SCID-repopulating cell activity of human cord blood–derived CD34−cells assured by intra–bone marrow injection

• Published in: Blood Vol. 101; no. 8; pp. 2924 - 2931
• Main Authors: Wang, Jianfeng, Kimura, Takafumi, Asada, Rumiko, Harada, Sachio, Yokota, Shouhei, Kawamoto, Yoshio, Fujimura, Yoshihiro, Tsuji, Takashi, Ikehara, Susumu, Sonoda, Yoshiaki
• Format: Journal Article
• Language: English
• Published: Washington, DC Elsevier Inc 15-04-2003; The Americain Society of Hematology
• Subjects: Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Animals; Antigens, CD34 - analysis; Biological and medical sciences; Bone Marrow; Bone Marrow Transplantation; Bone marrow, stem cells transplantation. Graft versus host reaction; Cell Lineage; Cell Movement; Cell Separation; Clone Cells - transplantation; Colony-Forming Units Assay; Cord Blood Stem Cell Transplantation; Graft Survival; Hematopoietic Stem Cells - cytology; Humans; Infant, Newborn; Injections; Lymphocytes - cytology; Medical sciences; Mice; Mice, Inbred NOD; Mice, SCID; Myeloid Cells - cytology; Receptors, CXCR4 - analysis; Severe Combined Immunodeficiency - pathology; Transfusions. Complications. Transfusion reactions. Cell and gene therapy; Transplantation Chimera; Transplantation, Heterologous; Human; Cell proliferation; Cell compartment; Lymphoid cell; Stem cell; Rodentia; Hematopoietic cell; NOD/SCID mouse; Exploration; Cell differentiation; Heterograft; Myeloid cell; Cell subpopulation; Vertebrata; Blood cell; Mammalia; Mouse; Hematopoiesis; Animal; Bone marrow; Graft; Umbilical cord
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood-2002-09-2782

Precise analysis of human CD34-negative (CD34−) hematopoietic stem cells (HSCs) has been hindered by the lack of a simple and reliable assay system of these rare cells. Here, we successfully identify human cord blood–derived CD34−severe combined immunodeficiency (SCID)– repopulating cells (SRCs) with extensive lymphoid and myeloid repopulating ability using the intra–bone marrow injection (IBMI) technique. Lineage-negative (Lin−) CD34−cells did not show SRC activity by conventional tail-vein injection, possibly due to their low levels of homing receptor expression and poor SDF-1/CXCR4– mediated homing abilities, while they clearly showed a high SRC activity by IBMI. They generated CD34+progenies not only in the injected left tibia but also in other bones following migration. Moreover, they showed slower differentiating and reconstituting kinetics than CD34+cells in vivo. These in vivo–generated CD34+cells showed a distinct SRC activity after secondary transplantation, clearly indicating the long-term human cell repopulating capacity of our identified CD34−SRCs in nonobese diabetic (NOD)/SCID mice. The unveiling of this novel class of primitive human CD34−SRCs by IBMI will provide a new concept of the hierarchy in the human HSC compartment and has important implications for clinical HSC transplantation as well as for basic research of HSC.