What are stem cells? How advanced is medicine in this area?

You have heard a lot of news on the media about stem cells, and perhaps you have been wondering what is stem cell? How are they used to treat illnesses? Whether stem cells can help you or a loved one become seriously ill . Here are some answers to common questions about stem cells.

Why is there interest in stem cells?

Researchers and doctors hope that stem cell research can help:

1. Increased understanding of the mechanism of different types of diseases, why the disease occurs and how it occurs. By observing adult stem cells into cells in the bones, heart muscle, nerves, organs and other tissues, researchers and doctors can better understand disease.
2. Create healthy cells to replace sick cells. Stem cells can be cultured on purpose to become a certain type of cell, which can be used to regenerate and repair diseased or injured tissues in humans.

People who can be treated with stem cell therapy include people with spinal cord injuries, type 1 diabetes, Parkinson's disease, Alzheimer's disease, heart disease, stroke, burns, cancer and arthritis.

Stem cells can be developed into new tissues for use in transplantation and regeneration, opening up numerous opportunities for medical applications.

1. Stem cells can be used to test new drugs to see if they are safe and effective. Before using new drugs in humans, some types of stem cells are useful to check the safety and quality of research drugs.

Stem cells can be cultured into other cells.

New areas of research include the study of the effectiveness of using human stem cells programmed into specific tissue cells to test new drugs. To test new drugs correctly, cells must be programmed to obtain the properties of the tested cell types. Techniques to "program" the cells into the desired cells continue to be studied.

For example, nerve cells can be created to test a new drug for a neurological disease. Tests may show whether the new drug affects cells and whether the cell is damaged.

What are stem cells?

Stem cells are the body's materials - from which all other cells with specialized functions are created. Under proper conditions in the body or laboratory, stem cells divide into more cells called daughter cells.

These daughter cells become new stem cells (self-renewal) or become specialized cells (differentiated) with a more specific function, such as blood cells, brain cells, heart muscle or bone. No other cells in the body have the natural ability to create new types of cells.

Where do stem cells come from?

Researchers have discovered several sources to isolate stem cells:

1. Embryonic stem cells . These stem cells are derived from embryos three to five days old. At this stage, the embryo is called a blastocyst and has about 150 cells.

At this stage, the embryo is spherical and is called a blastocyst. Blastocyst has a three-component structure: an external cell layer (trophoblast), a fluid-filled cavity, and a group of about 30 universal cells that are deflected to a pole called inner cell mass (inner cell mass). ). Using a special enzyme to separate the cells of this block will yield embryonic stem cells.

This is called ploo-RIP-uh-tunt , which means they can divide into more stem cells or become any kind of cell in the body. This flexibility allows embryonic stem cells to be used to regenerate or repair diseased tissues and organs even though their use in humans today is limited to eye disorders such as macular degeneration. gold.

1. Adult stem cells . These stem cells are found in small amounts in most adult tissues, such as bone marrow or fat. Compared with embryonic stem cells, adult stem cells have a more limited ability to produce different cells of the body. Adult stem cells can also be found in children, the fetus and can be extracted from umbilical cord blood. In the body, the key role of adult stem cells is to maintain and repair the organization in which they are found.

Adult stem cells are versatile stem cells, which can develop into groups of closely related cells in the same organization.

For example, hematopoietic stem cells are capable of forming all types of blood cells including red blood cells, white blood cells, platelets, lymphocytes .

However, recent scientific evidence suggests that some types of adult stem cells may also be universal, or at least able to differentiate into many different types of cells (ie, flexibility. - plasticity).

Until recently, researchers believed that adult stem cells could only produce the corresponding cell type. For example, stem cells located in the bone marrow may only increase blood cells.

However, emerging evidence suggests that adult stem cells can produce unrelated cell types. For example, bone marrow stem cells can create bone or heart muscle cells. This study led to early clinical trials to test the usefulness and safety of humans. For example, adult stem cells are currently being tested in people with neuropathy or heart disease.

1. Adult cells have been modified to have the properties of embryonic stem cells. Scientists have succeeded in converting normal adult cells into stem cells by reprogramming the gene. By changing genes in adult cells, researchers can reprogram cells to function similarly to embryonic stem cells.

The new technique could allow researchers to use these reprogrammed stem cells instead of embryonic stem cells and prevent the reaction of new stem cells' immune systems. However, scientists still do not know which changes in adult cells will cause side effects in humans.

