Stem Cells- Charlotte

Stem Cells

Figure 1: Diagram showing the use of stem cells in different tissues of
the human body

--> What are stem cells?

A stem cell is an immature cell that can become specialized into different types of cells in the body (source). There are two known basic types of stem cells: adult stem cells and embryonic stem cells. 
Embryonic stem cells are made when a newly fertilized egg begins to divide. This specific type of stem cells is able to grow into any type of cell found in the body. Adult stem cells divide regularly to create new specialized cells to replace other lost or dead cells. They have predetermined types of cells that they can generate and are usually present in already developed tissues including brain, blood, muscle, skin and bone tissues. 

--> Therapeutic potential of stem cell

• Testing new drugs for effectiveness and safety: Some types of stem cells can be used for testing new drugs instead of testing them directly on a person. To ensure their safety and effectiveness, specific cells that the disease affects have to be produced. This enables us to stop testing on animals, preventing the sacrifice of animals for drug testing and allowing us to generalize the results to humans. Additionally, testing new drugs directly on stem cells can save time and money.

• Increasing our understanding of how diseases occur: Scientists can observe stem cells maturing into cells in bones, heart muscle, nerves, and various other organs and tissues to understand how diseases develop. For example in Parkinson's disease, the reason why neurons in the brain die remains unknown. It is very hard for scientists to have access to neurons from a Parkinson's disease patient's brain, so they are trying to make neurons directly from stem cells to investigate the causes of the disease. (source)

Figure 2- Diagram showing how haematopoietic stem cells
 can be used to treat  patient with Leukemia

• Creating healthy cells to replace damaged or lost cells and treat diseases: To treat heart failure, scientists could potentially stimulate stem cells to differentiate into heart cells and inject them into a patient's heart. Inside the heart, the new cells could grow and replace damaged or dead tissue cells. Scientists have not yet been able to stimulate stem cells to differentiate into heart cells but they have tested this concept in mice with damaged hearts. (source) The mice showed improvement in heart function and blood flow, proving that stem cells have a great potential to treat heart conditions if scientists develop a system to differentiate stem cells. As we can see in Figure 2, stem cells could potentially treat multiple other diseases that involve tissue and cellular destruction such as leukemia, Parkinson's disease, Diabetes, spinal chord injuries and retinal diseases. (source)

--> Ethical considerations of stem cell therapy

Figure 3- Diagram showing the process of making embryonic stem cells

Although stem cells have a lot of potential, they bring up a significant ethical issue that causes people to debate over whether stem cell research should continue. To obtain embryonic stem cells, which are said to have more potential due to the fact that they can become all types of cell in the body, the early embryo must be destroyed (see Figure 3). This means that a potential human life is destroyed, raising the argument of whether the embryo should already be considered a person or a potential person. On the other hand, if stem cell research continues, scientists could find cures to deadly diseases and a huge number of people suffering from these diseases could be treated. "I understand that many have ethical and moral reservations about stem cell research, but for the same reason I describe myself as pro-life, I embrace embryonic stem cell research because I believe being pro-life is not only caring for the unborn but also caring for the living."“ (U.S. Sen. Orrin Hatch of Utah)

Stem Cell

STEM CELLS

This image shows the stem cell spiting and becoming different types of cells.

What are Stem Cells?

Stem cells- plural noun: an undifferentiated cell of a multi-cellular organism which is capable of giving rise to indefinitely more cells of the same type, and from which certain other kinds of cell arise by differentiation

That is the standard definition given to us by google when we ask what a stem cell is, but what does that actually mean? 

This means that one little stem cell can essentially become any cell imaginable as seen in the picture above. It could become a heart cell, blood cell, brain cell, you name it and a stem cell has the potential to become it.

That is why it is such a cool thing that Stem Cells have the potential to become many different cell in there early life and growth.

Stem cells have therapeutic potential to help treat type 2 diabetes. Researchers turned stem cells into insulin and it helped to treat people with diabetes. Stem cells can help because people with diabetes do not produce or use insulin (the hormone) properly. 

