Bioengineer Gang Bao uses gene editing to repair up to 40 percent of bone marrow cells from patients
Scientists have successfully used gene editing to repair 20 to 40 percent of stem and progenitor cells taken from the peripheral blood of patients with sickle cell disease, according to Rice University bioengineer Gang Bao.
Bao, in collaboration with Baylor College of Medicine, Texas Children’s Hospital and Stanford University, is working to find a cure for the hereditary disease. A single DNA mutation causes the body to make sticky, crescent-shaped red blood cells that contain abnormal hemoglobin and can block blood flow in limbs and organs.
In his talk at the annual American Association for the Advancement of Science meeting in Austin Feb. 16, Bao revealed results from a series of tests to see whether CRISPR/Cas9-based editing can fix the mutation. His presentation was part of a scientific session titled “Gene Editing and Human Identity: Promising Advances and Ethical Challenges.”
“Sickle cell disease is caused by a single mutation in the beta-globin gene (in the stem cell’s DNA),” he said. “The idea is to correct that particular mutation, and then stem cells that have the correction would differentiate into normal blood cells, including red blood cells. Those will then be healthy blood cells.”
Bao’s lab collaborated with Vivien Sheehan, an assistant professor of pediatrics and hematology at Baylor and a member of the sickle cell program at Texas Children’s, to collect stem and progenitor cells (CD34-positive cells) from patients with the disease. These were then edited in the Bao lab with CRISPR/Cas9 together with a custom template, a piece of DNA designed to correct the mutation.
The gene-edited cells were injected into the bone marrow of immunodeficient mice and tested after 19 weeks to see how many retained the edit. “The rate of repair remained stable, which is great,” Bao said. This engraftment study was carried out in the lab of Matt Porteus, an associate professor of pediatrics at Stanford.
Another major finding of the study is that the CRISPR/Cas9 system could introduce large alterations to the genes in patients’ cells, in addition to small mutations or deletions. These off-target effects could cause a disease.
The findings, part of an upcoming paper, are a step toward treating sickle cell disease. Obstacles in the way of a cure include optimizing the CRISPR/Cas9 system to eliminate off-target effects, as well as finding a way to further increase the amount of gene-corrected stem cells.
Bao pointed out that researchers still don’t know whether repairing as much as 40 percent of the cells is enough to cure a patient. “We’d like to say, ‘Yes,’” he said, “but we don’t really know yet. That’s something we hope to learn from an eventual clinical trial.”
The Latest on: Sickle cell disease
- 22-44% prevalence of sickle cell in Central India: Expert on October 6, 2018 at 2:46 pm
Nagpur: Senior haematologist Dr Dilip Gohokar recalled how 30 years ago, three-to-four patients admitted with sickle cell disease would die every week, and there wasn’t much that could be done ... […]
- ECU to host sickle cell disease awareness event on October 5, 2018 at 9:37 pm
Not many carnivals are centered around a dangerous blood disorder. But today’s Carnival for a Cause, hosted by East Carolina University, is as much about health education as it is about family fun. Th... […]
- Richmond organizations push for sickle cell awareness, donor registration on October 5, 2018 at 3:04 am
RICHMOND, VA (WWBT) - Several local groups are coming together to raise awareness and save the lives of those affected by sickle cell disease. Thousands of Americans have sickle cell disease, most of ... […]
- When to Get Tested for Sickle Cell Trait on October 4, 2018 at 4:44 pm
This is so important so listen up. Everybody knows that sickle cell disease is a blood disorder caused by abnormal hemoglobin, which is the oxygen-carrying protein that is found in red blood cells. Si... […]
- New Developments in Cure for Sickle Cell Disease from NIH on October 4, 2018 at 7:35 am
The National Institutes of Health (NIH) announced, Sept. 13, the launch of an initiative to speed up the development of a better cure for sickle cell disease. NIH is the nation’s medical research agen... […]
- GBT Announces Upcoming Presentations at National Sickle Cell Disease Association of America (SCDAA) Convention on October 4, 2018 at 5:00 am
SCD is a lifelong inherited blood disorder caused by a genetic mutation in the beta-chain of hemoglobin, which leads to the formation of abnormal hemoglobin known as sickle hemoglobin (HbS). […]
- Bridgeport FD raised nearly $10K for Sickle Cell research on October 3, 2018 at 9:27 pm
BRIDGEPORT — The city’s fire department raised nearly $10,000 to donate to research about Sickle Cell Disease. The fire department raised money during boot drives on Sept. 15 and Sept. 22. Firefighter... […]
- Sickle Cell in the ED: Old Therapies, New Strategies on October 2, 2018 at 11:39 am
SAN DIEGO -- Sickle cell disease stands out in the emergency room, and not just because patients with the condition often seek care again and again. It's also one of the few conditions whose treatment ... […]
- Danette Mitchell: Launch of ‘Cure Sickle Cell Initiative’ is long-awaited on September 30, 2018 at 8:26 am
... in a recent press release the launch of a new “Cure Sickle Cell Initiative” to help accelerate cures for sickle cell disease. The goal of the Initiative is to advance the development of the latest ... […]
- September is Sickle Cell Awareness Month on September 29, 2018 at 6:46 am
September marks Sickle Cell Awareness Month in the United States. Sickle cell disease is a potentially devastating illness, which affects primarily, though not exclusively, people with African heritag... […]
via Google News and Bing News