Absence of a CD34- hematopoietic precursor population in recipients of CD34+ stem cell transplantation

Bone Marrow Transplant. 2001 Sep;28(6):587-95. doi: 10.1038/sj.bmt.1703186.

Abstract

The purified CD34(+) cell fraction has been used for hematopoietic stem cell transplantation since they were demonstrated to have long-term reconstituting ability. Therefore, the potential effects of CD34(-) stem cells on the clinical course have been a major concern in recipients of CD34(+)-selected transplantation. To address this concern, we used an in vitro assay to determine whether transplant recipients have CD34(-)precursor population. Lin(-)CD34(-) cells were isolated from bone marrow cells in 11 transplant recipients including four CD34-selected transplantations, six standard bone marrow transplantations, and one T cell-depleted marrow transplantation. The frequency of the Lin(-)CD34(-) population in four CD34-enriched transplantation recipients was not different from those of normal donors or recipients of other modes of transplantation: 0.96 +/- 1.01% (mean +/- s.d., n = 4), 0.45 +/- 0.16% (n = 6), and 0.66 +/- 0.59% (n = 7), respectively. However, the Lin(-)CD34(-)population obtained from the recipients of CD34-enriched transplantation acquired neither CD34 expression nor colony-forming activity after 7 days of culture, whereas the cells from all the normal individuals and standard BMT recipients were able to differentiate into CD34(+) cells accompanied by the emergence of colony-forming activity.We conclude that recipients of CD34-enriched transplantation appear to have defects in their CD34(-) precursor population. The clinical significance of these defects will be determined in a life-long follow-up of these patients.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Antigens, CD34 / analysis*
  • Bone Marrow Cells / cytology
  • Bone Marrow Cells / immunology*
  • Cell Culture Techniques
  • Cell Division
  • Child
  • Child, Preschool
  • Colony-Forming Units Assay
  • Hematopoietic Stem Cell Transplantation / methods*
  • Hematopoietic Stem Cells / cytology
  • Hematopoietic Stem Cells / immunology*
  • Humans
  • Immunophenotyping
  • Infant
  • Lymphocyte Depletion
  • Tissue Donors

Substances

  • Antigens, CD34