Some people believe that stem cell research is not ethical and that it causes harm and violates the embryo, while other people believe it "shows respect for human life" as stated in the last link. 

I believe that research is research, it can be good or bad and that everyone has there own opinion. No matter what research is done there will always be someone to oppose or dislike the research. We all have to discover if research is ethical to us.

Stem Cell Potential

Human body is composed from differentiated cells (Picture 2) which are the cells with a specific function, and undifferentiated cells which are called stem cells (Picture 1). Stem cells are non-specialized cells that have the potential to become any other type of cell, that is to develop a specialized function.

Picture 2: Differentiated cells

Picture 1: Stem cell

There are two types of stem cells. Embryonic stem cell (ES) and adult stem cell. Adult stem cell have the ability to differentiate into only some cells while ES can differentiate into any cell. Because some people think it is unethical extracting ES, scientist are also trying to reprogram adult stem cell in order for them to develop ES characteristics. They are called induced pluripotent stem cells (iPSC).

Stem cells can also be put in two categories depending on their ability for self-renewal (maintaining undifferentiated) or potency (ability to differentiate).

Animals stem cells can help the animal regenerate lost body parts but in humans it can only heal injuries. Human adult stem cells have less potential to differentiate than animal stem cells. Because of that scientist are trying to activate stem cells in human body and make them increase their potential to differentiate so they are able to make cells they were not able to make before.

Stem cells are being used in medicine for treating lots of diseases. One of them is sickle cell disease (SCD). It is an inheritable disease in which the hemoglobin in red blood cells is not functioning properly. Defective hemoglobin causes red blood cells to become stiff, sticky and sticky-shaped which causes vessel clothing and the transfer of oxygen to that part of the body as shown in picture 3, which later on causes severe pain, organ failure and even stroke. The only known treatment of this disease is through use of adult stem cells that are being transplanted through bone marrow. Donors bone marrow is being extracted to obtain stem cells which are then induced through blood into the infected patient. Stem cell slowly travel to bone marrow where they settle and start producing healthy red blood cells. The treatment success rate is 87 per cent by research conducted by National Institute of Health (NIH).
Another way to treat SCD is by usage of iPSC which is not allowed in most of the countries of the world because they still haven't been fully tested. 

Picture 3: Sickle Cell Disease

Every human has been created from stem cells. After sperm and egg meet they develop a kind of stem cell that has the potential to grow into a human being. First few divisions every stem cell has the same potential but as the process continues, but as the process continues cells loose that potential and start to differentiate. In the first week cells form a blastocyst (Picture 4). Blasocyst contains an outer lair (placenta) and an inner lair (cell mass). Extracted cell mass is used in treatments because those are undifferentiated stem cell which can form any type of cell.

Picture 4: Blastocyst

Ethical consideration of cell therapy regard destroying a potential human life. Even thou that it only has the POTENTIAL to become a human people argue that it is unethical because the embryo in that state has same right as any human being. Most countries are not allowing ES research because it is unethical. but some countries allow it because they believe that embryo in that state does not have the same rights as a human being. They are founding the research but demand consents from donors. I think that stem cell research should be founded in more countries because it can help in couring diseases. If people give consent scientist should be able to do research with their stem cells. Another ethical issue is that stem cell is dangerous for human life. At Stanford Medicine scientist have found that some cancer cells act as stem cell. Some say that cancer cells are uncontrolled stem cells. This makes stem cell transplant dangerous because it is indefinite if the stem cells in another person body will be controlled meaning they can become cancerous cells. Yes, it could be dangerous but sometimes it is peoples only way of treating certain diseases so i do not think it should rise an ethical consideration.

