Stem cells are cells that have the ability to develop into other types of cells. They can, for example, develop into muscle or brain cells. They can also renew themselves by dividing after being dormant for a long time.
Stem cell research is assisting scientists in understanding how an organism develops from a single cell and how healthy cells can be used to replace cells that are not functioning properly in humans and animals.Researchers are now investigating stem cells to see if they can aid in the treatment of a variety of conditions affecting various body systems and parts.
This article discusses different types of stem cells, their potential applications, and some ethical concerns about their use.
The human body requires many different types of cells to function, but not every cell type is fully formed and ready for use.
A stem cell is referred to as a “undifferentiated” cell by scientists because it has the potential to become any cell. A blood cell, on the other hand, is a “differentiated” cell because it has already formed into a specific type of cell.The sections that follow go into greater detail about various types of stem cells.
Embryonic Stem cells
Scientists isolate embryonic stem cells from unused embryos left over from IVF procedures. They do this by harvesting cells from embryos at the blastocyst stage, which is the stage before the embryo implants in the uterus.These are undifferentiated cells that divide and multiply. However, they are also able to differentiate into specific types of cells.
Adult Stem Cells
Adult stem cells are classified into two types: those found in developed bodily tissues and those found in induced pluripotent stem (iPS) cells.Some stem cells can be found in developed bodily tissues such as organs, muscles, skin, and bone. Based on their location, these cells can typically differentiate into differentiated cells.
A brain stem cell, for example, can only become a brain cell.Scientists, on the other hand, manipulate iPS cells in order to make them behave more like embryonic stem cells for use in regenerative medicine. After collecting the stem cells, scientists usually store them in liquid nitrogen for future use. However, researchers have yet to convert these cells into any type of bodily cell.
Uses
Scientists are researching how to use stem cells to regenerate or treat the human body.The list of conditions that stem cell therapy could help treat may be endless. Among other things, it could include conditions such as Alzheimer’s disease, heart disease, diabetes, and rheumatoid arthritis. Doctors may also be able to use stem cells to treat injuries in the spinal cord or other parts of the body.
They may do this in several ways, including the following.
In Therapy
Because stem cells can easily divide to replace dead cells, they play an important role in regeneration in some tissues. Scientists believe that understanding how stem cells function will aid in the treatment of damaged tissue.For example, if a person’s heart contains damaged tissue, doctors may be able to stimulate the growth of healthy tissue by transplanting laboratory-grown stem cells into the person’s heart. This may cause the heart tissue to regenerate.One study found that people with heart failure improved two years after receiving a single dose of stem cell therapy. However, the impact of stem cell therapy on the heart is still unknown, and research is ongoing.
Another study suggested that stem cell therapies could form the foundation of personalised diabetes treatment. Researchers successfully generated insulin-secreting cells from stem cells derived from the skin of people with type 1 diabetes in mice and laboratory-grown cultures.”What we’re envisioning is an outpatient procedure in which some sort of device filled with the cells would be placed just beneath the skin,” said study author Jeffrey R. Millman, an assistant professor of medicine and biomedical engineering at Washington University School of Medicine in St. Louis, MO.Millman anticipates that these stem cell-derived beta cells will be ready for human research within the next 3-5 years.Stem cells may also hold enormous promise in the development of new therapies.
Drug Development
Another application for stem cells could be in the development and testing of new drugs.The iPS cell is a type of stem cell that scientists commonly use for this purpose. These are cells that have already differentiated but have been genetically “reprogrammed” by scientists through genetic manipulation, sometimes using viruses.In theory, this allows iPS cells to divide and differentiate into any cell. In this way, they could behave similarly to undifferentiated stem cells.Scientists, for example, want to create differentiated cells from iPS cells that resemble cancer cells and use them to test anticancer drugs. This is possible because conditions such as cancer and some congenital disabilities occur as a result of abnormal cell division.
Current Stem Cell Therapy
Clinics that provide various types of stem cell treatments have opened in recent years. According to one 2016 study, there are 570 of these clinics in the United States alone. They appear to provide stem cell-based therapies for a wide range of conditions, from sports injuries to cancer.Most stem cell therapies, however, are still theoretical rather than evidence-based. For example, researchers are investigating how to use amniotic fluid stem cells — which experts can save after an amniocentesis test — to treat a variety of conditions.The Food and Drug Administration (FDA) permits clinics to inject people with their own stem cells as long as the cells are only used for their normal function.
Aside from that, the FDA has only approved the use of hematopoietic progenitor cells, which are blood-forming stem cells. These are derived from umbilical cord blood and used by doctors to treat conditions that affect blood production. Currently, a doctor can save blood from an umbilical cord after a baby is born for this purpose in the future.On its website, the FDA lists specific approved stem cell products, such as cord blood, as well as the medical facilities that use them. It also cautions people against undergoing unproven treatments because very few stem cell treatments have even reached the early stages of a clinical trial.
Ethical Aspects
The use of stem cells in medical research has historically been contentious. This is due to the fact that when the therapeutic use of stem cells was first brought to the public’s attention in the late 1990s, scientists were only deriving human stem cells from embryos.Many people are opposed to using human embryonic cells for medical research because extracting them involves the destruction of the embryo.
This creates complex issues because people have different ideas about when human life begins.For some, life begins with the birth of a child, while for others, it begins with the development of an embryo into a foetus. Meanwhile, others believe that human life begins at conception, and that an embryo has the same moral standing and rights as a human child.
Former U.S. president George W. Bush had strong antiabortion views. He believed that an embryo should be considered a life and not be used for scientific experiments. Bush banned government funding for human stem cell research in 2001, but former U.S. president Barack Obama then revoked this order. Former U.S. president Donald Trump and current U.S. president Joe Biden have also gone back and forth with legislation on this.However, by 2006, researchers had already started using iPS cells.
Scientists do not derive these stem cells from embryonic stem cells. As a result, this technique does not have the same ethical concerns. With this and other recent advances in stem cell technology, attitudes toward stem cell research are slowly beginning to change.
However, there are still some concerns about using iPS cells. This includes ensuring that biological material donors provide proper consent for iPS cell extraction and carefully designing any clinical studies.Researchers are also concerned that manipulating these cells as part of stem cell therapy may result in the development of cancerous tumours.
Summary
Although scientists must conduct much more research before stem cell therapies can be used in routine medical practise, the science surrounding stem cells is constantly evolving.
Scientists continue to study embryonic stem cells, but research into iPS cells may help alleviate some of the ethical concerns surrounding regenerative medicine. This could lead to much more personalised treatment for many conditions, as well as the ability to regenerate human body parts.