Figure 1.

Functional FVIII expression in hemophilia A mice. Neonatal FVIII-deficient littermates were injected with concentrated VSV₂₉₃-FVIII vector. Shown are mean plasma FVIII activities (n = 3) of recipient mice with prolonged FVIII expression (mice 1–6 in Table 1 are depicted by ▴, ♦, ●, ■, ▾, and ◂, respectively) and negative control mouse injected with PBS (□).The experiment was repeated twice in two independent batches of animals with different vector lots. Mice 1, 4, and 5 (▴, ■ , and ▾) were injected with 1.4 × 10⁸ cfu/ml, and mice 2, 3, and 6, (♦, ●, and ◂) with 0.9 × 10⁸ cfu/ml VSV₂₉₃-FVIII. Tail-clipping was performed 2 months postinjection except for mice 5 and 6 (3 months). Five of thirteen mice injected with VSV₂₉₃-FVIII vector (9–13, in Table 1) and all control mice injected with PBS (9 of 9) did not yield detectable FVIII.