# Design of Innovative Divalent Cj1621 and CjaA Multiepitope mRNA-Based Vaccine Against Foodborne Campylobacter jejuni Using In Silico Approaches

## TL;DR

This study designs a new mRNA-based vaccine against Campylobacter jejuni using computational methods to target two key proteins and stimulate immune responses.

## Contribution

A novel multiepitope mRNA vaccine candidate is proposed using in silico approaches for foodborne C. jejuni.

## Key findings

- The vaccine construct is immunogenic, nontoxic, and stable based on physiochemical and structural evaluations.
- Docking analysis shows stable interactions with immune receptors TLR-2, TLR-4, B7-1, and B7-2.
- The vaccine is predicted to induce both humoral and cellular immunity in the host.

## Abstract

Campylobacter jejuni is one of the main causes of gastroenteritis in human and animals worldwide. Emergence of antibiotic resistance in microorganisms increased the need to develop new types of vaccines. The present study aimed to design novel multiepitope mRNA vaccine against Campylobacter jejuni using immunoinformatics tools. For this purpose, two virulence C. jejuni proteins (Cj1621 and CjaA) were selected as antigen targets, and the appropriate epitopes were predicted using immunoinformatics tools and molecular models. Five cytotoxic T lymphocyte, six helper T lymphocyte, four linear B-cell, and one conformational B-cell epitopes were linked together with an appropriate linker, and then, adjuvant (RpfE) was attached to the construct candidate. Physiochemical, immunological, secondary, and 3D structure evaluation of the proposed vaccine showed it is immunogenic, nontoxic, nonallergic, flexible, and stable. Furthermore, docking shows that the vaccine has stable interaction with the immune receptors TLR (TLR-2 and TLR-4) and B7 (B7-1 and B7-2). Moreover, analysis of the vaccine with the MD server shows its ability to induce humoral and cellular immunity of the selected host. Overall, our findings indicate that the proposed vaccine could be a promising option against Campylobacter jejuni infection; however, further lab-based studies are needed to confirm the efficiency and safety of this vaccine.