In an effort to understand how disease functions and how to counter its destructive effect on human life, scientists have been conducting Stem Cell Research since the early 1900s.
Stem cells are cells that can become many different kinds of tissue. There has long been interest in using them to replace cells damaged by disease and even to grow transplant organs with them. Great strides have been made in the field in the last several years due to advances in technology.
The research is bound up in ethical concerns and is very costly. The government had funded some of the research, but in 2015 taxpayer support was suspended. Now, stem cell studies are funded by private foundations. There have been significant breakthroughs made. Here are five of them.
Research into Adult Stem Cells
The ethical problems of studying stem cells have caused much debate and delay in the field. This is because scientists have used human embryonic cells created when cells divide. The stem cells are harvested when the embryo is only a few days old, but harvesting the cells kills the embryos. That sparks debate with people who support the sanctity of human life at all stages. Now, researchers have been able to isolate adult stem cells. These cells can be reprogrammed to act like embryonic cells. Another name for them is Induced Pluripotent Stem Cells. They are more stable then embryonic cells, but seem to be a little less flexible. Nevertheless, when used in creating a custom medicine for a patient, or a transplant organ, the adult cells could eliminate the rejection process of the body because the cells would come from the patient himself.
Stem Cell Research on Disease in a Dish
Scientists have used stem cells to create diseases in the laboratory. Studies in human subjects are limited because doctors cannot experiment on sick people. They can study the diseased cells at a microscopic level, however, when they are grown in the lab. Scientists used stem cells taken from ALS patients and turned them into motor neuron cells. These are the cells ALS damages. Using the altered cells, researchers can study the disease and its responses to different drug therapies.
Research on Stem Cells and Chemotherapy
Doctors have long wondered why cancer treated successfully with chemotherapy sometimes comes back years later. The answer seems to lie in stem cells. Adult stem cells in the body become cancer stem cells which produce the actual cancer cells. After producing the cancer stem cells, the adult stem cells hibernate. Chemotherapy only targets active cells, so it kills the cancer cells, but not the dormant stem cells which produced them. Years later, those cells can wake up and produce the cancer cells again. Knowing that, researchers hope to develop drug therapies that will target the cancer stem cells.
New, Cheap Method of Producing Stem Cells
Researchers have found that they can turn various types of cells into stem cells. Even skin cells will work. They can do this by injecting them with foreign DNA. The process takes time and is costly. In addition, there are risks in introducing genetic material into subjects. Recent studies have shown that putting the cells in an acidic environment seems to mimic the way they develop in nature and is much cheaper, faster and safer than other methods.
Research on Stem Cells to Grow Transplant Organs in Animals
One of the newest developments in stem cell studies involves using a chimera as a host for a transplant organ. Chimeras are animals with cells of different species. In this case, scientists injected human stem cells into a pig embryo, then placed the embryo inside a sow. They removed the embryos after a month of development and found the human cells still maintained their integrity. Not only that, but they had begun to form the beginnings of a pancreas, a liver and other organs. The focus now is on keeping the cells from integrating with the pig cells, so the pig brain, sperm and eggs do not contain human material. It is very early in the research, but researchers hope to grow human transplant organs in the animal and then harvest them.
Science, for all its research, is still in the infancy of these studies. There are many practical, theoretical and ethical issues to resolve in the field of stem cell research.