How do you get stem cells to survive after they have been transplanted? You can pre-condition them, but research from Johns Hopkins University has capitalized on a different strategy. The Hopkins team used hydrogel to protect and feed the stem cells that had been implanted into the heart.
They utilized a rat model system for this work. Rats that had been given heart attacks were given stem cell implants encased in a hydrogel. The hydrogel supported stem cells survival and also kept the stem cells at the site of their implantation where they re-muscularized the damaged heart muscle. 73% of the stem cells embedded in hydrogel survived whereas only 12% of the non-hydrogel-embedded stem cells survived after injection into the heart.
Previously, stem cell injections have been shown to aid damaged heart tissue, but the vast majority of the injected cells die or are washed from the heart into other tissues. Hydrogel, which mostly consists of water, allows the cells to live and grow while they integrate into the surrounding tissue and initiate healing.
Heart-damaged rats injected with hydrogel-loaded stem cells saw a 15% increase in pumping efficiency for the treated ventricle, compared with just 8% for regular stem cell therapies. Hydrogen can support both adult and embryonic stem cells, and if it’s not put inside a living being, the hydrogel can actually maintain 100% of the stem cells embedded in them.
Hydrogels are useful in biology because they are safe for use in living organisms. In fact, this study found that injecting the hydrogel alone, with no stem cells at all, had a mild benefit all its own by promoting new blood vessel growth.
These are the sorts of breakthroughs that will allow the stem cell technologies of today to become the amazing stem cell technologies of tomorrow.