Immunological responses to recombinant cysteine synthase A of Brucella abortus in BALB/c mice

World J Microbiol Biotechnol. 2013 May;29(5):907-13. doi: 10.1007/s11274-012-1247-3. Epub 2012 Dec 27.

Abstract

Brucellosis is a worldwide zoonotic disease. No Brucella vaccine is available for use in humans, and existing animal vaccines have limitations. There is a need to develop a safe and effective vaccine against human and animal brucellosis. In the present study, we generated recombinant cysteine synthase A (rCysK) of Brucella abortus in Escherichia coli and purified it up to homogeneity by metal affinity chromatography. The immunogenicity and protective efficacy of purified rCysK were evaluated in BALB/c mice with Freund's adjuvant, aluminium hydroxide gel or without any adjuvant. High titres of anti-rCysK IgG antibody predominated by IgG1 were observed in all immunized mice. After stimulation with rCysK, the spleen lymphocytes of mice immunized with CysK formulated with aluminium hydroxide gel produced significant levels of IFN-γ. Protection against challenge with virulent B. abortus strain 544 was determined in BALB/c mice, and significant protection was observed in all CysK immunized groups when compared with PBS control. Among all the CysK vaccine groups, comparatively better protection was observed in mice immunized with aluminium hydroxide gel (1.064 units of protection). Overall, the results of the study suggest that rCysK induces primarily Th2 type of immune response and provides partial protection against B. abortus challenge.

MeSH terms

  • Animals
  • Antibodies, Bacterial / immunology
  • Bacterial Proteins / genetics
  • Bacterial Proteins / immunology*
  • Brucella abortus / enzymology*
  • Brucella abortus / genetics
  • Brucella abortus / immunology
  • Brucellosis / immunology*
  • Brucellosis / microbiology
  • Cysteine Synthase / genetics
  • Cysteine Synthase / immunology*
  • Female
  • Humans
  • Immunization
  • Mice
  • Mice, Inbred BALB C
  • Th1 Cells / immunology

Substances

  • Antibodies, Bacterial
  • Bacterial Proteins
  • Cysteine Synthase