Plant-Based Antigen Production: A Promising Direction in Vaccine Development for the Livestock Industry
Infectious bronchitis, caused by the IBV virus, causes significant economic losses to the poultry industry. The disease spreads rapidly, directly affecting growth rate, productivity, and egg quality. Economic losses are estimated to reach up to 15–25% of total production value. Based on these practical demands, Dr. Hoang Thi Thu Hang and the research team of the Institute of Biology – Vietnam Academy of Science and Technology carried out the project: “Research and evaluation of the biological characteristics of the recombinant plant-derived Spike protein of the virus causing infectious bronchitis in chickens (Avian Infectious Bronchitis Virus – IBV)”, code VAST02.03/21-22. The research focused on expressing the recombinant Spike protein of the IBV virus in a plant system and evaluating its ability to stimulate immunity in laboratory animals. This is an important step toward mastering the technology and improving the effectiveness of disease prevention in the poultry industry in Vietnam.
Diagram of the research design, expression, and activity evaluation of the recombinant S1e-COBRA protein
The research team used the tobacco plant Nicotiana benthamiana to produce the Spike protein of the virus with the desired structure and activity in a short time. Specifically, based on IBV sequences in the gene bank and bioinformatics tools, the team designed an artificial gene segment, S1e-COBRA, encoding a broad-spectrum antigen of multiple IBV strains circulating in Vietnam, China, and Thailand (during 2014–2021). This gene segment was introduced into tobacco leaves through an expression vector system and intermediary bacteria to “produce” a protein homologous to the protein of the virus in nature. The recombinant protein was then extracted, purified, and tested in an animal model to evaluate its ability to stimulate the immune system, laying the groundwork for the development of vaccine candidates in the next phase.
A. Analysis of the presence of the S1e-COBRA protein produced in the tobacco plant
B. Specific antibody titers in chickens after injection with the S1e-COBRA protein (Source: Hang Thi Thu Hoang, Tra Thi Nguyen et al. (2025) Vet. Res. Commun. 49:196)
With the cooperation of the Department of Immunochemistry (Institute of Biology), the research achieved promising results: chicks injected with the recombinant protein were able to produce specific IgY antibodies at a high level. In particular, when challenged with a highly virulent IBV strain, the group of chickens injected with S1e-COBRA showed only mild symptoms and recovered quickly. Notably, this antigen design method is highly flexible, responding to many different virus variants, suitable for the rapidly mutating nature of the IBV virus.
The results of the project have laid the foundation for continuing to refine the technological process, advancing toward the development of IBV vaccine candidates capable of practical application in production in Vietnam.
Translated by Quoc Khanh
Link to Vietnamese version
