Laboratory for Immunopharmacology of Microbial Products, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Horinouchi, Hachioji, Tokyo, Japan.
Immunopharmacol Immunotoxicol. 2012 Aug;34(4):561-70. doi: 10.3109/08923973.2011.633526. Epub 2011 Nov 29.
Agaricus brasiliensis (Agaricus blazei Murrill) is well known as a medicinal mushroom. Fruit body of A. brasiliensis is rich in β-glucan and has shown benefits for various diseases. Both hot and cold water extraction are traditional methods for intake of this mushroom extract. In the present study, we prepared cold water extract of the fruit body of A. brasiliensis (ACWS). The 1,3-β-glucan segment of this fraction was too small and did not interact with the 1,3-β-glucan receptor, dectin-1. However, ACWS could induce production of various cytokines including IL-6 from murine splenocytes. Therefore, we aimed to identify the receptor that modulates IL-6 production using ACWS. We focused our attention on Toll-like receptors (TLRs) and examined them as follows. (i) The interaction between TLRs and ACWS was screened using HEK293 cells transfected with TLR plasmid. (ii) IL-6 production from splenocytes induced by ACWS was inhibited by treatment of anti-TLR antibodies. (iii) Direct binding activity between TLR protein and ACWS was assessed by ELISA-like assay. ACWS was found to activate HEK293 cells via TLR2, 4 and 5. However, only anti-TLR2 monoclonal antibody suppressed IL-6 production from splenocytes. In addition, ACWS has the ability to bind directly to TLR2 protein. Accordingly, we suggest that fruit body of A. brasiliensis has some water-soluble TLR ligand complexes, and TLR2 on splenocytes strongly induces IL-6 production.
巴西蘑菇（Agaricus blazei Murrill）作为一种药用蘑菇广为人知。巴西蘑菇的子实体富含β-葡聚糖，对各种疾病均具有益处。热水提取法和冷水提取法都是摄入该蘑菇提取物的传统方法。在本研究中，我们制备了巴西蘑菇子实体的冷水提取物（ACWS）。该部分的 1,3-β-葡聚糖片段太小，不能与 1,3-β-葡聚糖受体 dectin-1 相互作用。然而，ACWS 可以诱导包括 IL-6 在内的各种细胞因子从鼠脾细胞中产生。因此，我们旨在使用 ACWS 鉴定调节 IL-6 产生的受体。我们将注意力集中在 Toll 样受体（TLRs）上，并进行了如下研究。（i）使用转染 TLR 质粒的 HEK293 细胞筛选 TLR 与 ACWS 的相互作用。（ii）ACWS 诱导的脾细胞中 IL-6 的产生被抗 TLR 抗体的处理所抑制。（iii）通过 ELISA 样测定评估 TLR 蛋白与 ACWS 之间的直接结合活性。ACWS 通过 TLR2、4 和 5 激活 HEK293 细胞。然而，只有抗 TLR2 单克隆抗体抑制了脾细胞中 IL-6 的产生。此外，ACWS 具有与 TLR2 蛋白直接结合的能力。因此，我们认为巴西蘑菇的子实体具有一些水溶性 TLR 配体复合物，并且 TLR2 可强烈诱导脾细胞中 IL-6 的产生。
