Signaling pathway underlying splenocytes activation by polysaccharides from Atractylodis macrocephalae Koidz

• Published in: Molecular immunology 2019-07, Vol.111, p.19-26
• Main Authors: Xu, Wei, Fang, Sijia, Cui, Xuemei, Guan, Ran, Wang, Yong, Shi, Fushan, Hu, Songhua
• Format: Article
• Language: English
• Subjects: Atractylodis macrocephalae Koidz; Immunomodulaton; Lymphocytes; Polysaccharides; Signaling pathway
• ISSN: 0161-5890; 1872-9142
• DOI: 10.1016/j.molimm.2019.03.004

•RAMPtp activated splenocytes via MAPKs and NF-κB signaling pathways.•RAMPtp stimulated splenocytes by targeting NFAT, NF-κB and AP-1 transcription factors.•TLR4 might not be involved in RAMPtp-mediated splenocytes activation.•Multiple cytokine families were detected in RAMPtp-mediated splenocytes activation. Previous study demonstrated that total polysaccharides isolated from Atractylodis macrocephalae Koidz. (RAMPtp) were effective to eliminate intramammary infection in cows. The present study was designed to investigate the immunomodulatory activity of RAMPtp in mouse splenocytes. Splenocyte proliferation, natural killer (NK) cytotoxicity, productions of NO and cytokines, transcription factor activity as well as the signal pathways and receptor were examined. The results showed that RAMPtp significantly promoted splenocyte proliferation and made the cells enter S and G2/M phases, increased ratios of T/B cells, boosted NK cytotoxicity, enhanced transcriptional activities of nuclear factor of activated T cells (NFAT), nuclear factor κB (NF-κB) and activator protein 1 (AP-1), and stimulated secretions of NO, immunoglobulin G (IgG) and multiple cytokine families (IL-1α, IL-1β, IL-2, IL-3, IL-4, IL-6, IL-10, IL-12p40, IL-12p70, IL-13, IFN-γ, TNF-α, G-CSF, GM-CSF, KC, MIP-1α, MIP-1β, RANTES and Eotaxin). In addition, all the specific inhibitors against the mitogen-activated protein kinases (MAPKs) and NF-κB significantly suppressed the IL-6 production induced by RAMPtp. Moreover, splenocytes from Toll-like receptor 4 (TLR4) deficient mouse responded equally to RAMPtp stimulation as the wild-type. Therefore, RAMPtp might induce splenocytes activation at least in part via the TLR4-independent MAPKs and NF-κB signaling pathways. The present results would be useful to further understand the immunomodulatory mechanisms of RAMPtp in elimination of intramammary infection in cows.