In , a team of researchers from Massachusetts General Hospital reported in PNAS Early Edition that they had created blood vessels in laboratory mice, using human stem cells.
Within 2 weeks of implanting the stem cells, networks of blood-perfused vessels had formed. The quality of these new blood vessels was as good as the nearby natural ones. The authors hoped that this type of technique could eventually help to treat people with cardiovascular and vascular diseases. Scientists could use stem cells to replenish the damaged brain tissue.
This could bring back the specialized brain cells that stop the uncontrolled muscle movements. Researchers have already tried differentiating embryonic stem cells into these types of cells, so treatments are promising.
Scientists hope one day to be able to develop healthy heart cells in a laboratory that they can transplant into people with heart disease. Similarly, people with type I diabetes could receive pancreatic cells to replace the insulin-producing cells that their own immune systems have lost or destroyed. The only current therapy is a pancreatic transplant, and very few pancreases are available for transplant.
Doctors now routinely use adult hematopoietic stem cells to treat diseases, such as leukemia , sickle cell anemia , and other immunodeficiency problems. Hematopoietic stem cells occur in blood and bone marrow and can produce all blood cell types, including red blood cells that carry oxygen and white blood cells that fight disease. People can donate stem cells to help a loved one, or possibly for their own use in the future.
Bone marrow : These cells are taken under a general anesthetic, usually from the hip or pelvic bone. Technicians then isolate the stem cells from the bone marrow for storage or donation. Peripheral stem cells : A person receives several injections that cause their bone marrow to release stem cells into the blood. Next, blood is removed from the body, a machine separates out the stem cells, and doctors return the blood to the body. Umbilical cord blood : Stem cells can be harvested from the umbilical cord after delivery, with no harm to the baby.
Some people donate the cord blood, and others store it. For example, scientists have found that switching a particular gene on or off can cause it to differentiate. Knowing this is helping them to investigate which genes and mutations cause which effects. Armed with this knowledge, they may be able to discover what causes a wide range of illnesses and conditions, some of which do not yet have a cure.
Abnormal cell division and differentiation are responsible for conditions that include cancer and congenital disabilities that stem from birth. Knowing what causes the cells to divide in the wrong way could lead to a cure. Stem cells can also help in the development of new drugs.
Instead of testing drugs on human volunteers, scientists can assess how a drug affects normal, healthy tissue by testing it on tissue grown from stem cells. There has been some controversy about stem cell research. This mainly relates to work on embryonic stem cells.
The argument against using embryonic stem cells is that it destroys a human blastocyst, and the fertilized egg cannot develop into a person. Nowadays, researchers are looking for ways to create or use stem cells that do not involve embryos. Stem cell research often involves inserting human cells into animals, such as mice or rats. Some people argue that this could create an organism that is part human.
In some countries, it is illegal to produce embryonic stem cell lines. In the United States, scientists can create or work with embryonic stem cell lines, but it is illegal to use federal funds to research stem cell lines that were created after August However, most of these uses do not have approval from the U.
In some cases, can replace cells damaged by illness or injury. Adult cells that are reprogrammed to look and act like embryonic stem cells. From their embryonic-like state, can be further altered to become any other type of cell. Good potential use in medicine, but still a new area of research. Embryonic stem cells are the starter cells of the human body. They are undifferentiated, which means they have not matured and specialized, and they are able to become any other kind of cell in the body.
In embryos, these cells multiply and differentiate to become organs, bones and muscles. In the laboratory, they can be multiplied to create stem cell lines for study or for therapy. Scientists harvest embryonic stem cells from three- to five-day-old embryos donated by people who have gone through in-vitro fertilization. Scientists isolated the first human embryonic stem cells in What makes them different from other stem cells? These are the only stem cells that naturally are able to become any other cell type and to multiply endlessly.
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Clinical Trials. Article: p mediated mitochondrial function controls muscle stem cell proliferative fates. This can range from muscle cells to brain cells.
In some cases, they can also fix damaged tissues. Researchers believe that stem cell-based therapies may one day be used to treat serious illnesses such as paralysis and Alzheimer disease. Embryonic stem cells. The embryonic stem cells used in research today come from unused embryos. These result from an in vitro fertilization procedure. They are donated to science. These embryonic stem cells are pluripotent. This means that they can turn into more than one type of cell. Adult stem cells. There are 2 types of adult stem cells.
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