Stem Cells Matija

Stem Cells

The human body comprises over 200 different cell types that are organized into tissues and organs to provide all the functions required for viability and reproduction. One of these cells in the human body are called stem cells. Now one might ask, "what are stem cells?" Stem cells are multicellular organisms (undifferentiated) which are capable of changing into and arising other cells. More specifically, as news medical describes it as; “Stem cells are mother cells that have the potential to become any type of cell in the body.” (http://www.news-medical.net/health/What-are-Stem-Cells.aspx) Through early life, and growth stem cells are transformed and changed into many different cell types. This is because they serve as an internal repair system to countless of tissues inside the human body, dividing without any specific limit until they restore the other cells that were harmed or missing in that certain part of the body. Stem cells are very important, for as I mentioned above they can replenish certain organs, however they can also produce all the different cell types that make up our blood. Meaning that it can fight off unwanted diseases, through the use of blood transplants, restoring the diseased filled blood and returning to its normal state. Blood transplant is the most common use of therapeutic use of stem cells, more than 26,000 patients are treated with blood stem cells in Europe each year. Stem cells differ from other cells types because of two important characteristics; Firstly they are unspecialized cells and have the ability to renew themselves through cell division. Cell division is the process in which distribution of identical genetic material, DNA, splits into two cells, meaning that one cells splits identically into two whole cells.  You can see this clearly in the picture bellow.

Secondly, if needed they can be under experimental or physiologic conditions, where they are then stimulated to become tissue, organs, or any other specific cell with special functions. However stimulation cannot happen alone, to get the stimulation of the stem cells to change into a specific function a transplant has to occur. Although in some organs, such as the gut and bone marrow, stem cells regularly divide to repair. In other organs, however, such as the pancreas and the heart, stem cells only divide under special conditions. These are the two types of characteristics drawn simply to illustrate what I have stated

There are also two types of stem cells. The first one being embryonic stem cells (seen in the first picture): which are cells that developed from the embryo, mostly fertilized embryo cells. And second, adult stem, also known as Non embryonic stem cells (seen in second picture): are undifferentiated cells that multiply cell division.               

 Embryonic stem cells

 Adult stem cells

Due to their great regenerative qualities, stem cells are widely used for therapeutic purposes in order to cure and treat incurable diseases. One of therapeutic purposes of stem cells is to treat Parkston’s disease. This pluripotent, endlessly dividing cell has been hailed not only as a possible means for treating Parkinson's disease but also, diabetes, Alzheimer's, spinal cord injury, heart failure, and bone marrow failure. However, here we are focusing on the treatment of Parkinson’s through the use of stem cells. Parkinson’s disease is a lack of dopamine “– a chemical that allows messages to be sent to the parts of the brain that control movement and some forms of thinking.”  (http://www.eurostemcell.org)  The disease targets and kills dopamine-producing nerve cells, or neurons, in part of the brain called the substantia nigari, even though this disease does attack and affect other nerve cells in the brain, which may be used for some other tasks such as problems with sleep, motivation, thinking, etc. Although the main variable to the cause of Parkinson’s disease is still unknown, scientists do know which cells and areas of the brain get harmed. Researchers are already using stem cell to grow dopamine-producing nerve cells in a laboratory so that they can isolated and focus on the disease,  especially in cases where Parkinson’s is passed on through a known genetic cause.  Researchers are trying to figure out if there is a possibility of treating Parkinson’s by replacing a lost nerve cell with a healthy new one.

However, it goes without saying that stem cell research has been very controversial. There have been several ethic concerns and problems that follow this topic. Professional consent is needed to be written down and signed by all participants who are involved in any stem cell transplant.  As mentioned, embryonic stem cells are a major part in treating many stem cell related procedurs, and because of that, a lot of research has made the extracting of embryonic stem cells mandatory. However, in order to extract embryonic stem cells, the fertilized egg cell, which at this stage of growth is called blastocyst, has to be destroyed after 5-7 days of life. This is by many considered to be murder of a young living organism, which will later become a fetus. Religion also plays a big part in this controversial topic, because many believe that a blastocyst is still considered to be a human, since life begins at conception. Of course the other side of the coins states that this would not be considered to be living because it didn’t get to experience anything that makes us, living. Such as emotions, pain, memory and so on. This topic will continue to be a very controversial one, but people will need to see if the pros out weight the cons, since stem cell therapy is still one of the most effective ways to treat incurable diseases.

