Time course of plasma concentration of hF.IX in hemophilia B mice following intravenous injection of 10¹¹particles Ad-F.IX. Plasma samples were collected at the indicated time points and hF.IX levels determined by ELISA. Each point is an average of duplicate measurements. (A) C57B1/6 hemophilic mice and 1 normal littermate (no. 7). (B) CD-1 hemophilic mice and 1 normal littermate (no. 7). In both cases the normal littermate was treated with the same dose of vector. (□), 1; (◊), 2; (○), 3; (▵), 4; (⊞), 5; (⧫), 6; (•), 7.