Study On Anti-periodontitis Immunization With DNA Vaccines PVAX1-kgp And PVAX1-IL-4

Objective:Periodontitis is a infectious disease caused by anaerobic bacteria. It is one of the most important reasons that cause teeth loss in adults. And some other diseases are also related to periodontitis, such as cardiovascular disease and Diabetes mellitus. So the methods how to prevent and cure periodontitis is very important. Then the DNA vaccine is so urgent.P. gis one of the most important pathogenic bacteria of periodontitis. And gingipains K (Kgp) is recognized as a major virulence factor influencing the disease. Kgp has a variety of biological activities, which can affect the bacterial adhesion. It is a good immunogen so it can serve as a kind of important vaccine antigens to prevent and cure the periodontitis. The construction of the DNA vaccine pVAXl-kgp was successful in the early experiments.IL-4is a kind of cytokines.which is secreted by T cells and mast cells. It can stimulate the transformation of B lymphocytes and T lymphocytes which can produce IgE or IgG.This experiment aimed to construct a eukaryotic expression plasmid pVAX1-IL-4. And then inject the DNA vaccine pVAXl-kgp and pVAXl-IL-4into the animal model to observe the effect of protecting periodontitis.Methods: 1. To construct a eukaryotic expression plasmid pVAXl-IL-4.2. Divide the wistar rat into four groups, then inject the DNA vaccine into the animal model by nasal immunization and intramuscular immunization.3. Establish the animal model of periodontitis by orthodontic ligature.4. Samples collected and detect the level of the antibody IgG and slgA.Results:The eukaryotic expression plasmid pVAXl-IL-4was successful constrcted. The pVAXl-kgp was used as DNA vaccine and the antibody IgG、IgA was significantly increased. When pVAX1-IL-4was joined to immune the rats, the lever of antibody IgG was much higher. The alveolar bone loss in sham-immunized group was greater than pVAX1-kgp immunized group, and alveolar bone loss in pVAXl-IL-4pVAX1-kgp co-immunized group was much less than pVAXl-kgp immunized group.Conclusion:The eukaryotic expression plasmid pVAX1-kgp could serve as a treatment of periodontitis. IL-4expressed by eukaryotic expression plasmid pVAXl-IL-4could act as an adjuvant cytokine to enhance the antibody response.