Stem Cell Therapy

Stem cells are the mother cells that are responsible for developing an entire human body from a tiny two celled embryo; due to their unlimited divisions and strong power to differentiate into all the cells of different lineage. This power of stem cells has been harnessed by the technology to isolate them outside the human body, concentrate in the clean environment and implant back.

The general designation, “stem cell” encompasses many distinct cell types. Commonly, the modifiers, “embryonic,” and “adult” are used to distinguish stem cells by the developmental stage of the animal from which they come, but these terms are becoming insufficient as new research has discovered how to turn fully differentiated adult cells back into embryonic stem cells and, conversely, adult stem cells, more correctly termed “somatic” stem cells meaning “from the body”, are found in the fetus, placenta, umbilical cord blood and infants. Therefore, this review will sort stem cells into two categories based on their biologic properties – pluripotent stem cells and multipotent stem cells. Their sources, characteristics, differentiation and therapeutic applications are discussed.

Stem cells are divided into 2 main forms. They are embryonic stem cells and adult stem cells.

Embryonic stem cells:
The embryonic stem cells used in research today come from unused embryos. These result from an in vitro fertilization procedure. They are donated to science. These embryonic stem cells are pluripotent. This means that they can turn into more than one type of cell.

Adult stem cells:
There are 2 types of adult stem cells. One type comes from fully developed tissues such as the brain, skin, and bone marrow. There are only small numbers of stem cells in these tissues. They are more likely to generate only certain types of cells. For example, a stem cell that comes from the liver will only make more liver cells. The second type is induced pluripotent stem cells. These are adult stem cells that have been changed in a lab to be more like embryonic stem cells.

Scientists first reported that human stem cells could be changed in this way in 2006. Induced pluripotent stem cells don’t seem to be different from embryonic stem cells, but scientists have not yet found one that can develop every kind of cell and tissue.