Fig 1.

L4-33K mutant virus. (A) Schematic diagram of the Ad5 L4 region. Coding regions for L4-100K, L4-33K, L4-22K, and pVIII are shown. L4-33K mutant virus 33K⁻ is depicted with a stop codon introduced at amino acid position 138 of L4-33K. (B) Complementation of Ad5-WT and 33K⁻ virus in TetC4-33K cells with (OFF) or without (ON) doxycycline (1 μg/ml) in the culture medium. Infected-cell lysates were harvest at 48 hpi and subsequently titrated on TetC4-33K cells cultured without doxycycline by a plaque assay. (C) Growth curves of Ad5-WT and 33K⁻ virus in A549 cells. Infected A549 cell lysates were harvest at 6, 12, 24, and 48 hpi and subsequently titrated on TetC4-33K cells by a plaque assay.