Stem Cells

The best way to understand how stem cell therapy works is to explain what stem cells are.

Stem cells begin as unspecialized cells but are able to divide and renew themselves. Stem cells have

the ability to become specialized cells (differentiate) and work with tissue and organs. There are two

basic types of stem cells: embryonic cells and adult stem cells. Embryonic cells come from embryos

usually created through in vitro fertilization and donated, they have the ability to regenerate and repair;

they can continue to create cells for a year and sometimes more. Adult stem cells, also known as

somatic cells are body cells, not including gametes (egg or sperm); they do not have the ability to

proliferate for any extended period of time and generate cells of tissues in which they are located. Adult

stem cells are used to “maintain and repair the tissue in which they are found.” (The National Institute

of Health, 2009)

Some other differences between embryonic and adult stem cells are as follows: Embryonic

cells can become any number of different cells whereas adult stem cells are generally “limited to

differentiating into different cell types of their tissue of origin.” (The National Institute of Health, 2009)

Another major difference for consideration is the reaction after transplant. The adult stem cells come

from the patient’s own body so they are less likely to be rejected. “No therapies in humans have ever

been successfully carried out using embryonic stem cells.” (Stem Cell Research Facts, 2013)

Stem Cell Therapy involves the insertion of stem cells into the affected area in order to produce

new cells. The first successful bone marrow transplant was completed in 1968. “Bone marrow contains

somatic stem cells that can produce all of the different cell types that make up our blood”.

(Genetic Science Learning Center, 2012) Today, Stem Cell Therapy is used to treat diseases including

Cerebral palsy, Parkinson’s Disease, Leukemia, Multiple Sclerosis, and a number of cancers.

1 Stem Cells | Jennifer Lloyd

Spinal cord injuries (SCI) affect approximately 1.275 million people in the United States alone.

(Vawda, J., Wilcox, J., Fehlings, MG., 2012) These injuries are complex, there are different

levels of severity and functions that are affected by the injury. SCIs include a primary or physical injury

as well as a secondary injury which include the “molecular and cellular events which amplify the original

injury.” (Vawda, J., Wilcox, J., Fehlings, MG., 2012) Some of the effects of the secondary injury include

inflammation, ischemia, lipid peroxidation, production of free radicals, disruption of ion channels, axonal

demyelination, glial scarring, necrosis and programmed cell death. (Vawda, J., Wilcox, J., Fehlings, MG.,

(2012)

Since September 2003 there have been 16 clinical trials established to test stem cell therapy on

SCIs. Four of those trials have been completed, one suspended, one terminated, four are active and not

recruiting and six are recruiting. (U.S. National Institute of Health, 2012)

Scientists have researched a number of different Stem Cell Therapies for SCI, these include:

Olfactory Ensheathing Cells, Schwann Cells, Bone marrow stem cells, Adipose-derived Stem and

Progenitor Cells, Cord Blood/Placental Derived Cells and Fetal/ES Derived Neural Progenitors. (Ichim et

al., 2010) Based on the research I’ve done a combination of Bone marrow stem cells and the cord

blood/placental derived cells seem to show the most hope. In this scenario, the bone marrow would be

collected from the patient, as well as donated human umbilical cord tissue. Both would be tested for

quality and bacterial contamination. The patient would receive injections to the spinal fluid a number

of times over an extended period of time. The injection into the spinal fluid allows the cells to reach the

injury site in the spinal canal in order to avoid the brain barrier. (Stem Cell Institute, 2012) In clinical

trials both cord blood and bone marrow migrate to the location of the injury and differentiate into

the necessary cell. (Ichim et al., 2010) In one current SCI therapy the cord tissue-derived cell is injected

for the first three weeks followed by the bone marrow cells during the final weeks. (Stem Cell Institute,

2 Stem Cells | Jennifer Lloyd

2012)

Clinical trials are necessary for us to expand our knowledge of stem cell therapy. The ability of

stem cells to renew and repair injuries and tainted cells may be the key to a longer life span and less

pain for millions of people. After completing my research there is a new found hope that we will

continue to see the miracles of science, and stem cells will be the catalyst.

Stem Cell Paper References

The National Institute of Health. (2009). Stem cell basics. Retrieved March 18, 2013 from http://stemcells.nih.gov/info/basics/Pages/Default.aspx

Genetic Science Learning Center (2012, August 6) Stem Cells In Use. Learn.Genetics. Retrieved March 18, 2013, from http://learn.genetics.utah.edu/content/tech/stemcells/sctoday/

Stem Cell Research Facts. (2013). Why stem cells?. Retrieved March 18, from http://www.stemcellresearchfacts.org/why-stem-cells/

Vawda, R., Wilcox, J., & Fehlings, M.G (2012). Current stem cell treatments for spinal cord injury. Indian Journal of Orthopaedics, 46(1), 10-18. doi:10.4103/0019-5413.91629

U.S. National Institute of Health. (2012). ClinicalTrails.gov. Retrieved March 18, 2013 from http://www.clinicaltrials.gov/ct2/results?term=Cell+Therapy+for+SCI&cond=%22Spinal+Cord+Injuries%22

Ichim, T.E., Solano, F., Lara, F., Paris, E., Uglade, F., Rodriguez, J.P., …Riordan, N.H. (2010). Feasibility of combination allogeneic stem cell therapy for spinal cord injury: a case report. International Archives of Medicine, (1), 30.

3 Stem Cells | Jennifer Lloyd