Comparative Analysis of the CadF Protein as a Broad-Spectrum Vaccine Target in Four Campylobacter Species

Campylobacter species are Gram-negative bacteria frequently detected in poultry and poultry-processing environments, making contaminated food a leading source of campylobacteriosis. This illness is typically characterized by diarrhea, abdominal cramps, nausea, and mild-to-severe fever, lasting for several days. The most common species infecting humans include C. jejuni, C. coli, C. hyointestinalis, and C. fetus. Rising antimicrobial resistance in Campylobacter strains has created challenges for treatment and control in both clinical and industrial settings, emphasizing the importance of vaccination, involving host immune stimulation, as a promising preventive strategy. This study focuses on Campylobacter adhesin to fibronectin protein (CadF), an outer membrane fibronectin-binding protein essential for Campylobacter adherence and pathogenesis, as a potential vaccine target. Comparative analyses of CadF from the four abovementioned species were performed via amino acid sequence alignment, three-dimensional protein structure modeling, and prediction of B- and T-cell epitopes. The results demonstrated that CadF is highly conserved across these species, with multiple shared epitopes on surface-exposed regions. These findings suggest that CadF is a strong candidate target for a broad-spectrum vaccine to prevent Campylobacter infections in humans and potentially in animal reservoirs.