Astragaloside II triggers T cell activation through regulation of CD45 protein tyrosine phosphatase activity
Astragaloside II triggers T cell activation through regulation of CD45 protein tyrosine phosphatase activity
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黄芪甲苷 II 通过调节 CD45 蛋白酪氨酸磷酸酶活性触发 T 细胞激活
DOI：
10.1038/aps.2012.208
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发表时间：
2013-04-01
影响因子：
8.2
通讯作者：
Zuo, Jian-ping
中科院分区：
文献类型：
--
作者：
Wan, Chun-ping;Gao, Li-xin;Zuo, Jian-ping
目的：研究阿斯塔拉加糖苷的免疫调节活性，来自传统的滋补草药阿斯塔拉加素膜的活性化合物，并探索动作作用的分子机制，重点是CD45蛋白质酪氨酸酪氨酸磷酸酶（CD45 PTPase）（CD45 PTPase），在t lympphysty and te lympphysty中起着关键的作用。由小鼠制备。使用比色测定法评估CD45 PTPase活性。使用[H-3] - 胸苷掺入测定法测量细胞增殖。分别使用ELISA和RT-PCR检查了细胞因子蛋白和mRNA。使用流式细胞术分析了包括CD25和CD69在内的激活标记。使用Western印迹分析检测到LCK（Tyr505）的激活。向小鼠注射免疫抑制剂环磷酰胺（CTX，80 mg/kg），并给予阿斯塔拉加属II（50 mg/kg）。消除：results：Astagaloside I，II，III，III和IV浓度与PNPP/OMFP水解的CD45介导的10.33浓度增加了3.33的浓度g/ml。星形前II（10和30 nmol/L）显着增强了由CONA，同种抗原或抗CD3诱导的原发性脾细胞的增殖。星形前II（30 nmol/L）显着增加了IL-2和IFN-gamma分泌，在原代脾细胞中上调了IFN-gamma和T-bet的mRNA水平，并在TCR刺激后促进了原代CD4（+）T细胞上的CD25和CD69表达。此外，阿斯拉胶II（100 nmol/L）促进了原代T细胞中LCK（Tyr505）的CD45介导的去磷酸化，这可以被特定的CD45 PTPase抑制剂阻止。在CTX诱导的免疫抑制小鼠中，口服星形镜II恢复了脾脏T细胞的增殖以及IFN-GAMMA和IL-2的产生。然而，星际胶质苷II对B细胞的增殖没有明显的影响。结论：黄色属II通过调节CD45 PTPase的活性来增强T细胞的激活，这可以解释为什么在治疗免疫抑制疾病方面用作静脉草药BGE。
Aim:To investigate the immunomodulating activity of astragalosides, the active compounds from a traditional tonic herb Astragalus membranaceus Bge, and to explore the molecular mechanisms underlying the actions, focusing on CD45 protein tyrosine phosphatase (CD45 PTPase), which plays a critical role in T lymphocyte activation.Methods:Primary splenocytes and T cells were prepared from mice. CD45 PTPase activity was assessed using a colorimetric assay. Cell proliferation was measured using a [3 H]-thymidine incorporation assay. Cytokine proteins and mRNAs were examined with ELISA and RT-PCR, respectively. Activation markers, including CD25 and CD69, were analyzed using flow cytometry. Activation of LCK (Tyr505) was detected using Western blot analysis. Mice were injected with the immunosuppressant cyclophosphamide (CTX, 80 mg/kg), and administered astragaloside II (50 mg/kg).Results:Astragaloside I, II, III, and IV concentration-dependently increased the CD45-mediated of pNPP/OMFP hydrolysis with the EC 50 values ranged from 3.33 to 10.42 μg/mL. Astragaloside II (10 and 30 nmol/L) significantly enhanced the proliferation of primary splenocytes induced by ConA, alloantigen or anti-CD3. Astragaloside II (30 nmol/L) significantly increased IL-2 and IFN-γ secretion, upregulated the mRNA levels of IFN-γ and T-bet in primary splenocytes, and promoted CD25 and CD69 expression on primary CD4+ T cells upon TCR stimulation. Furthermore, astragaloside II (100 nmol/L) promoted CD45-mediated dephosphorylation of LCK (Tyr505) in primary T cells, which could be blocked by a specific CD45 PTPase inhibitor. In CTX-induced immunosuppressed mice, oral administration of astragaloside II restored the proliferation of splenic T cells and the production of IFN-γ and IL-2. However, astragaloside II had no apparent effects on B cell proliferation.Conclusion:Astragaloside II enhances T cell activation by regulating the activity of CD45 PTPase, which may explain why Astragalus membranaceus Bge is used as a tonic herb in treating immunosuppressive diseases.