Wellspring of Blood
Like bone marrow transplants, cord blood transplants can be used to treat such diseases as leukemia and aplastic anemia. Japan's first cord blood transplant took place in 1994. The remedy gained broad public attention in the country when a worker who had been exposed to radiation in the September 1999 accident at a nuclear fuel processing plant in Tokaimura, Ibaraki Prefecture, underwent cord blood transplantation to restore his blood-forming functions.

Blood taken from an umbilical cord and placenta following a birth is richer in stem cells than adult bone marrow. Stem cells are the core ingredient of all other blood cells--red blood cells, white blood cells, and platelets. By receiving transplants of these stem cells, patients with blood disorders can revive their body's ability to create healthy blood cells.

The umbilical cord and placenta had hitherto been discarded after delivery, but increasing use of cord blood means that this valuable resource will no longer go to waste. Furthermore, unlike when bone marrow is extracted, collecting cord blood imposes no burden on the donors--in this case, the mother and child. There is another significant merit to cord blood over bone marrow. Stem cells extracted from adult bone marrow cannot be successfully transplanted unless the donor and recipient have perfectly matching human lymphocyte antigen (HLA) phenotypes. But with cord blood, minor differences in the HLA phenotypes can be tolerated, and recipients' bodies are less likely to reject the transplanted stem cells.

There are still many problems to be overcome, however, as cord blood has come to be utilized for medical purposes only recently. The greatest hitch is that the amount of cord blood that can be extracted from one set of umbilical cord and placenta is between 50 cc and 100 cc, an amount that can be usefully transplanted only to small children. Another difficulty is ensuring the appropriate setting for the extraction of cord blood: Special care for the donor mother and child is needed both during delivery and immediately after, and a doctor skilled in extracting cord blood in sterile conditions must always be available in addition to the doctor overseeing delivery. After extraction, the cord blood unit needs to be immediately delivered to a cord blood bank.

Getting on the Move
In Europe the Eurocord-Cord Blood Transplant Group, established in 1994, forms a network across the region in which cord blood banks based in various countries share information and provide cord blood units for transplantation. In comparison, Japan has certainly had a late start. But research is gradually progressing in Japan, and in coming years adult patients are expected to become able to receive cord blood transplants as well.

The Japanese Cord Blood Bank Network, moreover, has recently launched a Website on which it will soon be providing information on the HLA phenotypes of cord blood units stored by the nine cord blood banks that form the network. Visitors to the site will be able to search whether any cord blood units with HLA phenotypes matching theirs are available. If a search is successful, that individual can undergo transplantation at one of 50 clinical divisions in 43 hospitals across Japan designated by the network.

Somewhat tardy though it may have been, the full-fledged launch of cord blood banking in Japan is great news for those suffering from blood disorders.

Copyright (c) 2000 Japan Information Network. Edited by Japan Echo Inc. based on domestic Japanese news sources. Articles presented here are offered for reference purposes and do not necessarily represent the policy or views of the Japanese Government.