Stem Cells Glossary

Blastocyst - a hollow sphere of cells formed four days after a sperm fertilizes an egg.

Bone marrow - A soft, spongy tissue that fills the cavities inside most bones in the human body. Bone marrow is a source of stem cells that manufacture red blood cells, white blood cells and platelets. It is a conventional source fro stem cell transplantation.

Cellular therapy - A field of medicine that uses cells to repair tissues that have been damaged by human disease or to generate new tissues with desired functional activities.

Cord blood - Blood remaining in the umbilical cord immediately following the birth of the baby. It contains a rich concentration of stem cells.

Endogenous stem cells - Stem cells that are already present in the body.

Inner cell mass - A cluster of cells in the blastocyst from which embryonic stem cell lines can be isolated and grown in culture.

In vitro - describes a state or condition that occurs and /or exists outside the body. This term often refers to testing conditions that occur in a laboratory environment.

In vivo - describes a state or condition that occurs and/or exists within the body. This term is often used to describe testing conditions that occur within humans and/or animals.

Neuronal/neural stem cells - cells capable of becoming tissues of the brain and central nervous system.

Pluripotent - capable of giving rise to most tissues of an organism.

Stem cells - cells that have the ability to divide for indefinite periods in culture and give rise to specialized cells.

Totipotent - having unlimited capability. Totipotent cells have the capacity to specialize into extraembryonic membranes and tissues, the embryo, and all postembryonic tissues and organs.

Transplantation - the process of giving tissues or cells to treat a disease. The tissue or cells may come from the same patient (autologous) or from another person (allogenic) .