Pingli Li, Haining Tan, Dongqing Xu, Fengxin Yin, Yanna Cheng, Xinke Zhang,Yuhong Liu, Fengshan Wang

Carbohydrate Polymers 110 (2014) 446–455

ABSTRACT

In this study, the effect and mechanisms of curdlan sulfate (CS3) on hepatitis B virus (HBV) infectionand promoting immune response of the mice immunized with recombinant hepatitis B surface protein(HBsAg) were investigated. The results showed that CS3 could inhibit HBV infection of HepG2 and HepaRGcells, especially the process of HBV particle binding to the cell surfaces. The surface plasmon response(SPR) technology indicated that CS3 could bind with recombinant HBsAg and the binding ability dependedon the content of sulfate groups on the polysaccharide chains. Co-administration of CS3 to BALB/c miceimmunized with HBsAg significantly enhanced the influx of macrophages and dendritic cells in spleen,increased antigen-specific CD4⁺and CD8⁺cell numbers, and promoted splenocyte proliferation. Thetiter of HBsAg-specific antibodies was also augmented by use of CS3 as a vaccine adjuvant. The higherexpression of interferon (IFN)-_γ, lower expression of interleukin (IL)-4, and higher IgG2a/IgG1 ratio withinthe anti-HBsAg antibodies in mice immunized with HBsAg plus CS3 than those in mice receiving HBsAgalone indicated that CS3 induced a shift toward a Th1-biased immune response. These results presentedthat CS3 could be developed as an immunotherapy agent or vaccine adjuvant for HBV infection treatmentor prevention.