Analysis of outer membrane protein from Orientia tsutsugamushi for epitope mining

Scrub typhus, caused by <i>Orientia tsutsugamushi</i>, is an emerging health threat that can lead to severe complications if untreated. Therefore, it is of interest to analyse 130 sequences of the 56 kDa outer membrane protein, a key immunodominant antigen. SNP profiling identified 300 conserved and 8 highly variable residues. Epitope prediction revealed 73 conserved and 6 variable B cell epitopes, along with 4 conserved and 1 variable CD8⁺ T cell epitopes and 3 conserved and 1 variable CD4⁺ T cell epitopes. Notably, five immunogenic regions were predicted to activate B cells and both CD8⁺ and CD4⁺ T cells simultaneously. Thus, we show valuable insight into immune recognition and evasion strategies of <i>O. tsutsugamushi</i>. Subject to experimental validation, the identified epitopes represent promising candidates for rational vaccine development, improved serodiagnostics and novel therapeutic interventions against scrub typhus.