Adult Stem Cell Awareness

FAQs

 

What are adult stem cells?

What is the difference between adult stem cells and embryonic stem cells? What is the controversy about?

What is the difference between autologous and allogeneic stem cells?

Why should I be excited about adult stem cell transplants?

 


What are adult stem cells?

An adult stem cell is an undifferentiated cell, found among differentiated cells in a tissue or organ that can renew itself and can differentiate to yield some or all of the major specialized cell types of the tissue or organ. The primary roles of adult stem cells in a living organism are to maintain and repair the tissue in which they are found. Unlike embryonic stem cells, which are defined by their origin (cells from the preimplantation-stage embryo) the origin of adult stem cells in some mature tissues is still under investigation.

Research on adult stem cells has generated a great deal of excitement. Scientists have found adult stem cells in many more tissues than they once thought possible. This finding has led researchers and clinicians to ask whether adult stem cells could be used for transplants. In fact, adult hematopoietic, or blood-forming, stem cells from bone marrow have been used in transplants for 40 years. Scientists now have evidence that stem cells exist in the brain and the heart. If the differentiation of adult stem cells can be controlled in the laboratory, these cells may become the basis of transplantation-based therapies.

The history of research on adult stem cells began about 50 years ago. In the 1950s, researchers discovered that the bone marrow contains at least two kinds of stem cells. One population, called hematopoietic stem cells, forms all the types of blood cells in the body. A second population, called bone marrow stromal stem cells (also called mesenchymal stem cells, or skeletal stem cells by some), were discovered a few years later. These non-hematopoietic stem cells make up a small proportion of the stromal cell population in the bone marrow, and can generate bone, cartilage, fat, cells that support the formation of blood, and fibrous connective tissue.

*Source: National Institutes of Health

Adult stem cells offer the possibility of a renewable source of replacement cells and tissues to treat a myriad of diseases, conditions and disabilities. Adult stem cells are relatively quiescent (inactive) cells, particularly in organisms where cell turnover is low, yet they can mount a rapid and strong response to tissue stress and injury.


What is the difference between adult stem cells and embryonic stem cells? What is the controversy about?

There are two primary types of stem cells, embryonic and adult stem cells. As the name suggests, the controversial embryonic stem cells are derived from embryos, which has triggered much public debate over the past few decades due to the destruction of an embryo following cell extraction.

In contrast, adult stem cells are derived from adult tissues and with consent from the patient. As a result, there is little or no ethical or religious debate surrounding adult stem cell removal.


What is the difference between autologous and allogeneic stem cell transplants?

Autologous adult stem cell transplants involve using an individual’s own cells, which are removed, then enriched or processed, and then returned to the body. When a patient’s own adult stem cells (autologous cells) are used to treat the patient, there are clinical and economic advantages, as there are no issues with immune rejection.

In an allogeneic transplant (where you’re using somebody else’s cells), for example for treating cancer patients, the donor cells are intended to provide the patient with new blood cells and a new immune system. The donor cells are obtained from a Human Leukocyte Antigens (HLA) matched individual, and may be obtained from cord blood, a related donor who is a match (based on HLA, the genetic markers of the immune system) or could be from unrelated donors.


Why should I be excited about adult stem cell transplants?

Adult stem cells offer the possibility of a renewable source of replacement cells and tissues to treat a myriad of diseases, conditions and disabilities. Adult stem cells are relatively quiescent (inactive) cells, particularly in organisms where cell turnover is low, yet they can mount a rapid and strong response to tissue stress and injury.

Adult stem cell transplants (bone marrow transplants) have been used for over 40 years in successfully treating cancers such as leukemia, multiple myeloma and lymphomas, and research has now opened the doors to regenerative and reparative therapeutics. There has been an increase in adult stem cell therapy clinical trials which are showing great promise in the areas of skin and wound healing, orthopedics, and in treating diseases including peripheral vascular disease, scleroderma, diabetes, congestive heart failure, myocardial infarction, and much more.