What are Stem Cells?

Intro-

In the study of medicine, doctors and scientist are constantly researching new methods, and testing different approaches to cure diseases. Embryonic stem (ES) cells and adult stem cells are a part of this new research and stimulate a new way of scientific thinking. ES cells and adult stem cells are commonly studied due to their promising potential to change the world of medicine. These unique cells have the potential to change their form and function to act as another type of cell. Scientist have formed and performed experiments to test the ES and adult stem cell’s abilities to transform into other organism when put to real life situations, such as cancer and diabetes. Along with complex science of these cells comes controversy. The research of the ES and adult stem cells controversy is based upon politics/government budget, and moral/ ethical views. Despite, being faced with political and ethical adversity stem cell research is still very prevalent.

Stem cells are “the body’s master cell” they are very important to the body’s organs (Jha, 2011, [5]) .These cells have several abilities that can be used to rebuild damaged cells (Jha, 2011, [1]). Multiple stem cells form a line and they are called a 'line' of stem cells. Stem cells are able to replicate themselves infinitely and change their structure and form into a number of different types of cells. Stem cells are unique because they are able to "fool' the immune system, unlike the common cells that can be marked as 'foreign' and rejected by the immune system, (Blackwell, 2009, [2]). The cells can be activated by certain substances that stimulate them such as Mesp1, once they are stimulated they replicate (Linsley RC, 2008, [3]).

Embryonic stem cells are a type of stem cell that are found in an embryo. ES cells consist of tiny, frozen clusters containing dozens of cells that can be obtained from fertility treatments (Knoepfler, 2011 [8]). ES cells are able to transform into different cells because the cells which they are formed by, are interchanging precursors for a number of different cells, this interchangeability gives the cells several descriptions(Canham, 2010 [1]). ES cells can be transformed into placenta cells that surround an embryo (Canham, 2010 [4]). ES may replace or repair damaged cells (Rodin, 2011 [2]).ES constantly express telomerase unlike normal cells. Telomerase is an enzyme that consist of RNA/ hTR, a protein/hTERT and additional proteins.Telomerase acts as an molecular clock for a cell, the clock can be turned back by coming in contact with normal cells. By reversing the 'clock' a cell's functional life is prolonged. Through the constant expression of telomerase embryonic stem cells are able to live a long life and restore genetic material (Geron#2,2011, [1]. ES cells are in some cases obtained for research from certain IVF(in-vitro fertilization) treatment patients (The Times,2009, [2]). It may take a dozen of human embryos to create just one 'line' of ES cells (The Times, 2009, [2]). Animal ES cells were first captivated in 1981 by Sir Martin Evans, human ES cells were first captivated in 1988 by Jamie Thomson and his team. There are multiple descriptions and functions of embryonic stem cells that frequently intrigue scientist. Due to the many functions of stem cells, these cells can be put to use in several ways and in different methods.Embryonic stem cells use their ability to replicate quickly and "fool' the immune system to express their pluripotency. Pluripotency is the ability for an organism to change into something else other than itself. 

One example of embryonic stem cells being used in medicine today is the Geron therapy. The Geron
Corporation was founded in 1990 by a man named Dr. Michael D. West. The company is a very popular medically leading company. It is a biotechnology company that specializes in stem cell therapies along with cancer therapies and telomerase activation (Wikipedia, 2011, [3,4]. The Geron Corporation obtains embryonic stem cells from IVF (in vitro fertilization) patients. The ES cells are used to create OPCs (oligodendrocyte precursor cells). OPCs are then used to treat spinal injuries. OPCs encourage nerve cell growth and secrete myelin (The Times, 2009, [4]).The myelin sheath is a layer of proteins and lipids that surround the brain and spinal cord nerves. Without myelin, nerve cells do not work as effectively, and that causes human impulses to be slowed down (Dugdale, 2009, [1]).

Researchers at Washington University School of Medicine use animal embryonic stem cells to try to treat Heart disease (Lindsley RC,2008, [1]) .The researchers used a stimulant to activate the animal ES cells to begin transformation into heart components. The stimulant is called Mesp1 and the animal that the embryonic stem cells were obtained from is a mouse (Lindsley RC, 2008, [2]). The process of transformation is a chain reaction (Lindsley RC, 2008, [3]). Mesp1 helps create an embryonic cell layer called mesoderm, that develops into the heart, blood, and other tissues (Lindsley RC, 2008, [5]). Once embryonic stem cells come in contact with Mesp1 they become either endothelial cells, smooth muscle cells, or cardiac cells (Lindsley RC, 2008, [6]). Researchers continue to test possible embryonic stem cell stimulants.

Wiley-Blackwell reports that Dr.Liu and Dr. Li of China researched ideas concerning stem cells in 2009. The doctors have discovered that human stem cells are able to create a vaccination for colon cancer. This discovery was found through experimentation and is based upon an old theory that " immunizing with embryonic materials may generate an anti-tumour response" (Blackwell, 2009, [1]). The stem cells are used to 'fool' the immune system into thinking that cancer is within the body. The body's reaction to the supposed 'cancerous' cells is to form a tumour-combating immune program (Blackwell, 2009, [2]). The researchers tested this experiment with Dr. Xu of the University of Connecticut, the team used mice. They observed that the mice's immune system fought harder against tumor formation, with the human embryonic cells present.

