AIP1, a carbohydrate fraction from Artemisia iwayomogi, modulates the functional differentiation of bone marrow-derived dendritic cells.

Dendritic cells (DCs) are the most potent antigen-presenting cells (APC) particularly important in the initiation of primary T cell-mediated immune responses. Thus, inhibition of the differentiation and function of DC could lead to the suppression of immunological hyperresponsiveness. Artemisia iwayomogi, a member of the Compositae, is a perennial herb easily found in Korea and has been used as a traditional anti-inflammatory medicine. We investigated suppressive effects of carbohydrate fraction 1 from the water extracts of A. iwayomogi (AIP1) on the differentiation and function of bone marrow-derived dendritic cells. Bone marrow cells were cultured in the presence of granulocyte monocyte-colony stimulating factor (GM-CSF) and interleukin (IL)-4 for 6-7 days. Then, non-adherent cells were harvested for subsequent analyses. Percentage(s) of CD11c+ MHC II+ cell population(s) mostly composed of immature or mature DC and the allogeneic T cell stimulating ability of the cells were reduced by AIP1. Proteomic analyses along with RT-PCR revealed that expressions of several proteins including TNF receptor-associated factor (TRAF) 5-like protein, pyruvate kinase M2 (PKM2), and coactosin-like protein 1 (CLP1) were down-regulated upon AIP1 treatment.