Stem Cell Usage to Cure Leukemia

Individuals diagnosed with leukemia may receive stem cell transplants as a form of treatment. Transplant materials can be used for more than one purpose, depending on the condition of the individual. The stem cells used can be taken from a donor, or taken from the patient's own bone marrow. Each method holds a certain degree of risks and benefits.

Identification

• Leukemia is a type of cancer that affects how blood-forming cells are produced within a person's bone marrow. Instead of producing white blood cells according to the body's needs, these cells reproduce at an uncontrolled rate. In order to treat this condition, the stem cell materials contained inside the bone marrow must be replaced, or else the cancerous cells themselves must be destroyed. Stem cell transplant procedures are a form treatment used to replace cancerous cells with healthy ones. Transplant procedures can also be used to replenish cells that have been destroyed by chemotherapy treatments. The stem cell materials used to cure leukemia can be obtained from the patient's own bone marrow, from an adult donor, or donor umbilical cord cells.

Function

• The stem cells contained inside bone marrow are made up of immature cells called hematopoietic, or blood-forming cells. Hemotopoietic cells are constantly dividing to form more stem cells. These cells can also mature and become one of the three blood cell types: white cells, red cells or platelets. When leukemia is present, hemotopoietic cells manufacture an unneeded number of white blood cells. A transplant procedure may involve drawing hemotopoeitic cells out of the bone marrow and into the blood stream. Once in the bloodstream, stem cell materials can be extracted for future use.

Autologous Transplants

• Autologous transplant is the term used when the patient's own cells are used. This process entails destroying the cancerous cells after stem cells have been removed, and then re-implanting them into the bone marrow. Cell materials are treated with immunologic agents or heat in order to eliminate leukemic, or cancerous cells. There is no guarantee that all of the cancerous cells will be destroyed, and because of this, autologous transplants are not the preferred treatment approach.

Peripheral Transplants

• Peripheral transplants involve drawing stem cells into the bloodstream so stem cell materials can be extracted. Cells are filtered out of the blood through a process called pheresis. The blood is then returned to the patient. Prior to pheresis, patients receive high doses of radiation therapy in order to kill off existing cancer cells. In some cases, the extracted stem cells will be used as material for autologous transplant procedures, though the procedure may be done for the sole purpose of removing cancer cells from bone marrow materials.

Allogenic Transplants

• Allogenic transplant procedures, also known as allogenic bone marrow transplants, involve the use of donor stem cell materials. Donors are typically blood relatives with compatible blood types. Blood type compatibility is determined by a protein marker found on the surface of white blood cells, or leukocytes. Donor transplants not only provide a healthy source of stem cells, but may actually help fight off any developing cancer cells within the patient's bone marrow. Allogenic transplants do carry the risk of the patient's body rejecting the donor stem cells. To prevent this from happening, patients receive drugs designed to suppress rejection reactions prior to the transplant procedure.