ISOLATION AND PHENOTYPIC CHARACTERIZATION OF CD117-POSITIVE CELLS

Mononuclear cells derived from cord blood were stained using the CD117 -specific, fluorochrome-labeled monoclonal mouse antibody 95C3. Additi onal staining was performed using an isotype-specific rat-anti-mouse a ntibody, labeled with supermagnetic microparticles. Target cells were enriched by the technique of magnetic cell separation, MACS. The resul ting cell population contained 96.5% (+/-1.7% S.D.) CD117-expressing c ells (n = 12) with different levels of CD117 antigen expression. Using flow cytometry, two cell populations differing in size were found. A majority (93%) of cells with high forward scatter revealed a phenotype positive for CD117 and CD34. Isolated cells revealed a high fraction of hematopoietic progenitors (16%). The technique presented allows for an alternative approach of stem cell enrichment and might be useful i n autologous transplantation of cells with hematopoietic properties. C opyright (C) 1996 Elsevier Science Ltd.