PMC

Anti-AAV8 capsid humoral responses. Anti-AAV8 capsid IgG2 responses were assayed in all 4 dogs. Plasma samples were assayed for capsid-specific IgG2 by ELISA with plates coated with empty AAV8 capsid.

Recovery of cFVIII after intravenous administration. rBDD-cFVIII was administered (100 IU/kg) to Chapel Hill dogs K01 and K03 by intravenous injection, and cFVIII activity was monitored over time by FVIII assay.

Whole-blood clotting time of Chapel Hill inhibitor dogs after vector administration. Whole blood clotting time (WBCT) for all 3 hemophilia A Chapel Hill dogs is shown. The WBCT range for a normal dog is shaded in light gray (8-12 minutes), and the range for a hemophilia A dog is shaded in dark gray (> 45 minutes).

cFVIII expression and anti-cFVIII antibody response in a high-responding hemophilia A dog after AAV-mediated liver expression of cFVIII. A high-responding hemophilia A dog from the Queen's University colony (Wembley) was administered 2.5 × 10¹³ vg/kg of AAV8-TBG-cFVIII-HC and AAV8-TBG-cFVIII-LC by peripheral venous injection. (A) cFVIII antigen levels were assayed by a cFVIII-LC-specific ELISA, and activity was monitored by FVIII assay. (B) Anti-cFVIII antibody responses were measured by anti-cFVIII IgG2 ELISA and Bethesda assays.

cFVIII expression and anti-cFVIII antibody responses in Chapel Hill hemophilia A dog L44 after liver delivery of AAV-cFVIII. One Chapel Hill dog (L44) with preexisting inhibitors to cFVIII was administered 2.5 × 10¹³ vg/kg of AAV8-TBG-cFVIII-HC and AAV8- TBG-cFVIII-LC by peripheral venous injection. (A) cFVIII antigen levels were assayed by a cFVIII-LC specific ELISA, and activity was monitored by FVIII assay. (B) Anti-cFVIII antibody responses were measured by anti-cFVIII IgG2 ELISA and Bethesda assays. Black arrows indicate 4 weekly challenges with 500 U of rBDD-cFVIII.

cFVIII expression and anti-cFVIII antibody responses in Chapel Hill hemophilia A dog K01 after liver delivery of AAV-cFVIII. One Chapel Hill dog (K01) with preexisting inhibitors to cFVIII was administered 2.5 × 10¹³ vg/kg of AAV8-TBG-cFVIII-HC and AAV8-TBG-cFVIII-LC by peripheral venous injection. (A) cFVIII antigen levels were assayed by a cFVIII-LC specific ELISA, and activity was monitored by FVIII assay. (B) Anti-cFVIII antibody responses were measured by anti-cFVIII IgG2 ELISA and Bethesda assays. Black arrows indicate 4 weekly challenges with 500 U of rBDD-cFVIII.

cFVIII expression and anti-cFVIII antibody responses in Chapel Hill hemophilia A dog K03 after liver delivery of AAV-cFVIII. One Chapel Hill dog (K03) with preexisting inhibitors to cFVIII was administered 2.5 × 10¹³ vg/kg of AAV8-TBG-cFVIII-HC and AAV8-TBG-cFVIII-LC by peripheral venous injection. (A) cFVIII antigen levels were assayed by a cFVIII-LC specific ELISA, and activity was monitored by FVIII assay. (B) Anti-cFVIII antibody responses were measured by anti-cFVIII IgG2 ELISA and Bethesda assays. Black arrows indicate 4 weekly challenges with 500 U of rBDD-cFVIII, and gray arrows indicate 4 weekly injections of 25 mL of pooled normal canine plasma per dose.