STEM CELLS

     

             STEM CELLS

What  Are  STEM CELLS  ?

After a baby is delivered, the mother's body releases the placenta, the temporary organ that transferred oxygen and nutrients to the baby while in the mother's uterus. Until recently, in most cases the umbilical cord and placenta were discarded after birth without a second thought. But during the 1970s, researchers discovered that umbilical cord blood could supply the same kinds of blood-forming (hematopoietic) stem cells as a bone marrow donor. And so, umbilical cord blood began to be collected and stored.

What are blood-forming stem cells?

These are primitive (early) cells found primarily in the bone marrow that are capable of developing into the three types of mature blood cells present in our blood — red blood cells, white blood cells, and platelets. Cord-blood stem cells may also have the potential to give rise to other cell types in the body.

Some serious illnesses (such as certain childhood cancers, blood diseases, and immune system disorders) require radiation and chemotherapy treatments to kill diseased cells in the body. Unfortunately, these treatments also kill many "good" cells along with the bad, including healthy stem cells that live in the bone marrow.

Depending on the type of disease and treatment needed, some kids need a bone marrow transplant (from a donor whose marrow cells closely match their own). Blood-forming stem cells from the donor are transplanted into the child who is ill, and those cells go on to manufacture new, healthy blood cells and enhance the child's blood-producing and immune system capability.

How important is stem cell banking in today’s world?

Stem cell banking is progressively gaining importance and acceptance. It is the most straightforward way of providing natural pluripotent stem cells either to the same individual, if it was stored for personal use or as a pooled source for allogenic purpose. With the number of lifestyle disorders increasing, stem cell banking may be an important source for needy patients.

APPLICATIONS OF STEM CELLS :

Stem cells can be used to study development

 Stem cells may help us understand how a complex organism develops from a fertilised egg. In the laboratory, scientists can follow stem cells as they divide and become increasingly specialized, making skin, bone, brain, and other cell types. Identifying the signals and mechanisms that determine whether a stem cell chooses to carry on replicating itself or differentiate into a specialized cell type, and into which cell type, will help us understand what controls normal development.

 Some of the most serious medical conditions, such as cancer and birth defects, are due to abnormal cell division and differentiation. A better understanding of the genetic and molecular controls of these processes may yield information about how such diseases arise and suggest new strategies for therapy. This is an important goal of stem cell research - this poster, by EuroStemCell scientist Fiona Watt, gives an overview of what scientists have discovered so far (December 2006).

Stem cells have the ability to replace damaged cells and treat disease

 This property is already used in the treatment of extensive burns, and to restore the blood system in patients with leukaemia and other blood disorders.

 Stem cells may also hold the key to replacing cells lost in many other devastating diseases for which there are currently no sustainable cures. Today, donated tissues and organs are often used to replace damaged tissue, but the need for transplantable tissues and organs far outweighs the available supply. Stem cells, if they can be directed to differentiate into specific cell types, offer the possibility of a renewable source of replacement cells and tissues to treat diseases including Parkinson's, stroke, heart disease and diabetes. This prospect is an exciting one, but significant technical hurdles remain that will only be overcome through years of intensive research.

Stem cells could be used to study disease

 In many cases it is difficult to obtain the cells that are damaged in a disease, and to study them in detail. Stem cells, either carrying the disease gene or engineered to contain disease genes, offer a viable alternative. Scientists could use stem cells to model disease processes in the laboratory, and better understand what goes wrong.

Stem cells could provide a resource for testing new medical treatments

 New medications could be tested for safety on specialized cells generated in large numbers from stem cell lines – reducing the need for animal testing. Other kinds of cell lines are already used in this way. Cancer cell lines, for example, are used to screen potential anti-tumour drugs.