What are stem cells and why are they needed?

What are stem cells?

First, a few basics. The brain, muscles, internal organs from the heart to the kidneys, bones, skin - all the elements of our body are composed of cells. But they are very different from each other. "Muscle" cannot replace a bone tissue cell. "Hepatic" will not become cerebral. The cells that make up the kidneys are completely different from skin cells.

Stem cells can become cells of any organ

There is only one thing that unites them: they all once evolved from stem cells: What they are and what they do (undifferentiated, "undefined") cells.

Stem cells are what a post-conceptional embryo is made of at the earliest stages of its development with Embryonic Stem Cells.

After implantation into the uterus, the embryo begins to actively develop. During this period, undifferentiated cells are "defined". Some of them become cells of the nervous system, others begin to form bones, and still others - internal organs.

In fact, stem cells are the raw material from which a just nascent organism completely builds its own organs and tissues, turning from a tiny zygote into a child.

Why is there so much talk about stem cells?

Stem cells can be called the same "magic pill" for all diseases. And not only.

Any element of our body can be grown from them. If you break your arm, stem cells will help repair the bone, making it young, strong and healthy again - just like when you were young, even if you are much older. If you have cirrhosis of the liver, stem cells will grow fresh hepatocytes, and the organ will work like new. The same applies to problems with other internal organs, muscles, blood vessels.

Stem Cells speculates that one day, stem cells will be able to defeat Parkinson's disease, Alzheimer's disease, spinal cord injury, heart failure, diabetes and arthritis.

Undifferentiated cells make it possible to rejuvenate the body at any time: from the heart, bones, eyes, teeth to skin and hair.

The scientific field that studies the ways of using stem cells is called regenerative medicine Stem cells: What they are and what they do (also known as stem cell therapy).

Only embryos have stem cells?

No. There are Stem cells: What they are and what they do four types of stem cells, differing in origin and capabilities.

1. Embryonic stem cells

They are made up of embryos approximately 3-5 days after fertilization of the egg. At this stage, the embryo is called a blastocyst. It contains about 150 cells.

These are the most versatile stem cells: they can potentially become the basis of any organ and tissue.

2. Adult stem cells

Every person has them. True, in a minimal amount. Their task is to grow new cells to recover from various types of damage. There is a droplet of stem cells in the heart, liver, kidneys. But most of them are in the bone marrow and adipose tissue.

The downside of this type is low versatility. Previously, researchers generally believed that adult cells are capable of transforming only into elements of the organ in which they are located. For example, those found in the bone marrow can only give rise to blood cells. Later it turned out that particles from the bone marrow can also create bone or heart muscle cells. But research is still underway, and scientists are far from always able to turn adult stem cells into elements of the desired organ.

3. Induced stem cells (ISC)

Scientists have learned how to transform ordinary cells into stem cells - using genetic reprogramming. For example, cells taken from connective tissue have been transformed into heart cells. Experiments on animals with heart failure have shown that ISCs actually improve heart function and prolong life.

But researchers have not yet risked experimenting on people.

4. Perinatal stem cells

This is the name for undifferentiated cells that have been found in cord blood and amniotic fluid (amniotic fluid). There are not so many of them, but they are also capable of transforming into almost any specialized cells.

Is Regenerative Medicine already working?

Let's just say: actively trying. For example, some works featured How Do Stem Cells Work? that stem cell therapy really helps in the treatment of injuries and diseases of the musculoskeletal system - osteoarthritis, tendon and ligament ruptures, lumbar disc degeneration, non-healing bone injuries.

Another, even more common use of regenerative medicine is stem cell transplant (or bone marrow transplant). This procedure is used by Stem cells: What they are and what they do for certain types of blood cancer: leukemia, lymphoma, neuroblastoma, multiple myeloma. For transplant, adult stem cells from a donor or obtained from umbilical cord blood are used. They replace the bone marrow of a patient who has suffered from chemotherapy or illness.

But stem cell research is still ongoing V. How does NIH support stem cell research? … Therefore, regenerative medicine has not yet become widespread. And chances are it won't.

This means that the secret of eternal youth and health has been found, it remains only to refine it?

Stem cell therapy is indeed a very promising medical field. However, it is associated with a number of problems with Stem cells: What they are and what they do.

Undifferentiated cells, having entered the body of an adult, cause the development of not only healthy cells, but also those that have pathologies. The older the patient, the higher this risk.
The human immune system sometimes overreacts to donor stem cells. The body violently attacks "invaders", and this can lead to unpredictable health consequences.
Embryonic stem cells are considered the most versatile and safe. But how humanely it is to use human embryos (even those that were created in a test tube specifically for medical purposes), neither researchers, nor doctors, nor society as a whole have yet decided.

It will be possible to talk about the widespread use of regenerative medicine only after science has found answers to the questions posed. But this is still a long way off.