Biology and Function of Stem Cells

Abstract

Looking for the exact definition of stem cell is sometimes the source of endless semantical debates. There are two generally accepted criteria: a high capacity for self-renewal and the potential for multipotent or pluripotent differentiation. Stem cells are unspecialized cells that renew themselves through series of cell divisions, which result in similar unspecialized stem cells. Under certain physiologic or experimental conditions, they can be induced to become differentiated cells with special functions. The resulting progenitor cells differentiate into functional, specialised cells of the organism. In this chapter we provide standard criteria and definitions for stem cells.