Selection of Vaccine Candidates Against Pseudomonas koreensis Using Reverse Vaccinology and a Preliminary Efficacy Trial in Tor tambroides (Empurau)

CINDY JIA YUNG, KHO (2024) Selection of Vaccine Candidates Against Pseudomonas koreensis Using Reverse Vaccinology and a Preliminary Efficacy Trial in Tor tambroides (Empurau). Masters thesis, UNIMAS.

	PDF (Please get the password by email to repository@unimas.my , or call ext: 3942 / 3973 / 3933) Thesis Master_Cindy Kho Jia Yung.ftext.pdf Restricted to Registered users only Download (2MB) | Request a copy
	PDF Thesis Master_Cindy Kho Jia Yung -24 pages.pdf Download (314kB)
	PDF DSVA _Cindy Kho Jia.pdf Restricted to Repository staff only Download (124kB) | Request a copy

Abstract

The unregulated and/or incorrect use of antimicrobial agents against diseases of farmed aquatic species poses a considerable threat to the development and growth of a sustainable aquaculture industry. Hence, vaccination has emerged as a pivotal strategy to mitigate this threat. This study marks the first utilization of reverse vaccinology to develop subunit vaccines against Pseudomonas koreensis infection in Empurau (Tor tambroides). WGS analysis revealed that the genomic size of P. koreensis CM-01 is 6,171,880 bp and has a G+C content of 60.5%. The proteome (5,538 proteins) was screened against various filters to prioritize proteins based on features that are associated with virulence, subcellular localization, transmembrane helical structure, antigenicity, essentiality, non-homology with the host proteome, molecular weight, and stability, which led to the identification of eight potential vaccine candidates. These potential vaccine candidates were cloned and expressed, with six achieving successful expression and purification. The antigens were formulated into two distinct vaccine mixtures, Vac A and Vac B, and their protective efficacy was assessed through in vivo challenge experiments. Vac A and Vac B demonstrated high protective efficacies of 100% and 81.2%, respectively. Histological analyses revealed reduced tissue damage in vaccinated fish after experimental infection, with Vac A showing no adverse effects, whereas Vac B exhibited mild degenerative changes. Quantitative real-time PCR results showed a significant upregulation of TNF-α and downregulation of IL-1β in the kidneys, spleen, gills, and intestine in both Vac A- and Vac B immunized fish after challenged with P. koreensis. Additionally, IL-8 exhibits tissue-specific differential expression, with significant upregulation in the kidney, gills, and intestine, and downregulation in the spleen, particularly notable in Vac A immunized fish. The research underscores the effectiveness of the reverse vaccinology approach in fish and demonstrates the promising potential of Vac A and Vac B as recombinant subunit vaccines.

Actions (For repository members only: login required)

View Item