RESUMO
Human stem cell is a unique cell population with the ability of self renewal and differentiation. There are many types of stem cells in human embryonic body and adult tissues, and they have crucial functions in human development. The stem cell differentiation is of great importance for the success of stem cell based therapies,whose effectiveness is determined by the intrinsic property of the cells and the cell microenvironment. The studies on the differentiation of human stem cell include the structural property of the cell and the molecular mechanism in vivo and in vitro . The aim of scientists is to gain the renewable and directional differential stem cells in vitro and use them for a variety of human diseases.
RESUMO
Interferon-gamma(IFN-?)was induced by PWM or esculentoside in human splenic lymphocytes. PWM-induced IFN-r was partially purified to a spe. act. of 106 RU/mg protein by batch adsorption on controlled-pore glass (CPG) beads and desorption by ethylene glycol in PBS.Use of native-made micro-pore glass(MPG)instead of CPG to purify IFN-r showed similar purification efficacy.Both CPG and MPG recovered could be regenerated for repeated use.The yield from glass beads was further purified to a spe.act.of 107 RU/mg protein, with about 78%recovery, by the anti-new-born calf serum antibodies-Sepharose 4B(ACS)column chromatography.Almost all the antiviral activity induced by PWM or esculentoside was destroyed by pH 2 or heat at 56℃ and neutralized by monoclonal antibody against HuIFN-r, thereby identified as HuIFN-r. Bio-Gel P-200 chromatography resulted in two peaks of activity for PWM-induced IFN, a major one with molecular weight of 40,000-45,700 and a minor one of 25,700 dalton, but only one peak with molecular weight of 45,700-49,000 for esculentoside-induced IFN.