Liposome can improve the adjuvanticity of astragalus polysaccharide on the immune response against ovalbumin.

In vitro, the effects of astragalus polysaccharide liposome (APSL) on splenocyte proliferation of mice were determined. The results showed that APSL could significantly promote splenocyte proliferation synergistically with PHA and LPS and the efficacy were superior to those of astragalus polysaccharide (APS) and blank liposome (BL). In immune response experiment, the adjuvant effect of APSL at three doses, APS, BL and aluminum hydroxide (alum) were compared on mice immunized subcutaneously with ovalbumin (OVA). The results showed that APSL could significantly promote splenocyte proliferation, enhance specific IgG, IgG1 and IgG2a antibody responses, promote IFN-γ and IL-6 secretion, and the efficacy were significantly better than alum at most time points. These results indicated that APSL could significantly improve the adjuvanticity and drug action of APS, and its high and medium doses possessed the best efficacy. Therefore, the liposome would be expected to exploit into a new-type preparation of APS.