Scientists at the Center for Cardiovascular Research at the University of Hawaii John A. Burns School of Medicine hope that patients with hemophilia could one day be treated with gene therapy delivered by tiny bubbles.
The technique could provide an alternative to current treatments for hemophilia, which require frequent injections of a protein, which is expensive and inconvenient.
“We were able to improve clotting in mice for months after a single treatment,” said Ralph Shohet, MD, professor of medicine and director of the center.
Hemophilia affects about 20,000 men and boys in the United States and perhaps 400,000 worldwide. 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 express therapeutic genes, and are then injected into the bloodstream. As the bubbles pass through the liver, a beam of ultrasound pops them, 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 noninvasively 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.