 |
|
Researchers grow human blood vessels in mice from adult progenitor cells
July 21, 2008For the first time, researchers have successfully grown functional human blood vessels in mice using cells from adult human donors - an important step in developing clinical strategies to grow tissue, researchers report in Circulation Research: Journal of the American Heart Association.
"What's really significant about our study is that we are using human cells that can be obtained from blood or bone marrow rather than removing and using fully developed blood vessels," said Joyce Bischoff, Ph.D., senior author of the study and associate professor at Harvard Medical School and Children's Hospital Boston.
The researchers combined two different types of progenitor cells in a culture dish of nutrients and growth factors, then washed off the nutrients and implanted the cells into mice with weakened immune systems. Once implanted, the progenitor cell mixture grew and differentiated into a small ball of healthy blood vessels.
Progenitor cells are similar to stem cells but can only differentiate into specific cells, while stem cells can differentiate into practically any cell in the body.
In the study, researchers used two different kinds of progenitor cells to grow blood vessels: the endothelial progenitor cells (EPCs), which become cells that line the vessels, and mesenchymal progenitor cells (MPCs), which differentiate into the cells that surround the lining and provide stability.
The researchers used different combinations of the two types of progenitor cells. They found that a mixture of adult blood- and adult bone marrow-derived progenitor cells or a combination of umbilical cord blood-derived and adult bone marrow-derived cells resulted in the greatest density of new blood vessel formation.
The ability to rapidly grow two-layered blood vessels without using embryonic or umbilical cord blood stem cells could skirt many ethical concerns, Bischoff said. It would also solve a persistent problem in treating several medical conditions that result from ischemia - the inability of oxygen-rich blood to reach an organ or tissue - such as heart attacks, wound healing and many acute injuries.
"What we are most interested in right now is speeding up the vascularization (the formation of blood vessels)," Bischoff said. "We see very good and extensive vasculature in seven days and we'd like to see that in 24 or 48 hours. If you have an ischemic tissue, it's dying tissue, so the faster you can establish blood flow the better."
If researchers can develop ways to speed the growth of the vessels, non-surgical cardiac bypass procedures could potentially grow new vessels around those blocked by atherosclerosis.
Bischoff said other findings include:
• The cells created a vigorous network of vessels that connected to one another and to the vessels of the host mouse within seven days and continued to transport blood during the four-week study.
• Once combined and implanted, the two progenitor cells arranged themselves into vessels with minimal outside help, i.e., without any genetic alteration or manipulation to improve their growth. This is important because many growth-promoting genes are the same genes that become activated in cancer.
• Mixtures of EPCs and MPCs from adult donors were as effective at generating vessels as those made from a mixture of cord blood EPCs and adult bone marrow MPCs. That finding increases the likelihood of someday being able to easily find clinically useful amounts of progenitor cells.
The research could also enhance tissue engineering - growing new organs for later implantation into patients, another medical research field that needs good sources of microvascularization to develop, Bischoff said.
Co-authors are Juan M. Melero-Martin, Ph.D., lead author; Maria E. De Obaldia, A.B.; Soo-Young Kang, Ph.D.; Zia A. Khan, Ph.D.; Lei Yuan, Ph.D.; and Peter Oettgen, M.D. Individual author disclosures can be found on the manuscript.
The U.S. Army funded the research.
American Heart Association
Progenitor cells are similar to stem cells but can only differentiate into specific cells, while stem cells can differentiate into practically any cell in the body.
In the study, researchers used two different kinds of progenitor cells to grow blood vessels: the endothelial progenitor cells (EPCs), which become cells that line the vessels, and mesenchymal progenitor cells (MPCs), which differentiate into the cells that surround the lining and provide stability.
The researchers used different combinations of the two types of progenitor cells. They found that a mixture of adult blood- and adult bone marrow-derived progenitor cells or a combination of umbilical cord blood-derived and adult bone marrow-derived cells resulted in the greatest density of new blood vessel formation.
