In Utero Gene Therapy (IUGT) Using GLOBE Lentiviral Vector Phenotypically Corrects the Heterozygous Humanised Mouse...

Area of Science:

• Hematology
• Gene Therapy
• Developmental Biology

Background:

• Congenital blood disorders like beta-thalassemia pose significant health challenges.
• In utero gene therapy (IUGT) is a potential strategy for treating fetal hematopoietic disorders.
• A humanized mouse model mimicking human beta-thalassemia was utilized.

Purpose of the Study:

• To evaluate the efficacy of IUGT using a lentiviral vector (GLOBE) in a mouse model of beta-thalassemia.
• To assess the long-term hematological, anatomical, and cardiac outcomes post-treatment.
• To analyze vector integration sites in various tissues.

Main Methods:

• Intrahepatic injection of a beta-globin expressing lentiviral vector (GLOBE) into E13.5 fetal mice.
• Analysis of vector copy number in bone marrow, peripheral blood, liver, and spleen at 12 and 32 weeks.
• Assessment of hematological parameters, spleen weight, cardiac function via MRI, and integration site analysis.

Main Results:

• IUGT normalized hemoglobin levels and reduced spleen weight in treated heterozygous mice compared to controls.
• Cardiac function, measured by left ventricular ejection fraction, was significantly improved in treated mice.
• Integration site analysis revealed polyclonal integration, indicating broad gene distribution.

Conclusions:

• GLOBE lentiviral vector-mediated IUGT effectively normalized the hematological and anatomical phenotype in a humanized beta-thalassemia mouse model.
• IUGT demonstrated potential for ameliorating poor cardiac function associated with beta-thalassemia.
• This study supports IUGT as a promising therapeutic approach for congenital blood disorders.