|Dr. Carol Ware working in her laboratory at the |
Institute for Stem Cell and Regenerative Medicine
"These cells will allow us to gain a much greater understanding of normal embryonic development and have the real potential for use in developing ways to grow new tissues and organs for transplantation." said Carol Ware, a professor of comparative medicine and leading author of the paper.The findings appear in the March 10 issue of the journal Proceedings of the National Academy of Sciences.
The cells, called naïve embryonic stem cells, normally appear at the earliest stages of embryonic development. They retain the ability to turn into any of all the different types of cells of the human body -- a capacity called "pluripotency."
Researchers had been able to develop naïve cells using mouse embryonic stem cells, but to create naive human embryonic stem cells has required inserting a set of genes that force the cells to behave like naive cells.
While these transgenic cells are valuable research tools, the presence of artificially introduced genes meant the cells will not develop as normal embryonic cells would nor could they be safely used to create tissues and organs for transplantation.
In an article, Ware and her colleagues from the UW Institute for Stem Cell and Regenerative Medicine describe how they successfully created a line of naïve human embryonic stem cells without introducing an artificial set of genes.
They first took embryonic stem cells that are slightly more developed, called primed stem cells, and grew them in a medium that contained factors that switched them back -- or "reverse toggled" them -- to the naïve state. They then used the reverse toggled cells to develop a culture medium that would keep them in the naïve state and create a stable cell line for study and research.
While the "reverse toggled" cells are much easier to create and will prove valuable research tools, Ware said, the cells that were directly derived from embryos are the more important advance because they are more likely to behave, grow and develop as embryonic cells do in nature.
The new cell line is called Elf1: "El" for the Ellison Foundation, a major supporter of the lab's work; "f" for female, the sex of the stem cell; and "1" for first.
- Ware CB, Nelson AM, Mecham B, Hesson J, Zhou W, Jonlin EC, Jimenez-Caliani AJ, Deng X, Cavanaugh C, Cook S, Tesar PJ, Okada J, Margaretha L, Sperber H, Choi M, Blau CA, Treuting PM, Hawkins RD, Cirulli V, & Ruohola-Baker H (2014). Derivation of naive human embryonic stem cells. Proceedings of the National Academy of Sciences of the United States of America PMID: 24623855