UH Med Now
Technique at University of Hawaii Center for Cardiovascular Research uses tiny bubbles to deliver gene therapy for hemophilia
Pictured: Ralph Shohet, MD, in his laboratory at the John A. Burns School of Medicine.
The technique could provide an alternative to current treatments for hemophilia, which require frequent injections of a protein (Factor VIII or Factor IX), which is expensive and inconvenient.
Hemophilia affects about 20,000 men and boys in the United States and perhaps 400,000 world-wide. Most affected individuals have a severe form of the disease and suffer from frequent and spontaneous bleeding episodes that can result in serious complications.
The microbubbles are made of lipid molecules that won’t dissolve in water. The bubbles are made with DNA that expresses therapeutic genes, and are then injected into the bloodstream. As the bubbles pass through the liver they are popped by a beam of ultrasound and the DNA is deposited in the liver cells, where it makes the missing clotting factor. Hemophilia is an attractive target for gene replacement therapy, because the disease results from a single gene mutation, and low levels of the normal protein can restore clotting function.
“Hemophilia is a chronic debilitating disease. If we can treat it simply, cheaply, and non-invasively with gene therapy we will have helped to fulfill the promise of the modern medical era,“ said Dr. Shohet.
The findings were published in the scientific journal Gene Therapy.