Immunologic Enhancement Of Polysaccharide Isolated From The Fruit Of Physalis Alkekengi L. As The Adjuvant Of DNA Vaccine

Physalis alkekengi L. is a member of the family of Solanacese，the fruit can be used asmedicine. It has many functions including anti-inflammatory, anti-cold and anti-cough.The extraction of the fruit（PPSB）can resist cancers and inhibit the growth of mouseEhrlich ascites carcinoma; its fruit juice can inhibit Staphylococcus aureus, Pseudomonasaeruginosa and the antigen on the surface of hepatitis B virus. In recent years, along within-depth study of plant polysaccharides, it was discovered that a lot of plantpolysaccharides have good functions of immune regulation. Our laboratory has studied thebiological activity of PPSB and found that it has significant immune-enhancing effect.We use PPSB that we selected、separated and purified from the water-solubleextraction of Physalis alkekengi L. as the adjuvant of DNA vaccine in this paper. We injectthe animals we used（ICR mice） by the way of intramuscular and electronic transfer. Themice were immunized intraperitoneally two times at14-day interval. Serum obtained fromthe tail veins of immunized mice was analyzed for specific lgG、IgG1and IgG2b by ELISA.Two weeks later we infected the mice with a certain concentration of Candida albicans byinjecting through the tail vein (protective immunization). Continue to keep the mice for15days and observed the mortality of experimental animals during these days. Then removethe kidneys on the right side for grinding.After the appropriate dilution of the slurrycoating on the solid medium culture and then statistics Candida albicans colony counts.The results of ELISA show that: the groups which were injected PPSB andpcDNA3.1/HSP90（DNA vaccine）were induced higher anti-pD–HSP90C specific IgG、IgG1、IgG2b antibodies and IL-4levels than control groups. Protective immunizationresults also shows that the number of Candida albicans colony counts decreasedsignificantly comparing with control groups.This experiment laid a solid foundation for further study of plant polysaccharides usedas a new type of vaccine adjuvants.