The Effect of Shallot (Allium Hirtifolium) Extract on Profile of Th1/Th2 Cytokines in Balb/C Mouse Splenic Lymphocytes

Modulation of cytokine secretion by phytoconstituents offers a novel approach for treatment of diseases. A class of herbal medicines, known as immunomodulators, alters the activity of immune system through the dynamic regulation of cytokines secretion. Cytokines modulate functions of immune cells, including Th1 (T helper 1) or Th2 responses, responsible for cellmediated and humoral immunity, respectively. Here, we evaluated the immunomodulatory effects of hydroalcoholic extract of shallot (A. hirtifolium) on immune response in BALB/c mouse. Extract of shallot bulbs were prepared and two doses of extract (80 and 400 mg/kg) were injected intraperitoneally within 10 days. Thereafter, splenic mononuclear cells (SMNC) were isolated and secreted IFN-γ (Interferon-gamma), Il-4 (Interleukin-4) as two prototypes of Th1/Th2 cytokines, and TNF-α (Tumor Necrosis Factor-alpha) levels were assayed using Enzyme-linked Immunosorbent assay (ELISA) kits. The results showed that shallot extract significantly reduced Th2 and Th1 responses by down-regulation of Il-4 and IFN-γ levels. The extract also reduced TNF-α, the major proinflammatory cytokine. These data indicated the suppressive potential of shallot extract on the signature cytokines of Th1/Th2 subsets and TNF-α.