Featured Research

from universities, journals, and other organizations

Better tissue healing with disappearing hydrogels

Date:
June 6, 2014
Source:
University of Rochester
Summary:
When stem cells are used to regenerate bone tissue, many wind up migrating away from the repair site, which disrupts the healing process. But a research team makes use of a technique that keeps the stem cells in place, resulting in faster and better tissue regeneration.

This is a representation of hydrogel polymers (straight lines) trapping stem cells (light-colored figures) and water (blue).
Credit: Graphic by Michael Osadciw/University of Rochester.

When stem cells are used to regenerate bone tissue, many wind up migrating away from the repair site, which disrupts the healing process. But a technique employed by a University of Rochester research team keeps the stem cells in place, resulting in faster and better tissue regeneration. The key, as explained in a paper published in Acta Biomaterialia, is encasing the stem cells in polymers that attract water and disappear when their work is done.

Related Articles


The technique is similar to what has already been used to repair other types of tissue, including cartilage, but had never been tried on bone.

"Our success opens the door for many -- and more complicated -- types of bone repair," said Assistant Professor of Biomedical Engineering Danielle Benoit. "For example, we should now be able to pinpoint repairs within the periosteum -- or outer membrane of bone material."

The polymers used by Benoit and her teams are called hydrogels because they hold water, which is necessary to keep the stem cells alive. The hydrogels, which mimic the natural tissues of the body, are specially designed to have an additional feature that's vital to the repair process; they degrade and disappear before the body interprets them as foreign bodies and begins a defense response that could compromise the healing process.

Because stem cells have the unique ability to develop into many different types of cells, they are an important part of the mechanism for repairing body tissue. At present, unadulterated therapeutic stem cells are injected into the bone tissue that needs to be repaired. Benoit believed hydrogels would allow the stem cells to finish the job of initiating repairs, then leave before overstaying their welcome.

The research team tested the hypothesis by transplanting cells onto the surface of mouse bone grafts and studying the cell behavior both in vivo -- inside the animal -- and in vitro -- outside the body. They started by removing all living cells from donor bone fragments, so that the tissue regeneration could be accomplished only by the stem cells.

In order to track the progress of the research, the stem cells were genetically modified to include genes that give off fluorescence signals. The bone material was then coated with the hydrogels, which contained the fluorescently labeled stem cells, and implanted into the defect of the damaged mouse bone. At that point, the researchers began monitoring the repair process with longitudinal fluorescence to determine if there would be an appreciable loss of stem cells in the in vivo samples, as compared to the static, in vitro, environments. They found that there was no measurable difference between the concentrations of stem cells in the various samples, despite the fact that the in vivo sample was part of a dynamic environment -- which included enzymes and blood flow -- making it easier for the stem cells to migrate away from the target site. That means virtually all the stem cells stayed in place to complete their work in generating new bone tissue.

"Some types of tissue repair take more time to heal than do others," said Benoit. "What we needed was a way to control how long the hydrogels remained at the site."

Benoit and her team were able to manipulate the time it took for hydrogels to dissolve by modifying groups of atoms -- called degradable groups -- within the polymer molecules. By introducing different degradable groups to the polymer chains, the researchers were able to alter how long it took for the hydrogels to degrade.

Benoit believes degradable hydrogels show promise in many research areas. For example, it may be possible to initiate tissue regeneration after heart attacks without having a patient undergo difficult, invasive surgery, but a great deal of additional research is required.


Story Source:

The above story is based on materials provided by University of Rochester. Note: Materials may be edited for content and length.


Journal Reference:

  1. Michael D. Hoffman, Amy H. Van Hove, Danielle S.W. Benoit. Degradable hydrogels for spatiotemporal control of mesenchymal stem cells localized at decellularized bone allografts. Acta Biomaterialia, 2014; DOI: 10.1016/j.actbio.2014.04.012

Cite This Page:

University of Rochester. "Better tissue healing with disappearing hydrogels." ScienceDaily. ScienceDaily, 6 June 2014. <www.sciencedaily.com/releases/2014/06/140606184921.htm>.
University of Rochester. (2014, June 6). Better tissue healing with disappearing hydrogels. ScienceDaily. Retrieved December 19, 2014 from www.sciencedaily.com/releases/2014/06/140606184921.htm
University of Rochester. "Better tissue healing with disappearing hydrogels." ScienceDaily. www.sciencedaily.com/releases/2014/06/140606184921.htm (accessed December 19, 2014).

Share This


More From ScienceDaily



More Health & Medicine News

Friday, December 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

The Best Tips to Curb Holiday Carbs

The Best Tips to Curb Holiday Carbs

Buzz60 (Dec. 19, 2014) It's hard to resist those delicious but fattening carbs we all crave during the winter months, but there are some ways to stay satisfied without consuming the extra calories. Vanessa Freeman (@VanessaFreeTV) has the details. Video provided by Buzz60
Powered by NewsLook.com
Sierra Leone Bikers Spread the Message to Fight Ebola

Sierra Leone Bikers Spread the Message to Fight Ebola

AFP (Dec. 19, 2014) More than 100 motorcyclists hit the road to spread awareness messages about Ebola. Nearly 7,000 people have now died from the virus, almost all of them in west Africa, according to the World Health Organization. Video provided by AFP
Powered by NewsLook.com
Researchers Test Colombian Village With High Alzheimer's Rates

Researchers Test Colombian Village With High Alzheimer's Rates

AFP (Dec. 19, 2014) In Yarumal, a village in N. Colombia, Alzheimer's has ravaged a disproportionately large number of families. A genetic "curse" that may pave the way for research on how to treat the disease that claims a new victim every four seconds. Duration: 02:42 Video provided by AFP
Powered by NewsLook.com
Kids Die While Under Protective Services

Kids Die While Under Protective Services

AP (Dec. 18, 2014) As part of a six-month investigation of child maltreatment deaths, the AP found that hundreds of deaths from horrific abuse and neglect could have been prevented. AP's Haven Daley reports. (Dec. 18) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins