Fig. 4.
Characterization of the Lin− UCB SP for HSC properties.
(A,B) The expression of CD34 and CD38 on Lin− (A) and on Lin− SP UCB cells (B). The SP represented the dimmest 0.5% to 1.0% of the Hoechst-stained Lin− UCB cells. Quadrant statistics are provided for the individual experiment depicted. (C-F) The expression of Thy-1 (CDw90; C), HLA-DR (D), CD45RA (E), or CD71 (F) versus that of CD34 within the Lin− SP. In all panels, CD34 is depicted on the x-axis regardless of the fluorochrome used. Quadrant statistics are provided for the individual experiments depicted. Each panel is representative of at least 3 experiments. (G,H) Myelo-erythroid hematopoietic progenitors were quantified from unfractionated UCB, Lin− UCB, the Lin− SP, the CD34+Lin− SP, and the CD34−Lin− SP fractions. These were enumerated in HPCAs (G) and in 5-week LTC assays on MS5 cells (H). These data are the mean ± SD of 5 experiments. All but 2 of the HPCAs detected from CD34−Lin− SP cells were derived from cells isolated from a single sort.