The very mention of the words “stem cell” perk up everyone’s ears. Although this topic is so controversial and exciting, do most people understand what stem cells are? This is a basic guide to stem cells with all the definitions, abbreviations, and applications you need to know to carry on a conversation about stem cell development, research, or controversy.

Cells - The Basic Unit of Life
Starting from the beginning, cells are the basic unit of all life. They contain DNA (deoxribonucleaic acid), which is all of the cell’s genetic material. They also have the ability to undergo cell division and replication, which creates two daughter cells with identical DNA. There are somatic cells and germline cells. Somatic cells make up every part of your body from your eyes, to your skin, to your heart. Somatic cells are also the type of cells that cancer research uses and the types of cells that were used in Dolly, the sheep clone. Germline cells are sex cells that are used in sexual reproduction with females and males carying different types. When a female germline cell (ova) and a male germline cell (spermatazoa) combine during sexual reproduction, they form a zygote. The zygote then goes through several divisions (showed below) to form into a ball of pluripotent cells called stem cells.

Enter Stem Cells…
The yellow cells in the figure above are pluripotent stem cells, which means these cells have much potential to differentiate into any type of somatic cell in the body. Differentiation is a developmental process by which unguided cells “turn into” a specific somatic cell type, like a blood cell or a nerve cell. During embryonic development, the perfect amounts of stem cells differentiate into every type of tissue to create all of the wonderful organs in our body as demonstrated below. While healthy (non-cancerous) cells in the body go through only about 50 replication cycles and then naturally kill themselves (to prevent excessive genetic mutations), stem cell have the capacity to theoretically divide forever. They can go on through millions and billions of cycles developing new cells with no limit, if supplied with the proper environment.

Types of Stem Cells
There are three main types of stem cells which are all obtained differently, have diverse applications, and face various controversies.

Embryonic Stem (ES) Cells can be obtained from the early developing stages of an embryo as shown in the first figure with a blastocyst. Stem cells obtained from this newly developed bundle of cells have the full potential to differentiate into absolutely, positively anything in the human body. Many scientists believe that embryonic stem cell research could lead to therapies that have the potential to cure at least 120 million Americans. They believe that these cells have the potential to cure thousands of disorders and biomedical problems such as Parkinson’s Disease, Alzheimer’s Disease, spinal cord injury, and organ replacements. These are the types of stem cells that are under constant controversy because they are taken from a five to six day old embryo . President Bush has legalized approximately 60 genetically diverse stem cell lines that can legally be used in research laboratories in the United States. The constant struggle between science, the government, and religion is at the pinnacle of this controversy.

Adult Stem Cells can be obtained from full-grown adults, but not all of their cells are stem cells because the majority of them have already differentiated. Therefore stem cells have to be found in special parts of the body where they have been saved and undifferentiated, like in bone marrow or early stages of tissue development. These cells are not fully pluripotent and (so far) have only been able to differentiate into a limited number of tissues. However they have been used for various applications such as cloning, trying to cure diabetes, and artificial blood. A major controversy in adult stem cell research has been cloning and the effects of cloning. The biggest question that is pending is how far people will go with cloning as fears rise such as in the book Brave New World and the movie The Island. Cloning is limited to animal use only and it is strictly and absolutely unlawful to apply to human use…for now.

Umbilical Cord Stem Cells can be obtained from the umbilical cord of a new born baby. Millions of multipotent (not as much potential as pluripotent, but more potential than differentiated cells) stem cells lie in the umbilical cord and the blood in it. These stem cells can be saved in a stem cell bank and later used for bone marrow, anemia, and cancer treatments. There is not much wide-spread controversy in these types of stem cells because the umbilical cord is usually thrown away after child birth. Therefore this stem cell bank idea utilizes trash and turns it into a potential life saver.

More information on stem cells can be obtained from National Institutes of Health, The White House’s Stem Cell Fact Sheet, TIME/CNN, and The University of California, Irvine.
-Amy Shah

There’s so much going on in the world of science, unfortunately I can not cover it all. Here’s the latest buzz going around in the field.

Alzheimer’s Disease Cure on the Way
Purdue University has discovered the first step in a cascade of events leading to amyloid plaque formation in the brain. This is the beginning of finding a cure to Alzheimer’s Disease. A vital enzyme, called memapsin 2, was discovered to be what seems like the cause of plaque formation in the brain. Further research into this area delves into creating a memapsin 2 inhibitor protein to block the function of the enzyme before it causes plaque to build up.

