Stem cells can accelerate basic research
In addition to replacing lost or damaged tissue, stem cells are expected to accelerate the type of basic drug discovery, drug screening, and disease research that is currently underway. Learn more about the many ways stem cells are used in basic medical research.
- How can pluripotent stem cells speed drug screening?
- How can stem cells model human disease?
- How can stem cells address infertility?
Stem cells are expected to dramatically improve the ability of drug companies to screen for side effects of new drugs much earlier in the development process, a benefit that would significantly lower the costs and speed the timeframe of developing a new drug. Currently, all drugs go through extensive animal trials before they are ever given to people. However, animals aren’t humans. Drugs that appear perfectly safe in animals often have dramatic side effects in people.
The ideal solution to the problem of drug side effects would be to test the drugs on human cells before the drugs enter human clinical trials. The most common drug side effects are on the liver, kidney, and heart. For that reason, those are the tissues people are trying to create from pluripotent stem cells to use for screening drug toxicity.
The idea behind toxicity screening using human stem cells would be that drug companies would have banks of stem cells from embryos and people with a wide variety of genetic backgrounds. They could then grow heart, liver, or kidney cells created from those stem cells in the presence of a drug. If those cells show signs of toxicity that would indicate that the drug isn’t a good candidate for human trials.
This work also could reveal groups of people with genetic backgrounds that either do or don’t respond well to a given drug. This type of personalized medicine would allow drug companies to develop drugs that are safe and effective in targeted groups of people.
Stem cells provide a powerful tool for studying how a disease develops in human cells. Pluripotent stem cells created via iPS or SCNT are genetically identical to the person who donated the cell to create the lines. If that person has Parkinson’s disease, for example, researchers can grow those cells in a dish and differentiate them into the type of neurons that go bad in Parkinson’s disease. Stem cell researchers can then study the cells to understand what goes wrong when they begin forming the disease in the dish. These studies could lead to better ways of detecting the disease at an early stage or to developing treatments. For example, if disease-specific cells in a dish behave like the disease tissue, drug companies could use them to find compounds that improve or reverse the disease.
Many CIRM-funded researchers are studying and developing disease-specific cell lines. Some of these lines come from IVF embryos that weren’t implanted into the mother because genetic testing showed that they contained known disease mutations. These blastocysts would have been discarded had researchers not seen the potential to use the stem cells to understand and treat human disease. Other disease-specific lines are being developed through iPS.
Embryonic stem cells provide the only glimpse of what happens in the earliest days of human development. One of the earliest decisions these cells make is whether to become cells of germ line – the cells that make up the eggs and sperm. Some researchers think that forms of infertility may start at this early stage. Information that comes from studying embryonic stem cells as they develop into sperm or eggs could help treat some of the 30% of couples who have infertility issues.