Development of a Novel Multi-Epitope Vaccine Candidate against Streptococcus Iniae Infection in Fish: An...

Area of Science:

• Aquatic Animal Health
• Vaccinology
• Bioinformatics

Background:

• Streptococcus Iniae infection causes significant economic losses in aquaculture globally.
• Current vaccines and control strategies for Streptococcus Iniae are limited.
• Multi-epitope vaccines offer a promising approach for enhanced disease prevention.

Purpose of the Study:

• To design and evaluate a novel multi-epitope vaccine against Streptococcus Iniae infection in fish.
• To identify and utilize key immunogenic proteins and epitopes from Streptococcus Iniae.
• To computationally assess the vaccine's physicochemical properties, structure, and receptor interactions.

Main Methods:

• Bioinformatic analysis and epitope prediction of six Streptococcus Iniae immunogenic proteins (FBA, ENO, Sip11, GAPDH, MtsB, SCPI).
• Construction of a multi-epitope vaccine incorporating B cell, T cell, and IFNγ epitopes, and an interleukin-8 domain.
• In silico evaluation of vaccine physicochemical features, antigenicity, secondary/tertiary structure, and molecular docking with its receptor.
• Adaptation of the vaccine's nucleotide sequence for expression in Escherichia coli.

Main Results:

• The designed multi-epitope vaccine is stable, with a molecular weight of 45 kDa and an antigenicity score of 0.936.
• Structural analysis indicated 23.49% alpha helix content and 90.5% residues in favored regions.
• Molecular docking demonstrated successful binding of the vaccine's interleukin-8 domain to its receptor with a low energy of -1020.9.

Conclusions:

• The designed multi-epitope vaccine is a computationally validated, stable, and potentially effective candidate for preventing Streptococcus Iniae infection in fish.
• This approach highlights the potential of bioinformatics in developing next-generation vaccines for aquaculture.
• Further experimental validation is warranted to confirm the vaccine's efficacy in vivo.