(Press-News.org) WASHINGTON, DC—Researchers at the University of Michigan Department of Surgery have begun testing an alternative to embryonic stem cells that could one day regenerate muscle tissue for babies with congenital heart defects. A research-in-progress report on this new approach, which uses amniotic stem cells, was presented today at the 2013 Clinical Congress of the American College of Surgeons. Although this research is still in an early phase, this new approach has the potential to one day help thousands of babies born each year with congenital heart defects.
Typically, a pregnant woman can have a fetal ultrasound performed to find out the sex of her baby between 18 and 20 weeks gestation. But each year during pregnancy or after birth, 40,000 women also find out that their babies have birth defects in their hearts, according to the Centers for Disease Control and Prevention.*
Babies with congenital heart defects often go through multiple heart operations or even a transplant before their first birthday. But Shaun Kunisaki, MD, a pediatric surgeon and assistant professor of surgery at the University of Michigan, and his surgical team are testing a new method of regenerating defective heart tissue so that one day these multiple operations may no longer be necessary.
"We know that the baby's heart cells are functioning, but the muscle has developed abnormally," lead study author Dr. Kunisaki said. "We have to find the right source of new cells to replace the damaged cells or generate new tissue to augment the damaged heart."
Stem Cell Shortfalls
Until now embryonic stem cells have shown potential to morph into various types of organ tissues, but the ethics surrounding the process of having to destroy the embryo to achieve this outcome has drawn controversy.
Stem cells from bone marrow have also seemed promising, but such cells are obviously hard to obtain from a fetus. Furthermore, getting bone marrow from a donor brings about the same risk as having a heart transplant—having to suppress the newborn infant's immune system so that its body doesn't reject the foreign cells. "Also, bone marrow cells are not made to function like heart muscle cells, but rather to protect against inflammation," Dr. Kunisaki explained.
Cardiac stem cells, which are in the heart, have also been considered, but the heart contains a very limited number of these stem cells.
Amniotic stem cells, however, contain the same genetic makeup as the fetus. Therefore, this approach eliminates the possibility of the newborn infant's body rejecting the cells. And these cells are easily obtainable from amniocentesis, a standard prenatal genetic test in which fluid is extracted from the amniotic sac.
Morphing into heart muscle cells
Beginning in the last quarter of 2011, Dr. Kunisaki and his team obtained amniotic fluid samples from eight pregnant women. They extracted a type of cell called mesenchymal stromal cells, which are the most common type of cell in amniotic fluid.
The next step was to transform those cells into induced pluripotent stem cells with the exact genetic makeup of the fetus. This step involved genetically reprogramming the cells to be, similar to embryonic stem cells, flexible enough to morph into any cell in the human body—such as the heart muscle.
"Once you have true stem cells, then you can expose these cells in a culture condition, which favors transformation into a heart cell," Dr. Kunisaki reported.
After three weeks in a culture, Dr. Kunisaki and his team observed the amniotic stem cells transform into heart muscle cells. The team confirmed that the cells were indeed heart cells with an antibody test, which has signature proteins that only bind to certain types of cells—in this case, the newly grown heart cells. "And you could see these cells beating in the culture dish," he added.
Next steps and ultimate goals
In the future, Dr. Kunisaki envisions being able to deliver amniotic stem cells to babies with congenital heart defects soon after delivery. The cells would then begin to regenerate damaged tissue into a healthy heart or could serve to augment heart operations. This treatment could help newborn infants stay alive without a transplant.
"Babies have to rely on mom and the placenta for everything. After they're born, they have to rely on their own hearts to function," Dr. Kunisaki explained. "The ideal situation is to have heart stem cells available when they are born. We diagnose heart defects at about 20 weeks gestation. That timeframe gives five months or so to generate heart cells to use at birth."
The researchers' laboratory process of transforming amniotic fluid cells into beating heart cells took just under 12 weeks. The next step is to move the study to a mouse model, which Dr. Kunisaki estimates will begin in 2014. The ultimate step will be testing the procedure on an actual baby.
"Pregnancy is supposed to be a time to celebrate and welcome a new family member into the world. One of the hardest parts of my job as a surgeon is telling a family that their baby has a heart defect," Dr. Kunisaki said. "Instead, these families have to talk about unforeseen circumstances, such as how to care for a seriously ill child after birth. Often there are not many comforting answers, but our goal is to offer more options."
INFORMATION:
Guihua Jian, MS; Julie DiBernardo, PhD; Luis G. Villa-Diza, PhD, DVM; Paul H. Krebsbach, PhD; and K. Sue O'Shea, PhD, also participated in the study.
* Centers for Disease Control and Prevention. Congenital Heart Defects – Data and Statistics. Available at: http://www.cdc.gov/ncbddd/heartdefects/data.html. Accessed September 6, 2013.
