Haemolytic activities and adjuvant effect of Anemone raddeana saponins (ARS) on the immune responses to ovalbumin in mice

In this study, saponins (ARS) extracted from the rhizoma of Anemone raddeana were evaluated for their haemolytic activities and its potential ability as adjuvant on the cellular and humoral immune responses of ICR mice against ovalbumin. The haemolytic activity of ARS was determined using 0.5% rabbit red blood cell. ARS showed a slight haemolytic effect, with its haemolytic percents being 16.50 and 3.56% at the concentrations of 500 and 250 μg/ml, respectively. ICR mice were immunized subcutaneously with OVA 100 μg alone or with OVA 100 μg dissolved in saline containing Alum (200 μg), QuilA (10 and 20 μg) or ARS (50, 100 or 200 μg) 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. ARS significantly enhanced the Con A-, LPS-, and OVA-induced splenocyte proliferation in the OVA-immunized mice especially at a dose of 100 μg (P < 0.01 or P < 0.05). The OVA-specific IgG, IgG1 and IgG2b antibody levels in serum were also significantly enhanced by ARS compared with OVA control group (P < 0.01 or P < 0.05). Moreover, no significant differences (P > 0.05) were observed between enhancing effect of ARS and QuilA on the OVA-specific IgG2b antibody responses to OVA in mice. The results suggest that ARS showed a slight haemolytic effect and enhanced significantly a specific antibody and cellular response against OVA in mice.