In Silico Vaccine Design for Multidrug-Resistant Staphylococcus Aureus Clumping Factor A (ClfA)

Staphylococcus aureus a facultative anaerobic multidrug-resistant bacterium can cause a range of illnesses, from minor skin infections, such as pimples, boils, impetigo, folliculitis, cellulitis, carbuncles, scalded skin syndrome, and abscesses and life-threatening diseases such as meningitis, pneumonia, bacteremia, sepsis, osteomyelitis, endocarditis and toxic shock syndrome. Pathogenic strains often promote infections by producing virulence factors and the expression of cell-surface proteins that bind and inactivate antibodies. The emergence of antibiotic-resistant strains of S. aureus such as methicillin resistant S. aureus (MRSA) is a worldwide problem in clinical medicine. In spite of immense research and development, not much progress has been made with regard to an epitope based vaccine and till date there is no approved vaccine for S. aureus. This study aims to analyze and predict the possibility of designing a vaccine that could make humans immune to S. aureus. The surface protein ClfA is highly antigenic among the virulence factors of S. aureus which act as an adhesin often essential for infection was collected from a protein database and in silico tools were used to predict the T-cell epitopes by NetCTL 1.2 and B-cell epitopes by Bepipred from IEDB (Immune Epitope Database). Further, MHC Class I and Class II binding peptides were predicted using TepiTool from IEDB analysis resource. The peptide KPNTDSNAL was found as the most potential B-cell and T-cell epitope. The epitope was further tested for binding against the HLA molecule by computational docking techniques to verify the HLA and epitope interaction. However, the in silico designed epitope-based peptide vaccine against S. aureus need to be validated by in vitro and in vivo experiments