What is a Blood Stem Cell Transplant?

Blood stem cell transplants include bone marrow, stem cell and cord blood transplants.

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A blood stem cell transplant is a medical procedure used to treat people with a variety of life-threatening diseases.

More than 50,000 people worldwide undergo a blood stem cell transplant each year.

The technical name for a blood stem cell transplant is a hematopoietic stem cell transplant (HSCT). You may also hear the procedure referred to as a:

  • bone marrow transplant
  • stem cell transplant (or peripheral blood stem cell transplant)
  • cord blood transplant

Throughout this website, we will use the term stem cell transplant to refer to all three types of transplant.

Since the 1950s when modern-day blood stem cell transplantation began, thousands of patients have enjoyed a second chance at life, thanks to a blood stem cell transplant.

Watch a Video about the History of Bone Marrow, Stem Cell and Cord Blood Transplantation

What are blood stem cells (hematopoietic stem cells)?

Blood stem cells are special cells that enable one's body to produce:

  • white blood cells, that are need to fight infection;
  • red blood cells, that carry oxygen to, and remove waste from, our body's cells;
  • platelets, that help blood clot

Blood stem cells live in the bone marrow - the spongy tissue inside our bones. Blood stem cells are also found in the discarded placenta and umbilical cord of newborn babies.

Who Needs a Bone Marrow, Stem Cell or Cord Blood Transplant?

Sometimes the blood stem cells in bone marrow malfunction and being producing

  • too many
  • too few or
  • defective blood cells. 

A blood stem cell transplant may be needed to correct this condition.

For patients with certain cancers, the most effective treatment may be very high dosages of chemotherapy and/or total body irradiation. This therapy destroys not only the diseased cells, but blood stem cells as well. A stem cell transplant may be needed to "rescue" the patient from this life-threatening side effect.

A blood stem cell transplant may also be a treatment option for patients with certain inherited diseases such as immune deficiency diseases.

Different Types of Blood Stem Cell Transplants

There are different types of blood stem cell transplants. The type of transplant varies according to the source of blood stem cells.

  • Bone marrow transplants (BMT) use blood stem cells collected from the bone marrow.
  • Peripheral blood stem cell transplants (PBSCT) use blood stem cells collected from the bloodstream.
  • Cord blood transplants (CBT) use blood stem cells collected from the discarded placenta and umbilical cord of a new born baby. 

The type of transplant also varies according to who provides the cells for the transplant.

  • Autologous (aw-TOL-o-gus) transplants use cells previously collected from the patient.
  • Allogeneic (al-o-je-NAY-ik) transplants use cells provided by a donor.
  • Syngeneic (sin-je-NAY-ik) transplants use cells provided by an identical twin.

Prior to transplant, patients receive high dosages of chemotherapy and/or radiation to destroy their disease and make room for healthy new blood stem cells.

  • If the dosage of chemotherapy and/or radiation is high enough to completely suppress the patient's immune system, the procedure is called a myeloablative transplant
  • If a patient receives less intensive dosages of chemotherapy and/or radiation, the procedure is called a reduced intensity or nonmyeloablative transplant.

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Next Page: Diseases Treated by Transplant