Researchers were able to take connective tissue cells regularly and reprogram them to become functional heart cells. In studies, animals with heart failure that had been implanted with new heart cells improved cardiac function and increased survival.

1. Perinatal stem cells. The researchers discovered stem cells in amniotic fluid, next to umbilical cord umbilical stem cells. These stem cells are also capable of changing into specialized cells.

Amniotic fluid is filled in the amniotic fluid that surrounds and protects the developing fetus in the womb. The researchers identified stem cells in the amniotic fluid samples of pregnant women in a procedure called amniocentesis, a test conducted to check for fetal abnormalities.

Still more research is needed on amniotic stem cells to understand their potential.

Pluripotent stem cells can divide into more stem cells or become any kind of cell in the body.

Why is there a debate about the use of embryonic stem cells?

Embryonic stem cells are obtained from early stage embryos - a group of cells that form when a woman's eggs are fertilized with male sperm in an artificial insemination room. Because embryonic stem cells are extracted from human embryos, a number of ethical questions and problems have been raised.

The US National Institutes of Health has released guidelines for human stem cell research in 2009. Guidelines include identifying embryonic stem cells and how they can be used in research and donation guidelines. for embryonic stem cells. In addition, the guide says embryonic stem cells can only be used from embryos produced by in vitro fertilization when embryos are no longer needed.

Where do these embryos come from?

Embryos are used in the study of embryonic stem cells taken from fertilized eggs in artificial insemination clinics in vitro but should never be implanted in a woman's uterus. The stem cells were donated with the consent of the donors. Stem cells can live and grow in special solutions in test tubes or petri dishes in the laboratory.

Why can't researchers use adult stem cells?

Although research on adult stem cells is quite potential, adult stem cells may not be as flexible and durable as embryonic stem cells. Adult stem cells may not produce all kinds of cells, limiting adult stem cells that can be used to treat the disease.

Adult stem cells are also more likely to contain abnormalities due to environmental hazards, such as toxins, or from errors obtained by cells during cloning. However, researchers have found that adult stem cells are much more adaptable than the original hypothesis.

What are stem cell chains and why do researchers want to use them?

A string of stem cells is a group of cells that all come from a single stem cell and are grown in the laboratory. Cells in the stem cell chain develop but do not distinguish into specialized cells. The ideal condition is that they still have no genetic defects and continue to produce more stem cells. Cell clusters can be taken from a chain of stem cells and frozen to store or share with other researchers.

What is stem cell therapy (regenerative therapy), and how does it work?

Stem cell therapy, also called regenerative medicine , promotes the recovery of diseased, inactive or damaged tissue by using stem cells or their derivatives. This is a sequel to organ transplantation and the use of cells instead of donated organs, which are very limited in quantity.

Researchers develop stem cells in the laboratory. These stem cells are made to specifically target specific types of cells, such as heart muscle cells, blood cells or nerve cells.

Specialized cells can then be transplanted into humans. For example, if a person with heart disease, cells can be implanted in the heart muscle. Healthy transplanted heart cells can then contribute to repairing defective heart muscle.

Researchers have shown that adult bone marrow cells are fed into heart-like cells that can repair heart tissue in humans.

Researchers created human pluripotent stem cells by modifying the cloning process.

Are there stem cells used to treat the disease?

Yes , the doctor has performed stem cell transplantation, also known as bone marrow transplantation . In stem cell transplantation, stem cells replace damaged cells due to chemotherapy or disease or as a way for the donor's immune system to fight certain types of cancer and diseases. related to blood, like leukemia. These transplants use adult or umbilical stem cells.

Researchers are testing adult stem cells to treat other diseases, including some degenerative diseases such as heart failure.

What are the potential problems when using human embryonic stem cells?

To benefit people, researchers must make sure that stem cells grow into the desired special cell types.

Researchers have discovered how to control stem cells to become specific cell types, such as directing embryonic stem cells into heart cells. Research is underway.

Embryonic stem cells can also activate the immune response, in which the recipient's body reacts to the stem cells like the invaders, or simply does not function normally, with the following unknown result. Researchers continue to study how to avoid these complications.

Is human therapy successful?

Not yet . Researchers were unable to successfully replicate human therapy despite success in some other species.

However, in recent studies, researchers have created human pluripotent stem cells by modifying the cloning process. Researchers continue to study the possibility of human therapy in humans.