Genome-Wide Prediction of Potential Vaccine Candidates for Campylobacter jejuni Using Reverse Vaccinology

Abstract

Campylobacteriosis is a deadly disease which has developed resistance to most of the available chemotherapeutic agents. Although various studies provide evidence of acquired immunity following exposure to Campylobacter jejuni, no effective vaccine has been developed, still. Hence, there is an urgent need to identify potential vaccine candidates for Campylobacter species. In the proposed study, Campylobacter jejuni subsp. jejuni serotype O:2 (strain NCTC 11168) was taken and computational approach was employed to screen C. jejuni genome for promising vaccine candidates. From 1623 protein-coding sequences, 37 potential antigens were screened for epitope prediction based on surface association, consensus antigenicity predictions, solubility, transmembrane domain, and ortholog analysis. Comprehensive immunogenic analysis of these 37 antigens revealed that antigen Q0PA22 shows the greatest potential for experimental immunogenicity analysis. It has several potential CD4+ and CD8+ T-cell epitopes, as well as high probability of B-cell epitope regions as compared to well-characterized antigen Omp18 (Uniprot ID:Q0PC24). Among the highest scoring predicted epitopes, an optimal set of epitopes with respect to overall immunogenicity in target populations for campylobacteriosis viz. Europe, North America and Southwest Asia was determined. An epitope AMLTYMQWL from antigen no. 6(Q0PA22) binds to the most prevalent allele HLA-A*0201, and this epitope has most immunogenicity for all the target populations. In addition, this epitope exhibited highly significant TCR-pMHC interactions having a joint Z value of 4.87. Homology mapping studies of the predicted epitope show best homology to a well-studied antigenic peptide from influenza virus H5N1. Therefore, the predicted epitope might be a suitable vaccine candidate.

A proteome-wide screen of Campylobacter jejuni using protein microarrays identifies novel and conformational antigens

“…jejuni infection [45], including CjaA and five novel antigens: Cj0144, Cj0262c, Cj1621, GreA, and PrfA (Table 1). Three of these new antigens are predicted to have transmembrane domains (Cj0144, Cj0262c, and Cj1621) and none of them were among the proteins previously predicted to be immunogenic or vaccine candidates based on sequence features [25, 28].…”

“…Several candidate antigens have been identified and further studied based on their predicted properties such as localization to the outer membrane or secreted fractions [16, 18–23]. Individual candidate immunogens for vaccines have also been identified based on prediction algorithms that screen global protein sequences for localization signals, antigenicity, homology, and other properties [24–28]. While some of the proteins predicted by these algorithms have been identified as immunogens in other screens, most have not been directly tested yet.…”

Vaccine candidate designed against carcinoembryonic antigen-related cell adhesion molecules using immunoinformatics tools

“…Note that the predicted probability of antigenicity score is between 0 and 1, where a higher value indicates a greater likelihood that the input sequence is antigenic. The antigenicity score obtained for this vaccine highlights its antigenic nature and this value exceeds the desired antigenicity value threshold of a 0.6 (Jain et al, 2019).…”

Advancements In Developing Anti-Campylobacter Vaccine For Poultry

“…W ostatnich latach nastąpił znaczny rozwój narzędzi umożliwiających wydajną analizę in silico. Badania immunoinformatyczne proteomu Campylobacter przeprowadzone w 2017 roku doprowadziły do identyfikacji kilku epitopów, które są konserwowane, prezentowane przez cząsteczki MHC-I i potencjalnie mogą zostać wykorzystane w opracowywaniu szczepionki chroniącej przed kampylobakteriozą [42,59]. Ich użyteczność musi zostać jednak potwierdzona eksperymentalnie.…”