Objective: To construct and sequence eukar yo tic vector with high effective expression for human insulin. Methods: The
recombinant
expression plasmid pEF1α-ImINS was constructed accordi ng to the routine method. Four
recombinant plasmids of insulin were transfectedinto
baby hamster kidney (BHK) cells by using lipofectin reagent. And the expres sion products of insulin gene were detected by using radioimmunoassay (RIA) andimmunohistochemistry when the positive clones were passed to the 20th generation . Then the products of plasmid pEF1α-ImINS were injected into KM mice intraper itoneally to verify whether it has biological effect or not. And the variation o f the concentration of blood sugar was detected 24 hoursbefore injection, 6 an d 72 hours after injection. Results: The highest expression le vel of insulin and/or proinsulin was 7.984μIU/ml detected by RIA. The grey leve l of insulin expressed form pEF1α-ImINS was 177.5±15.10 in cytoplasm, 150.3± 21.43 in nuclear. The statistical analysis showed that the culture medium of BHKcells transfected with pEF1α-ImINS was similar to control group. But the grou p of BHK clone PBS suspension transfected with plasmid pEF1α-ImINS has differe nce between preinjection and postinjection. Conclusion: The ne w recombinant expression plasmid pEF1α-ImINS has the highest expression levelamong the 4 plasmids to express insulin in BHK cells. And the BHK clone cells tr ansfected with pEF1α-ImINS has biological effects.