Haemolytic Activities and Adjuvant Effect of Gynostemma Pentaphyllum Saponins on the Immune Responses to Ovalbumin in Mice

In this study, the haemolytic activities of Gynostemma pentaphyllum saponins (GPS) and its adjuvant potential on the immune responses of ICR mice against ovalbumin (OVA) were evaluated. GPS showed a slight haemolytic effect, with its haemolytic activity being 10.20% and 4.90% at concentrations of 500 and 250 microg/mL, respectively. ICR mice were immunized subcutaneously with OVA 100 microg alone or with OVA 100 microg dissolved in saline containing aluminium hydroxide gel (Alum, 200 microg), QuilA (10 and 20 microg) or GPS (50, 100 or 200 microg) on days 1 and 15. Two weeks later (day 28), concanavalin A (Con A)-, lipopolysaccharide (LPS)- and OVA-stimulated splenocyte proliferation and OVA-specific antibodies in serum were measured. GPS significantly enhanced the Con A-, LPS- and OVA-induced splenocyte proliferation in the OVA-immunized mice, especially at a dose of 100 microg (p < 0.05 or p < 0.001). OVA-specific IgG, IgG1 and IgG2b antibody levels in serum were also significantly enhanced by GPS compared with the OVA control group (p < 0.05, p < 0.01 or p < 0.001). In conclusion, the results suggest that GPS could be used safely as an adjuvant with low or no haemolytic effect.