Featured Research

from universities, journals, and other organizations

Gene Therapy Frees Two Children From Sterile "Bubbles," Science Authors Report

Date:
May 1, 2000
Source:
American Association For The Advancement Of Science
Summary:
French researchers have developed a method of gene therapy to treat human severe combined immunodeficiency (SCID) X1, a life-threatening disease inherited on the X chromosome. Usually, patients with SCID are forced to live within tightly controlled and sterile "bubbles" to avoid any threats to their nonexistent immune systems until a bone marrow transplant is attempted.

Washington D.C. -- French researchers have developed a method of gene therapy to treat human severe combined immunodeficiency (SCID) X1, a life-threatening disease inherited on the X chromosome. Usually, patients with SCID are forced to live within tightly controlled and sterile "bubbles" to avoid any threats to their nonexistent immune systems until a bone marrow transplant is attempted. The new therapy is described in the 28 April issue of Science.

Related Articles


Two infants, aged 8 and 11 months, were the beneficiaries of this treatment, which provides a normal copy of the defective gene that causes SCID X1 that quickly proliferates within the patient's body. The new gene "unblocks" the development of other immune cells, restoring the immune system to normal functioning. The infants' return to a normal immune system has lasted over eleven months without side effects, says study co-author Alain Fischer of the Hospital Necker in Paris. The Science report notes that a third patient is experiencing similar progress four months after the gene transfer.

The defective gene encodes part of a cell receptor that sends out signals to the parents of T and NK cells, crucial components of the immune system that destroy invaders and rally other immune defenses. Without this gene's direction, these cells do not develop, grow, or spread, and SCID X1 patients are left fatally vulnerable to even slight infectious insults to the body such as a cold sore or common childhood diseases like chicken pox.

The researchers began the therapy by harvesting bone marrow from the patients and sorting out a set of blood stem cells from the marrow. After bathing in a growth factor in containers coated with a fibronectin fragment, a threadlike protein that encourages efficient gene transfer, the cells were infected with a retrovirus carrying the replacement gene. After three days of repeated infection, the scientists transplanted the cells back into the patients without any prior drug treatment. "It was important to show success in the absence of any chemotherapy," explains Fischer.

As early as 15 days later, he and his colleagues detected new cells bearing the correct version of the gene, along with rising numbers of fully functional and diverse immune cells. Currently, the two patients have T, B, and NK cell counts comparable to normal children of their age. The scientists also tested the patients' rebounding immune systems with tetanus, diphtheria, and polio vaccinations, and found that the infants produced the correct antibodies for each.

Fischer believes that the key to the therapy's success lies "not in the technique, but in the disease itself." In the SCID X1 cases, cells with the normal gene seem to enjoy a significant selective advantage, multiplying rapidly until their numbers overwhelm their mutated cousins. Researchers had an inkling of this advantage when one faulty version of the gene spontaneously reversed itself in a previous SCID X1 patient, leading to a lasting rally of the patient's immune system. "This means that even a poorly efficient gene therapy technique--one that only introduces a few cells with the right gene--may work as a treatment," says Fischer, who notes that this might bode well for the success of this therapy for other genetically similar immune diseases.

According to the study, the two young SCID X1 patients have experienced "striking" clinical improvements. No longer in protective isolation, they both live at home without any treatment, enjoying normal growth and development for their ages. Ideally, Fischer says, the children will be monitored for the rest of their lives, both to ensure their continued health and to monitor the long-term success of the therapy.


Story Source:

The above story is based on materials provided by American Association For The Advancement Of Science. Note: Materials may be edited for content and length.


Cite This Page:

American Association For The Advancement Of Science. "Gene Therapy Frees Two Children From Sterile "Bubbles," Science Authors Report." ScienceDaily. ScienceDaily, 1 May 2000. <www.sciencedaily.com/releases/2000/05/000501081423.htm>.
American Association For The Advancement Of Science. (2000, May 1). Gene Therapy Frees Two Children From Sterile "Bubbles," Science Authors Report. ScienceDaily. Retrieved October 31, 2014 from www.sciencedaily.com/releases/2000/05/000501081423.htm
American Association For The Advancement Of Science. "Gene Therapy Frees Two Children From Sterile "Bubbles," Science Authors Report." ScienceDaily. www.sciencedaily.com/releases/2000/05/000501081423.htm (accessed October 31, 2014).

Share This



More Health & Medicine News

Friday, October 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

U.S. Ebola Response Measures Demonstrated

U.S. Ebola Response Measures Demonstrated

AP (Oct. 31, 2014) Officials in the Washington area showed off Ebola response measures being taken at Dulles International Airport and the National Institutes of Health. (Oct. 31) Video provided by AP
Powered by NewsLook.com
Fauci Says Ebola Risk in US "essentially Zero"

Fauci Says Ebola Risk in US "essentially Zero"

AP (Oct. 30, 2014) NIAID Director Anthony Fauci said the risk of Ebola becoming an epidemic in the U.S. is essentially zero Thursday at the Washington Ideas Forum. He also said an Ebola vaccine will be tested in West Africa in the next few months. (Oct. 30) Video provided by AP
Powered by NewsLook.com
Nurse Defies Ebola Quarantine With Bike Ride

Nurse Defies Ebola Quarantine With Bike Ride

AP (Oct. 30, 2014) A nurse who vowed to defy Maine's voluntary quarantine for health care workers who treated Ebola patients followed through on her promise Thursday, leaving her home for an hour-long bike ride. (Oct. 30) Video provided by AP
Powered by NewsLook.com
Pot-Infused Edibles Raise Concerns in Colorado

Pot-Infused Edibles Raise Concerns in Colorado

AFP (Oct. 30, 2014) Colorado may have legalized marijuana for recreational use, but the debate around the decision still continues, with a recent - failed - attempt to ban cannabis-infused edibles. Duration: 01:53 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins