Study On Mechanism Of Zwitterionic Polysaccharide In Immune Response And Immunomodulatory

As polysaccharide is a T cell indepentant antigen which resists the pathogens such as the beacteria,virus and helminthes by enhancing innate immune response of mouse, stimulation of polysaccharide is not likely to result in long-lasting immune memory and special high affinity IgG antibody in immune system. Polysaccharides are usually connected with some protein carriers in order to stimulate immune system producing high affinity IgG antibody . Zwitterionic polysaccharide is a different antigen from the other polysaccharides because it can be presented by antigen presenting cell and stimulate the Th cell and induce the expression of special IgG antibody. In this work, the immune characteristics of zwitterionic polysaccharide was studied through comparing immune behaviors of zwitterionic polysaccharide with that of neutral polysaccharide and artificial synthesized glycoprotein in antibody and cell level in vitro and in vivo..In the experiment, sulfated glucosaminoglycan with both negative and positive charge, and glycoprotein with protein carrier are synthesized successfully. The results were showed that sulfated degree of zwitterionic polysaccharide is 0.90 and aminoacyl concentration of zwitterionic polysaccharid is 35.04ug/ml, which suggest that zwitterionic polysaccharide is modified by both negative and positive charge. Glycoprotein which is synthesized by connecting polysaccharide with BSA using epoxy reagent is assayed by SDS-PAGE electrophoresis and HPLC.The proliferation results of mouse splenic cell which separated from immunized mouse by different ionic polysaccharides respectively, such as 20,000 and 270,000 neutral polysaccharides, zwitterionic polysaccharides and glycoprotein are shown that zwitterionic polysaccharides not only promote different splenic cell proliferation but also stimulate expression of TLR4, TLR9 and TNFαin cells.Antibody formed cell (AFC) production stimulated with various ionic polysaccharides is investigated Zwitterionic polysaccharides could stimulate body to produce antibodies of IgM and IgG in a high level, while only IgM is expressed after neutral polysaccharides immunized the mouse.