Department of Veterinary Medicine, College of Animal Sciences, Zhejiang University, Hang Zhou, 310058, PR China.
Beijing Key Laboratory of Traditional Chinese Veterinary Medicine, Beijing University of Agriculture, Beijing, 102206, PR China.
Carbohydr Polym. 2020 Apr 15;234:115906. doi: 10.1016/j.carbpol.2020.115906. Epub 2020 Jan 25.
The present study was to investigate the molecular mechanism underlying lymphocyte activation by total polysaccharides from Atractylodis macrocephalae (RAMPtp). The results showed that RAMPtp significantly promoted the secretions of cytokines (IFN-γ, IL-1α, IL-21, IFN-α, CCL4, CXCL9 and CXCL10), increased the proportions of CD4 and CD8 subpopulations, and enhanced the expressions of c-JUN, NFAT4, STAT1 and STAT3. microRNA sequencing identified 67 differentially expressed miRNAs (DEMs) in RAMPtp-stimulated SMLN lymphocytes, including 55 up-regulated and 12 down-regulated. GO and KEGG enrichment analyses of the predicted DEMs-targeted genes indicated that they were associated with immune system pathways, including PI3K-Akt, MAPKs, Jak-STAT and Calcium signaling pathways, which were confirmed by western blot and pathway inhibition assays. RAMPtp was further observed to favor immunostimulatory effect on both T and B lymphocytes via binding to TCR and membrane Ig individually. These findings might explain the immunomodulatory mechanism of RAMPtp in ameliorating the bovine intramammary infection.
本研究旨在探讨白术总多糖（RAMPtp）激活淋巴细胞的分子机制。结果表明，RAMPtp 能显著促进细胞因子（IFN-γ、IL-1α、IL-21、IFN-α、CCL4、CXCL9 和 CXCL10）的分泌，增加 CD4 和 CD8 亚群的比例，并增强 c-JUN、NFAT4、STAT1 和 STAT3 的表达。microRNA 测序鉴定了 RAMPtp 刺激的 SMLN 淋巴细胞中 67 个差异表达的 miRNA（DEMs），包括 55 个上调和 12 个下调。预测的 DEMs-靶向基因的 GO 和 KEGG 富集分析表明，它们与免疫系统途径相关，包括 PI3K-Akt、MAPKs、Jak-STAT 和钙信号通路，这通过 Western blot 和通路抑制实验得到了证实。RAMPtp 还通过分别与 TCR 和膜 Ig 结合，有利于 T 和 B 淋巴细胞的免疫刺激作用。这些发现可能解释了 RAMPtp 在改善牛乳腺炎中的免疫调节机制。
