FIG. 3.

Inoculation history and follow-up of chimpanzee X0190. (A) X0190 was inoculated intravenously with a 10⁴ dilution of serum from X0234 (HCV RNA titer = 5 × 10⁴ genomes/ml), followed 5 weeks later by a 10³ dilution of this serum, shown on the chart as week 0. Solid bars indicate the HCV RNA titers in serum; the shaded area indicates the ALT level in serum. Above the chart are shown the histology results from the four biopsies, denoted by arrows at weeks 4, 7, 10 and 13; intrahepatic IFN-α, IFN-γ, and IL-4 levels relative to GAPDH RNA as determined by TaqMan assay; qualitative HCV RT-PCR results (sensitivity = 100 genomes/ml); and anti-HCV EIA 2.0 data. (B) T helper proliferation data for several HCV antigens. An SI of >4.0 (dotted line) was considered positive. (C) IFN-γ ELISpot assay of peripheral blood T-cell responses. SFU, spot-forming units. The number of spot-forming units for each antigen or peptide is shown after subtraction of the number of spots in the absence of antigen or peptide. A finding of more than 10 spot-forming units (dotted line) was considered positive.