A proprietary extract from North American ginseng (Panax quinquefolium) enhances IL-2 and IFN-γ productions in murine spleen cells induced by Con-A☆

Abstract A patented aqueous extract from North American ginseng ( Panax quinquefolium ), containing mainly oligosaccharides and polysaccharides, is commercially available over the counter as COLD-FX (CVT-E002). This proprietary extract is used for the treatment of upper respiratory tract infections. Its in vitro stimulating effects on the immunoglobulin production by B lymphocytes and on natural immune responses by peritoneal exudates macrophages have been previously reported. Using C57 BL/6 mice, an ex vivo study was conducted to examine Con-A-induced splenocytic productions of interleukin-2 (IL-2) and interferon-gamma (IFN-γ) as markers of acquired immune responses. CVT-E002 (10–500 μg/ml) significantly increased Con-A-induced IL-2 and IFN-γ productions in spleen cells in a dose-dependent manner. Such response was seen by the ginseng extract originated from three different lots, suggesting consistency between the lots.