The remarkable capability of developing into various types of cell in the body both during the growth and early life is only present in stem cells. In multicellular organisms, stem cells are mostly found. In addition, stem cells serve as a type of internal repair system in different tissues, categorizing essentially without limitations of replacing other cells as long as the animal or the person still lives. When the division of a stem cell takes place, each new cell born has the capability of either becoming another kind of cell along with a more specific function, like a brain cell, a red blood cell, or a muscle cell or to remain as a stem cell.

Stem cells are unique due to some of its properties. In the body, the stem cells are different from other types of cells. Regardless of their source, three specific and unique properties are present in almost all stem cells. That is they can give birth to different special types of cells, they are unspecialized, and they have the potential of renewing and dividing themselves for longer time periods. Unlike nerve cells, blood cells, or muscle cells that cannot replicate themselves normally, stem cells has the capability of proliferating or replicating different times. Moreover, millions of cells can be produced in the laboratory by an initial population of stem cells that multiplies for various months. If the outcome cells continue to be unspecialized similar to the parent stem cells, then the cells are tagged to have the potential of long-term self-renewal.

Stem cells are the continuous resources of the different cells that make up the organs and tissues of plants and animals. Moreover, they have the capability in the development of therapies for replacement of damaged or defective cells as a consequence of different types of injuries and disorders, like diabetes, heart disease, and Parkinson disease. Two of the main different kinds of stem cells are adult stem cells and embryonic stem cells. The embryonic stem cells further classify as human embryonic stem cells and mouse embryonic stem cells. Whereas, the adult stem cells further classify as neural stem cells, hematopoietic stem cells and bone marrow cells, and epithelial stem cells.

One of the biggest advantages of embryonic stem cell is that they can be decontaminated without many issues and can be easily isolated and identified. In contrast to adult stem cells, the embryonic stem cells can grow easily. Whereas, the adult stem cells are not a healthy alternative in comparison to embryo stem cells since they fall short when it comes to treatment of genetic disease. Whereas, in the adult cells the similar genetic disease that is required to be treated might take place. However, one of the major drawbacks of embryonic stem cell is that if it is used for saving the life of an individual, it may also be able to destroy life instead of saving it. For example, a significant comparison can be found between killing a comatose person and destroying an embryo.

Similarly, some of the advantages of adult stem cells are they can cure medical conditions, they have a lesser possibility of rejection, and can be used for transplants. For example, adult hematopoietic cells are also known as blood-forming cells and are typically the stem cells that are used for transplants purposes from the bone marrow. In contrast to this, some of the disadvantages of adult stem cells are invasive and expensive, can be only used for that treatment which they are harvested for, and limited availability.

Besides for spinal-cord injuries, one of the most promising and rapidly evolving treatment is provided by stem cell therapy. As different kinds of stem cells differentiate in their capability of helping to restore specific functions. Life-changing acute spinal cord injuries are suffered by Americans annually by around 230,000 individuals. Neurological compromise is eventually led by these injuries through means of death of cell within the spinal cord and through an inflammatory response. The spinal cord can be repaired through transplantation of progenitors or stem cells.