Coagulation assays in E60, a dog treated by ILP without immunosuppression. (A) Canine F.IX antigen levels, (B) activated partial thromboplastin times (aPTTs), and (C) Bethesda assay (titer of neutralizing antibody) as a function of time after vector injection. Dog E60 was injected at 3.9 × 10¹² vg/kg and did not receive immunosuppresion. Gray band in panel B denotes range of normal aPTT; line at 50 seconds denotes hemophilic values.