An In Silico Identification of Common Putative Vaccine Candidates against Treponema pallidum: A Reverse Vaccinology and Subtractive Genomics Based Approach

Abstract

Sexually transmitted infections (STIs) are caused by a wide variety of bacteria, viruses, and parasites that are transmitted from one person to another primarily by vaginal, anal, or oral sexual contact. Syphilis is a serious disease caused by a sexually transmitted infection. Syphilis is caused by the bacterium Treponema pallidum subspecies pallidum. Treponema pallidum (T. pallidum) is a motile, gram-negative spirochete, which can be transmitted both sexually and from mother to child, and can invade virtually any organ or structure in the human body. The current worldwide prevalence of syphilis emphasizes the need for continued preventive measures and strategies. Unfortunately, effective measures are limited. In this study, we focus on the identification of vaccine targets and putative drugs against syphilis disease using reverse vaccinology and subtractive genomics. We compared 13 strains of T. pallidum using T. pallidum Nichols as the reference genome. Using an in silicoapproach, four pathogenic islands were detected in the genome of T. pallidum Nichols. We identified 15 putative antigenic proteins and sixdrug targets through reverse vaccinology and subtractive genomics, respectively, which can be used as candidate therapeutic targets in the future.

Current progress of immunoinformatics approach harnessed for cellular- and antibody-dependent vaccine design

“…The advances in immunoinformatics technology have changed the face of current medical research. Currently, this technology has widely been used for the evaluation of epitopes for constructing chimeric multi-epitope vaccine for various organisms including Hepatitis B Virus [40] or Escherichia coli [41], Dengue [42], Schistosoma haematobium [43], Treponema pallidum [44], Staphylococcus aureus [45] and Trypanosoma cruzi [46]. The feasibility and low cost enable the mapping of B-and T-cell epitopes of A-C pathogens that are available at the National Institute of Allergy and Infectious Diseases (NIAID) such as Bacillus anthracis (anthrax), Clostridium botulinum toxin (botulism), Variola major (small pox), rabies and influenza viruses.…”

Putative vaccine candidates and drug targets identified by reverse vaccinology and subtractive genomics approaches to controlHaemophilus ducreyi, the causative agent of chancroid

“…For the prediction of vaccine targets, we used the subtractive genome approach adapted from Jaiswal et al [28]. Firstly, we used the core genome, that consists of the pathogen essential genes, and then we performed BLASTp analyses and predicted the non-host homologous targets.…”

“…After applying GIPSy analysis and predicting three pathogenicity islands, we plotted the results in figure 2, using BRIG software [61]. Pathogenicity island prediction is very important for the knowledge about the virulence factors encoded and their mobility and structure, in understanding the bacterial evolution and the interactions between pathogen and eukaryotic host cells [28], thus these PAI host virulence factors that may be desirable vaccine candidates and elicit an immune response.…”

The pan-genome of Treponema pallidum reveals differences in genome plasticity between subspecies related to venereal and non-venereal syphilis

“…Syphilis has a worldwide distribution (e.g. Africa has a high incidence), affecting every country and continent except perhaps Antarctica [8][9][10][11][12]. The stages of syphilis have been divided on the basis of clinical findings that lead to treatment and follow-up.…”