombinants and the first demonstrated immune response against a B. abortus protein expressed by such a recombinant.
Toth
T E
TE
Department of Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg 24061-0443, USA.
Cobb
J A
JA
Boyle
S M
SM
Roop
R M
RM
Schurig
G G
GG
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D000942:Antigens, Bacterial / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology*; D002003:Brucella abortus / Q000235:genetics / Q000276:immunology*; D003001:Cloning, Molecular; D015967:Gene Expression Regulation, Viral; D051379:Mice; D008807:Mice, Inbred BALB C; D010957:Plasmids; D011995:Recombination, Genetic; D014162:Transfection; D014616:Vaccinia virus / Q000235:genetics; D014765:Viral Vaccines / Q000008:administration & dosage*
D000914:Antibodies, Viral; D000942:Antigens, Bacterial; D014765:Viral Vaccines