Bioinformatics Analysis to Designing a Multi-epitope-based Peptide Vaccine Combat Leishmania major

Background and Aim: Cutaneous leishmaniasis is a significant public health issue worldwide. Cutaneous leishmaniasis is the most prevalent in the world among the different types of leishmaniasis. Currently, available medications have had no discernible influence on the disease's progression. Up to now, there has been no approved cutaneous leishmaniasis vaccine. New developments in vaccination might be a potential way to come up with a vaccination that is successful for the treatment of cutaneous leishmaniasis. Materials and Methods: This research was conducted to learn more about an effective vaccine for Leishmania major , the ailment's primary cause of CL, which was designed using computational methods. Thus, a multiepitope protein was designed by utilizing potential immune system epitopes, including predicted MHC class I, MHC class II, Cytotoxic T lymphocytes, B-cell, and Interferon-gamma epitopes of Cysteine protease b (CPB), Leishmania homologue of activated C kinase (LACK), and Kinetoplastid membrane protein-11 (KMP-11) antigenic proteins. In order to enhance vaccine immunogenicity, two resuscitation-promoting factors of Mycobacterium tuberculosis were used as adjuvants. Final epitopes were matched with suitable linkers to construct the recombinant structure. The physicochemical and immune-based characteristics of the designed vaccine have been forecasted by using different tools. Moreover, homogeneity modeling was performed to obtain a high-quality 3D structure, followed by refinement and validation. Finally, the codon optimization based on E. coli resulted in a higher CAI value and optimal GC content, followed by combining it in the pET-14b cloning vector. Results: Evaluation of the various characteristics of the designed vaccine showed that it is an immunogenic and non-allergenic antigen that can induce immune responses against Leishmania major infection, which could be promising for cutaneous leishmaniasis. Conclusion: Research shows that a recombinant vaccine can be an effective candidate against cutaneous leishmaniasis.