Effect of selenylation modification on immune-enhancing activity of Atractylodes macrocephala polysaccharide

The Atractylodes macrocephala polysaccharide (AMP) was extracted purified and modified in selenylation by Nitric acid-sodium selenite method to get nine selenizing AMPs (sAMPs), sAMP(1)-sAMP(9). In vitro test their effects on chicken peripheral lymphocyte proliferation were determined by MTT assay. The results showed that nine sAMPs and AMP at five concentrations could significantly promote lymphocyte proliferation, the actions in six sAMPs were significantly stronger than that in AMP, and in sAMP(9) was the strongest. In vivo test, 14-day-old chickens vaccinated with ND vaccine were injected respectively with sAMP(9) and AMP, the peripheral lymphocytes proliferation, serum antibody titer, IFN-γ, IL-2 and IL-6 contents were determined. The results displayed that the sAMP could significantly promote lymphocyte proliferation and elevate the antibody titers and content of IFN-γ, IL-2 and IL-6 in comparison with unmodified AMP. These results indicate that selenylation modification can significantly enhance the immune-enhancing activity of AMP.