Stem Cell Elena

What Are Stem Cells?

Stem cells are a group of identical cells which develop and grow into different types of cells. According to Medical News Today, in most common situations, stem cells form from embryo's and adult tissue, which are also known for their potential to develop into different cells.

Embryonic Stem Cells 

Figure 1: Visual description of the development and function of an adult stem cell

"Embryonic stem cells are derived from a four- or five-day-old human embryo that is in the blastocyst phase of development."(source). Before the embryonic stem is produced, the fertilized egg, a zygote, starts to multiply it's cells. Once the group of cells is set in the uterus, it becomes a blastocyst. The blastocyst consists of an inner and outer mass. The outer mass, the trophoblast, then develops into the part of the placenta around the growing organism, while the inner mass, the embryoblast, develops into the organism itself. These cells from the inner mass that develop into a human body are embryonic stem cells, holding the potential to become a cell of any part of the human body (see Figure 1).

Adult Stem Cells


These types of cells are found in the body once developed from the embryonic state. Adult stem cells are found in different types of tissues, such as brain and skin. They hold their single form, without dividing, until acted upon a disease or injury. Adult stem cells have the ability to multiply and develop continuously, therefore allowing them to expand the range of cells in organs. 

The main function of these cells is to develop cells which are "damaged" by multiplying to replace them. The body's renovation is controlled by our adult stem cells. Here is a video of a man who suffered from unhealthy stem cells which were unable to fully maintain his health. He turned to stem cell transplantation, and lived through a miracle.

For more visuals and information about stem cells, click here.

Therapeutic Potential of Stem Cells

Figure 2: Visual representation of adult vs embryonic stem cells

The cells in our body all have a specific function. According to StemCellsThailand.org, stem cells, specifically, hold the function to renovate cells which have been damaged by disease or injury, therefore controlling out body's health. Adult stem cells and embryonic stem cells, both hold the function of repelling diseases such as ALS, Leukemia, diabetes, and infertility (see Figure 1). However, embryonic stem cells have developed into the cell from the organ it protects, whereas adult stem cells may develop into different cells. When looking at the therapeutic aspect of stem cells, adult stem cell are more practical and effective in controlling the body's health, due to their ability to transform into other cells, therefore raising the probability of repelling the disease. You can see the different ways of development, as well as functions in Figure 2.

Ethical Issues of Stem Cell Therapy

While our body contains countless stem cells, trying to maintain our body's health, in many cases the diseases are too powerful to be repelled. This all depends on the health of our body and how capable our stem cells are. In the video above, the man who's stem cells failed to maintain his health, turned to transplant therapy to remain his physical health. However, even with the perks of avoiding such diseases or lowering the effects, there are many ethical issues. According to StemCellres.com, other potential stem cells have been discovered, as well as the pursuing of the idea to artificially increase their potential within our body, raising ethical issues. Even if these newly discovered stem cell types have the power to control our body's health more than embryonic or adult stem cell, which naturally developed in our body, adds risk to the patient's long term health. In the aspect of embryonic stem cells, an embryo is at the stage of developing into a living being, where if therapy is used to artificially develop these cells, the risks of killing them may raise. Since embryos are becoming living, killing the cells, even if not intentionally, through therapy is considered unethical. 

Stem Cells

Stem Cells

Figure 1
This image shows stem cells and their possible
development into specialized cells.

Stem cells are a certain type of cells which have the potential and ability to develop into specialized cells of the body. This process is most productive during the early stages of life and growth.  These types of cells are called unspecialized cells because they do not have a set function. Stem cells have the capability to develop into any cell which the body needs to repair. Stem cells serve as a repair system in tissue and other internal systems. When reconstructing, they are able to divide without limit to restore other cells.

