Imaizumi Kentaro, Phurahong Thararat, Siripattanapipong Suradej, Choowongkomon Kiattawee, Leelayoova Saovanee, Mungthin Mathirut, E-Kobon Teerasak, Unajak Sasimanas
Department of Biochemistry, Faculty of Science, Kasetsart University, 50 Ngam Wong Wan, Chatuchak, Bangkok 10900, Thailand.
Kasetsart Vaccine and Bio-Product Innovation Centre, Kasetsart University, 50 Ngam Wong Wan, Chatuchak, Bangkok 10900, Thailand.
Biology (Basel). 2022 Oct 5;11(10):1460. doi: 10.3390/biology11101460.
Leishmaniasis is a parasitic disease caused by protozoan flagellates of the genus . Recently, and , emerging species of , were isolated from patients in Thailand. Development of the vaccine is demanded; however, genetic differences between the two species make it difficult to design a vaccine that is effective for both species. In this study, we applied immuno-informatic approaches to design a chimeric multi-epitope vaccine (CMEV) against both and . We identified seven helper T lymphocyte (HTL) epitopes, sixteen cytotoxic T lymphocyte (CTL) epitopes, and eleven B-cell epitopes from sixteen conserved antigenic proteins found in both species. All these epitopes were joined together, and to further enhance immunogenicity, protein and peptides adjuvant were also added at the N-terminal of the molecule by using specific linkers. The candidate CMEV was subsequently analyzed from the perspectives of the antigenicity, allergenicity, and physiochemical properties. The interaction of the designed multi-epitope vaccine and immune receptor (TLR4) of the host were evaluated based on molecular dockings of the predicted 3D structures. Finally, in silico cloning was performed to construct the expression vaccine vector. Docking analysis showed that the vaccine/TLR4 complex took a stable form. Based on the predicted immunogenicity, physicochemical, and structural properties in silico, the vaccine candidate was expected to be appropriately expressed in bacterial expression systems and show the potential to induce a host immune response. This study proposes the experimental validation of the efficacy of the candidate vaccine construct against the two .
利什曼病是由利什曼原虫属的原生动物鞭毛虫引起的一种寄生虫病。最近，从泰国患者中分离出了利什曼原虫属的新兴物种——杜氏利什曼原虫和婴儿利什曼原虫。疫苗的研发迫在眉睫；然而，这两个物种之间的基因差异使得设计一种对两者都有效的疫苗变得困难。在本研究中，我们应用免疫信息学方法设计了一种针对杜氏利什曼原虫和婴儿利什曼原虫的嵌合多表位疫苗（CMEV）。我们从这两个物种中发现的16种保守抗原蛋白中鉴定出7个辅助性T淋巴细胞（HTL）表位、16个细胞毒性T淋巴细胞（CTL）表位和11个B细胞表位。所有这些表位都连接在一起，为进一步增强免疫原性，还通过使用特定接头在分子的N端添加了蛋白质和肽佐剂。随后从抗原性、致敏性和理化性质等方面对候选CMEV进行了分析。基于预测的三维结构的分子对接，评估了设计的多表位疫苗与宿主免疫受体（TLR4）的相互作用。最后，进行了电子克隆以构建表达疫苗载体。对接分析表明疫苗/TLR4复合物呈稳定形式。基于电子预测的免疫原性、理化和结构性质，预计该候选疫苗在细菌表达系统中能适当表达，并具有诱导宿主免疫反应的潜力。本研究提出对候选疫苗构建体针对这两种利什曼原虫的疗效进行实验验证。
