Navigation Links
One shot of gene therapy spreads through brain in animal study
Date:10/8/2007

By targeting a site in a mouse brain well connected to other areas, researchers successfully delivered a beneficial gene to the entire brainafter one injection of gene therapy. If these results in animals can be realized in people, researchers may have a potential method for gene therapy to treat a host of rare but devastating congenital human neurological disorders, such as Tay-Sachs disease.

Researchers from The Childrens Hospital of Philadelphia and the University of Pennsylvania reported their findings in the September 12 issue of the Journal of Neuroscience.

After a single injection, this technique succeeded in correcting diseased areas throughout the brain, said study leader John H. Wolfe, V.M.D., Ph.D., a neurology researcher at The Childrens Hospital of Philadelphia and a professor of pathology and medical genetics at the Penn School of Veterinary Medicine. This may represent a new strategy for treating genetic diseases of the central nervous system.

Wolfe and Penn graduate student Cassia N. Cearley performed the study in mice specially bred to have the neurogenetic disease mucopolysaccharidosis type VII (MPS VII). In people, MPS VII, also called Sly syndrome, is a rare, multisystem disease causing mental retardation and death in childhood or early adulthood.

Sly syndrome is one of a class of some 60 disorders called lysosomal storage diseases that collectively cause disabilities in about one in 5,000 births. Those diseases account for a significant share of childhood mental retardation and severe, often fatal, disabilities. In each of the lysosomal storage diseases, a defect in a specific gene disrupts the production of an enzyme that cleans up waste products from cells. Cellular debris builds up within cell storage sites called lysosomes, and the waste deposits interfere with basic cell functions. Other examples of lysosomal storage diseases are Tay-Sachs disease, Hunter disease and Pompe disease.

In some types of the lysosomal storage disorder Gaucher disease, physicians can supply the missing enzyme to patients and successfully relieve disease symptoms. However, for Sly syndrome and most other lysosomal storage diseases, enzyme replacement, when available, is not very effective in treating the brain component of the disease. Enzymes delivered to the circulation do not cross the blood-brain barrier very well, said Dr. Wolfe.

Therefore, some strategies for treating these diseases have focused on gene therapydelivering DNA sequences that can enter cells and produce the needed enzyme. Researchers have also sought to deliver gene therapy directly to the brain rather than to the bloodstream, but there are practical limitations to making multiple injections into a childs brain.

In the current study, Wolfe targeted a particular region of the mouse brain called the ventral tegmental area (VTA), which has numerous connections with the rest of the brain. He used a neutralized virus called adeno-associated virus (AAV) as a vectorthe delivery vehicle for the gene that carries coded instructions to produce the desired enzyme.

We found that one subtype of AAV was particularly effective for transporting the gene, said Wolfe. The neural pathways carried the virus throughout the brain, where the gene produced the enzyme. The enzyme then cleaned up the storage lesions to the point that these storage lesions were indistinguishable from those found in the brains of normal mice. One advantage of lysosomal enzymes, said Wolfe, is that cells receiving the delivered gene secrete beneficial enzymes to neighboring cells, creating a sphere of correction.

The level of correction resulting from a single injection was unprecedented, said Wolfe, but he cautioned that direct human treatments might be years away. In future studies, he will investigate whether this technique is effective in animals larger than mice. Such results might conceivably resemble a 2005 study in which Wolfe used gene therapy to successfully treat another lysosomal storage disease, called alpha-mannosidosis, in cats. In that study, a treated cat showed dramatic improvement in walking, compared to an untreated cat with the disease.

If the animal results can be successfully extrapolated to humans, Wolfe estimates that 2 milliliters of injected gene therapy might treat a one-year-old child. That amount might be administered with a reasonably limited number of injections, he added, although a great deal of work would be needed to reach that goal.

Grants from the National Institutes of Health supported this research.


'/>"/>
Contact: John Ascenzi
Ascenzi@email.chop.edu
267-426-6055
Children's Hospital of Philadelphia
Source:Eurekalert

Related medicine news :

1. Cancer Doctors Okays Controversial Prostate Therapy
2. Consensus on "Combination Therapy" for Breast Cancer
3. Acupuncture May Help Chemotherapy Side Effects
4. Antioxidants protect health tissue in people undergoing radiation therapy.
5. Distraction therapy found very effective in postoperative patients
6. Gene Therapy shows promise in treating Hemophilia
7. "Make AIDS Therapy affordable" - Physicians demand
8. Acupuncture superseeds massage therapy for short term relief of pain
9. Hormone replacement Therapy a headache
10. Simple Therapy
11. Ovarian cancer in relationship with Hormone therapy
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:12/2/2016)... ... ... With the number of pain management programs available for people suffering with constant ... works for them. When an inventor from Suisun City, Calif., was unsuccessful in finding ... it with others. , He developed a prototype for PRO GO MASSAGE to relieve ...
(Date:12/2/2016)... ... December 02, 2016 , ... CloudLIMS.com, a class-leading provider of ... Lite. CloudLIMS Lite helps biobanks, clinical, research and testing laboratories keep track of ... new version is a faster and a more efficient product, allowing batch processing ...
(Date:12/2/2016)... ... 2016 , ... Yisrayl Hawkins, at The House of Yahweh in Abilene, Texas, ... Bible Prophecy. Yisrayl says this generation, known as the Last Generation, started in 1934 ... details line up exactly with Bible Prophecy – a protected way for those who ...
(Date:12/2/2016)... ... December 02, 2016 , ... Date aired: November 28, ... 2 Diabetes: The Owner’s Manual, http://realtimepressrelease.com/press-releases-tagged-with/daryl-wein , Sharon Kleyne, America’s ... Global Climate Change and Your Health radio program syndicated on Voice of America, ...
(Date:11/30/2016)... Wisconsin (PRWEB) , ... November 30, 2016 , ... ... in the 2016 Deloitte Wisconsin 75, an annual ranking and recognition of the ... year on the list, having ranked from 2008-2016. In addition, Standard Process was ...
Breaking Medicine News(10 mins):
(Date:12/2/2016)... Dec. 2, 2016 CVS Health Corporation (NYSE: ... Day in New York City on Thursday, December 15, 2016, beginning at 8:00 ... team will provide an in-depth review of the company,s ... The company will also discuss 2017 earnings guidance during ... of the event will be broadcast simultaneously on the ...
(Date:12/2/2016)... 2, 2016 Lianluo Smart Limited (Nasdaq: ... Company") which develops, markets and sells medical devices ... China and international markets, recently attended ... Treatment New Progress Forum, co-hosted by the Institute ... , Guangdong Provincial People,s Hospital and Cardiology ...
(Date:12/2/2016)... , December 2, 2016 On ... down 1.36%; the Dow Jones Industrial Average edged 0.36% higher, ... 2,191.08, down 0.35%. Losses were broad based as six out ... has initiated research reports on the following Services equities: Myriad ... QGEN ), INC Research Holdings Inc. (NASDAQ: ...
Breaking Medicine Technology: