In recent years, cord blood transplants, peripheral blood stem cell transplants and bone marrow transplants have become mainstream treatments for patients with certain life-threatening blood, genetic or immune system disorders.

They offer hope of remission or cure for people with diseases such as leukemia, lymphoma, multiple myeloma, severe aplastic anemia, severe combined immunodeficiency, Wiskott-Aldrich syndrome, thalassemia major and sickle cell disease.

All these diseases have one thing in common. Either the disease or the treatment causes problems with the blood cells.

There are three types of blood cells:

  • White blood cells (WBC), which fight infection. If the body is lacking in WBC then immunity is weakened and become vulnerable to infections.
  • Red blood cells (RBC), which transport oxygen from the lungs to the rest of the body. With low WBC count anemia results as the body is unable to supply adequate oxygen to the cells.
  • Platelets, which help blood clot and stop bleeding after an injury. Low platelet count causes a person to bleed excessively from minor cut and injuries.

With leukemia, lymphoma and some other cancers, treatment with chemotherapy and/or radiation therapy wipes out cancerous cells, but also kills stem cells in the bone marrow. Bone marrow is where new blood cells are formed by stem cells.

People who need new, healthy blood-forming stem cells can get transplants from three sources: Bone marrow, peripheral blood stem cells or cord blood.

Sometimes, an autologous bone marrow donation is possible, where a patient’s bone marrow is collected before he or she undergoes chemotherapy or radiation therapy. Then, after the treatment wipes out the remaining bone marrow, the stem cells from the previously collected marrow are given back to the patient through an intravenous line.

However, autologous transplants are not always possible. Often, transplants must come from a donor. Around 70 percent of patients do not have a matching donor (with matching tissue type determined primarily by HLA) in the family. Their only hope is that a suitable match can be found in the National Marrow Donor Program (NMDP) registry.

Another option is cord blood; there are more than 40,000 units of cord blood in the NMDP registry.

An overview of peripheral blood stem cell transplants and cord blood transplants:
Peripheral blood stem cell transplants require the donor to donate blood (much like giving blood for blood transfusions). For a few days before donation, the donor takes medication to increase the number of stem cells circulating in the blood. Stem cells in the blood are removed and frozen for future transplantation; the rest of the blood cells are immediately returned to the donor.

Cord blood transplants use the stem cells found in the umbilical cord of newborn babies. After a baby is born and the umbilical cord is cut, blood from the cord can be processed and frozen for future use. This is only done with permission from the mother, and poses absolutely no risks for the baby. Since there is only a small amount of cord blood, cord blood transplants are usually given to children or small adults.

Recipients are given one of these types of transplants intravenously. It can take one or two years for the immune system to fully recover and function normally.

Source: East Oregonian [www.eastoregonian.info/Main.asp?SectionID=34&SubSectionID=196&ArticleID=42877]