Immunofluorescence staining for human F.IX on liver sections from treated and untreated hemophilic mice. (A) Untreated C57B1/6 hemophilic mouse. (B) Treated C57B1/6 hemophilic mouse 2 weeks after Ad-F.IX injection. (C) Treated CD-1 hemophilic mouse 2 weeks after Ad-F.IX injection. Original magnification ×200.