The infectious titre of a virus is defined as the number of infectious virions, determined by the plaque assay method and expressed as (PFU) per ml. In our transduction assays, cells were prepared in 24-well plates containing 105 cells per well. Complexes of adenovirus and baculovirus vectors in the ratio 5:100 PFU respectively, were prepared by preincubation of each virus in a total volume of 100 μl of cell culture media for 1 h at 37 °C. The complexes were then added to the cells and incubated for another hour at 37 °C, after which 200 μl prewarmed media was added to each well and incubated at 37 °C.