Immunomodulatory activity of the seeds of Plantago asiatica L.

Ethnopharmacological relevanceThe seeds of Plantago asiatica L. were often used as a traditional Chinese medicine for some immunologically weak patients suffering from chronic illness. These uses could be related to immunomodulatory properties of the plant.Aim of the studyIn this study, effects of extract of the seeds of Plantago asiatica L. (ES-PL) were investigated on the maturation of dendritic cells (DCs), which play significant role in primary immune system.Materials and methodsThe phenotypes of DCs were analyzed by using flow cytometry while phagocytosis was assessed by the uptake of FITC-dextran. Antigen presenting ability to allogeneically naïve or syngeneically primed T lymphocytes was examined by the lymphocyte proliferation of mixed lymphocyte reaction (MLR). In addition, the level of chemokine receptor CCR7 mRNA was determined by RT-PCR.ResultsDCs treated with ES-PL expressed higher levels of MHC class II molecules and major costimulatory molecules such as CD80 and CD86. Functional maturation of DCs treated with ES-PL was confirmed by decreased mannose receptor-mediated endocytosis and increased antigen presenting abilities to allogeneically naïve or syngeneically primed T lymphocytes. The CCR7 mRNA expression in DCs treated with ES-PL was also enhanced.ConclusionsThese results indicated that ES-PL could induce the maturation of murine DCs.