Hematopoietic stem cell transplantation is the only treatment that can be expected to cure patients with intractable blood diseases such as leukemia and aplastic anemia.Among them, cord blood transplantation is an important transplantation method that is carried out in more than 1,000 cases a year in Japan.Cord blood transplantation is expected to become more and more important in the future, but there are clinical issues such as the inability of hematopoietic stem cells contained in the transplanted cord blood to function well in the bone marrow and the slow recovery of white blood cells and platelets. I haven't overcome it yet.

　The group discovered and identified CD2003 antigen-negative hematopoietic stem cells (hereinafter referred to as "human umbilical cord blood-derived CD34⁻HSC") by developing a direct bone marrow transplantation method in 34.Through a series of subsequent analyzes, we have now succeeded in almost completely purifying human cord blood-derived CD34⁻HSC to a level that allows transplantation experiments and gene analysis in single cells.Examination of the properties of this purified CD34⁻HSC revealed that it is an undifferentiated HSC that has both self-renewal ability and long-term bone marrow remodeling ability, and that it has a high ability to differentiate into erythrocyte / megakaryocytic cells. I made it. A series of analyzes suggest that CD34⁻HSC is the most undifferentiated hematopoietic stem cell.

　This result is expected to contribute to the healing of patients suffering from diseases, such as application to the establishment of human stem cell (HSC) banks in the future.

Paper information:[Nature Communications] A Revised Road Map for the Commitment of Human Cord Blood CD34-negative Hematopoietic Stem Cells