Stem Cells Repair Heart Attack Damage

(WebMD)  Can stem cells safely repair heart attack damage? Yes, a clinical trial suggests.

Bone marrow stem cells are supposed to home in on damaged parts of the heart. Once there, they send out signals that help the body repair the injury. There's also evidence, from animal studies, that the stem cells themselves engraft to the heart and help repopulate dead cells with new, living cells.

Now there's evidence from actual patients who suffered heart attacks. It comes from a study led by cardiologist Joshua M. Hare, director of the stem cell institute at the University of Miami Miller School of Medicine, and colleagues at nine other medical centers.

"Stem cell-treated patients had ... significant improvements in heart, lung, and global function," Hare said in a news release. "Echocardiography showed improved heart function, particularly in those patients with large amounts of cardiac damage."

It's not the first time heart attack patients have been treated with stem cells. But previous studies used bone marrow cells extracted from the patient and then injected directly into the heart.

Hare's team used an "off-the-shelf" stem cell product -- Prochymal -- containing stem cells harvested from a single healthy donor and grown to large numbers in laboratories. Prochymal is given by intravenous infusion. It's made by Osiris Therapeutics Inc., which sponsored the study, and which currently seeks FDA approval of the product as a treatment for graft-versus-host disease in transplant recipients.

"Many have argued that it's premature to test stem cells in patients," Hare said. "This trial ... lays the foundation for a brand new cell-based therapy for the human heart."

The Hare study enrolled 53 heart attack patients treated within 10 days of their first heart attack. None of the patients required bypass. A fourth of the patients got infusions of an inactive placebo; the others got various doses of the Prochymal cells.

The main goal of the study was to see if Prochymal was safe. It had been feared that the cells might cause growth of unwanted tissue in the arteries or the lungs. This did not happen. Patients receiving the stem cells had fewer adverse events than those who received placebo.

The secondary goal of the study was to gather some evidence that the treatment actually helped. There was such evidence -- particularly in the patients with the largest infarcts (patches of heart tissue killed during a heart attack).

Why? Emergency signals sent out by wounded heart tissue attract help from stem cells. It's probable that the stronger signal from the more damaged hearts attracted more of the stem cells to the site of injury, suggest Cleveland Clinic researchers Marc S. Penn, MD, PhD, and colleagues in an editorial accompanying the Hare report in the Dec. 8 issue of the Journal of the American College of Cardiology.

Warning that the Hare study is only a first step, Penn and colleagues call the findings "important."
"Many questions remain, but there is excitement in what the future holds with regard to advances in this field," they write.

A phase 2 clinical trial, also sponsored by Osiris, is enrolling heart attack patients.
By Daniel J. DeNoon
Reviewed by Louise Chang
©2005-2008 WebMD, LLC. All rights reserved

[porcine_aviator]

Note to everyone debating the merits of Human Embryonic Stem Cells (hESCs):

A) This study used stem cells from the bone marrow of an adult volunteer donor. No ESCs were used. At all. So you're debating a moot point regarding this study at least.

B) While it is debatable which is the lesser of two evils (flush the unused embryos away vs. blurr the lines of medical ethics), adult induced pluripotent stem cells (iPSCs) do not present such an ethical dilemma.

C) The totipotency gap is rapidly falling. Thus, in pretty short order, there will be fews reasons to prefer hESC over iPS cells.

D) With iPS cells, the phenotype of the cell is known in advance. Thus, the risk of graft-host disease of therapeutics can be eliminated with iPS cells.

E) There are ethical ways of harvesting hESCs, such as cord blood and placenta, and I wish more effort was being given to that rather than further enriching the "mommy in a bottle" clinics.

[krustykanuck]

Hey ToolMangler1: Embryonic Stem Cells were not banned from research during the Bush years, it was the Federal funding was banned for use with Embryonic stem cell reasearch. If you wish to support this use you own funds for donations. I for one do not wish my taxes to support the destruction of embryonic eggs. I would rather my taxes support other types of stem cell therapies thank you. Research has been effective with stem cells from the Placenta and other sources, in fact embryonic-like stem cells have even been derived from the Placenta. Your comments are nothing but a joke...

[rf35]

So I take it you would prefer the unused cells left over after in vitro fertilization to be flushed down the toilet instead of used in a way that could benefit mankind? Attitudes like that are the reason the Republicans were voted out.

[inketolstoy]

Great arguement rf35. You probably agree then with the Chinese selling the organs of political dissidents that they shot. No point in wasting perfectly good organs. And then there were those clever Nazis who didn't waste all those dead Holocaust victims by burning all of them. Get the gold teath. Attitudes like this are why liberals are losing their reputation for being for compassion and freedom.

[SusanStoHelit]

This is amazing - results so fast. And if they're drawn to damaged tissue, this could be an incredible treatment for all kinds of injury!

[us_1776]

This is really great news. I'd like to see a lot more research on this stem-cell method of healing the cardiovascular system.

Looked at what we've been missing during the Dark Ages of Bush/Cheney. Stem-cells are the key to the future of healing.

[inketolstoy]

Read your science genius. Bush Cheney only prohibited embryonic stem cell research (harvested from unborn children) not other types of stem cell research like cord blood or bone marrow stem cells. The only stem cell research that has been effective are the last two. No breakthroughs have come from the use of embryonic stem cell research. Maybe you think the current government should invest in alchemy, it is just as effective as embryonic stem cell research.

[doctor_know]

Regardless, the Bush/Cheney administration was terrible for the sicneces - the worst in history! As I scientist myself, I am thrilled that the republican party is no longer in control.

[chi-11]

No need to make this therapy available to the obstructionists who are so opposed to stem cell research.

Save it for the believers.