END
(OCTOBER 9, 2013)— The deadly cholera epidemic that rocked earthquake-shattered Haiti in 2010, claiming 8,000 lives and counting, has rallied the public health community to seek water and sewer improvements that, combined with vaccination, could prevent some 89,000 future cholera infections. These findings are among the many insights published this month in a special section of the American Journal of Tropical Medicine and Hygiene - AJTMH and PAHO: Commemorating the 3rd Anniversary of the Cholera Outbreak in Haiti: Invited Papers documenting the public health response ...
Johns Hopkins researchers, working with elderly mice, have determined that combining gene therapy with an extra boost of the same stem cells the body already uses to repair itself leads to faster healing of burns and greater blood flow to the site of the wound.
Their findings offer insight into why older people with burns fail to heal as well as younger patients, and how to potentially harness the power of the body's own bone marrow stem cells to reverse this age-related discrepancy.
"As we get older, it is harder for our wounds to heal," says John W. Harmon, M.D., ...
Located about 1200 light-years from Earth in the southern constellation of Carina (The Ship's Keel), the Toby Jug Nebula, more formally known as IC 2220, is an example of a reflection nebula. It is a cloud of gas and dust illuminated from within by a star called HD 65750. This star, a type known as a red giant, has five times the mass of our Sun but it is in a much more advanced stage of its life, despite its comparatively young age of around 50 million years [1].
The nebula was created by the star, which is losing part of its mass out into the surrounding space, forming ...
Zudin A. Puthucheary, M.R.C.P., of University College London, England, and colleagues conducted a study to characterize and evaluate the time course and pathophysiology of acute muscle loss in critical illness.
"Survivors of critical illness experience significant skeletal muscle weakness and physical disability, which can persist for at least 5 years. Muscle wasting contributes substantially to weakness acquired in the intensive care unit, but its time course and underlying pathophysiological mechanisms remain poorly characterized and not well understood," according ...
Laurent Papazian, M.D., Ph.D., of Hôpital Nord, Marseille, France, and colleagues conducted a study to determine whether statin therapy decreased day-28 mortality among intensive care unit patients with ventilator-associated pneumonia.
Observational studies have reported that statins improve outcomes of various infections. Ventilator-associated pneumonia (VAP) is the most common infection in the intensive care unit (ICU) and is diagnosed in approximately 8 to 28 percent of ICU patients receiving mechanical ventilation. Ventilator-associated pneumonia is associated with ...
Djillali Annane, M.D., Ph.D., of Raymond Poincare Hospital, Garches, France, and colleagues conducted a study to compare the effects of 2 types of intravenous fluids on survival for critically ill patients in an intensive care unit.
Thousands of patients in intensive care units (ICUs) throughout the world are treated every day with intravenous fluids, mainly to restore effective blood volume and perfusion of organs. Fluid therapy includes a broad variety of products that are categorized as crystalloids and colloids: crystalloids are salts; colloids are salts and gelatin, ...
Andrea Morelli, M.D., of the University of Rome, Italy, and colleagues conducted a study to investigate the effect of the short-acting beta-blocker esmolol on the heart rate of patients with severe septic shock and high risk of death.
Septic shock is associated with adverse effects on cardiac function. Beta-blocker therapy controls heart rate and may improve cardiovascular performance, but concerns remain that this therapy may lead to cardiovascular decompensation (inability of the heart to maintain adequate circulation), according to background information in the article. ...
Researchers working at the University of Saskatchewan have discovered new potential in prairie fruits, in particular, buffaloberry, chokecherry and sea buckthorn, according to a new study published today in the Canadian Journal of Plant Science. Findings showed that these fruits were nutrient-rich and that the potential food value is high. This is good news for fruit growers in Saskatchewan as these results add further credence to support the development of these fruits for commercial food markets.
"There is increasing interest in the commercial development of these ...
The German Institute for Quality and Efficiency in Health Care (IQWiG) analysed additional data on drugs from the group of gliptins. The drug manufacturers had subsequently submitted these data to the Federal Joint Committee (G-BA) in the commenting procedure. The Institute came to a different conclusion on the fixed combination of sitagliptin/metformin: As for the single agent sitagliptin before, there are now hints of an added benefit for this fixed combination. However, IQWiG still does not see any advantages of vildagliptin and the fixed combination of vildagliptin ...
New York University chemists have discovered crystal growth complexities, which at first glance appeared to confound 50 years of theory and deepened the mystery of how organic crystals form. But, appearances can be deceiving.
Their findings, which appear in the latest edition of Proceedings of the National Academy of Sciences, have a range of implications -- from the production of pharmaceuticals and new electronic materials to unraveling the pathways for kidney stone formation.
The researchers focused on L-cystine crystals, the chief component of a particularly nefarious ...
