In Vitro augmentation of natural killer activity and interferon-γ production in murine spleen cells with Agaricus blazei fruiting body fractions

Abstract

Aqueous extracts of the Agaricus blazei fruiting body prepared at different temperatures were fractionated by ethanol precipitation with various ethanol concentrations. The original aqueous extracts of A. blazei failed to stimulate natural killer (NK) cell activity in murine spleen cells in vitro, but the strongest effect was observed in a 30% ethanol-soluble-50% ethanol-insoluble fraction prepared from the extract at 40°C (fraction A-50). Fraction A-50 also showed the strongest augmenting effect on interferon (IFN)-γ production. This augmentation of NK activity and IFN-γ production by fraction A-50 was completely abrogated by a heat treatment.