Objective        To construct a recombinant adenovirus Ad5F11p encoding promoter of telomerase reverse transcriptase (TPEGFp) and evaluate its efficiency in the transfection of UT-7/Epo cells.       Methods       A novel plasmid pAd5F11p-TPEGFp was constructed by molecular cloning. The recombinant adenovirus Ad5F11p-TPEGFp was packaged in HEK293 cells after transfection. The infectious titer of the identified recombinant adenov

irus was determined by limiting dilution assay on HEK293 cells after purified by double CsCl density gradient ultracentrifugation. The recombinant adenovirus Ad5F11p-TPEGFp encoding green fluorescence protein (GFP) gene was transferred into human leukemic cell lines UT-7/Epo cells. The gene transduction efficiency was determined by fluorescence-activated cell sorting assay by flow cytometry. The lysates of UT-7/Epo cells which infected with the recombinant adenovirus were prepared by three cycles of freeze and thaw and used to infect fresh HEK293 cells

and the expression of GFP was observed in 48 h after infection with flow cytometry.       Results       The recombinant adenovirus was successfully prepared and the infectious titer of the virus was 2×10

10

IU/ml. The recombinant adenovirus was significantly more effective than control Ad5GFp in the infection of UT-7/Epo cells. At 200 MOI

Ad5F11p-TPEGFp transduced about 98.2% UT-7/Epo cells

while Ad5GFp only transduced less than 30% at 200 MOI. GFP was observed in UT-7/Epo cells when infected with Ad5F11p-TPEGFp

and GFP was also seen in the fresh HEK293 cells which infected by lysate of UT-7/Epo cells．      Conclusion       The recombinant adenovirus pAd5F11p-TPEGFp is successfully constructed which can infect UT-7/Epo cells effectively and replicate in UT-7/Epo cells.