The JNK/NFκB pathway is required to activate murine lymphocytes induced by a sulfated polysaccharide from Ecklonia cava

• Published in: Biochimica et biophysica acta. General subjects Vol. 1830; no. 3; pp. 2820 - 2829
• Main Authors: Ahn, Ginnae, Bing, So Jin, Kang, Sung-Myung, Lee, Won-Woo, Lee, Seung-Hong, Matsuda, Hiroshi, Tanaka, Akane, Cho, Ik-Hyun, Jeon, You-Jin, Jee, Youngheun
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.03.2013
• Subjects: cytotoxicity; DNA; Ecklonia; Ecklonia cava (E. cava); enzyme-linked immunosorbent assay; flow cytometry; gel electrophoresis; immune response; interleukin-2; JNK; lymphocyte proliferation; Lymphocytes; mice; mitogen-activated protein kinase; NFκB p65; phosphorylation; polymerase chain reaction; polysaccharides; serine proteinases; spleen; Sulfated polysaccharide (SP); T-lymphocytes; transcription factor NF-kappa B; Western blotting; rtPCR; TPCK; DMSO; JNK; PDTC; HRP; FITC; Lymphocytes; EMSA; FBS; Sulfated polysaccharide (SP); SPSS; Ecklonia cava (E. cava); SP; MAPKs; IL; SDS; NFκB; PMA; Con A; CFSE; SDS–PAGE; mAb; PE; E. cava; NFκB p65; ERK; ELISA
• ISSN: 0304-4165; 1872-8006
• DOI: 10.1016/j.bbagen.2012.12.008

The proven immunomodulatory and immune system activating properties of Ecklonia cava (E. cava) have been attributed to its plentiful polysaccharide content. Therefore, we investigated whether the sulfated polysaccharide (SP) of E. cava specifically activates the protein kinases (MAPKs) and nuclear factor-κB (NFκB) to incite immune responses. To assess immune responsiveness, lymphocytes were isolated from spleens of ICR mice and cultured with SP and its inhibitors. Assays included 3H-thymidine incorporation, flow cytometry, real time polymerase chain reaction (rtPCR), enzyme linked immunosorbent assay (ELISA), intracellular cytokine assay, Western blot, and electrophoretic mobility shift assay (EMSA). SP dose-dependently increased the proliferation of lymphocytes without cytotoxicity. In particular, SP markedly enhanced the proliferation and differentiation of CD3+ mature T cells and CD45R/B220+ pan B cells. Additionally, SP increased the expression and/or production of IL-2, IgG1a, and IgG2b compared to that in untreated cells. The subsequent application of JNK (SP600125), NFκB (PDTC), and serine protease (TPCK) inhibitors significantly inhibited the proliferation and IL-2 production of SP-treated lymphocytes as well as the phosphorylation of JNK and IκB, the activation of nuclear NFκB p65, and binding of NFκB p65 DNA. Moreover, co-application of both JNK and NFκB inhibitors completely blocked the proliferation of lymphocytes even in the presence of SP. These results suggest that SP induced T and B cell responses via both JNK and NFκB pathways. The effect of SP on splenic lymphocyte activation was assayed here for the first time and indicated the underlying functional mechanism. ► SP enhances the numerical and functional responses in lymphocytes. ► JNK/NFκB signal pathway is required for SP-induced lymphocyte activation. ► Immunological functions of SP in lymphocytes were evaluated for the first time.