Research In Immune Response Of Echinococcus Granulosus Infected And EgM9 Protein Immunized Dogs

Currently, the study on the host anti Echinococcus granulosus immunity in home and abroad is mainly concentrated on the host endosomotic immunoprotection, immune evasion and immunologic injury mechanism. There are many study reports on the immune antigen Eg95 of the intermediate host of the Echinococcus granulosus disease, while the study on the immunoprotection antigen of the final host dog is still in progress. This study is through the immunohistochemical method and molecular biological method to research the immune response condition produced in the body periphery immune system and enteric tunica mucosa immune system after the host being infected with Echinococcus granulosus and EgM9 protein immune, in the hope of providing experiment base for researching and developing and preparing relevant clinic vaccine.This study is firstly to make the induced expression to the EgM9 protein through the Escherichia coli (BL-21) which is converted from pET-41b recombinant plasmid, then to analyzes the expression products through SDS-PAGE to prove what is expressed is EgM9 protein in deed, and then to carry out purification to it to obtain the EgM9 recombinant target protein which meets the immune antigen requirements.The experiment dogs are divided into four groups (Group I: EgM9 protein immune group; Group II: group being infected with protoscolex after EgM9 protein immune; Group III: group being directly inflected with protoscolex; Group IV: blank contrast group), to carry out immunity test to the Group I and Group II with purified EgM9 protein, then to do artificial protoscolex infection to the Group II and Group III respectively. After dissecting the experiment dogs and doing inspection, the load worm number calculation is carried out; the result indicates that after immunizing the dogs with EgM9 protein the dogs can obtain some certain immunoprotection effect.To collect mesenteric lymph nodes and small intestines of the experiment dogs, based on principles of the immune enzyme histochemistry and immunofluorescence histochemistry, it is to utilize direct method and antigen-antibody-antibody marker method to carry out inspection. The result of the direct method indicates the mesenteric lymph nodes and small intestines of the Group I, Group II and Group III dogs exist IgG antibody, all of the reactions show positive; the result of the antigen-antibody-antibody marker method indicates the Group I and Group II show positive while the Group III shows negative, under the fluorescence microscope there are apparent fluorescence loca, which indicates this method can make localization inspection to the IgG in the mesenteric lymph nodes and small intestines of the immune dogs.Through Real-Time PCR inspection to the three kinds of cell factors (IL-4, TGF-βand INF-γ) in the mesenteric lymph node and small intestine tissues of the above experiment dogs, it indicates both the IL-4 and the INF-γin the mesenteric lymph nodes and small intestines of the Group I and Group III experiment dogs have apparent change, the number of IL-4 is much high above the INF-γ, while in the Group II, although the number of IL-4 is also higher than that of the INF-γ, the numbers of the IL-4 and INF-γare also higher than that of the other groups at the same time. The results indicate no matter it is to carry out immunization or carry out infection to dogs, they both can cause Th1 type and Th2 type reactions, but they are with Th2 type reaction as main.