Interferon-gamma is a pleiotropic cytokine characteristically prouduced by natural killer cells and T helper 1 type cells in response to antigenic or mitogenic stimulus. Apart from its capacity to directly exert anti-viral activity and anti-tumor activity, it plays many crtitical roles in the modulation of immune reponses. Due to its important biological activity, IFN- Y now is a focus among the medical and biological fields, and recombinant IFN- Y produced by recombinant technology has been successfully im...