Brucellosis 2003 proceedings - PHIDIAS

Poster Session
indicated that HS encapsulated conserved its antigenicity. Therefore, a study of
protection against an experimental challenge with B. melitensis (Bm) H 38 in BALB/c
mice was performed. The animals were vaccinated subcuteanously with both free
and encapsulated HS. Immunized and control mice were challenged 8 weeks later
with Bm (ip). HS-MP conferred significant protection in comparison with free HS
immunized mice or non-immunized control group. Moreover, this protection was
similar to that conferred by the Rev 1 reference vaccine.
95- THE CONSTRUCTION AND in vitro EVALUATION OF DNA VACCINES AND
CANDIDATE ANTIGENS FOR PROTECTION AGAINST BRUCELLOSIS.
Nicky Commander, Sonia Miguel Salvador, Alison Vickers, Rachel Ives. Veterinary Laboratories
Agency, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, UK.
Five novel candidate antigens were selected for development into DNA
vaccines. Specific primers were designed for each of the candidates to include kozac
sequences and unique restriction sites to facilitate cloning. Commercially available
eukaryotic expression constructs were used as the backbone for the DNA vaccine.
Prokaryotic expression constructs designed to generate specific recombinant fusion
proteins were also produced. All plasmid identities were verified by sequencing.
Expression from prokaryotic constructs was determined through SDS PAGE and
western blotting studies. Specific proteins were purified through various affinity
chromatography techniques. Expression from DNA vaccines was verified through
transient transfection of Cos7 cells, and detection of specific gene transcription
through RT-PCR or detection of expressed protein through indirect
immunofluoresence assay. This poster describes the generation and quality control
aspects of DNA vaccine production that are essential to the success of the study.
96- THE DEVELOPMENT AND ASSESSMENT OF 5 NOVEL DNA BASED
VACCINES FOR PROTECTION AGAINST Brucella spp.
Nicky Commander, Rachel Ives, Sonia Miguel Salvador, Pauline Groussaud. Veterinary Laboratories
Agency, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, UK.
Brucellosis is a zoonotic disease of considerable socio-economic importance.
Vaccination is considered to be an important component of control and eradication
strategies. Currently available vaccines for animal brucellosis are based upon live
attenuated strains of the organism. Although effective, these vaccines are impractical
due to their persistence in the host and associated residual virulence, pathogenicity
to humans, and induction of an immune response that cannot be distinguished from a
natural infection. Effective defined non-living or sub-unit vaccines have the potential
to overcome these problems. Here we describe the rational selection, construction
and evaluation of 5 novel DNA based vaccines. Candidate antigens were selected
from genome data and post genomic analysis. DNA vaccines based upon omp25,
acvB, FrpB, invasion protein B, and FliC have been assessed for immunogenicity
and protective efficacy in the Balb/c mouse model. Each vaccine was capable of
generating a Brucella specific Th1 biased immune response, as determined by
serology and antigen specific cytokine responses. Two of the vaccine candidates,
omp25 and invasion protein B, were able to provide a significant level of protection to
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Brucellosis 2003 International Research Conference