Astragalus polysaccharides effects on immune activity of dentritic cells induced by calcium ionophore

Abstract

Objective To investigate the effect of astragalus polysaccharides on the immune activity of dendritic cells (DC) induced by calcium ionophore A23187. Methods On 20th September 2014, 10-20 mL whole blood were collected from 9 healthy male volunteers through cubital vein under aseptic condition, respectively. Volunteers inclusion criteria: no fever, no infection, and no history of exposure to hepatitis, tuberculosis and other infectious diseases. Using Ficoll density gradient centrifugation to obtain peripheral blood mononuclear cells (PBMC), and selected PBMC in good growth conditions (concentration is 1.0×106/mL) to culture in the flat culture plate of 24 holes with 1 mL per hole. Nine holes of these culture plate were divided into 3 groups by the simple random method, and each group was added different inducing agent as follow: A23187+ astragalus polysaccharides group (n=3): added A23187 and astragalus polyose; sequentially; A23187 group (n=3): added A23187 only; control group (n=3): did not add any inducing agent. Cells of these 3 groups are all cultivated in 37 ℃, 5% CO2 and saturated humidity incubator for 48 h, and then compared the changes of cytomorphology, expressions of immunophenotype and ability of stimulating proliferation of allogeneic T lymphocytes, respectively. Results After cultured for 48 h, the changes of morphological, expressions of immunophenotype and ability to stimulating proliferation of allogeneic T lymphocytes were enhanced of PBMC in A23187+ astragalus polysaccharides group compared to those of A23187 group and control group. After cultured for 48 h, some of the PMBC appeared dendritic processes in A23187 group, and vast majority of PBMC showed obvious dendritic processes in A23187+ astragalus polysaccharides group.The positive rate of CD83, CD80 and CD86 expressing on DC in A23187+ astragalus polysaccharides group increased significantly compared to those of A23187 group[(43.6±8.2)% vs (28.9±6.2)%, t=-25.50, P<0.05; (69.9±19.7)% vs (42.1±5.6)%, t=-82.36, P<0.05 and (79.4±22.5)% vs (49.1±7.8)%, t=-45.21, P<0.05], and control group (t=-65.23, -144.86, -81.28; P<0.05). In different stimulate cell(SC)∶effector cell (EC) ratio of 1∶1 280, 1∶320, 1∶80, 1∶20 and 1∶5, the stimulation index(SI) in A23187+ astragalus polysaccharides group were 1.38±0.39, 3.91±0.94, 7.91±1.48, 10.38±2.46, 11.7±2.83, which were significantly enhanced compared with those of A223187 group (t=-32.45, -65.96, -45.32, -37.89, -64.25; P<0.05), and control group (t=-5.66, -13.08, -29.92, -10.99, -10.51; P<0.05). Conclusions The induction of PBMC induced into DC by A23187 can be enhanced by astragalus polysaccharides, which suggest that astragalus polysaccharides might be involved in the process of PBMC differentiated into DC induced by A23187. Immunomodulatory function of astragalus may play an important role by astragalus polysaccharide. Key words: Dendritic cells; Astragalus polysaccharides; Calcium ionophore; Drugs, Chinese herbal