Enhancement of Extracts from Celastrus orbiculatus on Maturation and Function of Dendritic Cells in vitro and in vivo / 中草药·英文版

ABSTRACT

Objective To examine the immunoregulation of Celastrus orbiculatus extracts(COE),a traditional Chinese medicine,on maturation and function of dendritic cells(DCs)in vitro and in vivo.Methods In vitro,after treated with COE indifferent nontoxic concentrations(0,10,20,40,80,and 160 μg/mL)for 5 d,the surface immunological molecules andcytokine secretion of mice bone marrow-derived DCs in response to COE were analyzed by flow cytometric analysis(FACS)and enzyme linked immunosorbent assay(ELISA),respectively.In vivo,mouse hepatoma cells(Hepal-6,1 ×106)were injected sc and were treated with different dosages of COE(10,20 or 40 mg/kg/d).Effects on tumor growth were determined by tumor volume and histology analysis after 28 d administration of COE.The relative proportions ofmature DCs and CD8+ T cells were measured in mononuclear cells that had been isolated from spleen by FACS.Results COE stimulated IL-2 and IFN-γ secretion of DCs,simultaneously enhanced the maturation of DCs byenhancing immunological molecule(CD40,CDS0,CD86,H-2Kb,and I-Ab)expression in a dose-dependent manner.Furthermore,the chcmotactic responses of DCs were significantly higher in COE-treated than untreated DCs,in association with higher chcmokine receptor 7 expression.Furthermore,COE increased DCs produce IFN-γ and IL-2 ina dose-dependent manner when the concentration of COE less than 40 μg/mL,decreased DCs produce IL-10 and IL-4also in a dose-dependent manner.In in vivo studies,COE can not only suppress growth of malignant hepatocellularcarcinomas but also stimulate maturation of DCs,associated with strongly enhanced CD8+ CTL responses.ConclusionThese data provide new insight into the mechanism of action of COE and indicate that the stimulation of maturation andfunction of DCs by COE contributes to its immunoregulatory effects.