Department of Pharmacology and Toxicology, Faculty of Pharmaceutical Sciences, University of Nigeria, Nsukka, Nigeria.
Immunopharmacol Immunotoxicol. 2010 Sep;32(3):393-401. doi: 10.3109/08923970903463939.
Decoctions of Phyllanthus niruri (PN) (Fam. Euphorbiaceae) is promoted in traditional medicine of Africa, Asia, and South America as beneficial supplement for different infectious diseases, especially for viral hepatitis, tumor, and for immune compromised patients. This stimulated the interest in understanding the mechanisms by which the whole extract of the plant could stimulate the immune system. Dendritic cells (DCs) are professional antigen-presenting cells and provide a link between the innate and the adaptive immune responses. In the present study, the effects of lyophilized aqueous extract of PN on structural and functional maturation of murine bone marrow-derived DCs (BM-DCs) were investigated. Bone marrow cells were cultured in the presence of granulocyte macrophage-colony stimulating factor and interleukin-4 (IL-4) and the generated immature DCs were stimulated with PN (25, 50, and 100 microg/mL) or lipopolysaccharide (10 microg/mL) for 48 h. Results showed that treatment with PN increased the expression of major histocompatibility complex-II and the various makers for DCs maturation (CD40), activation (CD83), and costimulation (CD86) in a concentration-dependent manner. Consistent with the increase in phenotypic makers, functional maturation assay showed that treatment of BM-DCs with PN caused a decrease in fluorescein isothiocyanate-dextran pinocytosis and an increase in IL-12 in the supernatant. In a transgenic T-cell activation model, PN-treated BM-DCs presented Ova antigen to Ova-specific CD8(+) T cells from OT-1 mice more efficiently as demonstrated by increased T-cells proliferation and IL-2 production. Therefore, PN enhances the structural and functional maturation of BM-DCs and their antigen-presenting function. These effects are relevant in immunodeficient conditions, tumor control, and in infectious diseases.
水飞蓟宾（Phyllanthus niruri）（大戟科）的煎剂在非洲、亚洲和南美洲的传统医学中被推荐用于治疗各种传染病，特别是病毒性肝炎、肿瘤和免疫功能低下的患者。这激发了人们对理解植物全提取物如何刺激免疫系统的机制的兴趣。树突状细胞（DCs）是专业的抗原呈递细胞，为固有免疫和适应性免疫反应之间提供了联系。在本研究中，研究了冻干水飞蓟宾提取物对小鼠骨髓来源的树突状细胞（BM-DCs）结构和功能成熟的影响。骨髓细胞在粒细胞-巨噬细胞集落刺激因子和白细胞介素-4（IL-4）的存在下培养，生成的未成熟 DCs用 PN（25、50 和 100μg/mL）或脂多糖（10μg/mL）刺激 48 小时。结果表明，PN 处理以浓度依赖性方式增加了主要组织相容性复合物-II 和各种 DC 成熟标志物（CD40）、激活（CD83）和共刺激（CD86）的表达。与表型标志物的增加一致，功能成熟测定表明，PN 处理 BM-DCs 导致异硫氰酸荧光素-葡聚糖摄取减少，上清液中 IL-12 增加。在转基因 T 细胞激活模型中，PN 处理的 BM-DCs 向 OT-1 小鼠的 Ova 特异性 CD8+T 细胞呈递 Ova 抗原更有效，表现为 T 细胞增殖和 IL-2 产生增加。因此，PN 增强了 BM-DCs 的结构和功能成熟及其抗原呈递功能。这些效应在免疫功能低下的情况下、肿瘤控制和传染病中具有相关性。
