Corporate Banner
Satellite Banner
Immunology
Scientific Community
 
Become a Member | Sign in
Home>News>This Article
  News
Return

New Gene Therapy Proves Promising as Hemophilia Treatment

Published: Wednesday, December 18, 2013
Last Updated: Wednesday, December 18, 2013
Bookmark and Share
Researchers package specialized blood platelets with genes that express clotting factor, leading to fewer bleeding events.

Researchers at the UNC School of Medicine and the Medical College of Wisconsin found that a new kind of gene therapy led to a dramatic decline in bleeding events in dogs with naturally occurring hemophilia A, a serious and costly bleeding condition that affects about 50,000 people in the United States and millions more around the world.

Before the gene treatment, the animals experienced about five serious bleeding events a year. After receiving the novel gene therapy, though, they experienced substantially fewer bleeding events over three years, as reported in the journal Nature Communications.

“The promise and the hope for gene therapy is that people with hemophilia would be given a single therapeutic injection and then would express the protein they are missing for an extended period of time, ideally for years or even their entire lifetimes,” said Tim Nichols, MD, director of the Francis Owen Blood Research Laboratory at UNC and co-author of the paper. The hope is that after successful gene therapy, people with hemophilia would experience far fewer bleeding events because their blood would clot better.

People with hemophilia A lack the coagulation factor VIII in their blood plasma – the liquid in which red, white, and platelet cells are suspended.

“Bleeding events in hemophilia are severe, and without prompt factor VIII replacement, the disease can be crippling or fatal,” said Nichols, a professor of medicine and pathology. “The random and spontaneous nature of the bleeding is a major challenge for people with hemophilia and their families.”

In underdeveloped countries, people with hemophilia and many undiagnosed people typically die from bleeding in their late teens or early 20s. In developed countries, patients usually live fairly normal lives, as long as they receive preventive injections of recombinant protein therapy a few times a week. The disease requires life-long management that is not without health risks. The annual cost of medications alone is about $200,000 a year.

However, about 35 percent of people with hemophilia A develop an antibody response that blocks the factor VIII therapy. They require continuous infusions of various protein factors and they face a higher mortality rate. Also, the cost of treatment can easily rise to $2 million or more a year per patient.

Nichols and David Wilcox from the Medical College of Wisconsin figured out a potential way around the antibody response in dogs with naturally occurring hemophilia A.

Using a plasmapheresis machine and a blood-enrichment technique, the research team isolated specific platelet precursor cells from three dogs that have hemophilia A. The team then engineered those platelet precursor cells to incorporate a gene therapy vector that expresses factor VIII. The researchers put those engineered platelet precursors back into the dogs. As the cells proliferated and produced new platelets, more and more were found to express factor VIII.

Then, nature took over. Platelets naturally discharge their contents at sites of vascular injury and bleeding. In this experiment, the contents included factor VIII.

In the 2 1/2 years since the dogs received the gene therapy, researchers found that factor VIII was still being expressed in platelets that were coursing throughout the vascular systems of all three dogs. All three experienced much less bleeding. In the dog that expressed the most factor VIII in platelets, the bleeding was limited to just one serious event each year over the course of three years. And such bleeding events were easily treatable with current standard therapies.

“This has been very successful,” Nichols said. “And now we want to explore the possibility of moving it into human clinical trials for people with hemophilia A, similar to what Paul Monahan and Jude Samulski at UNC are currently doing for people with hemophilia B, which is a deficiency of factor IX.”

If approved, the platelet-targeted therapy would likely be restricted to patients who develop the antibody that stifles factor VIII therapy through normal injections. But as the gene therapy is refined, it could become a viable option for people with blood disorders who don’t have inhibitory antibodies.


Further Information
Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 2,500+ scientific posters on ePosters
  • More than 3,700+ scientific videos on LabTube
  • 35 community eNewsletters


Sign In



Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into TechnologyNetworks.com you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.


Scientific News
Researchers Discover Immune System’s 'Trojan Horse'
Oxford University researchers have found that human cells use viruses as Trojan horses, transporting a messenger that encourages the immune system to fight the very virus that carries it.
Researchers Discover New Type of Mycovirus
Virus infects the fungus Aspergillus fumigatus, which can cause the human disease aspergillosis.
Sorting Through Cellular Statistics
Aaron Dinner, professor in chemistry, and his graduate student Herman Gudjonson are trying to read the manual of life, DNA, as part of the Dinner group’s research into bioinformatics—the application of statistics to biological research.
Women’s Immune System Genes Operate Differently from Men’s
A new technology reveals that immune system genes switch on and off differently in women and men, and the source of that variation is not primarily in the DNA.
Experimental MERS Vaccine Shows Promise in Animal Studies
A two-step regimen of experimental vaccines against Middle East respiratory syndrome (MERS) prompted immune responses in mice and rhesus macaques, report National Institutes of Health scientists who designed the vaccines.
HIV Susceptibility Linked to Little-Understood Immune Cell Class
High levels of diversity among immune cells called natural killer cells may strongly predispose people to infection by HIV, and may be driven by prior viral exposures, according to a new study.
New Weapon in the Fight Against Blood Cancer
This strategy, which uses patients’ own immune cells, genetically engineered to target tumors, has shown significant success against multiple myeloma, a cancer of the plasma cells that is largely incurable.
Scientists Create CRISPR/Cas9 Knock-In Mutations in Human T Cells
In a project spearheaded by investigators at UC San Francisco, scientists have devised a new strategy to precisely modify human T cells using the genome-editing system known as CRISPR/Cas9.
Researchers Develop Vaccine that Protects Primates Against Ebola
A collaborative team from The University of Texas Medical Branch at Galveston and the National Institutes of Health have developed an inhalable vaccine that protects primates against Ebola.
Universal Flu Vaccine in the Works
A new study has demonstrated a potential strategy for developing a flu vaccine with potent, broad protection.
SELECTBIO

Skyscraper Banner
Go to LabTube
Go to eposters
 
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
2,500+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
3,700+ scientific videos
Close
Premium CrownJOIN TECHNOLOGY NETWORKS PREMIUM FREE!