Comparison of the efficacies of Rhodococcus equi recombinant vaccine in mice.
Abstract: is an important bacterial pathogen and causes severe chronic granulomatous pneumonia in foals below 6 months of age. It has also become an opportunistic and emerging pathogen in immunocompromised humans. Vaccination is the most cost-effective strategy for controlling and preventing this infection. Although several potential virulence genes and candidate immunogens have been identified over the years, no effective vaccine is currently available to prevent disease in horses. Recently, bacterial vector vaccines have been shown to be promising for In this study, the gene of was cloned into Protein Expression System small ubiquitin-related modifier (pET-SUMO) expression vectors and transferred into BL21 (DE3). Also, adjuvant significantly affects the efficacy of recombinant vaccines. Therefore, native VapA and recombinant VapA were formulated with Immunostimuling Microparticle System (IMS 3012) or PetGel A (recommended for horses) and subcutaneously administered to mice. The immunization effect of four different vaccines was determined by assaying antibody titers and survival rates. The antibody response was slightly higher in the PetGel A formulations than IMS 3012. Survival rates were lower in the PetGel A formulations than IMS 3012. Given these results, recombinant VapA adjuvanted with PetGel A represents a promising formulation for developing new-generation vaccines.
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Publication Date: 2025-05-15 PubMed ID: 40693028PubMed Central: PMC12276374DOI: 10.30466/vrf.2024.2028438.4266Google Scholar: Lookup
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Summary
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The research article explores the effectiveness of different forms of a Rhodococcus equi recombinant vaccine on mice, with one formulation proving to be more promising for the development of new-generation vaccines.
Overview of Research
In order to understand this research article, it is essential to comprehend that Rhodococcus equi is a dangerous bacterial pathogen primarily affecting young foals, and has evolved to pose risk to immunocompromised human beings as well. Although numerous potential virulence genes and candidate immunogens have been discovered over time, there has been no significant breakthrough in devising an effective vaccine against Rhodococcus equi.
- In the quest to find an effective Rhodococcus equi vaccine, the authors experimented with bacterial vector vaccines, which have shown promise in handling Rhodococcus equi.
- The researchers cloned a particular Rhodococcus equi gene into Protein Expression System small ubiquitin-related modifier (pET-SUMO) expression vectors and transferred them into Escherichia coli BL21 (DE3), a type of bacteria.
- The study also considered that the effectiveness of recombinant vaccines can significantly be influenced by the adjuvant, a substance which enhances the body’s immune response to an antigen.
Methodology
- VapA protein (significant to Rhodococcus equi) and its recombinant form were crafted with two types of adjuvants, Immunostimulating Microparticle System (IMS 3012) and PetGel A (recommended for horses).
- The modified vaccines were then administered to mice through a process known as subcutaneous administration, where the vaccine is injected under the skin.
Results
- After administering the vaccines, the researchers evaluated their effects by measuring antibody titers (concentration of antibodies in the blood, indicating the strength of the immune response) and survival rates of the mice.
- While both types of formulations stimulated an immune response, the vaccines combined with PetGel A led to a slightly higher antibody response compared to those formulated with IMS 3012.
- On the other hand, survival rates were higher with the IMS 3012 based vaccines compared to those with PetGel A.
Conclusion
- Despite its lower survival rates, the recombinant VapA vaccine formulated with PetGel A is considered promising for the development of new Rhodococcus equi vaccines, probably due to its higher immune response initiation.
Cite This Article
APA
Golen GS, Erganiş O, Balevi A.
(2025).
Comparison of the efficacies of Rhodococcus equi recombinant vaccine in mice.
Vet Res Forum, 16(5), 253-259.
https://doi.org/10.30466/vrf.2024.2028438.4266 Publication
Researcher Affiliations
- Department of Microbiology, Faculty of Veterinary Medicine, Aksaray University, Aksaray, Türkiye.
- Department of Microbiology, Faculty of Veterinary Medicine, Selçuk University, Konya, Türkiye.
- Department of Microbiology, Faculty of Veterinary Medicine, Selçuk University, Konya, Türkiye.
Conflict of Interest Statement
The authors declare no conflict of interest.
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