The first cord blood transplant took place in 1988 when a six-year-old boy with a rare, inherited blood disorder called Fanconi’s Anaemia received his sister's cord blood stem cells. Alive and well today the success of this transplant opened the door to many more transplants around the world.

While transplant medicine is now well established and cord blood is routinely used in place of bone marrow to treat diseases such as leukaemia, other cancers and blood disorders, cord blood is also being used overseas in an emerging field called regenerative medicine.

Transplant medicine

Stem cell transplants are used to treat people whose stem cells have been damaged either by disease or by the treatment of a disease.

There are two main types of transplants – autologous and allogeneic.

An autologous transplant uses the patient's own stem cells, collected in advance and returned to them after they receive high doses of chemotherapy.

In an allogeneic transplant the stem cells are donated from another person, a genetically matched stem cell donor.

More than 1100 stem cell transplants are carried out in Australia each year. The majority of these (over two thirds) are autologous transplants [1].

Cord blood stem cells are similar to bone marrow stem cells and they have been used for the past 20 years to treat children and adults for a range of life threatening diseases including leukaemias, lymphomas, myeloma, other serious blood disorders, and some solid tumours.

• Leukemia and Lymphoma
  Historically, among the first clinical uses of blood stem cells were the treatment of cancers of the blood—leukaemia and lymphoma, which result from the uncontrolled proliferation of white blood cells. In these applications, the patient's own cancerous hematopoietic cells were destroyed via radiation or chemotherapy, then replaced with a stem cell transplant. Cancers of the blood include acute lymphoblastic leukaemia, acute myeloblastic leukaemia, chronic myelogenous leukaemia (CML), Hodgkin's disease, multiple myeloma, and non-Hodgkin's lymphoma.

• Inherited blood disorders
  Allogeneic stem cell transplants have also been used in the treatment of hereditary blood disorders, such as different types of inherited anemia (failure to produce blood cells), and inborn errors of metabolism (genetic disorders characterized by defects in key enzymes need to produce essential body components or degrade chemical byproducts). The blood disorders include aplastic anemia, beta-thalassemia, Blackfan-Diamond syndrome, globoid cell leukodystrophy, sickle-cell anemia, severe combined immunodeficiency, X-linked lymphoproliferative syndrome, and Wiskott-Aldrich syndrome. Inborn errors of metabolism that are treated with stem cell transplants include: Hunter's syndrome, Hurler's syndrome, Lesch Nyhan syndrome, and osteopetrosis. This is however, usually a treatment of last resort for otherwise fatal diseases.

• Cancer chemotherapy
  Chemotherapy targets rapidly dividing cancer cells, but unfortunately also affects rapidly dividing hematopoietic cells. In such cases, doctors may give cancer patients an autologous stem cell transplant to replace the cells destroyed by chemotherapy. They do this by mobilizing blood stem cells and collecting them from peripheral blood. The cells are stored while the patient undergoes intensive chemotherapy or radiotherapy to destroy the cancer cells. Once the drugs have washed out of a patient's body, the patient receives a transfusion of his or her stored stem cells. Because patients get their own cells back, there is no chance of immune mismatch or graft-versus-host disease.
  
  
• Treatment of tumours
  One of the most exciting new uses of stem cell transplantation puts the cells to work attacking otherwise untreatable tumours. A group of researchers have described this approach to treating metastatic kidney cancer [2].  Just less than half of the 38 patients treated so far have had their tumors reduced. The research protocol is now expanding to treatment of other solid tumors that resist standard therapy, including cancer of the lung, prostate, ovary, colon, esophagus, liver and pancreas.

Regenerative Medicine

"This revolutionary technology [regenerative medicine] has the potential to develop therapies for previously untreatable diseases and conditions. Examples of diseases regenerative medicine can cure include diabetes, heart disease, renal failure, osteoporosis, and spinal cord injuries." - US Department of Health and Human Services

While transplant medicine is probably what cord blood is best known for, cord blood is also being used overseas in an emerging field called regenerative medicine, where scientists are looking at how cord blood could be used to repair or replace damaged or diseased tissues.

Regenerative medicine focuses on regaining the remarkable regenerative capacity of tissue that all people have before birth and importantly, using your own cord blood stem cells means there is no risk of rejection by the body’s immune system.

New treatments with cord blood are now focusing on how cord blood stem cells could be used to repair damaged tissues and organs in the body. Among the primary applications are autoimmune diseases, such as juvenile diabetes and rheumatoid arthritis where the body’s immune system turns to destroying body tissues.

Other experimental approaches are looking at the potential of cord blood stem cells to treat conditions like cerebral palsy and brain injury.
Tissue engineering and treatments for hearing loss are other areas in development.

The following chart summarises autologous cord blood treatments that have taken place around the world in the field of regenerative medicine. By the end of 2009 there were at least 211 autologous treatments, using cord blood from at least 18 different family banks around the world. This data was researched and compiled by Frances Verter (parentsguidecordblood.com).

Table 1: Autologous cord blood treatments

[1] Australian Bone Marrow Transplant Recipient Registry Annual Data Summary 2006
[2] Childs, R., Chernoff, A., Contentin, N., Bahceci, E., Schrump, D., Leitman, S., Read, E.J., Tisdale, J., Dunbar, C., Linehan, W.M., Young, N.S., and Barrett, A.J. (2000). Regression of metastatic renal-cell carcinoma after nonmyeloablative allogeneic peripheral-blood stem-cell transplantation. N. Engl. J. Med. 343, 750–758