Astragalus polysaccharides(APS) induces the cord blood monocytes into mature dendritic cells(DCs) directly and its impact on T cells proliferation / 中国免疫学杂志

ABSTRACT

Objective:To observe the effect of Astragalus polysaccharides(APS) on inducing the cord blood monocytes into mature dendritic cells(DCs) in vitro and to investigate their morphous,cellar immunological characteristics,and contribution to T cell proliferation.Methods:①The cord blood monocytes were isolated by lymphocyte isolating solution under axenic condition,and three groups were divided.②Cells cultured with APS in concentration of 100 mg/L as the experiment group, that with the cytokines of GM-CSF/IL-4/TNF-? as the positive control, and another without either GM-CSF/IL-4/TNF-? or APS as the negative control, respectively. The morphology of DCs was identified by inverted optical microscope or scanning electron microscope. The phenotype of 12 days cultures of DCs(CD1a, CD80, CD86 and CD83) were identified by flowcytometry. The DCs preparations from the experiment group were treated with mitomycin for 45 min to remove their proliferative activity as incentive cells in the mixed cultures with allogenic peripheral blood mononuclear cells from healthy volunteers as responders. T cell proliferation induced with the DCs preparations was detected by MTT chromatometry.Results:After cultured for 72 hours, the cell of both the experiment group and the positive control grew dusteringly and began to change from round to irregularin shapes. The longer the cells were cultured, the more obvious the dendritic structure is. The cells of experiment group and the positive control group when cultured for 12 days had the most typical dendritic structure. The negative control group cells had no dendritic structure and became macrophages when cultured for 12 days. The experiment group cells cultured for 10 days showed typical dendritic morphology by SEM. The experiment group cells and the positive group cells cultured for 12 days significantly expressed high level of the phenotypes of DCs(CD1a, CD80, CD86 and CD83) by flowcytometry.And the difference exhibitied statistical significance when compared with the negative control group(P0.05).The mixed lymphocyte reaction showed that the DCs induced by APS trigerred proliferation of allogenic T cells obviously.Conclusion:Both APS and cytokine could induce the cord blood monocytes to differentiate into functional DCs committedly. DCs reduced by APS stimualate proliferation of the allogenic T cells obviously.