Design of synthetic Peptides as Vaccine candidates against Crimean Congo haemorrhagic fever virus

Abstract

Crimean-Congo hemorrhagic fever virus (CCHFV) is endemic in 30 nations of Asia, Europe, Middle East, and Africa, and has the widest geographic distribution among tick-borne virus diseases. Hyalomma marginatum ticks serves as primary vector of CCHFV. Three billion people are thought to be susceptible to CCHFV infection. In 1944, the first case of CCHFV was found in the Crimean area of Eastern Europe. Later in 1956, it was found in the Belgian Congo, and it was called as Crimean-Congo hemorrhagic fever (CCHF). CCHF has reported 140 cases in 52 countries around the world and resulted an endemic situation. In 2011, India witnessed first case of CCHF disease in Ahmedabad and in subsequent years cases in other regions of India have been documented (Rajasthan and Kerala). From 2011-2020, 125 cases and 53 deaths of CCHF infection have been documented in India. World health organization (WHO) has categorized CCHFV as high priority pathogen. No treatment or vaccines for CCHFV have been approved till date for human use. Therefore, there is a crucial need of CCHFV vaccination which can offer protection against all CCHFV strains. Vaccine candidates targeting conserved regions of CCHFV and capable of binding with diverse human leukocyte antigen (HLA) alleles could serve as potential candidates against CCHF disease. Considering these facts, this study is focused on selection of conserved CCHFV RNA segment aided mutation profiling, homology modelling and simulation study of L, M and S segment followed by prediction of conserved, antigenic peptides containing multiple B and T cells without any detrimental response (autoimmunity and allergenicity) using immunoinformatics approach. Identified peptides were evaluated for population coverage and binding affinity with HLA alleles and T cell receptor aided docking study. Best docked complexes were simulated for 50 ns to assess stability of HLA-peptide-TCR docked complexes using GROMACS v2021 software. Furthermore, identified peptides were commercially synthesized for evaluating