Stem cells are special human cells that have the ability to develop into many different types of cells, from muscle cells to brain cells. They can become any cells the body requires, because they have the ability to transform when needed.

What are stem cells?

Stem cells are the cells that give rise to all other cells with more specific and specialized functions found in the body, such as blood cells, brain cells, heart muscle cells, bone cells and other specialized cells.

Stem cells begin to divide in the appropriate conditions, whether in the body or in the laboratory, to form more cells called daughter cells, so that the daughter cells become either new stem cells that can self-renew or may become cells with a specific function, it is worth noting that there is no other cell in The body has the natural ability to produce new types of cells other than stem cells.

Scientists are interested in stem cells because they help explain the mechanism of some body functions and how they sometimes go wrong, and research on stem cells shows promising results in treating some diseases that currently have no cure, but you must first know the types of these stem cells, their functions, and their composition. So you can understand how it works.

Types of stem cells and how they are formed

Stem cells are produced from two main sources: body tissues and adult embryos. However, scientists have also worked to find ways to develop stem cells from other cells to produce two other types of stem cells in the laboratory using genetic reprogramming techniques: mesenchymal stem cells and iPS cells. Capabilities to eventually divide stem cells into 4 types as follows:

1- Adult stem cells

Adult stem cells are a type of stem cell, but they remain in a state of complete dormancy, so they do not divide like other stem cells and do not renew indefinitely, even years until the body needs them to repair or grow new tissues, where adult stem cells can divide or self-renew into Indefinitely.

This enables them to generate different types of cells from the original organ or even completely regenerate the original organ. This division and regeneration is how a skin wound heals or the wound healing mechanism, or how an organ like the liver can repair itself after damage.

In the past, scientists believed that adult stem cells could differentiate or specialize only based on their tissue of origin, but now, however, some evidence indicates that they can differentiate into other types of cells as well. Unspecialized stem cells found in skin tissue can develop into Liver tissue stem cells.

Stem cells are found within different types of tissues. Scientists have found stem cells in the following tissues:

• the brain.
• bones.
• the blood.
• Blood vessels.
• Skin.
• liver.
• Skeletal muscles.

The existence of stem cells continues in the human body throughout his life, as the body can use these stem cells whenever it needs them.

2- Embryonic stem cells

Embryonic stem cells are obtained through a blastocyst of a 4-5-day-old embryo, where in the first stage of pregnancy the embryo is formed after the sperm fertilizes the egg specifically, after about 3-5 days of the fertilization process, the embryo takes the form of a blastocyst or a ball of cells Which contain embryonic stem cells that will later be implanted in the uterus.

Scientists take stem cells from embryos, which are usually additional embryos resulting from in vitro fertilization (IVF) – artificial insemination – where in IVF clinics doctors fertilize several eggs in a test tube to make sure that at least one survives, and then they implant A limited number of eggs to start a pregnancy.

The blastocyst consists of about 150-200 cells and is divided into two parts:

• An outer cell mass that becomes part of the placenta.
• An inner cell mass that develops into the human body.

The inner cell mass is where embryonic stem cells are located. Scientists call these cells full potential because they have full potential to develop into any cell in the body. With the right catalyst, they can develop into blood cells, skin cells, and all kinds of other cells that the body needs. .

The blastocyst stage lasts for about 5 days before the embryo implants in the uterus, after which embryonic stem cells begin to differentiate, as they can differentiate into more cell types than adult stem cells.

3- Mesenchymal stem cells (MSCs)

Mesenchymal stem cells are a type of stem cell discovered by scientists that are obtained from the connective tissue or that surrounds body organs and other tissues, and scientists used these cells to create new tissues for the body such as bone, cartilage, and fat cells, and they may be used and further researched in the future To solve a wide range of health problems.

4- Induced high-potential stem (iPS) cells

Induced pluripotent stem cells (iPS) are a type of cells that are formed in the laboratory under special conditions using embryonic or adult cells such as skin cells or other tissue cells, to have the same characteristics as embryonic stem cells but with high capabilities that can be used in Develop a range of therapies.

stem cell function

Stem cells do not have one specific function, but with the right stimulation, they can play the role of any other type of cell in the body, and they can regenerate damaged tissues when the body requires it, this potential can save lives or heal wounds and tissue damage in people after any disease or infection, Its functions include the following:

1- Tissue regeneration

One of the most important functions of stem cells is to regenerate body tissues, as a patient who needs a new kidney had to wait for a donor and then undergo a transplant, but there is a shortage of donor organs, but by directing stem cells to differentiate in a certain way, scientists were able to use them to grow a type or organ specific tissue.

In another case, doctors have already used stem cells from just below the surface of the skin to make new skin tissue, which they can then repair severe burns or any other injury by grafting this tissue onto the damaged skin, then the new skin will grow back.

2- Treatment of cardiovascular diseases

In 2003, a team of researchers from Massachusetts General Hospital produced new blood vessels by cultivating human stem cells, and the experiment succeeded in mice, where within two weeks of stem cell transplantation, networks of blood vessels were formed, the quality of which is as good as normal vessels.

Scientists hope this type of technology will eventually help treat people with cardiovascular disease, but more research and trials are needed.

3- Treatment of brain diseases

After research, doctors may be able to use replacement cells and tissues to treat brain diseases such as Parkinson’s disease and Alzheimer’s disease, where in Parkinson’s disease, brain cell damage leads to uncontrolled muscle movements, but scientists can use stem cells to regenerate damaged brain tissue, which restores specialized brain cells that inhibit Uncontrolled muscle movements.

4- Treatment of cell deficiency

Scientists hope to be able to grow healthy heart cells in the laboratory that they can transplant into people with heart disease. These new cells can repair heart damage by repopulating the heart with healthy tissue.

Similarly, people with type 1 diabetes could receive pancreatic cells to replace insulin-producing cells that have been lost or damaged by their immune systems, rather than a pancreas transplant.

5- Treatment of blood diseases

Doctors now use adult hematopoietic stem cells to treat diseases such as leukemia, sickle cell anemia and other immunodeficiency problems. Hematopoietic stem cells occur in the blood and bone marrow and stem cells can give rise to all types of blood cells, including blood cells. Red blood, which carries oxygen, and white blood cells, which fight disease.

Is there any harm resulting from stem cells?

Many are looking for stem cell damage, but there is no harm to it at all, while treatment using embryonic stem cells in humans can cause health problems, as it may cause the body’s immunity to be stimulated, making it attack those cells as an unwanted foreign body, or it can These cells can fail to function normally with unknown consequences.

The embryonic cells that will be used for therapies can also differentiate or specialize into cells other than the required cells, which may lead to health problems whose consequences are not yet known, so doctors are still studying how they can make these cells differentiate into the required cells to avoid these consequences.