Institute of Physiology, Komi Science Center, Ural Branch of the Russian Academy of Sciences, 167982 Syktyvkar, Russia.
Biochemistry (Mosc). 2013 Jul;78(7):823-35. doi: 10.1134/S0006297913070134.
Pectins are the major component of plant cell walls, and they display diverse biological activities including immunomodulation. The pectin macromolecule contains fragments of linear and branched regions of polysaccharides such as homogalacturonan, rhamnogalacturonan-I, xylogalacturonan, and apiogalacturonan. These structural features determine the effect of pectins on the immune system. The backbones of pectic macromolecules have immunosuppressive activity. Pectins containing greater than 80% galacturonic acid residues were found to decrease macrophage activity and inhibit the delayed-type hypersensitivity reaction. Branched galacturonan fragments result in a biphasic immunomodulatory action. The branched region of pectins mediates both increased phagocytosis and antibody production. The fine structure of the galactan, arabinan, and apiogalacturonan side chains determines the stimulating interaction between pectin and immune cells. This review summarizes data regarding the relationship between the structure and immunomodulatory activity of pectins isolated from the plants of the European north of Russia and elucidates the concept of polypotency of pectins in native plant cell walls to both stimulate and suppress the immune response. The possible mechanisms of the immunostimulatory and anti-inflammatory effects of pectins are also discussed.
果胶是植物细胞壁的主要成分，具有多种生物活性，包括免疫调节作用。果胶大分子包含线性和支链多糖片段，如半乳糖醛酸聚糖、鼠李半乳糖醛酸聚糖 I、木半乳糖醛酸聚糖和-apiogalacturonan。这些结构特征决定了果胶对免疫系统的影响。果胶大分子的主链具有免疫抑制活性。含有大于 80%半乳糖醛酸残基的果胶被发现能降低巨噬细胞活性并抑制迟发型超敏反应。支链半乳糖醛酸片段导致双相免疫调节作用。果胶的支链区域介导吞噬作用和抗体产生的增加。半乳聚糖、阿拉伯聚糖和-apiogalacturonan 侧链的精细结构决定了果胶与免疫细胞之间的刺激相互作用。本文综述了俄罗斯北部植物中分离的果胶的结构与免疫调节活性之间的关系，并阐明了天然植物细胞壁中果胶的多效性概念，既能刺激又能抑制免疫反应。还讨论了果胶的免疫刺激和抗炎作用的可能机制。
