Change Of IL-2 Receptor A Chain MRNA In Chicken Infected With Eimeria Tenella

Avian coccidiosis is a cytoplastic entozoic parasite disease and may cause severeeconomic loss to the industry of poultry, cell-mediated immunity plays a chief role inprotecting chicken from coccidiosis. Interleukine-2(IL-2) secreted by activated T-cells is anessential cytokine for mediation of cell-mediated immunity. It plays a important role inmediating immune cells by combining with its receptor (IL-2R) secreted in targeted cellmembrane. So that IL-2R plays a key role in activation of the lymphocyte. It was reportedthat IL-2 is in fast association with expansion of activated T-cells and anti-coccidiosis. Still norecognized paper on Coccidiosis-induced changes in chicken IL-2R mRNA expression. For that,Changes in interleukin-2 receptor alpha (IL-2Rα) chain mRNA expressed in immune organs ofchicken infected with Eimeria tenella was studied,The nucleotide sequence encoding mature protein of chicken interleukin-2 receptoralpha (chIL-2Rα) chain was obtained from chicken spleen lymphocyte by RT-PCR. Theidentity of chIL-2Rαto that in GenBank at nucleotide and amino acid level was 99.2% and99.5%respectively. ChIL-2Rαhad a low identity to those of other mammalian, rangingfrom 29.6% to 54.5% at nucleotide level and from 18.8% to 28.0% at amino acid level.Matured protein of chIL-2Rαwas constituted by exchcellular domain(164aa),transmembrane domain (22aa) and introcellular domain(4aa). The 4～21 amino acidresidues of N-end and 194～212 of C-end of chIL-2Rαprotein were hydrophilicity plot,middle of it were hydrophobic property, cDNA encoding chIL-2Rα(exchIL-2Rα)extracellular domain was amplified and subcloned into the expression vector pET32a(+).ExchIL-2R-pET32a was expressed in E.coli Rosseta^TM(DE3), whose magnitude was 34ku.To observe the change of chicken inerleukine-2 receptor a chain (chIL-2Rα) mRNAlevels of chicken infected with Eimeria tenella, blood, tonsil of caecal, spleen and bursa ofFabricius samples were collected aseptically from chicken on day 1, 3, 5, 7 post infectionwith Eimeria tenella. Lymphocyte of them was separated and divided into two portions. Onewas cultured in vitro with ConA, another without ConA. RNA of the cells was collected. Semi-quantitative reverse transcription (RT)-PCR was employed to test the synthesis ofmRNA of chIL-2Rα,β-actin was used as internal standard. The results of groups infectedwith Eimeria tenella showed that: IL-2Rαlevels in serum, spleen and tonsil of caecallymphocyte increased significantly on day 5 post infection versus control groups(P＜0.05),and reach a peak on day 7 post infection. Fabricius IL-2Rαincreased significantly on day 5post infection versus control groups (P＜0.05). IL-2Rαlevels in lymphocyte of organs frominfected chicken stimulated with ConA showed that: chIL-2Rαlevels in spleen and tonsilof caecal lymphocyte decreased significantly post infection versus control groups (P＜0.05).Spleen and serum IL-2Rαincreased significantly on day 3 post infection versus controlgroups (P＜0.05), A peak in IL-2Rαwas noted to be significantly greater in infected versuscontrol groups (P＜0.05). IL-2Rαin Tonsil of caecal increased significantly on day 7 postinfection versus control groups (P＜0.05). Bursa IL-2Rαincreased significantly on day 5post infection, and decreased on day 7(P＜0.05).