Study On Recombinant Interleukin-2 Of Gushi Chicken Used As Immunopotentiator

In this study, Chichens inoculated by using recombinant GSIL-2 expressed in E.coli with NDV oil vaccine and chicken Shigellae vaccine were used to study the effect of recombinant GSIL-2 as immunopotentiator. Three series experiments were carried out in this study.Series 1 The recombinant bacteria which was pET28a-GSIL-2/BL₂₁(DE₃) was induced with IPTG.. SDS-PAGE illuminated that the expressed protein was about 18 kD, which accoucted for 18% of total protein of host cell. Recombinant protein was extracted roughly from dissolved BL₂₁ and purified by Ni²⁺ affinity column. The biological activitiy of the rChIL-2 measured by concanavalin A (ConA) induced lymphocyte proliferation assay using MTT. The result indicated that the rChIL-2 had ability to cause both activation and proliferation of T cells in vitro.Series 2 Effect of recombinant GSIL-2 on NDV oil vaccine as immunopotentiator. In the experiment, 200 chichens were randomly divided into five groups (40 chickens each group, male and female accounted for half respectively): control group, NDV oil vaccine group, NDV oil vaccine+ IL-2(10 ug) group, NDV oil vaccine+ IL-2(50 ug) group and NDV oil vaccine+ IL-2(250 ug) group. Ten chickens of each group were used to challenge and protection test. Through challenge and protection test, indexes of immunity organs, antibody level in serum and T cell subsets in peripheral blood, the results indicated that rIL-2 could improve immune protection for NDV oil vaccine and elevate antibody level in serum, CD3⁺, CD4⁺, CD8⁺ T cell subsets in peripheral blood, the ratio of CD4⁺/CD8⁺ T cell and indexes of immunity organs (partly P<0.05).Series 3 Effect of recombinant GSIL-2 on chicken Shigellae vaccine as immunopotentiator. In the experiment, 200 chichens were randomly divided into five groups (40 chickens each group, male and female accounted for half respectively): control group, chicken Shigellae vaccine group, chicken Shigellae vaccine + IL-2(10 ug) group, chicken Shigellae vaccine+ IL-2(50 ug) group and chicken Shigellae vaccine+ IL-2(250 ug) group. Ten chickens of every group were used to challenge and protection test. Through challenge and protection test, indexes of immunity organs, antibody level in serum and T cell subsets in peripheral blood, the results indicated...