Viral loads in different hamster tissues during early stages of infection by SV40.

p.i., postinoculation; SV40, simian virus 40; Und, undetectable.aNumbers represent the average of observed (nonadjusted) results from the tissues analyzed at each time point. See Table 1 for the number of tissues from different animals tested per virus at each time point (usually n = 4). Two or three separate fragments were assayed and the values averaged from each tissue from each animal (see Materials and Methods).bThe inoculum for each virus was 107 plaque-forming units (PFU) per animal by the intracardiac route. The number of SV40 genome DNA copies per PFU varied for each viral stock: 776-WT, 1700; 776-SM1, 130; SVCPC-WT, 1800; SVCPC-SM2, 590. This resulted in the following ratios of viral genome copies inoculated: 776-WT:776-SM1, 13; SVCPC-WT:SVCPC-SM2, 3.cNote that higher viral DNA copy numbers were more often detected in liver and kidney samples from animals exposed to microRNA-negative viruses than in those infected with wild-type viruses, even though fewer viral genome copies were inoculated with the mutants than with the wild-type viruses. This pattern held for most specimen collections through day 45 p.i.