These are immature stem cells which have been collected from both the umbilical cord and the placenta after the birth a baby.  Each cord contains approximately 150,000 stem cells.  While termed Adult stem cells they are in fact very immature stem cells and considered in the life span of a stem cell to be among the “youngest” type of stem cell available.  Umbilical stem cells are widely used in medical treatment in part because they are much less likely to result in graft-versus-host disease (GVHD).

The common defining properties of an adult stem cell are two fold.  First it must have the ability of self renewal.  This is defined as the ability to multiple over and over again while maintaining its original state of undifferentiation.  The second requirement is multipotency also know as mutltidifferentiative potential.  In essence the stem cell must be able to eventually generate several different cell types.

It should be noted that much of the research involving adult stem cells has focused on controlling the differentiation process.  If one can discover and unlock the molecular mechanisms that control this process one can then effectively guide the cell into developing a specifically desired cell type.  Of particular interest is the Notch pathway.  It has been known to scientists for years and has been proven to produce cells types such as hematopoietic, neural and mammary stem cells from adult stem cells derived from umbilical cord and placental blood.

Understanding such pathways becomes essential when attempting to modify a stem cell.  Modification is determined in part by the plasticity of the cell also known as transdifferentiation.  This type of differentiation can be induced and guided by making changes to the growth medium in which the stem cells are cultured.  Knowing and understanding the molecular mechanisms and pathways of stem cell differentiation has allowed scientists the ability to exert some control over the stem cell.  It could be described as giving the stem cell a nudge in a certain direction such as the propensity to become a neural cell.  It has been shown that given the proper circumstances neurogenesis, the birth of new neurons, can be induced in various regions of the brain and central nervous system.

It is this knowledge that spurs on so many researchers and the medical community at large.  It is this understanding that gives hope to those with brain and spinal cord injuries.  While standard treatment protocols for such are far from being realized in western countries such as the Untied States and Canada demand has given rise to the availability of stem cell treatments else where.  For those willing to enter the door to this new frontier has been opened.

Written by Kirshner Ross-Vaden RN

October, 2006

A historical footnote: Neural stem cells were first cultured in vitro as neurospheres in 1992

The Who’s Who Spot Light:  

Yongzhi Ding is known to many of her patients simply by her chosen English name of Debbie.  She graduated from Beihua University with a Bachelors Degree in Nursing as well as English study.  Debbie in fact received very high marks in the National Chinese English Exams.  She has been with the inpatient stem cell program at Nan Shan Hospital in Shenzhen since it opened a few years ago.

We asked Debbie about her personal experiences and thoughts about working with stem cell treatments and patients and here are her words;

Stem cell treatments are still a new area with new techniques.  When I began working in this area it was a very big challenge for me both in technique and the language.  We began training for the theory and operational skills in October 2005.  Our hospital also puts an emphasis on the study of English because most of our patients speak English.  It’s very important for us to be able to communicate with them during our work.  I have worked with stem cell patients from the first day that our department came into being.  I look at every patient as my relative and I feel happy when I see their improvements.  So far there have been around 100 patients that have come here to receive stem cell treatments, which has included some as old as 80 and others that are only babies just a few months old.  They come here with hope and go home with a sense of satisfaction. Some of them completely paralyzed leave being able to turn over smoothly; some who come can not speak but soon they begin to speak in little bit of words which they could not pronounce before they arrived; some of them develop the ability to control their stool and urine which had been to them years before…… It’s amazing that our science is so developed and advanced. You will take it for a surprise if you aren’t familiar with the results of stem cell treatments.  We really need to say thanks to those hardworking people who cultivate the stem cells. They bring health and smiles to our patients and I pledge to try my best to give my strength and warm to those patients still in dark.

Recent Research:

Stem cells: Chemistry paves way toward promising therapies

SAN FRANCISCO, Sept. 14 -- Chemists are developing new insights and techniques in an effort to expand the therapeutic potential of stem cells, which includes possible treatments for Parkinson's disease, diabetes, spinal cord injury and other devastating conditions. The American Chemical Society will explore some of these latest developments, including new findings on the transformation potential of adult stem cells, during a special symposium, "Emerging Technologies: Stem Cells," being held in San Francisco.

A key event in stem cell research:  in the 1960’s Joseph Altman and Gopal Das presented clear evidence that neurogenesis is not finate but rather is an ongoing process within the brain.  Their report was largely ignored as it was in direct conflict with the already accepted dogma of Cajal’s “no new neuron’s” theory.  We now know today that it can indeed  be an invoked and possibly ongoing process.

Terminology to Know:

Adult (or somatic) stem cell—An undifferentiated cell found in tissue that can renew itself and differentiate (with certain limitations) to give rise to all the specialized cell types of the tissue from which it originated.  Rise to cell types other than those of the tissue from which they originate. 
                                                                                      
Blastocyst—A preimplantation embryo of about 150 cells produced by cell division following fertilization.
                                                                                              
Culture medium—The liquid that covers cells in a culture dish and contains nutrients to feed the cells.  
                                                                                     
Differentiation—The process whereby an undifferentiated embryonic cell acquires the features of a specialized cell such as a heart, liver, or muscle cell.           
                                         
Multipotent—Ability of a single stem cell to develop into more than one cell type of the body. 
                                                                                                                  
Pluripotent—Ability of a single stem cell to give rise to all of the various cell types that make up the body.
                                                                   
Surface markers—Proteins on the outside surface of a cell that are unique to certain cell types, which are visualized using antibodies or other detection methods. 
                                                                                 
Undifferentiated—A cell that has not yet generated structures or manufactured proteins characteristic of a specialized cell type.

