Patients with leukemia, lymphoma, thalassemis major or certain inherited metabolic or immune system disorders have diseased blood-forming cells. For some patients, a cord blood or bone marrow transplant (also called a BMT) may be their best treatment option.
Cord blood is the blood that remains in the umbilical cord and placenta following birth. Like bone marrow, it is a rich source of stem cells, the building blocks of the human immune system. Stem cells reproduce into red blood cells, which carry oxygen throughout the body; white blood cells, which fight infection; and platelets, which aid in blood clotting. Compared to bone marrow collection, cord blood collection is non-invasive, painless, less expensive and relatively simple. Some major advantages of cord blood transplantation are less frequent occurrence of graft vs. host disease (GVHD), greater tolerance for a partial HLA (tissue type) match and less risk and discomfort to the donor.
The first cord blood transplant was performed in 1988. Since then, more than 2000 transplant-ations have been performed using cord blood worldwide. The overall success in these transplant-ations has been remarkable, with an approximately 90 percent engraftment rate and a 40 percent probability of disease-free survival
Cord Blood Transplantation (2)
The Sibling Donor Cord Blood Program at Children's Hospital Oakland was developed to serve families of patients with thalassemia and sickle cell disease. The Center offers a variety of services, including:
- outreach and recruitment
- patient and family education
- infectious disease screening
- cord blood collection programs
- genetic (HLA) typing
- processing for long-term storage
Collection and Preservation
Umbilical cord blood is collected at birth. It involves taking blood from parts of the birth that are normally discarded. The doctor performing the collection has all the materials necessary in the labor room. The blood can be collected from the umbilical vein several ways:
The final container is labeled properly and taken to the lab for processing. The blood is tested for several infectious diseases, including HIV and hepatitis. And if not already done through amniocentesis or chorionic villus sampling, the blood is HLA-typed. The blood is cryopreserved at - 90 degrees Celsius, then stored in liquid nitrogen until needed. Whether an adult can be successfully and sufficiently transplanted using umbilical cord blood remains to be seen.
The final container is labeled properly and taken to the lab for processing. The blood is tested for several infectious diseases, including HIV and hepatitis. And if not already done through amniocentesis or chorionic villus sampling, the blood is HLA-typed. The blood is cryopreserved at - 90 degrees Celsius, then stored in liquid nitrogen until needed. Whether an adult can be successfully and sufficiently transplanted using umbilical cord blood remains to be seen.
- The blood can be drained from the severed end of the cord during the third stage of labor (an open system) into a sterile container with an anticoagulant.
- The blood can be collected through venipuncture (a closed system) and drained into an anticoagulated bag. A syringe is placed in a three-way stopcock and used to suction if the blood does not flow naturally. Once the blood does stop flowing, the cord can be gently "milked." This is a preferred method because of the reduced risk of contamination.
- When the placenta is delivered, another 20-40 mL or more can be collected from the lake at the root of the cord by gentle reverse milking of the cord and multiple aspirations of the engorged vessels on the fetal surface.
- Cord blood can also be collected after the separation of the placenta. The placenta is suspended from a specially-designed stand with the cord and fetal material hanging down. Gravity drains the blood into a container.
Treating Thalassemia
The vast majority of individuals who have thalassemia do not require regular blood transfusions. There is a small group of individuals who will require a blood transfusion occasionally, and an even smaller group who require transfusions on a regular basis. Generally, this category refers to individuals who are transfusion-independent or who have had a few or occasional transfusions, but who do not need regular, chronic transfusions in order to thrive. The non- or intermittently-transfused patient will usually have beta thalassemia intermedia, Hemoglobin H disease, Hemoglobin H-Constant Spring, or a milder manifestation of E-b thalassemia.
Over the past several decades with the progress of medical technology, this once universally fatal disease has been converted to a chronic illness. Now a fortunate few have the opportunity of cure. Only a precious few children who have this complex disease will be cured by a bone marrow transplant. The rest of these children need continued support and acceptance that they may live normal healthy lives in spite of their illness.
In this section, you will find comprehensive information on the therapies used to treat Thalassemia including blood tranfusion and blood and bone marrow transplantation.
