Construction and in vitro expression of an eukaryotic plasmid encoding murine IL-5

Objective To construct a eukaryotic plasmid expressing murine interleukine-5 (IL-5) and test whether the plasmid can be expressed in the eukaryotic cell in vitro. Methods The full-length gene of murine IL-5 was amplified by PCR from the clonal plasmid pORF9-mIL-5. Then the murine IL-5 gene was inserted into the eukaryotic-expression plasmid pcDNA3.1(+), the resultant recombinant plasmid was confirmed by restriction endonuclease and sequencing, then designated as pcDNA-mIL-5. The recombinant plasmid pcDNA-mIL-5 was transfected into eukaryotic cell COS by lipofectin. Western blot was used to certify whether the purpose protein was correctly expressed in COS cells. Results The 426 bp DNA sequence of murine IL-5 was correctly amplified. The recombinant pcDNA-mIL-5 was successfully constructed, and it could be correctly expressed in the COS cells. Conclusion This recombinant pcDNA-mIL-5 plasmid will provide a basis for immunogene therapy of allergic asthma.