Better tissue healing with 'dissolving' hydrogels

Regenerating bone tissue through stem cells can now be easier and more precise.

Researchers at University of Rochester, New York, have developed a technique to keep the stem cells from moving away, resulting in faster and better tissue regeneration.

When stem cells are used to regenerate bone tissue, a number of them move away from the repair site that disrupts the healing process.

The new technique is encasing the stem cells in polymers that attract water and disappear when their work is done.

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 Danielle Benoit, an assistant professor of biomedical engineering at University of Rochester.

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 defence response that could compromise the healing process.

"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, she added.

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.

The findings were reported in Acta Biomaterialia.