The ability to rapidly grow two-layered blood vessels without using embryonic or umbilical cord blood stem cells could skirt many ethical concerns, Bischoff said. It would also solve a persistent problem in treating several medical conditions that result from ischemia - the inability of oxygen-rich blood to reach an organ or tissue - such as heart attacks, wound healing and many acute injuries.
"What we are most interested in right now is speeding up the vascularization (the formation of blood vessels)," Bischoff said. "We see very good and extensive vasculature in seven days and we'd like to see that in 24 or 48 hours. If you have an ischemic tissue, it's dying tissue, so the faster you can establish blood flow the better."
If researchers can develop ways to speed the growth of the vessels, non-surgical cardiac bypass procedures could potentially grow new vessels around those blocked by atherosclerosis.
Bischoff said other findings include:
• The cells created a vigorous network of vessels that connected to one another and to the vessels of the host mouse within seven days and continued to transport blood during the four-week study.
• Once combined and implanted, the two progenitor cells arranged themselves into vessels with minimal outside help, i.e., without any genetic alteration or manipulation to improve their growth. This is important because many growth-promoting genes are the same genes that become activated in cancer.
• Mixtures of EPCs and MPCs from adult donors were as effective at generating vessels as those made from a mixture of cord blood EPCs and adult bone marrow MPCs. That finding increases the likelihood of someday being able to easily find clinically useful amounts of progenitor cells.
The research could also enhance tissue engineering - growing new organs for later implantation into patients, another medical research field that needs good sources of microvascularization to develop, Bischoff said.
Co-authors are Juan M. Melero-Martin, Ph.D., lead author; Maria E. De Obaldia, A.B.; Soo-Young Kang, Ph.D.; Zia A. Khan, Ph.D.; Lei Yuan, Ph.D.; and Peter Oettgen, M.D. Individual author disclosures can be found on the manuscript.
The U.S. Army funded the research.
American Heart Association
Progenitor Cells Current Events and Progenitor Cells News RSSNewly identified cells make fat
To understand where fat comes from, you have to start with a skinny mouse. By using such a creature, and observing the growth of fat after injections of different kinds of immature cells, scientists at the Howard Hughes Medical Institute and Rockefeller University have discovered an important fat precursor cell that may in time explain how changes in the numbers of fat cells might increase and lead to obesity.
Joslin study identifies protein that produces 'good' fat
A study by researchers at the Joslin Diabetes Center has shown that a protein known for its role in inducing bone growth can also help promote the development of brown fat, a "good" fat that helps in the expenditure of energy and plays a role in fighting obesity.
Sensitivity to antidepressants linked with TrkB-mediated neural proliferation
Scientists have unveiled a functional link between production of new neurons and the effectiveness of antidepressants (ADs) in an animal model. The study, published by Cell Press in the August 14 issue of the journal Neuron, provides exciting insight into a mechanism that might underlie a poor response to antidepressive medications for anxiety or depression.
Cancer cells with a long breath: seeking the origin of brain tumors in children
Medulloblastoma is one of the most common and most malignant brain tumours among children and teenagers. These tumours grow very rapidly, and fifty percent of patients in the long term die from the condition.
Childhood brain tumor traced to normal stem cells gone bad
An aggressive childhood brain tumor known as medulloblastoma originates in normal brain "stem" cells that turn malignant when acted on by a known mutant, cancer-causing oncogene, say researchers from Dana-Farber Cancer Institute and the University of California, San Francisco (UCSF).
Statins have unexpected effect on pool of powerful brain cells
Cholesterol-lowering drugs known as statins have a profound effect on an elite group of cells important to brain health as we age, scientists at the University of Rochester Medical Center have found. The new findings shed light on a long-debated potential role for statins in the area of dementia.
Nerve cells derived from stem cells and transplanted into mice may lead to improved brain treatments
Scientists at the Burnham Institute for Medical Research have, for the first time, genetically programmed embryonic stem (ES) cells to become nerve cells when transplanted into the brain, according to a study published today in The Journal of Neuroscience.