Q & A:

Is it true that umbilical cord derived stem cells have a genetic finger print and this leads to rejection issues?
 
No, this is not true.  References made to "DNA" and/or "fingerprints” does not apply to this type of stem cell. It isn't DNA variations per se, but surface antigens, often referred to as "markers", that signal "self" from "other".  "Self" being the bodies own matter and "other" being a foreign substance.  The consensus of studies published in scientific literature is that human umbilical cord stem cells (hUCSCs) provoke little in the way of adverse reactions due to antigenic recognition by the recipient. Meaning that they lack markers and the body sees them as "self". This is why anti-rejection medication is not needed when doing a SCT with hUCSCs.
 
What are the sources of stem cells?
 
There are three sources of stem cells:
 
Embryonic stem cells (ESCs) are derived from 4- to 5-day-old embryos. At this stage the embryos are spherical and are known as blastocysts.

Each blastocyst consists of 50 to 150 cells and includes three structures: an outer layer of cells, a fluid-filled cavity, and a group of about 30 pluripotent cells at one end of the cavity. This latter group of cells, called the inner cell mass, forms all the cells of the body.  ESC cultures are created in the laboratory by transferring the inner cell mass from a blastocyst into a specially treated plastic culture dish. The cells divide and after several days begin to crowd the culture dish. When this occurs the cells are removed and transferred into several fresh media dishes and/or bags. This process is repeated many times and eventually yields millions of ESCs.

One possible drawback to using differentiated ESC lines in stem cell therapies is that the ESCs might illicit an immune response when placed into the patient, because the protein markers on the ESC surfaces might be viewed as foreign by the recipient’s immune system.
 
Adult stem cells are undifferentiated cells that are found in small numbers in most adult tissues and have also been found in children.  A more accurate phrase for this is “somatic stem cells,” although this phrase has yet to be generally adopted. The primary roles of adult stem cells in the body are to maintain and repair the tissues in which they are found. They are usually thought of as multipotent cells, giving rise to a closely related family of cells within the tissue. An example is hematopoietic stem cells, which form all the various cells in the blood. Recent evidence however indicates that some adult stem cell types may be pluripotent, or at least able to differentiate into multiple cell types. For example; hematopoietic stem cells can differentiate into neurons, glia, skeletal muscle cells, heart muscle cells, and liver cells. Whether they actually do this ordinarily within the body is unknown. A potential advantage of using adult stem cells from a patient is that the patient’s own cells could be expanded in culture, treated to differentiate into the desired cells, and then reintroduced into the patient. The use of the patient’s own cells would eliminate any possibility that they might be rejected by the immune system. Disadvantages of using the patients own adult stem cells are that they are rare in mature tissues and it is more difficult to expand their numbers in cell culture, compared with ESCs.

Adult Stem Cells can also be extracted from the placenta and the umbilical cord.  Blood from the placenta and umbilical cord is a rich source of hematopoietic stem cells. These so-called umbilical cord stem cells have been shown to be able to differentiate into bone cells
and neurons, as well as the cells lining the inside of blood vessels among other types of cells.  The greatest advantage to this type of stem cell being used in a transplant is that the recipients own immune system is highly likely to recognize these cells as “self” since they have no markers on their surface.
 
Fetal stem cells also known as germ cells are pluripotent stem cells derived from so-called primordial germ cells, which are the cells that give rise to the gametes (sperm and eggs) in adults. Scientists obtain primordial germ cells from the area in a fetus destined to become either the testicles or the ovaries (the dividing line between embryo and fetus is the end of the 8th week). They also have been obtaining neuronal cells from the brain and spinal column of the fetus.  Like ESCs, the primordial germ cells are transferred into a specially treated plastic culture dish, where they form germ cell colonies.

Less research has been performed using embryonic germ (EG) cells than ESCs, mostly because the embryos used for deriving EG cells are deliberately aborted, while the blastocysts used for deriving ESCs are produced through in vitro fertilization in a fertility clinic. EG
cells are also difficult to maintain in cell culture because they have a tendency to differentiate spontaneously.
 
Provoking words for the mind:

One thing can't be doubted, the "possibility of a quality" is within us.  It is called Prajana.  We can deny everything, except that we have the possibility of being better.  Simply reflect on that.

Insight >From the Dalai Lama

Lights on the Horizon: 

Nanotubes(September 22, 2006)

Nanotube Scaffolds for Neural Implants

Tiny carbon fibers are helping stem cells to grow in stroke-damaged brains.

The following are excerpts taken form an article By Jennifer Chu.

“Stem cells are a promising therapy for stroke and other brain

Injuries, they can sprout into healthy neurons and may be able to re-establish brain activity in brain-injured patients.”  

Thomas Webster, associate professor of engineering at Brown University states “What's needed is an ‘anchor’ to keep stem cells fixed to the damaged areas, where they can then differentiate into working neurons.”

“Webster and his collaborators in South Korea found a possible anchor in carbon nanotubes: tiny, highly conductive carbon fibers that not only act as scaffolds, helping stem cells stay rooted to diseased areas, but also seem to play an active role in turning stem cells into neurons.”

“Just how this works isn't clear, but the researchers say their

initial results could someday be engineered into a stem cell delivery device for stroke therapy.  Webster presented the team's findings at the American Chemical Society meeting this month in San Francisco.