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:2/10/2016)... ... 09, 2016 , ... Traumatic Brian Injury is often in ... one of many possible sources: sports, car accidents, falls, work accidents, combat and ... Rehab Solutions for the Complexities of Concussions is designed for physical and ...
(Date:2/9/2016)... ... 09, 2016 , ... Center for Autism and Related Disorders ... spectrum disorder (ASD). Beginning Jan. 1, 2016, Medicaid is covering autism treatment in ... key to providing effective treatment for individuals with ASD. Now, over 1,800 low-income ...
(Date:2/9/2016)... ... February 09, 2016 , ... URise Products announces today ... device, the StandUp Walker. Made entirely in the USA, the StandUp Walker is ... , StandUp Walker’s novel patent-pending design offers 2-in-1 benefits of a stand-assist ...
(Date:2/9/2016)... (PRWEB) , ... February 09, ... ... print and e-book publishing software, in partnership with Snowfall4pod Digital, creators of ... a comprehensive book publishing, content management, global distribution and print-on-demand network. , ...
(Date:2/9/2016)... ... February 09, 2016 , ... On January 12, 2016 Paul McElwee, a ... they noticed their furnace not producing any heat. Shortly after entering the home, Paul ... exchanger was leaking dangerous levels of carbon monoxide into the home, at 2,000 parts ...
Breaking Medicine News(10 mins):
(Date:2/10/2016)... 10, 2016 --> ... Therapeutics and Companion Diagnostic Market to 2019 - ... Environment" research report indicates that the core personalized ... by 2020 growing at a CAGR of 8.74%. ... and targeted therapeutics and is dominated by oncology, ...
(Date:2/10/2016)... February 10, 2016 Demonstrates ... 1 receptor selectivity   1 ... which has entered clinical development as a new ... and schizophrenia.   --> 1 ... has entered clinical development as a new treatment ...
(Date:2/9/2016)... Inc. (NASDAQ: MSON ), an international surgical ... therapeutic ultrasonic products for spine surgery, skull-based surgery, ... other surgical applications, today announced financial results for ... fiscal year 2016 ended December 31, 2015. ... Highlights for the second quarter and first half ...
Breaking Medicine Technology: