The How stem cells work.


How do stem cells work?

All of us have marveled at one point or another at how a baby can be created simply from various cells. And looking at any fetal growth chart will quickly tell you that two cells turns into dozens of cells that turn into hundreds and thousands of cells, until you can see a baby beginning to form. But just how does the human body do this? And how do those cells that make up the fetal form know that they are going to turn into a heart, an arm, or hair? It’s no wonder that creating another living being is so fascinating to us!

The secret behind all of human life are stem cells. These cells are packed into tiny embryos, which are what fetuses are called before they form fully enough to take on a visible form. Embryos are tiny, tiny masses of cells. They are so small in fact that they can fit onto the head of a pin. The cells that embryos are made up are called stem cells. Stem cells are known as being pluripotent, which means that they can develop into any cell, any muscle, any tissue, or any organ within the human body. While this allows for embryos to develop everything they need to in order for the human body to survive outside of the womb, stem cells also have another incredible power. Because they are pluripotent, they can also be used to treat different diseases and medical conditions.

Today stem cells are used to treat things such as adult diabetes, kidney cancer, and liver diseases. But doctors, researchers, and scientists are investigating ways to use stem cells even further and make their medical advancements even more fantastic! Imagine being able to restore memory cells to a person living with Alzheimer’s, or replacing skin that was lost in a terrible fire. These are just two of the things that stem cells have the capability to do. But first, researchers must first learn how to extract stem cells and properly use them, manipulate them, and capture their power.

What is a Stem Cell?

There are 220 different types of cells within the human body. Regular cells only have the ability to replicate and duplicate themselves. This means that tissue cells can only create tissue and organ cells can only create other cells for that particular organ. Stem cells on the other hand, are like a blank slate. They can be used to create any cell in the body. And because they also have the ability to self-renew, they can replicate themselves over and over again.

There are two different types of stem cells. The first type is embryonic stem cells and the other type is adult stem cells. Embryonic stem cells are what form a fetus in the earliest stages of life. These stem cells will grow into a fetus, which will grow into a baby and a person when they are implanted into a woman’s uterus. The embryo only has to be three to five days old before it becomes full of stem cells that will eventually make up the fetuses heart, eyes, brain, skin, and other parts of the body.

Adults also have stem cells within them. These lie within certain vital organs such as the heart, brain, bone marrow, lungs, and other organs. Adults have these stem cells so that their bodies can repair their organs when they become damaged. Whether it’s from an accident, an illness, or just everyday wear and tear on the organs, they begin to break down and become damaged. Adult stem cells can step in and reproduce the damaged cells, so that the organ works as effectively as it should. It was once believed that embryonic stem cells were more powerful than adult stem cells. This was because it was once thought that while embryonic stem cells can be reproduced to create any other cell in the human body, adult stem cells could only reproduce the same type of tissue from which they came. But, with more research being done all the time, this is being proven as untrue. For instance, it’s been proven that adult liver stem cells can also produce insulin, a job usually reserved for the pancreas. This capability known as plasticity or transdifferentiation, might only be one thing that adult stem cells have the powers to do.

How Stem Cells are Acquired and Worked in a Lab

Using stem cells for research first began in the 1980s when scientists started pulling these cells from mice and discovered ways to grow them in laboratories. Then in 1998 scientists also found ways to reproduce human embryonic cells. These human stem cells can be acquired through two different ways. Either reproduction of the human body using a sperm and an egg can be used, or through therapeutic cloning. To reproduce stem cells using a sperm and an egg, researchers and scientists have embryos donated to them from fertility clinics. This happens when a couple is trying to become pregnant and so they create the embryos outside of the body. Sometimes, too many embryos are created and the couple cannot have them all implanted. The extra embryos that are not implanted are then donated to science so that these researchers can continue to study the stem cells they contain.

Therapeutic cloning is a very complicated process that to fully understand would take an article of its own. But here we’ll break it down as simply as possible. Cloning uses a cell from the patient that needs the treatment and merges it with an egg given by a donor. The nucleus is then taken out of the egg and replaced with the cell taken from the patient. The egg is then activated through either electricity or with chemicals and it then divides. This creates a new embryo that contains the patient’s genetic matter. This reduces the chance that the patient’s body will reject the new embryo once it’s implanted.

Once an embryo has grown for three to five days, it’s then called a blastocyst. Blastocysts are made up of about 100 cells. The stem cells are those that are found in the innermost part of the blastocyst. And it is from here that researchers will remove the stem cells and place them into a Petri dish to grow in a solution that’s rich with nutrients. The stem cells will then begin to grow and multiply and eventually, become far too large to continue to sit in the Petri dish. Then at this time, the cells will be divided up into multiple Petri dishes so that they can continue to be cultivated. This will continue on for several months until the stem cells make up a stem cell line. A stem cell line is a group of stem cells that have been grown and cultivated, without differentiating in any way. Cell lines are often frozen and shared amongst different laboratories.

While this may all sound quite basic, acquiring and controlling stem cells within a laboratory environment is very difficult. Researchers are always trying to find new and better ways to control stem cells, and manipulate them to do what they want them to do. Adult stem cells are especially difficult to work with in the laboratory. This is because stem cells are more difficult to find in adults and also because adult stem cells don’t replicate as well within the lab.

The Rewards and Challenges of Stem Cells

What scientists are working mostly on now is using stem cells to treat disease. They’d like to be able to do this by simply injecting new stem cells into a patient’s body where it would replace any damaged cells. While this is the ideal situation, it’s still not possible because scientists haven’t yet been able to direct a cell to differentiate into a particular cell or tissue. This means that scientists haven’t yet found a way to get a stem cell to develop into a liver or a brain cell once it’s inside the human body. And even if they do find a way to differentiate the cells, scientists still don’t know how they would control them once inside the patient. Another problem found when working with stem cells is that there’s no way to make sure that the patient’s body won’t reject the cell once it’s injected into their body. This sometimes happens when the person’s immune system senses that the stem cell is a foreign body within the human body. Because of its natural abilities, the immune system will then label the cell as a danger and will destroy it.

In nature, stem cells are given external and internal cues that tell the stem cells what to do and how to function within the body. The internal cues come from the genes found inside the stem cells. The external cues are chemicals given by the body and surrounding cells that tell it how to act. Being able to turn the genes on and off within a stem cell is crucial to getting stem cells to differentiate. Scientists know this and so they try to replicate that process by injecting certain genes into Petri dishes. This will hopefully get the stem cells to develop into a certain type of tissue, muscle, or other cell. But there is still a long way to go. In order to make this occur within the Petri dish, a signal needs to be given to the cells and it is this signal that researchers are still trying to create to get the process started.

But, if these challenges can be overcome and scientists can find a way to control and manipulate the stem cells once they are injected, the benefits of stem cells are immeasurable!

The first way that stem cells could be used is to test new medications. Today these medications need to go through rigorous testing and clinical trials, which take a lot of time and money. However, stem cells could replace this to test the safety and effectiveness of these new medications. For instance, cancer medication could be applied onto stem cells that have tumor growth on them. The cells can then be studied to see if the medication stops the tumors from growing, and if the cells have any adverse effect on the stem cells.

Of course, stem cells could also be used to recreate damaged cells and inject them into a patient to treat them for a disease or medical condition. But scientists want to expand on this idea even more and be able to eventually produce entire organs right in a laboratory setting. Imagine what a medical breakthrough this could be with people no longer being on mile-long wait lists while they wait for a transplant for a heart, kidney, or other type of organ.

So Why the Controversy?

With all the fabulous medical advancements that stem cells seem to be creating, why would anyone fight the development and production of them? The reason is that stem cells cannot be made on their own and that they must be taken from embryos. And in order to do that, the embryo must be destroyed. Although the embryos are only three to five days old when this happens, some religious and pro-life activists argue that this is the destruction of human life. Even though that life is still only a clump of cells in a dish, if it’s not destroyed for stem cells, it could grow into being a human being. The argument is that taking a human life for any reason is wrong.

The other argument against sperm cell research is that it makes cloning problem. Although this was always at the back of the minds of those that opposed stem cell research, the fear became a reality in 1997, when researchers in Scotland were able to clone a sheep, that they named Dolly. The thought is that if researchers can clone a sheep they can also clone a human being. The problem with this is that arguers state that people should not be allowed to play God, and dictate what life is given. Also, another fear with cloning humans is that researchers and scientists might try to create superhumans. These humans might have greater intellectual abilities than even the brightest minds, or have superhuman strength that could pose a real danger to today’s society.

Scientists are also doing a lot to reduce the fears that people associate with stem cell research. One thing they are doing is working more with adult stem cells so that embryos needn’t be destroyed in the process of research. While these stem cells are more difficult to obtain and manipulate, advances are being made in this area as well to make them more workable and flexible. However, because there are still many advocates against stem cell research, the research is now being heavily monitored by governments across the world. Stem cell funding is also restricted to appease the controversy.

stem cells.

 How stem cells work.