New source of stem cells form heart muscle cells, repair damage

May 28, 2010, American Heart Association

A new and non-controversial source of stem cells can form heart muscle cells and help repair heart damage, according to results of preliminary lab tests reported in Circulation Research: Journal of the American Heart Association.

Investigators in Japan used the amniotic membrane — the inner lining of the sac in which an embryo develops — to obtain called human amniotic membrane-derived mesenchymal (undifferentiated) cells (hAMCs).

"The amniotic membrane is medical waste that could be collected and used after delivery," said Shunichiro Miyoshi, M.D., Ph.D., co-author of the study and assistant professor in the cardiology department and Institute for Advanced Cardiac Therapeutics at the Keio University School of Medicine in Tokyo.
In laboratory studies, the hAMCs:

  • transformed into , with 33 percent beating spontaneously.
  • improved function of rat hearts 34 percent to 39 percent when injected two weeks after a heart attack, while untreated hearts continued to decline in function.
  • decreased the scarred area of damaged rat hearts 13 percent to 18 percent when injected after a heart attack.
  • survived for more than four weeks in the rat heart without being rejected by the recipient's immune system, even without immunosuppressive medication.
The ability of hAMCs to convert into heart muscle cells was far greater than that from mesenchymal cells derived from bone marrow or fat, Miyoshi said.

That the implanted cells were not rejected is likely because the amniotic sac is a barrier between a woman and her developing fetus. To help prevent either of their immune systems from attacking the other as foreign tissue, the amniotic membrane between them does not produce the proteins that immune systems use to identify foreign tissue. This means the usual tissue-type matching (HLA typing) needed prior to transplantation would not be needed if hAMCs were used. Drugs to suppress the immune system also might not be needed after transplant.

The findings also suggest that hAMCs can differentiate into cells of various organs.

"If we had to create a cell bank system to cover every HLA type, we would need to store a great amount of cells, many of which would never be used," Miyoshi said. "Because hAMCs do not require such a system, it would be less expensive and usable for all patients."

Much work remains to be done before testing hAMCs in humans, said the researchers, who are repeating their experiments in larger animals and working to boost the number of heart cells generated by the hAMCs.

The investigators "are to be congratulated for their careful work that has brought forward a cell type that may offer the real potential for off-the-shelf cardiac myocyte [muscle cell]-based therapy," Marc S. Penn, M.D., Ph.D., and Maritza E. Mayorga, Ph.D., of the Cleveland Clinic, wrote in an editorial in Circulation Research.

Related Stories

Recommended for you

Researchers devise decoy molecule to block pain where it starts

January 16, 2018
For anyone who has accidentally injured themselves, Dr. Zachary Campbell not only sympathizes, he's developing new ways to blunt pain.

Scientists unleash power of genetic data to identify disease risk

January 16, 2018
Massive banks of genetic information are being harnessed to shed new light on modifiable health risks that underlie common diseases.

Blood-vessel-on-a-chip provides insight into new anti-inflammatory drug candidate

January 15, 2018
One of the most important and fraught processes in the human body is inflammation. Inflammatory responses to injury or disease are crucial for recruiting the immune system to help the body heal, but inflammation can also ...

Molecule produced by fat cells reduces obesity and diabetes in mice

January 15, 2018
UC San Francisco researchers have discovered a new biological pathway in fat cells that could explain why some people with obesity are at high risk for metabolic diseases such as type 2 diabetes. The new findings—demonstrated ...

Obese fat becomes inflamed and scarred, which may make weight loss harder

January 12, 2018
The fat of obese people becomes distressed, scarred and inflamed, which can make weight loss more difficult, research at the University of Exeter has found.

Optimized human peptide found to be an effective antibacterial agent

January 11, 2018
A team of researchers in the Netherlands has developed an effective antibacterial ointment based on an optimized human peptide. In their paper published in the journal Science Translational Medicine, the group describes developing ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

BrianH
not rated yet May 28, 2010
It's also interesting that there are now suggestions the umbilical cord should be left functional a lot longer after birth to facilitate transport and migration of stem cells from the placenta into the newborn. It has long-term protective effects.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.