Polysaccharide Isolated from Zizyphus jujuba (紅棗 Hóng Zǎo) Inhibits Interleukin-2 Production in Jurkat T Cells

Zizyphus jujuba (紅棗 Hóng Zǎo), a traditional Chinese herb widely used in many Asian countries, has been shown to possess vital biological activities such as anti-cancer activity. The objective of this study was to evaluate the immunomodulatory effect of deproteinated polysaccharide (DP) isolated from Z. jujuba. The DP isolated from Z. jujuba consisted of two polysaccharide fractions and their molecular weights (MWs) were found to be 143,108 and 67,633 Da, respectively. The DP could significantly decrease interleukin (IL)-2 production in phytohemagglutinin (PHA)-activated Jurkat T cells in a dose-dependent manner after 48 h of incubation, with the inhibition being 47.5%, 61.2%, and 81.7% for DP concentrations of 0.75, 1.75, and 2.5 mg/ml, respectively. Thus, our study showed that DP isolated from Z. jujuba may possess anti-inflammatory activity as it could significantly reduce IL-2 production in activated Jurkat T cells.