Stem cells are special cells that has the capability to
change into specialized or specific type of cells and can divide to produce
more stem cells. Stem cells are found all over the body and transform to
different types of cells at different times in our lives. These cells are
critical in helping in tissue repair and cell rejuvenation.
Types of Stem cells
Stem cells are basically classified as adult stem cells and
embryonic stem cells.
Embryonic stem cells are extracted from the blastocyst stage
during the early development of the embryo, after which the cells are placed in
laboratory dish filled with special medium for the cells to continue to grow.
These special cells are generated mainly from blastocysts that are the result
of in vitro fertilization.
Adult Stem Cells or tissue-specific stem cells since each
type of adult stem cell produces only a
limited set of specialized cells characteristic of a specific tissue ex. blood,
dermis, etc. In adults, tissue specific stem cells are found throughout the
body. Hemapoietic stem cells found in umbilical cord blood and bone morrow,
which makes up all the different blood cell types are the easiest to isolate,
and had been used for stem cell therapy for decades.
Some organs or tissues within the body contain small amounts
of tissue-specific stem cells that lie dormant, in which are reactivated when
need to repair or replace damaged or old cells. There are also active stem
cells found in the skin, blood, lining of the gut and hair cells, these organs
continuously need to produce cells in order to function properly.
Use of stem cells
Stem cells has vast applications in the field of medicine.
Many disease that are once known to be incurable can be treated with stem cell
therapy. Currently only adult stem cells are used for therapy versus embryonic
stem cells which is a more promising treatment modality, are quite
controversial because of moral issues.
