Abstract: To study the effect of Urtica macrorrhiza Hand-Mazz polysaccharides on in vitro induction of cord blood monocyte into dendritic cells(DCs) as well as its effect on the maturation and differentiation of DCs.Cord blood mononuclear cytes were separated by centrifuge in density gradient and were divided into three groups:cells cultured with U.macrorrhiza polysaccharides(200 mg/L) as experimental group,cells cultured with the cytokines of IL-4, GM-CSF and TNF-α as positive control group and cells cultured without either IL-4, GM-CSF,TNF-α or U.macrorrhiza polysaccharides as negative control group.The phenotype of 10 days cultures of DCs(CD1a,CD80,CD83,CD86 and HLA-DR) were identified by flow cytometry.The results showed that compared with negative control group,cells of experimental group and positive group cultured for 10 days expressed significant increasing of the phenotypes of CD80,CD83,CD86,HLADR and CD1a by flow cytometry.Hence,it was concluded that U.macrorrhiza polysaccharides may induce the cord blood monocytes into mature DCs.

Key words: dendritic cells, Urtica macrorrhiza Hand-Mazz polysaccharide, cord blood monocytes, cytokin