Cj0983 and Cj0090 Lipoproteins Contain Potential Linear Peptide Epitopes for Anti-Campylobacter jejuni Vaccine Applications

Campylobacter jejuni, a Gram-negative bacterium, is the major etiologic agent of campylobacteriosis responsible for approximately 90% of reported foodborne infections globally. As a result, alternative approaches such as bacterial vaccines may play pivotal roles in mitigating these bacterial public health concerns. Although there are ongoing studies on the development of vaccine candidates based on antigenic molecules of C. jejuni, the potential of Cj0983 and Cj0090 to be independently considered in the preparation of a protective lipoprotein antigen-based anti-C. jejuni vaccine remains elusive. Herein, the potential linear antigenic epitopes in Cj0983 and Cj0090 from C. jejuni were investigated for possible vaccine applications. Linear peptide epitopes were identified and evaluated for their antigenic and non-allergenic properties using VaxiJen and AllergenFP, respectively. Comprehensive bioinformatics-based in silico analyses revealed that there were 37 B-cell, 371 Class I T-cell, and 365 Class II T-cell peptide epitopes found in Cj0983. In comparison, there were 10 B-cell, 63 Class I T-cell, and 93 Class II T-cell peptide epitopes found in Cj0090. Through PyMOL, selected molecular interactions were screened and predicted between chains of human leukocyte antigen (HLA)-peptide epitope complexes, revealing that H-bonding is the predominant intermolecular force during binding. Our results identified the top three peptide epitopes for Cj0983 (312QNDDYKLNLDLKFKN326, 311TQNDDYKLNLDLKFK325, and 309NITQNDDYKLNLDLKF324) and Cj0090 (98QEVILRKLASDTRAND113, 106ASDTRANDFRLEIKA120, and 113DFRLEIKAK121) which have great potentials as vaccine components and can further be utilized as contributing protein-derived molecules towards advancing anti-C. jejuni vaccine development.