To prove the cells’ regenerative powers, bone cells grown on this surface were then placed into holes in the skulls of mice, resulting in four times as much new bone growth as in the mice without the extra bone cells.
Embryonic stem cells can become anything they want to be when they develop: organs, nerves, skin, bone, any type of human cell. Adult-derived stem cells can do this and better. Since the source cells come directly from the patient, they are perfectly compatible for medical treatments.
In order to make them, researchers turn human skin cells into stem cells. Less than five years following the discovery of this method, researchers are still trying to understand the exact workings of this process. However, it is known that it involves adding proteins that can turn genes on and off to the adult cells.
Before stem cells can be used to make repairs in the body, they must be developed and guided into becoming the desired cell type. Researchers typically use surfaces of animal cells and proteins for stem cell habitats, but these gels are expensive to make, and batches vary depending on the individual animal.
However, problems arise when human stem cells are grown over mouse cells. In some instances, the cells begin to produce some mouse proteins that could trigger an attack by a patient’s immune system.
A polymer gel developed by Joerg Lahann avoids these problems because the researchers are able to control all of the gel’s ingredients and how they combine. Lahann claims, “It's basically the ease of a plastic dish. There is no biological contamination that could potentially influence your human stem cells."
Now Lahann’s team has shown that the polymer surface can also support the growth of medically promising adult stem cells, keeping them in their high-potential state. To prove these cells could transform into different types, the team turned them into fat, cartilage, and bone cells.
The researchers then tested whether these cells could aid in the body’s own repairs. Specifically, they attempted to repair five-millimeter holes in the skull of mice. The weak immune systems of the mice didn’t attack the human bone cells, allowing the cells to help fill in the hole.
After eight weeks, the mice that had received the bone cells had 4.2 times as much new bone, as well as the beginnings of marrow cavities. The team could prove that the extra bone growth was derived from the new cells because it was human bone. For the future, Lahann’s team wants to explore using their gel to grow stem cells and specialized cells in different physical shapes, such as