Persistent and therapeutic FVIII expression following systemic injection of GP64/AlbE/AAT-ΔΔhFVIII vector. About 5 × 108 TU (real-time PCR titer) GP64-pseudotyped FIV vector encoding hFVIII driven by the AlbE/AAT promoter was injected via the tail vein into hemophilia A mice over 2 consecutive days. (A) hVIII levels were measured by ELISA at the time points indicated (n = 5, mean ± SE). Results shown are representative of 2 independent experiments with 5 experimental mice per group. (B) Quantitation of blood loss over 45 minutes following tail vein cutting in wild-type mice (n = 4), FVIII–/– mice (n = 4), and FVIII–/– mice that received GP64/AlbE/AAT-ΔΔhFVIII (FIV/hFVIII, n = 10). Results shown are mean ± SE. FIV-treated animals showed significantly less blood loss (P < .03). (C) Functional hFVIII activity as assessed by Coamatic chromogenic assay. Results contrast wild-type mice, FVIII null mice, and FVIII null treated with GP64/AlbE/AAT-ΔΔhFVIII. Results shown are mean ± SE; *P < .05 when compared with untreated FVIII null mice; 4 to 5 mice per group.
