The results of the trial, called Transplantation In Myocardial Infarction Evaluation (TIME), mirror a previous, related study, LateTIME, which found that such cells (called autologous stem cells) given two to three weeks after a heart attack did not improve heart function. Both TIME and LateTIME were conducted by the Cardiovascular Cell Therapy Research Network (CCTRN), sponsored by the NIH's National Heart, Lung, and Blood Institute.
The findings will be presented Tuesday, Nov. 6, at the American Heart Association (AHA) 2012 Scientific Sessions in Los Angeles and will appear concurrently in the Journal of the American Medical Association.
"This study was extremely valuable even though it did not provide a demonstrated health benefit after six months," said Sonia Skarlatos, Ph.D., deputy director of NHLBI's Division of Cardiovascular Sciences and member of the CCTRN. "Heart stem cell therapy research is still in its infancy, and results from early trials have varied greatly due to differences in the numbers of stem cells injected, the delivery methods used, and the compositions of the study populations. With TIME and LateTIME, we have established both safety and baseline results in two large studies that followed the same procedures for growing and then administering stem cells. This standard will inform the next steps in research on the use of stem cells to repair damaged hearts."
"With this baseline now set, we can start to adjust some of the components of the protocol to grow and administer stem cell to find cases where the procedure may improve function," added fellow CCTRN member Jay Travese, M.D., of the Minneapolis Heart Institute, who will present the results at the meeting. "For example, this therapy may work better in different population groups, or we might need to use new cell types or new methods of delivery."
Skarlatos noted that another advantage of the TIME study is that CCTRN is storing samples of the stem cells taken from the participants. Investigators can examine the relationship between people who showed significant improvement during the study and the characteristics of their stem cells. Such a comparison may offer insights on the cell traits that are associated with clinical improvement.
Between July 2008 and February 2011, TIME researchers enrolled 120 volunteers (average age 57, 87.5 percent male) who suffered from moderate to severe impairment in their left ventricles – the part of the heart that pumps oxygen-rich blood to the body – and had undergone stenting procedures following heart attacks. Those selected for the trial were assigned randomly to one of four groups: day three after heart attack stem cell injection, day three after heart attack placebo injection, day seven after heart attack stem cell treatment, or day seven after heart attack placebo treatment. The researchers developed a method of processing and purifying the stem cells to ensure that participants in the stem cell groups received a uniform dose of 150 million cells about 8 hours after the cells were harvested from their bone marrow. This ensured that results would not be skewed by differences in the quantity or quality of stem cells administered.
Researchers assessed heart improvement six months after stem cell therapy by measuring the percentage of blood that was pumped out of the left ventricle during each contraction (known as the left-ventricular ejection fraction, or LVEF). The study found no significant differences between the change in LVEF readings at the six-month follow-up in either the day three or the day seven stem cell groups compared with placebo groups or with each other. Every group showed about a three percent improvement in LVEF.
To schedule an interview with an NHLBI spokesperson, contact the NHLBI Office of Communications at 301-496-4236 or NHLBI_news@nhlbi.nih.gov.
Resources:What is a heart attack? http://www.nhlbi.nih.gov/health/health-topics/topics/heartattack/
NHLBI Communications | EurekAlert!
GLUT5 fluorescent probe fingerprints cancer cells
20.04.2018 | Michigan Technological University
Scientists re-create brain neurons to study obesity and personalize treatment
20.04.2018 | Cedars-Sinai Medical Center
University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.
Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.
Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.
Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...
Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.
The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...
Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.
Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...
In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...
13.04.2018 | Event News
12.04.2018 | Event News
09.04.2018 | Event News
20.04.2018 | Physics and Astronomy
20.04.2018 | Interdisciplinary Research
20.04.2018 | Physics and Astronomy