Monthly Archives: April 2013

Adult Stem Cells Isolated from Human Intestinal Tissue

Scientists at the University of North Carolina at Chapel Hill (UNC) report that for the first time adult stem cells from human intestinal tissue have been isolated. The accomplishment provides a much-needed resource for scientists eager to uncover the true mechanisms of human stem cell biology, they say. It also enables researchers to explore new tactics to treat inflammatory bowel disease or to ameliorate the side effects of chemotherapy and radiation, which often damage the gut. Stemcells blue

“Not having these cells to study has been a significant roadblock to research,” explained senior study author Scott T. Magness, Ph.D., assistant professor in the departments of medicine, biomedical engineering, and cell and molecular physiology at UNC. “Until now, we have not had the technology to isolate and study these stem cells. Now we have to tools to start solving many of these problems.”

The UNC study, published online in Stem Cells, represents a leap forward for a field that for many years has had to resort to conducting experiments in cells from mice, added Dr. Magness. While significant progress has been made using mouse models, differences in stem cell biology between mice and humans have kept researchers from investigating new therapeutics for human afflictions.

“While the information we get from mice is good foundational mechanistic data to explain how this tissue works, there are some opportunities that we might not be able to pursue until we do similar experiments with human tissue,” noted lead study co-author Adam D. Gracz, a graduate student in Dr. Magness’ lab.

The Magness lab was the first in the U.S. to isolate and grow single intestinal stem cells from mice, so they had a leg up when it came to pursuing similar techniques in human tissue. Plus the researchers were able to get sections of human small intestine for their experiments that otherwise would have been discarded after gastric bypass surgery at UNC.

To develop their technique, the researchers investigated whether the approach they had taken in mice would work in human tissue. They first looked to see if the same molecules they had found stuck on the surface of mouse stem cells were also present on human stem cells. The researchers established that these specific molecules (called CD24 and CD44) were indeed the same between the two species. They then attached fluorescent tags to these molecules and used a special machine called a fluorescence activated cell sorter to identify and isolate the stem cells from the small intestine samples.

They found that not only could they isolate the human stem cells from human intestinal tissue, but that they also could separate different types of intestinal stem cells from each other. These two types of stem cells, active and reserve, are a hot topic for stem cell researchers who are still trying to figure out how reserve stem cells cycle in to replenish active stem cells damaged by injury, chemotherapy, or radiation.

“Now that we have been able to do this, the next step is to carefully characterize these populations to assess their potential,” said Dr. Magness. “Can we expand these cells outside of the body to potentially provide a cell source for therapy? Can we use these for tissue engineering? Or to take it to the extreme, can we genetically modify these cells to cure inborn genetic disorders or inflammatory bowel disease? Those are some questions that we are going to explore in the future.”

 

Source: GENNewsHighlights, genengnews.com

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Myo Study: ‘Smart’ stem cells help heart failure patients

cardiac Treating heart failure patients with a special type of stem cell can improve their condition, according to a new Mayo Clinic study published this week.

The researchers used proteins to instruct the stem cells to behave like heart cells. All of the 45 patients in the clinical trial who received the “smart” stem cells saw more improvements in heart health than another group of patients who were given the standard treatments for heart failure.

The stem cell group’s hearts were able to pump more robustly and the patients showed improvements in physical fitness, such as being able to walk longer distances than the patients who didn’t receive the cells.

Dr. Andre Terzic, who led the research and is director of Mayo’s Center for Regenerative Medicine, said it is the first published study in which smart stem cells were tested on humans.

“I think it’s an exciting time where regenerative medicine is no longer science fiction but it’s increasingly becoming considered as a viable option for our patients, in particular the patients [who] have many unmet needs that current therapies cannot address,” Terzic said.

Terzic said the treatment will be tested on a group of 300 patients before researchers ask federal regulators to approve it, but he said he is hopeful because there were no patients in the current study who saw negative results. The study is published in the Journal of the American College of Cardiology.

Terzic said he also thinks the concept can be applied to other conditions.

“It will be, for example, fantastic to see cells instructed to be more neuron-like, to maybe go after some of the neurological disorders, or to be more bone-like to help an orthopedic surgery and so on,” he said.

Mayo disclosed that Terzic and the clinic have a financial interest related to technology in the research program. Mayo has rights to future royalties from Cardio3 BioSciences, a Belgium-based biotechnology company working on regenerative therapies for cardiovascular diseases.

 

Source: Elizabeth Dunbar, Minnesota Public Radio


Stem cells from fat may target brain cancer

Before you pack away the pounds in time for bikini weather, you might want to take a moment to thank your fat, for it may someday save your life. A new study found that stem cells derived from fat can be just as effective as stem cells derived from bone marrow in targeting and destroying cancer cells. And it’s not just any cancer, but the most common and aggressive human brain tumor — glioblastoma. fat-stem-cells

Glioblastoma is most feared for its ability to disperse cancer cells to remote areas of the brain, away from the central tumor. It can be resistant to the most common types of cancer treatment: surgical resection, radiation and chemotherapy. When the cancer cells migrate, they can create nests that are too small to detect but deadly enough to kill.

Alfredo Quinones-Hinojosa, a professor at the Hopkins School of Medicine and a director and neurosurgeon at Hopkins Bayview Hospital, leads the Brain Tumor Stem Cell Laboratory at Hopkins Hospital. Earlier this March, Quinones and his team of researchers released a new study in which they investigated the potential of stem cells from patients’ own fat to fight migrating cancer cells.

“Every patient has a little fat somewhere,” Quinones said. “And this is exciting, why? Because we never think of fat as anything other than bad.”

Stem cells can track migrating cancer cells and are used to deliver treatment therapies directly to them. Scientists commonly use stem cells taken from bone marrow, but commercial bone marrow stem cells are difficult to extract, making it a dangerous process.

Taking stem cells from adipose tissue, or fat, is typically easier and safer. The process is less invasive and expensive than the process of extracting stem cells from bone marrow. There is also evidence that stem cells from fat are more resistant to malignant transformations that can occur in transplanted stem cells.

This new study doesn’t just explore the possibility of using stem cells from fat, but from fat taken from the patients themselves. Doctors like Quinones can be excited for possibility of moving beyond one-size-fits-all treatments for brain cancer.

“There is no shotgun approach for any given disease,” Quinones said. “[But typically] we use one treatment for everybody.”

In addition to targeting cancer, stem cells from fat may also help in the treatment of neurodegenerative diseases.

Instead, this new approach of using the patients’ own fat cells could signal a future in personalized medicine where treatments are tailored to the patient, not just to the disease.

“You can treat [patients] as individuals rather than a whole group of people,” Quinones said.

Though a new solution to defeating glioblastoma is a huge breakthrough in itself, fat-derived stem cells hold the possibilities for so much more. Quinones explained that these stem cells have the ability to fight any kind of cancer, as well as neurodegenerative diseases, trauma injuries or damage from stroke.

“You have to be careful, you cannot oversell it,” Quinones said. “On the other hand… if you’re not excited about your own work no one else can get excited about it either.”

 

Source: Megan Jang, The Johns Hopkins News-Letter