The role of the state in establishing a public cord blood stem cell bank.

Allogeneic stem cell transplantation has become a curative treatment option for many patients with haematological malignancies, bone marrow failure syndromes, thalassaemia, sickle-cell disease and some rare disorders of the blood and bone marrow. Ideally, stem cells from the peripheral blood or bone marrow are sourced from sibling donors or from a matched unrelated donor if a sibling donor is not available. Alternatively, stem cells may be obtained from umbilical cord blood (UCB). The advantages of the latter over conventional sources of stem cells include that tissue matching requirements are less stringent, healthy donors are not exposed to invasive procedures, and transplants can be performed without delay. Cord blood as a source of stem cells is rapidly changing the face of regenerative transplantation. 1 The voluntary donation of cord blood cells to public UCB banks, resembling blood donation practice, is an example of a social justice health model that encompasses ethical citizenship and altruism. 2 Van Rood's proposal on international transplant-sharing associations 3 has been made a reality by public UCB banks. Such 'allogeneic tissue networks', formed by linking international registries, are scientifically and ethically easier to justify than private UCB banks that store autologous stem cells for exclusive use by the donor or a close relative. The likelihood that a child will require and receive its own cord blood as a transplant within 10 years of storage is very low, 4 and the potential need for autologous use of a stored UCB unit is estimated to be between 0.04 and 0.0005%. 5 The potential estimated need is not the same as the likelihood of actually receiving an UCB transplant; the latter is much lower. 4 On the other hand, the probability of requiring an allogeneic stem cell transplantation is estimated to be 0.04% by age 20 years, 0.10% by age 40, and 0.25% by age 70. These are orders of magnitude higher than the probabilities of requiring an autologous stem cell transplant. 2 Nevertheless, several limitations to the use of UCB stem cells in adult patients must still be overcome; low stem cell dose is a significant challenge. 6 Public UCB banks and systems such as the international bone marrow registries, which rely on voluntary peripheral blood stem cell donations, are positioned well to systematically address issues such as inequitable access to stem cell transplantation caused by stem cell shortages and the possible lack of genetic diversity of the stem …