            There are two significant features that characterize stem cells. One of their characteristics is to be able to renew themselves through reproduction even after long terms of inactivity.  The second distinction is that they are able to become specialized cells, if a certain compartment needs repairing. For example, some stem cells become specialized into bone marrow cells in order to replace and restore damaged or worn out tissues.

A stem cell divides through asymmetrical division which means that the daughter cells have different cellular destinies. Stem cells replicate in this way so that one of the daughter cells has a copy of the original stem cell while the second daughter cell is programmed to potentially differentiate into a specialized cell. The cell which has the possible ability into becoming a specialized cell can contribute to the reparation of many different body cells such as the heart cells, muscle cells, blood cells, or nerve cells. However, sometimes the parent cell reproduces symmetrically, producing two daughter cells of identical DNA. 

Therapeutic Potential of Stem Cells

         Stem cells are very important in the development of organisms. The stem cells can help fix any damage to the tissues in the body by specifically specializing in the cell type needed. Stem cells are a renewable source and replacement for damaged cells which could treat serious diseases. Therefore, scientists have been researching for many years about the therapeutic potential of these cells. The tested therapeutic potential of these cells has been through the method of transplantation so far. This medicine field is called regenerative medicine.

            In a stem cell transplant, researchers specialize the embryonic stem cell (stem cells derived from the early stage of the embryo) into the necessary adult cells. The adult cells or ‘mature’ cells, through transplantation, are then replaced by the damaged tissue which was caused by a disease or injury.

At this point, in this area of medicine and biology, researchers have approved of very few medical uses of stem cells. One of the approved methods is the bone marrow transplantation. This treatment is used for treating blood and other disorders in the immune system. This treatment is a medical procedure of damaged or diseased bone marrow, replaced by specialized stem cells which develop into healthy bone marrow cells.

Figure 2
The process of stem cell usage to develop drugs.

Even though, only a few treatments have been medically approved, scientists are still working on the usage of stem cells and how they can be beneficial to our health. The stem cells are used to study diseases and identification of new drugs and their side effects. This is a developing impact on the human health and technology where transplanting cells is not needed. Scientists are using stem cells to test new drugs. The stem cells are used indirectly meaning that they are being tested on instead of used in the actual products (drugs). Scientists control the differentiation of stem cells to fit them into specific cell types which drugs will be tested on. Depending on how the stem cells react, the scientist will know the validity of the 

Ethical Consideration

Figure 3
Generating stem cells from an embryo.

        Ethical considerations and discussions have always played a big role in this specific part of medicine and research. Countless ethical discussions have taken place over the subject of embryo stem cell usage.  The embryo is formed from a sperm cell and an egg cell, making the egg fertilized. Embryo's are the first step to the growth and development of an organism after the cell egg has been fertilized. Many people may argue that the embryo has a potential of becoming or is a living person and should not be killed or used for purposes like these. Those who claim this, believe that the embryo will become a person and therefore should be give the respect and dignity of a person. However, others argue that an embryo (collection of cells developed from a fertilized egg) which has not been implanted into a woman's uterus, will not have the physical nor emotional properties of a human. And therefore, there is no concern in preserving the embryos since they will be used to aid patience, who are people as well. The following statement, was said by the well known scientist, Stephen Hawking, "Stem cell research is the key to developing cures for degenerative conditions like Parkinson's and motor neuron disease from which I and many others suffer. The fact that the cells may come from embryos is not an objection, because the embryos are going to die anyway." 

Stem Cell Blog- Yoonsik Park (Oct,5th, 2015)

Yoonsik Park
1. What Are Stem Cells?

         According to the IB-guides website, they are cells that have not been fully differentiated, however, they have the ability to divide and differentiate into different types of cells. For example, a stem cell can differentiate into a brain cell, or a blood cell. As you can see in (picture 1), a stem cell can duplicate itself or differentiate into many cell types. They are necessary in embryonic development because all of the cells in an adult organism come from stem cells. 

