The Cord Blood

What is a stem cell?

Any cell which has the inherent capabilities of unlimited cell cycles, (the cell division creates two identical daughter cells. Those two daughter cells create two more identical daughter cells each and proceed further to divide. It is in geometric proportion and in due time produces 2, 4, 8, 16, 32, 64 etc. of identical daughter cells (For Somatic cells we have already seen this happen during the process “Mitosis”), with in built capacity to stop itself from being a stem cell and transform into one of a variety of cells that are specialized (fat cells, cartilage etc.) which has no further capacity to unlimited division.

Adult stem cells are found in adult organs which are limited to commit itself to the type of tissue found in the organ where they are populated. They are seen in organs like: Liver, Stomach-lining, the skin, bone, spermatozoa, bone-marrow etc. It is seen that though they are generated. Lining of our Liver is done once in six weeks. Our skin gets itself renewed once in a month. Our Gut (stomach) lining gets renewed every five days. Our skeletal system gets replaced in every three months. Our blood vessels actually repair damages and, in fact, are capable of regeneration. Also it is seen that the tests being developed in fetus contain stem cells but lie in wait patiently for puberty to happen. Once a male reaches puberty, the testes generate billions of spermatozoa on a daily basis which continue through the rest of the lifespan of that male.

What are the essential peculiarities of Adult Stem Cells?

• They always retain their expertise to cell – cycle, i.e., to divide themselves into daughter cells.
• They have the inherent capabilities to transform into a particular cell type. Example: A skin stem cell can only be a skin stem cell and cannot transform into a gut-lining stem cell. A spermatozoon stem cell can never become a Liver stem cell.
• The crux is that Adult Stem Cells can be successfully used only to carry out repairs to the tissues or organs from which they emerge.