Uses of Human Stem Cells

Stem cells have the ability to become any type of human cell in early periods of life. They can divide an unlimited number of times, which makes them useful for repairing systems of the body. Due to their capacity to replenish themselves, human stem cells have many medical uses.

Characteristics of Stem Cells

• Stem cells are unique from other cells due to their ability to divide and renew themselves. Cell division of these unspecialized cells allows the body to create new cells that can become cells with needed functions. Secondly, stem cells that divide into additional unspecialized cells are helpful in replacing damaged tissue in vital organs of the body.

Types of Stem Cells

• There are two types of stem cells: embryonic and somatic/adult stem cells. Embryonic stem cells are extracted from blastocysts, a few-day-old embryo. These cells are pluripotent, meaning that they can develop into any type of cell by differentiating into a germ layer of the embryo including the endoderm, mesoderm or ectoderm. Adult stem cells are somatic, which means they are found in the body, not the embryo. These stem cells can only develop into the cell types of their original tissue.

Research Uses

• Researchers can use stem cells to learn about the events leading to human development. They extract the cells to determine the processes that the stem cells go through to differentiate into specific cells. Scientists follow the pathways of development that lead to cancers or other abnormalities in cells to identify how they may develop treatments for those developmental problems. They perform tests by shutting off or turning on genes or regulating cell division.

Medical Uses

• Due to the ability to differentiate into any type of cells, scientists are using stem cells to treat diseases. The unlimited division of stem cells creates a renewable source of cells and tissue to repair cells whose defects have caused strokes, diabetes, arthritis and Alzheimer's disease. By injecting healthy stem cells into a defective body tissue, the stem cells have a positive effect, which can lead to rejuvenation and repair of that tissue.

Controversy

• There is a continuing debate over whether the use of human stem cells will lead to cloning, which degrades the value of human life. Opponents find that stem cell research will lead to unethical practices, while supporters assert that the research will only have a positive impact on medical treatments.