Laboratory of Microbiology and Immunology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka City, Shizuoka, 422-8526, Japan.
Laboratory of Plant Molecular Improvement, Graduate Division of Nutritional and Environmental Sciences, University of Shizuoka, Shizuoka City, Shizuoka, 422-8526, Japan.
Plant Cell Rep. 2019 Feb;38(2):161-172. doi: 10.1007/s00299-018-2358-6. Epub 2018 Nov 30.
A key module, secretory component (SC), was efficiently expressed in Arabidopsis thaliana. The plant-based SC and immunoglobulin A of animal or plant origin formed secretory IgA that maintains antigen-binding activity. Plant expression systems are suitable for scalable and cost-effective production of biologics. Secretory immunoglobulin A (SIgA) will be useful as a therapeutic antibody against mucosal pathogens. SIgA is equipped with a secretory component (SC), which assists the performance of SIgA on the mucosal surface. Here we produced SC using a plant expression system and formed SIgA with dimeric IgAs produced by mouse cells as well as by whole plants. To increase the expression level, an endoplasmic reticulum retention signal peptide, KDEL (Lys-Asp-Glu-Leu), was added to mouse SC (SC-KDEL). The SC-KDEL cDNA was inserted into a binary vector with a translational enhancer and an efficient terminator. The SC-KDEL transgenic Arabidopsis thaliana produced SC-KDEL at the level of 2.7% of total leaf proteins. In vitro reaction of the plant-derived SC-KDEL with mouse dimeric monoclonal IgAs resulted in the formation of SIgA. When reacted with Shiga toxin 1 (Stx1)-specific ones, the antigen-binding activity was maintained. When an A. thaliana plant expressing SC-KDEL was crossed with one expressing dimeric IgA specific for Stx1, the plant-based SIgA exhibited antigen-binding activity. Leaf extracts of the crossbred transgenic plants neutralized Stx1 cytotoxicity against Stx1-sensitive cells. These results suggest that transgenic plants expressing SC-KDEL will provide a versatile means of SIgA production.
一个关键模块，分泌成分 (SC)，在拟南芥中得到了高效表达。植物来源的 SC 和动物或植物来源的免疫球蛋白 A 形成了具有抗原结合活性的分泌型 IgA。植物表达系统适合于生物制剂的可扩展和具有成本效益的生产。分泌型免疫球蛋白 A（SIgA）将作为针对粘膜病原体的治疗性抗体很有用。SIgA 配备有分泌成分（SC），它有助于 SIgA 在粘膜表面上的表现。在这里，我们使用植物表达系统生产 SC，并与由小鼠细胞以及整个植物产生的二聚体 IgA 形成 SIgA。为了提高表达水平，将内质网保留信号肽 KDEL（Lys-Asp-Glu-Leu）添加到小鼠 SC（SC-KDEL）中。SC-KDEL cDNA 被插入带有翻译增强子和高效终止子的二元载体中。SC-KDEL 转基因拟南芥以总叶片蛋白的 2.7%的水平产生 SC-KDEL。植物来源的 SC-KDEL 与小鼠二聚单克隆 IgA 的体外反应导致 SIgA 的形成。当与志贺毒素 1（Stx1）特异性的 ones 反应时，保持了抗原结合活性。当表达 SC-KDEL 的拟南芥植物与表达针对 Stx1 的二聚 IgA 的植物杂交时，基于植物的 SIgA 表现出抗原结合活性。表达 SC-KDEL 的杂交转基因植物的叶片提取物中和了针对 Stx1 敏感细胞的 Stx1 细胞毒性。这些结果表明，表达 SC-KDEL 的转基因植物将提供一种通用的 SIgA 生产方法。