U of M Sets Course For Cure of Fatal Childhood Skin Disease
Physicians at the University of Minnesota and University of Minnesota Children's Hospital, Fairview have set the path to a cure for a young boy's fatal genetic skin disease, recessive dystrophic epidermolysis bullosa (RDEB), by using a cord blood and bone marrow transplant. Nate Liao, a 25-month-old from Clarksburg, N.J., underwent the experimental therapy in October 2007.
UCLA stem cell researchers create heart and blood cells from reprogrammed skin cells
Stem cell researchers at UCLA were able to grow functioning cardiac cells using mouse skin cells that had been reprogrammed into cells with the same unlimited properties as embryonic stem cells.
A stem cell type supposed to be crucial for angiogenesis and cancer growth does not exist?
Angiogenesis, the growth of new blood vessels, is a central process in diverse physiological and pathological situations such as healing of wounds and traumas, cardiovascular disorders, inflammatory conditions such as rheumatoid arthritis, and in cancer growth.
More Progenitor Cells Current Events and Progenitor Cells News Articles
| Hematopoietic Progenitor Cells: Processing, Standards and Practice | |
 | Standards for Hematopoietic Progenitor Cells |
| Standards for Hematopoietic Progenitor Cell Services by American Association of Blood Banks Standards developed on the basis of good medical practice and, when available, scientific data. They directly address hematopoietic progenitor cell processes and procedures, but can be applied to other cellular therapy interventions. Reflects new requirements, such as the full incorporation of a quality management system. Outline format. Previous edition: c1996. Three-hole... | |
 | Novel Angiogenic Mechanisms: Role of Circulating Progenitor Endothelial Cells (Advances in Experimental Medicine and Biology) This volume illustrates the current lines of investigation of the angiogenic mechanisms based on contribution of circulating progenitor cells. The main themes that currently dominate this research field are: the origin of these cells, their tissue engraftment, their phenotypic modulation leading to the transformation into endothelial cells, etc. This volume is a key reference for angiogenesis... |
| Neuroepithelial Stem Cells and Progenitors (Developmental Neuroscience, 1-2) | |
| StemCells receives United States patent for methods of isolating pancreatic progenitor cells.: An article from: BIOTECH Patent News This digital document is an article from BIOTECH Patent News, published by Biotech Patent News on April 1, 2003. The length of the article is 2236 words. The page length shown above is based on a typical 300-word page. The article is delivered in HTML format and is available in your Amazon.com Digital Locker immediately after purchase. You can view it with any web browser.Citation DetailsTitle:... | |
 | Stem and Progenitor Cells in the Central Nervous System: Developmental Neuroscience 2004 No. 2-4 by R. S. Nowakowski |
 | Isolation and Induction of Neuronal Progenitor Cells: Rostock Spring School 2006 Contributions, Special Issue, Neurodegenerative Diseases 2007 |
 | Hematopoietic Progenitor Cells: A Primer for Medical Professionals by Edward L. Snyder, N. Rebecca Haley Yale Univ., New Haven, CT. Pocket guide to the biology of HPCs, including the basic science of these cells and their function. Discusses concepts of the HLA system regarding recognition of self vs non-self. Provides information on regulations and standards for hematopoietic progenitor cell facilities and discusses professional standards. Previous edition: c1995.... |
| Identification and Characterization of Neural Progenitor Cells in the Adult Mammalian Brain (Advances in Anatomy, Embryology and Cell Biology) by Sara Gil-PerotĂn, Arturo Alvarez-Buylla, JosĂ© Manuel GarcĂa-Verdugo Adult neurogenesis has been questioned for many years. In the early 1900s, a dogma was established that denied new neuron formation in the adult brain. In the last century however, new discoveries have demonstrated the real existence of proliferation in the adult brain, and in the last decade, these studies led to the identification of neural stem cells in mammals. Adult neural stem cells are... |
| © 2008 BrightSurf.com |