Development of multiepitope subunit protein vaccines against Toxoplasma gondii using an immunoinformatics approach

Abstract

<jats:title>Abstract</jats:title> <jats:p>Approximately one-third of the world’s human population is estimated to have been exposed to the parasite Toxoplasma gondii. Its prevalence is reportedly high in Ethiopia (74.80%) and Zimbabwe (68.58%), and is 40.40% in Nigeria. The adverse effect of this parasite includes a serious congenital disease in the developing fetus of pregnant women. After several efforts to eliminate the disease, only one licensed vaccine ‘Toxovax’ has been used to avoid congenital infections in sheep. The vaccine has been adjudged expensive coupled with adverse effects and short shelf life. The potential of vaccine to likely revert to virulent strain is a major reason why it has not been found suitable for human use, hence the need for a vaccine that will induce T and B memory cells capable of eliciting longtime immunity against the infection. This study presents immunoinformatics approaches to design a T. gondii-oriented multiepitope subunit vaccine with focus on micronemal proteins for the vaccine construct. The designed vaccine was subjected to antigenicity, immunogenicity, allergenicity and physicochemical parameter analyses. A 657-amino acid multiepitope vaccine was designed with the antigenicity probability of 0.803. The vaccine construct was classified as stable, non-allergenic, and highly immunogenic, thereby indicating the safety of the vaccine construct for human use.</jats:p>

Screening of apical membrane antigen-1 (AMA1), dense granule protein-7 (GRA7) and rhoptry protein-16 (ROP16) antigens for a potential vaccine candidate against Toxoplasma gondii for chickens

“…The addition of T. gondii profilin to the vaccine serves a crucial role since profilin is a protein known to function as a critical ligand recognised by receptors such as TLR11 and TLR2, crucial for activating host immune response via Th1 adaptive response during a parasite-host invasion [2] . Adding these linkers and an adjuvant to the vaccine construct aided in the flexibility and improved stability of the tertiary structure or model of the proposed vaccine, while the adjuvant enhanced the immunogenicity of the designed vaccine [22] .…”

“…Various research has focused on different antigens found in the parasite to develop a peptide-based vaccine against T. gondii , namely, dense granule proteins, microneme proteins, rhoptry proteins and surface antigens and apical membrane antigens [17] , [18] , [19] , [20] . Research works focusing on T. gondii antigens as alternative control strategies through vaccination have been previously implemented, verifying the importance of improved control measures to alleviate toxoplasmosis [17] , [21] , [22] , [23] , [24] .…”

Toxoplasmosis vaccines: what we have and where to go?

“…The subunit vaccines with multiple epitope designs are more valuable for research. Onile et al used immune informatics tools to design multi-epitope subunit vaccines with different T-cell and B-cell epitopes to fight toxoplasmosis 14 . Two recombinant proteins, recombinant rhoptry protein 18 (rROP18) and recombinant calcium-dependent protein kinase 6 (rCDPK6), combined with Poly (lactide-co-glycolide) (PLG), a biodegradable and biocompatible polymer, prolong the protein release period, lower protein degradation and induce a long-lasting immune response.…”

In silico design of a promiscuous chimeric multi-epitope vaccine against Mycobacterium tuberculosis

“…Currently, multi-epitope vaccines have been designed against many pathogenic microorganisms, including Shigella spp. [19] , foot-and-mouth disease virus [20] , Helicobacter pylori [21] , [22] , hepatitis B virus [23] , Toxoplasma gondii [24] , Leishmania infantum [25] , Nipah virus [26] , Onchocerca volvulus [27] , Pseudomonas aeruginosa [28] , and leukosis virus [29] . In particular, the emergence of the COVID-19 pandemic has strengthened the application of this technology [16] , [30] , [31] , [32] .…”