Of Porcine Interleukin 15 (il-15) Cloning And Integration Of Thymosin ¦Á1 Expression

Interleukin 15(IL-15) was originally discouvered as a T cell stimulatiory activity present in the culture supernatants of a simian kidney epithelial line,CV-1/EBNA.is a novel cytokine,that shares biological activities with IL-2 and like IL-2,is a member of theα-helix bundlle cytokine family.Then,it was found that IL-15 has a variety of biologicalfunctions,including stimulation of the proliferation of activated T cells,enhancement of the activity of NK cells,induction of granulocyte-macrophage colonystimulating factor.Additonal studies will be needed to determine more identification of IL-15,for it plays an unreplacement role in natrual immunity.The thymus produces several polypeptides,which induce lymphocyte differentiation in vitro and in vivo by Goldestein in 1965.Thymosin fraction 5 contains a family of polypeptides with varying biological activities.Then in 1972,efforts in the thymosin research program are involved in further chemical characterization of thymosin peptides mainly between 1 and 15KD and evaluation of clinical immunotherapeutic protocols.Recent clinical studies with thymosin fraction 5 have shown therapeutic potentials for treatment of patients with primary immunodeficiency diseases and cancer..Although thymusα1 has wide prospects,it is hard to express in gene tools for its small genes,its half-period is extremely short,and it is limited in Large-scale production.Based on these studies,we choose the subjects about the IL15 and thymosinα1.at At present,it has progress in human IL-15 studies,however,it is vain in porcine il-15.there was not any reports about the porcine IL-15 expression in vitro.We foucus on the cloning the gene of porcine IL-15 and expressing in the Escherichia.coli.in order to study the bioactivity of IL-15 and seek a new drug to antiviral therapy.In this study,according to the the theory of overlapping PCR,and the sequence of porcine IL-15 in the GenBank,we sucessfully clone the gene of porcine IL-15 and construct the higher expression systems of in Escherichia coli Rosetta(DE3).Recombinant interleukin-15 were induced by temperate change and it exist by the form of inclusion bodyThe genes of porcine IL-15 and thymosinα1 are connected by the G/S linker,we construct expression systems of in Escherichia coli Rosetta(DE3) to produce the fusion protein.It can competlely hold the activity of protein of porcine IL-15 and thymosinα1,regulate the level of expression of IL-15 and improve and the half-pe riod of thymosinα1.