Xinjiang Key Laboratory of Biological Resources and Genetic Engineering, College of Life Science and Technology, Xinjiang University, Urumqi 830046, China.
Xinjiang Key Laboratory of Biological Resources and Genetic Engineering, College of Life Science and Technology, Xinjiang University, Urumqi 830046, China.
Int J Biol Macromol. 2022 Nov 1;220:638-658. doi: 10.1016/j.ijbiomac.2022.08.072. Epub 2022 Aug 14.
The study aims to investigate the constituents, adjuvant effects, and underlying mechanisms of purified polysaccharides from cultivated Cistanche deserticola (C. deserticola). Two macromolecules designated as CCDP-1 (26.5 kDa) and CCDP-2 (32.3 kDa) from C. deserticola were respectively identified as carbohydrate-lignin complexes with 44.1 % and 43.8 % lignin. CCDP-1 and CCDP-2 were composed of glucose, rhamnose, galactose, arabinose, and mannose respectively in the molar ratios of 7.22: 5.98:2.51:1.81:1.00 and 6.57:8.48:4.20:2.72:1.00. An in vitro experiment revealed that endotoxin-free CCDP-1 and CCDP-2 promoted splenocyte proliferation without cytotoxicity, but CCDP-2 induced dendritic cell (DC) maturation more efficiently than CCDP-1. An in vivo experiment suggested that CCDP-2 enhanced OVA-specific antibody production, antigen-specific T-cell activation, IFN-γ production, IL-4 production, and DC activation. Notably, CCDP-2 elicited a Th1-biased response. Mechanically, CCDP-2 upregulated CD40, CD80, CD86, and MHC II, facilitated allogeneic T-cell proliferation and Th1/Th2 cytokines, improved IFN-γ, IL-12, IL-6, and TNF-α production, and decreased endocytosis from DCs in vitro. Blocking assays indicated that TLR2 and TLR4 were the membrane receptor candidates of DCs. Western blot implied that CCDP-2 with the immune-enhancing activities were involved in the activation of MAPKs and NF-κB pathways in a dose-/time-related manner and could be employed as a more balanced Th1/Th2 adjuvant for vaccine exploitation.
本研究旨在探究栽培管花肉苁蓉（Cistanche deserticola）中纯化多糖的成分、佐剂效应及其潜在机制。从管花肉苁蓉中分离得到两种大分子物质，分别命名为 CCDP-1（26.5 kDa）和 CCDP-2（32.3 kDa），它们是碳水化合物-木质素复合物，其木质素含量分别为 44.1%和 43.8%。CCDP-1 和 CCDP-2 分别由葡萄糖、鼠李糖、半乳糖、阿拉伯糖和甘露糖组成，摩尔比分别为 7.22:5.98:2.51:1.81:1.00 和 6.57:8.48:4.20:2.72:1.00。体外实验表明，无内毒素的 CCDP-1 和 CCDP-2 可促进脾细胞增殖，无细胞毒性，但 CCDP-2 诱导树突状细胞（DC）成熟的效率高于 CCDP-1。体内实验表明，CCDP-2 增强了 OVA 特异性抗体的产生、抗原特异性 T 细胞的激活、IFN-γ 的产生、IL-4 的产生和 DC 的激活。值得注意的是，CCDP-2 引发了 Th1 偏向的反应。在机制上，CCDP-2 上调了 CD40、CD80、CD86 和 MHC II，促进了同种异体 T 细胞的增殖和 Th1/Th2 细胞因子的产生，提高了 IFN-γ、IL-12、IL-6 和 TNF-α的产生，并降低了 DC 的内吞作用。阻断实验表明，TLR2 和 TLR4 是 DC 膜受体候选物。Western blot 表明，具有免疫增强活性的 CCDP-2 以剂量和时间相关的方式激活了 MAPKs 和 NF-κB 通路，可作为一种更平衡的 Th1/Th2 佐剂用于疫苗开发。
