Objective:To study the in-vitro inhibitory of limax polysaccharide on hepatitis B virus. Methods:The cell toxicity of limax polysaccharide was determined with MTT method

and the effect of limax polysaccharide on HBsAg and HBeAg secreted by HepG2.2.15 cells was evaluated with ELISA method on the ninth day of incubation. real-time PCR was used for determining secrected HBV-DNA in the culture medium. Results:limax polysaccharide had no obvious cell toxicity at the concentration less than 1 mg·mL-1 and depressed duplication on HBV-DNA. Limax polysaccharide had obvious restrain effect on HBsAg and HBeAg with maximum inhibition ratio addig up to 56.2%and 58.1%. The therapeutic index of limax polysaccharide was 19.98% for HBsAg and 22.78% for HBeAg. There was certain inhibition on replication of HBV-DNA(P<0.05). Conclusion:Limax polysaccharid has no obvious immediate cell toxicity on the HepG 2.2.15 cell and can inhibit duplication of hepatitis B virus in vitro.