Jin M, Kim S, Kim B K
College of Pharmacy, Seoul National University, Korea.
Int J Immunopharmacol. 1996 Aug-Sep;18(8-9):439-48. doi: 10.1016/s0192-0561(96)00018-5.
Many immune modulating compounds have been isolated from fungal extracts, but the molecular mechanisms of their action have rarely been elucidated. In this study we isolated a proteoglycan from cultured mycelia of Lentinus lepideus and tested its effects on murine spleen cells. The acidic-polysaccharide fraction was obtained by extraction with hot water followed by purification using DEAE-cellulose anion exchange. The molecular mass of the compound was determined by Sepharose CL-4B gel filtration to be approximately 47 kDa. When cultured in the presence of the compound, spleen cells from C3H mice underwent rapid cell proliferation and cell aggregation. Treatment with the compound also caused a 10-fold increase in [3H]-thymidine incorporation compared to a control, confirming cell proliferation. Flow cytometry analysis indicated that the affected cell population was mainly B cells. As one approach to understanding the molecular mechanism of this action, we investigated the effects of the compound on cellular transcription factors which are known to control the proliferation of immune cells. Using gel retardation assays, we found that the compound significantly activated NF-kappa B but not AP-1 in spleen cells. Taken together, the data suggest that the proteoglycan compound is a biological response modifier that stimulates B cell proliferation, probably by regulating cellular transcription factors such as NF-kappa B.
许多免疫调节化合物已从真菌提取物中分离出来，但其作用的分子机制却鲜有阐明。在本研究中，我们从香菇培养菌丝体中分离出一种蛋白聚糖，并测试了其对小鼠脾细胞的影响。通过热水提取，然后用DEAE - 纤维素阴离子交换进行纯化，得到酸性多糖部分。通过Sepharose CL - 4B凝胶过滤测定该化合物的分子量约为47 kDa。当在该化合物存在下培养时，C3H小鼠的脾细胞经历了快速的细胞增殖和细胞聚集。与对照组相比，用该化合物处理还使[3H] - 胸腺嘧啶核苷掺入增加了10倍，证实了细胞增殖。流式细胞术分析表明，受影响的细胞群体主要是B细胞。作为理解这种作用分子机制的一种方法，我们研究了该化合物对已知控制免疫细胞增殖的细胞转录因子的影响。使用凝胶阻滞试验，我们发现该化合物在脾细胞中显著激活了NF - κB，但未激活AP - 1。综上所述，数据表明该蛋白聚糖化合物是一种生物反应调节剂，可能通过调节诸如NF - κB等细胞转录因子来刺激B细胞增殖。
