Ardestani Hassan, Nazarian Shahram, Hajizadeh Abbas, Sadeghi Davoud, Kordbacheh Emad
Department of Biological Sciences, Faculty of Science, Imam Hossein University, Tehran, Iran.
Department of Biological Sciences, Faculty of Science, Imam Hossein University, Tehran, Iran.
Mol Immunol. 2022 Apr;144:96-105. doi: 10.1016/j.molimm.2022.02.013. Epub 2022 Feb 23.
Stress or Heat Shock Proteins (HSPs) have been included in various operations like protein folding, autophagy, and apoptosis. HSP families recognize as protective antigens in a wide range of bacteria because they have been conserved through evolution. Due to their homology as well as antigenicity they are competent for applying in cross-protection against bacterial diseases.
In the present study, bioinformatics approaches utilized to design epitope-based construction of Hsp60 (or GroEL) protein. In this regard, potential B-cell and T-cell epitopes except for allergenic sequences were selected by immunoinformatic tools. The structural and functional aspects of the DNA, RNA, and protein levels were assessed by bioinformatics software. Following in silico investigations, recombinant GroEL multi-epitope of Salmonella typhi was expressed, purified, and validated. Mouse groups were immunized with recombinant protein and humoral immune response was measured by enzyme linked immunosorbent assay (ELISA). Animal challenge against Salmonella Typhimurium, Shigella flexneri, and Shigella dysenteriae was evaluated.
recombinant protein expression and purification with 14.3 kilodaltons (kDa) was confirmed by SDS-PAGE and western blotting. After animal administration, the immunoglobulins evaluated increase after each immunization. Immunized antisera exhibited 80%, 40%, and 40% protection against the lethal dose infection by S. Typhimurium, S. flexneri, and S. dysenteriae respectively. Passive immunization conferred 50%, 30%, and 30% protection in mice against S. Typhimurium, S. flexneri and S. dysentery respectively. In addition, bacterial organ load had exhibited a significant decrease in colony forming unit (CFU) in the liver and spleen of the immunized mice compared to the control.
Our study demonstrates the efficacy of S. Typhi recombinant GroEL multi-epitope to consider as a universal immunogen candidate versus multiple bacterial pathogens.
应激或热休克蛋白（HSPs）参与蛋白质折叠、自噬和凋亡等多种生理过程。HSP家族在多种细菌中被视为保护性抗原，因为它们在进化过程中得以保留。由于它们的同源性和抗原性，它们可用于针对细菌性疾病的交叉保护。
在本研究中，利用生物信息学方法设计基于表位的Hsp60（或GroEL）蛋白构建体。为此，通过免疫信息学工具选择除致敏序列外的潜在B细胞和T细胞表位。利用生物信息学软件评估DNA、RNA和蛋白质水平的结构和功能方面。经过计算机模拟研究后，表达、纯化并验证了伤寒沙门氏菌的重组GroEL多表位。用重组蛋白免疫小鼠组，并通过酶联免疫吸附测定（ELISA）测量体液免疫反应。评估动物对鼠伤寒沙门氏菌、福氏志贺氏菌和痢疾志贺氏菌的攻击情况。
通过SDS-PAGE和蛋白质印迹法确认了重组蛋白的表达和纯化，其分子量为14.3千道尔顿（kDa）。动物给药后，每次免疫后评估的免疫球蛋白均增加。免疫血清对鼠伤寒沙门氏菌、福氏志贺氏菌和痢疾志贺氏菌致死剂量感染的保护率分别为80%、40%和40%。被动免疫分别为小鼠提供了50%、30%和30%的针对鼠伤寒沙门氏菌、福氏志贺氏菌和痢疾的保护。此外，与对照组相比，免疫小鼠肝脏和脾脏中的细菌器官负荷在菌落形成单位（CFU）方面显著降低。
我们的研究证明了伤寒沙门氏菌重组GroEL多表位作为针对多种细菌病原体的通用免疫原候选物的有效性。
