Sources of stem cells

Anybody who follows news reports knows that Stem Cells have been found in many parts of the human body, including discarded baby teeth. However, the concentration of Stem Cells in most body parts is a few cells per milliliter. There are only 3 sources of Stem Cells which are used for Stem Cell transplants:

1. bone marrow
2. peripheral blood (circulating in the body)
3. umbilical Cord Blood

For example, in Cord Blood the concentration of nucleated cells is millions per milliliter. It has been said that “adipose tissue”, or fat, is also a fairly rich source of Stem Cells, but not everybody is a candidate for harvesting stem cells from fat (although jokes many jokes can be made about the prevalence of obesity in the US).