造血細胞移植術と中四国臍帯血バンクの現況

The hematopoietic stem cell transplantation (HSCT) is rapidly and widely spreading in the treatment strategy of various types of cancers, since peripheral and umbilical cord blood (CB) have been introduced as new sources of transplantable cells in addition to ordinary bone marrow cells. In this report, the current status of HSCT was reviewed. CB is rich in hematopoietic stem/progenitor cells, which have high proliferative potential. T cells in CB are speculated to be immature and immune-tolerable cells with less potential to cause acute or chronic graft versus host disease (GVHD), which are directly related with transplant-related morbidity and mortality. Furthermore, transplants with CB are not strictly restricted by a HLA-disparity. On the other hand, the less number of collected cells from CB is a major problem when the cells are applied for clinical transplantation, because the lower number of infused cells often result in engraftment failure. Further, we have no data of the viability after long term cryopreservation. We must carefully judge the usefulness of CB as a cell source for transplantation, but the benefits of CB may have a possibility to overcome these disadvantage in the near future. Finally, the activity of cord blood bank in Chugoku-Shikoku area, which was started from August 1998, was also introduced.