 (http://ibguides.com/biology-2016/notes/stem-cells)

   

(Picture 1)    http://nas-sites.org/stemcells/files/2013/01/What-Is-Download.jpg

Development of embryonic stem cells:  A zygote is formed when an egg cell from the female and a sperm cell from the male fuse. The zygote then divides into a two celled embryo. That embryo will keep dividing into a 4 celled, 8 celled and so on. In the early stages of development, the embryo cells are stem cells because they have the potential to become any type of cell. As the embryo cells divide, they eventually start to be committed to a specific path. (For example, as you can see in picture 2, some cells will become committed to liver cells, nerve cells, cardiac cells, blood cells, or something else)

At this point, although they still have the ability to differentiate, they can only differentiate into the type of cells that they are committed to. (For example, if an embryo cell is committed to a kidney cell, they can only differentiate into that, not liver or blood cells.) So they are no longer stem cells, but they are uni-potent.

(Picture 2) http://www.extremetech.com/wp-content/uploads/2014/07/stem-cells.jpg

Adult Stem Cells: There are still some stem cells in an adult organism. (Can be found in the skin, bone marrow, and liver) They are able to differentiate into different cells but not as much as the embryonic stem cells. So they are not as effective. However, they still benefit adult organisms greatly by regenerating and repairing damaged tissues.

 (http://ibguides.com/biology-2016/notes/stem-cells)

2. Therapeutic Potential of Stem Cells

Since stem cells can differentiate many times and into different cells, they are the best for therapeutic use in degenerative disease or tissue repair.
Therapeutic : "The branch of medicine that is concerned specially with the treatment of disease."             (http://www.medicinenet.com/script/main/art.asp?articlekey=18811) 

One example of therapeutic potential of stem cells-
Umbilical Cord Blood Stem Cells: 

(Picture 3) https://upload.wikimedia.org/wikipedia/commons/f/f3/Umbilicalcord.jpg

 As you can see  in (picture 3), the  umbilical cord is  no longer needed  to the survival of  the baby or the  mother when the  baby is born. So  it is usually  thrown away  after the baby is  born and is cut  off from the baby  and the mother's  body. However, it  has been discovered recently that the blood, rich of stem  cells, from the umbilical cord can also be used to treat  problems that are treated by bone marrow stem cells and  peripheral blood stem cells.
 Umbilical cord blood stem cell transplants have a  lower possibility of rejection than other blood stem cells. This  is believed to be because they are not as developed yet,  which means that there are not as many immune cells; it is  less possible that the cells will react badly in the transplant  recipient's body. Because umbilical cord blood stem cells are  capable of adapting easily, and are available very much, it  makes them a potential resource for therapeutics.

      (http://learn.genetics.utah.edu/content/stemcells/sctoday/)

 3. Ethical Considerations of Stem Cell Therapy

Using stem cells to treat diseases and tissue repairs is very helpful in many ways. However, there has been some controversy over the studying, using, and destroying of human embryos for research and therapy using embryonic stem cells. 

(Against embryonic stem cell therapy) Since the embryo is the result of the sperm and egg fusing and developing, many people consider destroying human embryos after the research or extraction of stem cells as unethical. As you can see in picture 4, since extracting the stem cells destroys them from developing further, they consider it murder; the embryos have the potential become new babies.

(Picture 4) - http://federation-pro-europa-christiana.org/wordpress/wp-content/uploads/2011/12/Stem-cell-research.jpg

(For embryonic stem cell therapy) However, there are those who argue for embryonic stem cell research. One of their main arguments is that the embryo is only a few cells clumped together, so it cannot be considered as life yet. "It cannot survive outside the womb on its own so it cannot be considered life." Secondly, they claim that the research being done will benefit humans widely so it is justifiable. Also, according to the PubMed Central website, embryos that are used in research are donated by the woman or the couple.
(http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2726839/)