Protection of BALB/c mice against homologous and heterologous species of Brucella by rough strain vaccines derived from Brucella melitensis and Brucella suis biovar 4.
OBJECTIVE
To evaluate stable rough mutants derived from Brucella melitensis 16M and B suis 2579 (biovar 4) as vaccines against homologous and heterologous Brucella spp in the BALB/c mouse model. DESIGN, ANIMALS, AND PROCEDURE: Rough mutants VTRM1 and VTRS1 were obtained from B melitensis 16M and B suis 2579, respectively, by allelic exchange of rfbU gene encoding mannosyltransferase with a Tn5-disrupted rfbU gene. Mice were vaccinated with VTRM1 or VTRS1 and challenge exposed 8 weeks later.


RESULTS
VTRM1 and VTRS1 replicated extensively in the spleen during the first 3 weeks of infection, then decreased rapidly. Antibodies specific for the O polysaccharide were not detected in sera of mice inoculated with either rough strain. Vaccination with VTRM1 or VTRS1 induced protection against virulent strains of B abortus (2308), B melitensis (16M), B suis biovar 1 (750), and B suis biovar 4 (2579). VTRM1 also protected against B ovis (PA) and against 4 field isolates of B abortus from bison or elk. VTRS1 conferred protection against 4 field isolates of B suis biovar 4 from reindeer. Vaccines prepared from live VTRM1 or VTRS1 provided significantly greater protection than that afforded by vaccines of killed cells in QS-21 adjuvant. Vaccination with VTRM1 containing VTRS1 gave minimal protection against the antigenically unrelated Listeria monocytogenes, thus demonstrating the immunologic specificity of protection against Brucella spp.


CONCLUSIONS
Results encourage evaluation, in primary host species, of VTRM1 and VTRS1, along with RB51, as alternative vaccines to strain 19, Rev 1, or other smooth phase vaccines.
Winter
A J
AJ
Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
Schurig
G G
GG
Boyle
S M
SM
Sriranganathan
N
N
Bevins
J S
JS
Enright
F M
FM
Elzer
P H
PH
Kopec
J D
JD
D000483:Alleles; D000818:Animals; D000914:Antibodies, Viral / Q000032:analysis / Q000276:immunology; D000956:Antigens, Viral / Q000032:analysis / Q000276:immunology; D016164:Bison; D015153:Blotting, Western / Q000662:veterinary; D002002:Brucella / Q000235:genetics / Q000276:immunology*; D002004:Brucella Vaccine / Q000276:immunology*; D017347:Brucella melitensis / Q000235:genetics / Q000276:immunology*; D002006:Brucellosis / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary*; D002417:Cattle; D003670:Deer; D005260:Female; D008089:Listeria monocytogenes / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C / Q000276:immunology*; D009154:Mutation; D012053:Reindeer; D012376:Rodent Diseases / Q000276:immunology / Q000517:prevention & control*; D013552:Swine; D014613:Vaccines, Attenuated / Q000494:pharmacology
D000914:Antibodies, Viral; D000956:Antigens, Viral; D002004:Brucella Vaccine; D014613:Vaccines, Attenuated