Motamedpour Leila, Dalimi Abdolhossein, Pirestani Majid, Ghaffarifar Fatemeh
Parasitology Department, Medical Sciences Faculty, Tarbiat Modares University, Tehran, Iran.
Iran J Basic Med Sci. 2020 Nov;23(11):1409-1418. doi: 10.22038/ijbms.2020.45394.10561.
Since leishmaniasis is one of the health problems in many countries, the development of preventive vaccines against it is a top priority. Peptide vaccines may be a new way to fight the Leishmania infection. In this study, a silicon method was used to predict and analyze B and T cells to produce a vaccine against cutaneous leishmaniasis.
Immunodominant epitope of were selected from four TSA, LPG3, GP63, and Lmsti1 antigens and linked together using a flexible linker (SAPGTP). The antigenic and allergenic features, 2D and 3D structures, and physicochemical features of a chimeric protein were predicted. Finally, through bioinformatics methods, the mRNA structure was predicted and was produced chemically and cloned into the pLEXY-neo2 vector.
Results indicated, polytope had no allergenic properties, but its antigenicity was estimated to be 0.92%. The amino acids numbers, molecular weight as well as negative and positive charge residuals were estimated 390, ~41KDa, 41, and 30, respectively. The results showed that the designed polytope has 50 post-translationally modified sites. Also, the secondary structure of the protein is composed of 25.38% alpha-helix, 12.31% extended strand, and 62.31% random coil. The results of SDS-PAGE and Western blotting revealed the recombinant protein with ~ 41 kDa. The results of Ramachandran plot showed that 96%, 2.7%, and 1.3% of amino acid residues were located in the preferred, permitted, and outlier areas, respectively.
It is expected that the TLGL polytope will produce a cellular immune response. Therefore, the polytope could be a good candidate for an anti-leishmanial vaccine.
由于利什曼病是许多国家面临的健康问题之一，因此开发针对它的预防性疫苗是当务之急。肽疫苗可能是对抗利什曼原虫感染的一种新方法。在本研究中，采用硅方法预测和分析B细胞和T细胞，以制备针对皮肤利什曼病的疫苗。
从四种TSA、LPG3、GP63和Lmsti1抗原中选择免疫显性表位，并使用柔性接头（SAPGTP）将它们连接在一起。预测了嵌合蛋白的抗原性和致敏性特征、二维和三维结构以及理化特征。最后，通过生物信息学方法预测mRNA结构，并进行化学合成，然后克隆到pLEXY-neo2载体中。
结果表明，多表位没有致敏特性，但其抗原性估计为0.92%。氨基酸数量、分子量以及正负电荷残基分别估计为390、约41 kDa、41和30。结果表明，设计的多表位有50个翻译后修饰位点。此外，该蛋白的二级结构由25.38%的α-螺旋、12.31%的延伸链和62.31%的无规卷曲组成。SDS-PAGE和蛋白质印迹结果显示重组蛋白约为41 kDa。拉氏图结果表明，分别有96%、2.7%和1.3%的氨基酸残基位于优选区、允许区和异常区。
预计TLGL多表位将产生细胞免疫反应。因此，该多表位可能是抗利什曼病疫苗的良好候选物。
