Abstract: The objective of this study was to construct eukaryotic expression vector of human interleukin-7, and make it expressed in HEK293 cells. IL-7 gene was amplified by PCR from the lentivirus expression vector pLV-CMV-EF1-GPL-rIL-7, and then cloned into the pcDNA3.1 vector to construct eukaryotic expression vector pcDNA3.1-rIL-7. The constructed plasmid was transfected into the HEK293 cells via LipofectamineTM 2000 separately and screened by G418 continuously. By G418 screening and monoclonal, stably secreting expression IL-7 cell line HEK293-rIL-7 was obtained, successfully constructed eukaryotic expression vector pcDNA3.1-rIL-7, and expressed in HEK293 cells. By cell cloning, one cell line with high secretory expression was obtained, named HEK293-rIL7-2G3. The content of IL-7 in the supernatant after 48 h was 3.2 ng/mL. 

Key words: IL-7, transfection, green fluorescent protein, secretory expression