DENNIS KUNKEL MICROSCOPY / SCIENCE PHOTO LIBRARY DENNIS KUNKEL MICROSCOPY / SCIENCE PHOTO LIBRARY
Stem cell (CD34+) isolated from umbilical cord blood, scanning electron micrograph (SEM). CD34+ stem cells are normally found in the umbilical cord and bone marrow as hematopoietic stem cells. They are multipotent because they differentiate to produce precursor (progenitor) cells of any of the body's blood cell types. This process of stem cell differentiation in the circulatory system is called hemopoiesis. Hematopoietic stem cells develop either into red blood cells, or one of several types of white blood cells that make up the immune system. Blood cells have short life spans and are therefore constantly produced by the bone marrow. CD34 is a cluster differentiation molecule present on undifferentiated stem cells within the human body. It is a cell surface glycoprotein and functions as a cell-cell adhesion factor. Magnification: x3,000 when shortest axis printed at 25 millimetres.
Model release not required. Property release not required.