Construction and in vitro Pharmacodynamics of Human Interleukin 21 Eukaryotic Expression Plasmid

Objective To develop effective eukaryotic expression plasmids,pVAX/IL-21,and perform the evaluation study on in vitro transfection experiment.Methods Interleukin 21(IL-21) genes were amplified by PCR technique,and then subcloned into eukaryotic expression palsmid pVAX1 by double enzymes and ligase.The new plasmids were analyzed by endonuclease restriction and DNA sequencing.The constructed plasmids were transfected into COS-7 cells in vitro with reagent LipofectamineTM 2000.The expression was quantified by ELISA.Results The gene segments and direction of pVAX1/IL-21(pIL-21) were inserted right.Protein IL-21 can be quantified by ELISA at 24h,48h,72h and 96h after transfection,and arrived at the top level(45ng/ml) at 48 hours after transfection.Conclusion The plasmids pIL-21 was successfully constructed and had strong in vitro cell transfection activity.The experiment lays a foundation for deep research of IL-21's biological function such as antitumor activity.