FIG. 1.

Construction of conditional HCV transgenic mouse lines. (A) The transgene construct was prepared by inserting a 1.4-kb spacer that is flanked by two loxP sequences between the promoter and structural genes. A 1.7-kb PCR fragment is detectable with the primer pair P1-P3 in the transgenic mouse. (B) When a recombinant adenovirus carrying the Cre DNA recombinase was injected, the spacer was removed by recombination between the two loxP sequences, as evidenced by the presence of a 400-bp band amplified by PCR using the same primers. Expression of the HCV core protein at 21 kDa in the liver was detected by Western blot analysis.