ABSTRACT
Objective To investigate the effects of water extracts of Lepidium meyenii walp (LMWE) collected from two different places in Xinjiang on the maturation and function of dendritic cells (DCs) and to evaluate their roles in immunoregulation. Methods Water extracts of LMWE growing in Tashikuergan County (Ta xian) and A La gou of Xinjiang were prepared and named as LMWE-T and LMWE-A,respectively. Bone marrow-derived DCs and splenocytes isolated from C57BL/6 mice were treated with different concentrations of polysaccharide extracts from LMWE-T/A. Effects of LMWE-T/A on the per-centage and apoptosis of DC,expression of co-stimulatory molecules and secretion of cytokines were detected by flow cytometry and ELISA. MTT assay was used to analyze the proliferation of splenocytes. Changes in the functions of DC were evaluated by mixed lymphocyte reaction(MLR). Results LMWE-T/A had no in-fluence on the percentage and viability of DC. Expression of CD40 and CD86,and secretion of TNF-α,IL-12p40 and IFN-γ were significantly increased by LMWE-T/A treatment in a dose-dependent manner. LMWE-T/A treatment enhanced the functions of DCs and also dose-dependently promoted the proliferation of splenocytes. LMWE-A was more effective than LMWE-T in promoting CD86 expression,IFN-γ secretion and splenocyte proliferation. Pretreatment with TAK-242,an inhibitor of Toll-like receptor 4(TLR4),could sig-nificantly inhibit the regulatory effects of LMWE-T/A on CD40 expression and the secretion of TNF-α and IL-12p40. Conclusion This study shows that LMWE could promote the maturation of DC through TLR4 signaling pathway,enhance the functions of DC without side effects on DC survival,and increase the prolif-eration of splenocytes,indicating that LMWE has a potential immunopotentiating effect. LMWE-A has better effects than LMWE-T on immune enhancement.
ABSTRACT
Objective To study the changes in morphology , phenotypes and gene expression pro-files of dendritic cells (DCs) following treatment with Seabuckthorn flavones (SF).Methods DCs were treated with 200μg/ml of SF and then cultured for 7 days.Changes in the morphology of DCs were observed under light microscope .Flow cytometry was used to detect DC surface molecules .Total RNA was extracted to construct the library for digital gene expression profiling ( DGE ) .Differentially expressed genes were screened out and further analyzed by gene ontology ( GO) enrichment analysis and Kyoto encyclopedia of genes and genomes ( KEGG ) pathway enrichment analysis .Results Compared with control group , SF treatment significantly enhanced the expression of HLA-DR, CD80, CD83 and CD86 on DCs.A total of 355 differentially expressed genes were screened out by DGE , including 176 up-regulated genes and 179 down-regulated genes .GO enrichment was mainly involved in the regulation and development of the immune sys -tem and other biological processes .KEGG pathway analysis showed that the significantly enriched pathways were closely related to inflammation , the immune system, cancer and other diseases .Conclusion SF can promote the expression of DC co-stimulatory molecules and pro-mature molecules, and regulate the expres-sion of immunity-related genes such as CD11a, SLAMF6, LMCD1, TSC22D3 and IKZF3.