University of Michigan professors J. Lahann and G. Smith created a stem-cell growth matrix that is completely synthetic (Villa-Diaz, 2010, [2]). Many other scientist have cultured (produced) stem cell lines, but have not been able to put them into commercial production, because they were not FDA (Food and Drug Administration) approved.The FDA did not approve those cultured stem cell lines because they were grown on "animal based substances", animal based substances are substances/chemicals derived from animals that still contain some sort of animal gene(Villa-Daiz, 2010, [1]). J.Lahann and G. Smith have taken down a troublesome barrier by creating this synthetic matrix. Before Lahann and Smith's discovery, mouse embryonic fibroblast cells and Matrigel acted as stem cell matrices (Villa-Diaz, 2010, [3]). The animal based substances not only raised issues with the FDA, but also created problems for scientist. The animal genes in the substances were influencing the stem cells. The stem cells then, became unrecognizable because of the 'batch-to-batch' versatility, meaning the genetic material was altered each time it was exposed to the animal genes (Villa-Diaz, 2010, [5]). In order to create a synthetic matrix, the reseachers used a water-soluble gel abbreviated PMEDSAH (Villa-Diaz, 2010, [6]). Now with the new matrix the stem cell's normal genetic material and pluripotency remain a constant (Villa-Diaz, 2010, [8]). This new matrix helps promote stem cell use in medicine to treat several diseases.

Another matrix for stem-cell growth is laminin-511. This matrix was created by Karl Tryggvason from the Karonliska Instituet (Rodin, 2010, [6]).This matrix contains no substances from animals and does not need the help of any other cell to produce stem cells. The matrix is of a human protein,Laminim-511 (Rodin, 2010, [3]). Because the matrix is a protein, the whole production  can be directed and observed in a science lab. Scientist now will be able to manipulate the stem cells however and according to specific diseases (Rodin,2010, [4]). Laminin "is a part of our connective tissue and acts in the body as a matrix to which cells can attach". The protein keeps the stem cell's genetic material the same inside, the embryo. There are several types of laminin as well as several types of embryonic tissue (Rodin, 2010, [5]). The different types of laminin are created through recombinant techniques in gene technology (Rodin, 2010, [6]).

In addition to all the methods and new matrices listed above, there are still numerous findings revolving around stem cell research. Krista Conger from Stanford University Medical Center has reported that Dr. Wu, profesor of Cardiovascular Medicine and of Radiology at Stanford University, has found a new way for stem cells to be helpful in human cell or organ transplants (Conger, 2011, [2]). Wu was looking for a way to transplant cells without using immunosuppressants. Immunosuppresants are used to prevent a cell from being rejected during a transplant. The down-sides of using immunosuppresants are high blood pressure, increased weight, infliction upon the internal organs, and possible infection (Conger, 2011, [5]). Wu and his team (consisted of a graduate student named Jeremy Pearl) started with a new approach, they directed their focus on the relationship between a immune system cell, called a T cell and the stem cell that is trying to be transplanted (Conger, 2011, [6]). T cells are in charge of marking any foreign trespasser for destruction. Wu and his team used 'co-stimulatory receptor blocking agents', these agents are responsible for mediation between the stem and T cells. The co-stimulatory receptor blocking agents give T cells a tolerance for the stem cells (Conger, 2011, [6]). Pearl and Wu continue to test these agents to see what other situations they can be applied to. 

Stem cell research is also very impactful in the field of war zone medicine. Researcher Paul Knoepfler, in Sacremento at UC Davis School of Medicine is a serious advocate for stem cell research being put to use on the battlefield (Knoepfler, 2011,[1]). Embryonic stem cells can be used to produce different types of blood cells, that create several blood types for several soliders for a blood transfusion. Without embryonic stem cells the doctors and nurses must track down and obtain blood from a willing donor which may be time consuming, and in situations where a solider doesnt have time to spare, he/she may die (Knoepfler, 2010, [3]). Stem cells also can be used to repair bone and cartilage damage in a war veteran (Knoepfler, 2011,[6]), and repair skin damage on a burned solider (Knoepfler, 2011, [5]).Many more studies are underway. Athough the expectations of these stem cells are monumental they face some troubles due to budget. This baffling researcher comes at a price.

Due to a high budget needed to complete all of these stem cell involving practices, politics are often brought into this research. These politics sometimes thwart stem cell research. Starting in 2001 President Bush banned the federal funding of stem cell research, but private funding was still acceptable (The Times, 2009, [3]). Thomas Okarma, CEO of the Geron Company (a very popular company that specializes in stem cell therapies) was called to testify in the federal court case in 2001 revolving around cloning and stem cells (Wikipedia, 2011, [2]). In 2010, President Obama lifted the ban, but then in another federal court ruling, everything went back to the way it was before(Jha, 2011, [7]). Many scientist are annoyed and upset by the politcs that are involved with the cells .Once the media was included into the mix, the stem cells have received some negative attention due to misunderstandings and ethical issues. As of right now stem cell research is very prevalent and active, but still controversial. 

An example of stem cell research still being controversial would be the ethics of using embryonic stem cells. At one time using embryonic stem cells required the human embryo to be destroyed. Now destroying the human embryo to get the cell is not the only option, scientist can use certain materials to extract the cell. Those specific materials are what are so very expensive. Extracting stem cells from embryos is a very difficult process (Jha, 2011, [2 ]). The is destruction of embryos is controversial to those who believe that an embryo is just as precious as any adult life. Scientist are now conducting experiments to try to overcome these ethical isues by creating cells that can function similar to embryonic stem cells.

Conclusion-
Along with all difficulties that come with stem cell research also come the many rewards. Mesmerizing scientist and researchers every day with new and exciting techniques to be put to use, stem cells create an endless line of possiblities in the world of medicine. If used correctly and carefully stem cells can overcome almost any obstacles from blood transfusions to treating cancers.  Human embryonic and adult cells are the building blocks for creating more and more pluripotent cells. To conclude, the expectations and abilities of stem cells are constantly making way for a future of medical possibilty and achievement.  

-Glynda Tucker