Shetty Seema, Dash Swagatika, Kumar Avinash, Vishwanath Shashidhar, Kini Suvarna G, Brand Angela
Department of Microbiology, Kasturba Medical College, Manipal,, Manipal Academy of Higher Education, Madhav Nagar, Manipal, Karnataka, 576104, India.
Faculty of Health, Medicine and Life Sciences, Maastricht University, 6229 GT, Maastricht, The Netherlands.
Sci Rep. 2024 Dec 2;14(1):29919. doi: 10.1038/s41598-024-81736-w.
Chlamydia trachomatis (CT) remains a significant infectious cause of blindness and sexually transmitted infections worldwide. The objective and novelty of this study lie in using different serovars of CT to design a broad-spectrum multi-epitope vaccine that might confer immunity against different CT infections. As the major outer membrane protein in CT has good immunodominance properties and high conservation and also determines the several serotypes of CT, it is selected as an antibody target in this study. T-cell and B-cell epitopes from serovars A, B, D, E, L1, and L2 were predicted and combined into a single construct by incorporating adjuvants and linkers to enhance immunogenicity and stability. Physicochemical characterization confirmed the constructed vaccine's anti-allergic, immunogenicity, and thermostable characteristics, followed by structural modeling to refine its 3D configuration. The 3D model structure of the vaccine was validated through the Ramachandran plot and ProSA z-score. Molecular docking studies of the vaccine demonstrated stable binding with toll-like receptor 3, along with molecular dynamics simulations and binding free energy calculations supporting the complex's stability. In silico cloning has indicated a high potential for expression in Escherichia coli. Lastly, immune simulations revealed robust activation of B cells, cytotoxic T cells, and antigen-presenting cells, alongside significant production of IgM, IgG antibodies, and balanced Th1/Th2 cytokine response, which is crucial for effective immunity. These results suggest the multi-epitope vaccine could effectively induce comprehensive immune responses against CT, highlighting the need for further in vivo validation to advance this promising candidate toward clinical use.
沙眼衣原体(CT)仍是全球范围内导致失明和性传播感染的重要传染源。本研究的目的和创新之处在于利用不同血清型的CT设计一种广谱多表位疫苗,该疫苗可能对不同的CT感染产生免疫作用。由于CT中的主要外膜蛋白具有良好的免疫显性特性和高度保守性,并且决定了CT的几种血清型,因此在本研究中被选为抗体靶点。对血清型A、B、D、E、L1和L2的T细胞和B细胞表位进行了预测,并通过加入佐剂和连接子将其组合成一个单一的构建体,以增强免疫原性和稳定性。理化特性鉴定证实了所构建疫苗的抗过敏、免疫原性和热稳定特性,随后进行结构建模以优化其三维构型。通过拉氏图和ProSA z评分对疫苗的三维模型结构进行了验证。疫苗的分子对接研究表明其与Toll样受体3稳定结合,分子动力学模拟和结合自由能计算也支持该复合物的稳定性。电子克隆表明该疫苗在大肠杆菌中具有较高的表达潜力。最后,免疫模拟显示B细胞、细胞毒性T细胞和抗原呈递细胞被强烈激活,同时大量产生IgM、IgG抗体,Th1/Th2细胞因子反应平衡,这对有效免疫至关重要。这些结果表明,该多表位疫苗可有效诱导针对CT的全面免疫反应,突出了进一步进行体内验证的必要性,以便将这一有前景的候选疫苗推进到临床应用阶段。