Preliminary characterization and immunostimulatory activity of polysaccharides from Glossaulax didyma

In the present study, we investigated the preliminary characterization, both in vitro and in vivo immunostimulatory activity of polysaccharides from Glossaulax didyma (GPS). The results of chemical and gas chromatography analysis indicated that GPS was mainly composed of glucose with high contents of uronic acid and sulfate. For immunostimulatory activity in vitro, GPS could stimulate the proliferation of splenocytes and enhance neutral red phagocytosis, TNF-α production level and acid phosphatase activity in mouse peritoneal macrophages. For immunostimulatory activity in vivo, the administration of GPS could significantly increase the level of serum hemolysin in cyclophosphamide-treated mice. The results provided evidences that GPS possessed significant immunostimulatory activity and might be one of important active substances responsible for the immunostimulatory effect of G. didyma.