Immune System Activation
Scientists at the University of Michigan have discovered a bacteria that inserts itself into the body and evokes a strong immune response. These bacteria attach onto receptors on the surface of immune cells and hyperactivate them. Think of the possibilities for victims with weak immune systems and post-traumatic surgery patients!

Dr. Heart Robot
HeartLander, a 20 millimeter long robot, has been invented to deliver drugs to the heart in a minimally invasive manner. Surgeons can monitor this robot’s crawling motion across a beating heart with an X-ray video and control its movement by using a joystick. Scientists are continuously developing this robot to become more eclectic so that they may be able to utilize it for the treatment of a plethora of heart conditions.

Type 1 diabetes is an illness in which the body’s immune system kills off insulin produced naturally in the body. As a result, victims of type 1 diabetes have to administer regular insulin shots to themselves in order to control their blood-sugar levels. This affects over 340,000 people in the United States alone!

Imagine changing those hundreds of thousands of peoples everyday lives. Scientists have conducted a risky trial and successfully injected stem cells into 15 patients with type 1 diabetes. Thirteen of the 15 patients have ditched their insulin shots and can have been able to live healthy lives ever since the treatment!

Alternative treatments are also still in the testing phase, however this treatment has the potential to be the cure to diabetes because it’s has undergone Phase III research. This treatment’s problem is the wide opposition to stem cell research (like President Bush) that will push it back for an indefinite amount of time. This cure could change the life of 1 in every 800 people with type 1 diabetes, support stem cell research because its potential could soon change your life.

John Hopkins University is the top biomedical engineering university in the entire nation. Their Urology Robotics lab has successfully built a robot out of plastic, ceramics, and rubber that is powered by light and air; therefore it can function during an MRI (magnetic resonance image) scan without disrupting the reading or breaking down. This robot can precisely remove an organ biopsy while the patient is in the MRI machine. This is important because it can improve the treatment of prostate cancer since prostate cancerous cells are extremely difficult to see outside of the MRI scan. This means that surgeons won’t have to perform a blind cut surgery on the patient.

WOW! No metal. No electronics.

-Amy Shah

The silicone chip below functions just like a live brain cell and can communicate with other brain cells as well, thereore we may be calling it an artificial neuron in the near future. At the University of Southern California Center for Neural Engineering, scientists have created the beginning of an amazing device whose final goal is to revive Alzheimer and brain trauma patients’ memories. Design engineer Vijay Srinivasan can demonstrate how this tiny silicone chip can send impulses down a wire to brain cells. The signals between the chip and a brain cell are almost identical to signals between two communicating brain cells!

Dr. Ted Berger is the big brains behind this idea and he believes that this chip’s ability to communicate with live brain cells is the first step to a fully implantable machine that can possibly one day replace the entire brain. This is a long way down the road and sounds like turning humans into robots, but it is definitely a major breakthrough in human-computer interfaces.

-Amy Shah

There’s so much going on in the world of science, unfortunately I can not cover it all. Here’s the latest buzz going around in the field.

Stem Cells
Scientists in the UK have developed an artificial heart valve grown from stem cells. Artificial heart valves are usually made from bovine materials, plastic, or metal alloys, however immune rejection of foreign materials in the body becomes a huge problem that can lead to heart disorders. These stem cell heart valves have the potential to prevent risk of endocarditis and stenosis because they act just like natural heart valves.

Nanotechnology
Purdue’s Brick nanotechnology center is utilizing nanopore channels to distinguish specific sequences of DNA. They created channels with diameters between ten and twenty nanometers in silicone and attached a single strand of DNA to each channel. As liquid containing DNA translocates through the nanopores due to a generated voltage difference across the channel, they can differentiate between certain DNA molecules.

Nicotine and Memory
Nicotine has the ability to cross the blood-brain barrier and activates reward pathways in the brain that trigger feelings of euphoria and satisfaction; this is what makes it so addictive. Dutch scientists have taken advantage of this powerful property of nicotine and discovered how it affects memory in the brain. Nicotine influences neural wiring to enhance memory by strengthening the connections between neurons when the brain is accessing memory.

-Amy Shah