Scientists from the Center for Cardiovascular Research at the University of Hawaii (UH) have developed a novel approach to hemophilia gene therapy that employs microbubbles and an ultrasonic beam to deliver the treatment.
The study was led by Dr. Cindy Anderson and Dr. Chad Walton, who were both studying at UH’s John A. Burns School of Medicine (JABSOM) during the breakthrough phase of research. Anderson at that time was a graduate student in the Cell & Molecular Biology Department at JABSOM and is now an Assistant Professor at Georgetown University. Walton was an Assistant Professor of Medicine at JABSOM and is now an assistant to the Vice-Chancellor for Research at UH Mānoa. Their study was funded by the American Heart Association and the U.S. National Institutes of Health.
The UH team took genetic material that can elicit the production of factor IX (FIX) and placed it within miniscule microbubbles composed of lipid molecules that do not dissolve in water. The therapy was then injected into the bloodstream of mice with hemophilia B. As the microbubbles passed through the bloodstream they were hit by a beam of ultrasound that dispersed the genetic “payload” and deposited it into liver cells targeted for their ability to stimulate the production of FIX. The technique is known as ultrasound-targeted microbubble destruction (UTMD).
The animals subsequently showed both reductions in clotting time and increased FIX levels. An additional set of mice were treated via UTMD and evaluated for long-term effects, the results of which demonstrated a persistent reduction in average clotting time 160 days after one administration of the therapy.
“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 for Cardiovascular Research. Shohet sees unique advantages in UTMD, as it is both non-viral and minimally invasive.
“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.” added Shohet.
The study, “Ultrasound-Targeted Hepatic Delivery of Factor IX in Hemophiliac Mice,” was published in April, 2016, in the journal Gene Therapy
Source: JABSOM news release dated March 10, 2017
