An improved HAdV-41 E1B55K-expressing 293 cell line for packaging fastidious adenovirus.

Human adenovirus type 41 (HAdV-41) is difficult to cultivate under laboratory conditions. Tripartite leader sequence (TPL) of HAdV-41 was cloned, inserted into eukaryotic expression plasmid, and used to establish a HAdV-41 E1B55K-transduced cell line (293TE7). HAdV-41 E1B55K was expressed more abundantly in 293TE7 than in 293E12, an HAdV-41 E1B55K-expressing cell line developed previously. After being infected with E1-deleted HAdV-41 vector (HAdV-41-GFP), 293TE7 synthesized more viral genomic DNA and structural proteins, which led ultimately to a significant increase of the yield of progeny viruses. Typically, 293TE7 produced progeny viruses 3-15 times more than 293E12 did, depending on the amount of seed viruses and culture time. These data demonstrated that 293TE7 was an effective packaging cell line, and implied its application for wild-type HAdV-41 isolation, HAdV-41 virological study and recombinant HAdV-41 construction.