Navigation Links
Correcting sickle cell disease with stem cells
Date:9/28/2011

Using a patient's own stem cells, researchers at Johns Hopkins have corrected the genetic alteration that causes sickle cell disease (SCD), a painful, disabling inherited blood disorder that affects mostly African-Americans. The corrected stem cells were coaxed into immature red blood cells in a test tube that then turned on a normal version of the gene.

The research team cautions that the work, done only in the laboratory, is years away from clinical use in patients, but should provide tools for developing gene therapies for SCD and a variety of other blood disorders.

In an article published online August 31 in Blood, the researchers say they are one step closer to developing a feasible cure or long-term treatment option for patients with SCD, which is caused by a single DNA letter change in the gene for adult hemoglobin, the principle protein in red blood cells needed to carry oxygen. People who inherited two copies -- one from each parent -- of the genetic alteration, the red blood cells are sickle-shaped, rather than round. The misshapen red blood cells clog blood vessels, leading to pain, fatigue, infections, organ damage and premature death.

Although there are drugs and painkillers that control SCD symptoms, the only known cure -- achieved rarely -- has been bone marrow transplant. But because the vast majority of SCD patients are African-American and few African-Americans have registered in the bone marrow registry, it has been difficult to find compatible donors, says Linzhao Cheng, Ph.D, a professor of medicine and associate director for basic research in the Division of Hematology and also a member of the Johns Hopkins Institute for Cell Engineering. "We're now one step closer to developing a combination cell and gene therapy method that will allow us to use patients' own cells to treat them."

Using one adult patient at The Johns Hopkins Hospital as their first case, the researchers first isolated the patient's bone marrow cells. After generating induced pluripotent stem (iPS) cells -- adult cells that have been reprogrammed to behave like embryonic stem cells -- from the bone marrow cells, they put one normal copy of the hemoglobin gene in place of the defective one using genetic engineering techniques.

The researchers sequenced the DNA from 300 different samples of iPS cells to identify those that contained correct copies of the hemoglobin gene and found four. Three of these iPS cell lines didn't pass muster in subsequent tests.

"The beauty of iPS cells is that we can grow a lot of them and then coax them into becoming cells of any kind, including red blood cells," Cheng said.

In their process, his team converted the corrected iPS cells into immature red blood cells by giving them growth factors. Further testing showed that the normal hemoglobin gene was turned on properly in these cells, although at less than half of normal levels. "We think these immature red blood cells still behave like embryonic cells and as a result are unable to turn on high enough levels of the adult hemoglobin gene," explains Cheng. "We next have to learn how to properly convert these cells into mature red blood cells."

Only one drug treatment has been approved by the FDA for treatment of SCD, hydroxyurea, whose use was pioneered by George Dover, MD, the chief of pediatrics at the Johns Hopkins Children's Center. Outside of bone marrow transplants, frequent blood transfusions and narcotics can control acute episodes.


'/>"/>
Contact: Vanessa McMains
vmcmain1@jhmi.edu
410-502-9410
Johns Hopkins Medical Institutions
Source:Eurekalert

Related medicine news :

1. Sickle cell trait is not risk factor for kidney disease
2. Schools failing pupils with sickle cell disease
3. Nitric oxide impacts source of sickle cell pain crisis
4. ENERCA clinical recommendations for sickle cell disease management and prevention in children
5. Young black athletes with sickle cell trait might be susceptible to sudden death
6. Sickle Cell May Be Hidden Danger to Young Athletes
7. 2 studies provide insight into stroke risk and prevention in young sickle cell anemia patients
8. Georgia Tech hosts sickle cell disease symposium
9. Sickle cell treatment developed at LA BioMed enters Phase 3 clinical trial
10. Sickle cell patients should be better monitored for constipation prevention
11. Stroke prevention study in children with sickle cell anemia, iron overload stopped early
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:10/13/2017)... , ... October 13, 2017 , ... “The Journey: From ... every danger possible to save lost souls in the Philippines. “The Journey: From the ... is a dedicated teacher of the Bible. She has taught all ages and currently ...
(Date:10/12/2017)... ... , ... Planet Fitness, one of the largest and fastest growing franchisors and ... flagship location in Covington, LA at 401 N. U.S. Highway 190, in January of ... Depot in the Holiday Square shopping center. Its location allows it to serve both ...
(Date:10/12/2017)... ... 12, 2017 , ... Asante, a nationally recognized health system ... their existing home health joint venture through an agreement, effective October 1, 2017, ... venture home health company with Asante, delivering clinically integrated care, for the past ...
(Date:10/12/2017)... ... October 12, 2017 , ... Leading pediatric oncology experts ... Washington, D.C., for the 49th Congress of the International Society of Paediatric Oncology ... of the Center for Cancer and Blood Disorders at Children’s National, and ...
(Date:10/12/2017)... ... October 12, 2017 , ... In the United States, ... In some states—like New York, New Jersey, Massachusetts, Texas, Virginia, Connecticut, and California—the ... have extremely low property-tax rates, which contributes to the relatively lower cost of ...
Breaking Medicine News(10 mins):
(Date:9/18/2017)... KALAMAZOO, Mich. , Sept. 18, 2017  PMD ... OptiMed Specialty Pharmacy of Kalamazoo, Mich. ... strategic hub service that expedites and streamlines patient and ... Spiro PD 2.0, and wellness management services.  ... medical device used to measure lung function for a ...
(Date:9/12/2017)... , Sept. 12, 2017   EcoVadis , the leading platform for ... the first annual edition of its Global CSR Risk and Performance Index. ... by EcoVadis, based on Scorecard Ratings that analyzed nearly 800,000 data points ... ... ...
(Date:9/9/2017)... ... ... Monday, September 18 th .The Brain Tumor Foundation (BTF) begins a week-long ... BTF,s Mobile MRI Unit – a 70 Ft. ... brings its nationwide initiative, the Road to Early Detection Sponsor-A-City Campaign to ...
Breaking Medicine Technology: