Abstract
Anthrax is primarily recognized as an affliction of herbivores with incubation period ranging from three to five days post-infection. Currently, the Sterne live-spore vaccine is the only vaccine approved for control of the disease in susceptible animals. While largely effective, the Sterne vaccine has several problems including adverse reactions in sensitive species, ineffectiveness in active outbreaks and incompatibility with antibiotics. These can be surmounted with the advent of recombinant peptides (non-living) next generation vaccines. The candidate vaccine antigens comprised of recombinant protective antigen (PA), spore-specific antigen (bacillus collagen-like protein of anthracis, BclA) and formaldehyde inactivated spores (FIS). Presently, little information exists on the protectivity of these novel vaccine candidates in susceptible ruminants. Thus, this study sought to assess the immunogenicity of these vaccine candidates in goats and evaluate their protectivity using an in vivo mouse model. Goats receiving a combination of PA, BclA and FIS yielded the highest antibody and toxin neutralizing titres compared to recombinant peptides alone. This was also reflected in the passive immunization experiment whereby mice receiving immune sera from goats vaccinated with the antigen combination had higher survival post-challenge. In conclusion, the current data indicate promising potential for further development of non-living anthrax vaccines in ruminants.
Highlights
Anthrax, a disease widely recognized as a primary disease of ruminants[1], is caused by the Gram-positive, aerobic, spore-forming bacterium Bacillus anthracis
We have previously shown that 70% of NMRI mice vaccinated with a combination of protective antigen (PA), BclA and lipopeptide adjuvant were protected against virulent challenge with B. anthracis Ames strain spores[37]
Significant changes in levels of anti-PA IgG were observed after the second vaccination with recombinant PA (rPA) + rBclA+ lipopeptide adjuvant
Summary
A disease widely recognized as a primary disease of ruminants[1], is caused by the Gram-positive, aerobic, spore-forming bacterium Bacillus anthracis. The Sterne live spore vaccine is currently the only vaccine of choice for the control of anthrax in domestic animals It is an attenuated pXO1+, pXO2− strain (34F2)[16] known to induce good levels of immunity without clinical signs of the disease. An acellular vaccine formulation comprising of recombinant PA (rPA) and two other antigens; Bacillus collagen-like protein of anthracis (rBclA) and formaldehyde inactivated spores (FIS) were administered in a goat model and the resulting immune response and protection evaluated. We have previously shown that 70% of NMRI mice vaccinated with a combination of PA, BclA and lipopeptide adjuvant were protected against virulent challenge with B. anthracis Ames strain spores[37]. The adjuvant is well-defined, superior to conventional preparations and shows no untoward effects in animals[38]
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.