文献类型：期刊文献

英文题名：Structural characteristics, immune-activating mechanisms in vitro, and immunomodulatory effects in vivo of the exopolysaccharide EPS53 from Streptococcus thermophilus XJ53

作者：Yue, Yun[1];Han, Jin[2];Shen, Xinyan[1];Zhu, Fei[1];Liu, Yikang[1];Zhang, Wenqing[1];Xia, Wei[1,4];Wu, Mengqi[1,3,4]

机构：[1]East China Univ Sci & Technol, Sch Chem & Mol Engn, Shanghai Key Lab Funct Mat Chem, Shanghai 200237, Peoples R China;[2]Bright Dairy & Food Co Ltd, Dairy Res Inst, State Key Lab Dairy Biotechnol, Shanghai Engn Res Ctr Dairy Biotechnol, Shanghai 200436, Peoples R China;[3]East China Univ Sci & Technol, Sch Pharm, Shanghai Key Lab Chem Biol, Shanghai 200237, Peoples R China;[4]130 Meilong Rd, Shanghai 200237, Peoples R China

年份：2024

卷号：340

外文期刊名：CARBOHYDRATE POLYMERS

收录：;EI(收录号：20242216183325);WOS:【SCI-EXPANDED(收录号:WOS:001248194200001)】；

基金：This study was supported by The 14th five-year National Key Research and Development Plan (2022YFD2100704) of China and Municipal State-owned Assets Supervision and Administration Commission enterprise innovation development and energy upgrading project (2022013) , Shanghai, China.

语种：英文

外文关键词：Streptococcus thermophilus; Exopolysaccharide; Structural characteristics; Immunomodulation mechanism; Zebrafish larvae model

摘要：Our previous investigations have successfully identified the repeating structural units of EPS53, an exopolysaccharide derived from Streptococcus thermophilus XJ53 fermented milk, and substantiated its potential immunomodulatory properties. The present study further elucidated the structural characteristics of EPS53 and investigated the underlying mechanisms governing its in vitro immunoreactivity as well as its in vivo immunoreactivity. The results obtained from multi -detector high performance gel filtration chromatography revealed that EPS53 adopted a rigid rod conformation in aqueous solution, with the weight -average molecular weight of 1464 kDa, the number -average molecular weight of 694 kDa, and the polydispersity index of 2.11. Congo red experiment confirmed the absence of a triple helix conformation. Scanning electron microscopy showed that EPS53 displayed a three-dimensional fibrous structure covered with flakes. The in vitro findings indicated that EPS53 enhanced phagocytosis ability, reactive oxygen species (ROS) production, and cytokine levels of macrophages via the TLR4-mediated NF- kappa B/MAPK signaling pathways as confirmed by immunofluorescence staining experiments, inhibition blocking experiments, and Western blot assay. Additionally, the in vivo experiments demonstrated that EPS53 significantly increased macrophage and neutrophil number while enhancing NO and ROS levels in zebrafish larvae; thus, providing further evidence for the immunomodulatory efficacy of EPS53.