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Published on: March 12, 2018
Long-term phenotypic correction in factor IX knockout mice by using ΦC31 integrase-mediated gene therapy.
1Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA.
Gene Therapy
|March 18, 2011
Summary
Gene therapy using the ΦC31 integrase system shows promise for hemophilia B. This method achieved sustained therapeutic levels of human coagulation factor IX (hFIX) in mice, correcting bleeding disorders.
Area of Science:
- Biotechnology
- Gene Therapy
- Hematology
Background:
- Hemophilia B is a genetic bleeding disorder due to Factor IX (FIX) deficiency.
- Current gene therapy for hemophilia B faces challenges in achieving sustained therapeutic factor expression.
Purpose of the Study:
- To evaluate the ΦC31 integrase system for sustained expression of human FIX (hFIX) in a hemophilia B mouse model.
- To assess the safety and efficacy of this gene therapy approach.
Main Methods:
- Delivery of plasmids encoding ΦC31 integrase and hFIX to the liver of FIX knockout mice via hydrodynamic tail vein injection.
- Monitoring of hFIX levels, FIX activity, and phenotypic correction over a 6-month period.
- Immunohistochemistry and genomic analysis to confirm hFIX expression and integration.
Main Results:
- Prolonged therapeutic levels of hFIX were achieved in the mouse model for 6 months.
- Sustained FIX activity and correction of bleeding phenotype were observed in treated mice.
- Sequence-specific genomic integration of the hFIX plasmid was confirmed in hepatocytes.
Conclusions:
- The ΦC31 integrase system enables robust and sustained hFIX expression, offering a potential gene therapy strategy for hemophilia B.
- This approach may translate to successful gene therapy in humans for hemophilia B.
