Phenotypic Definition of the Progenitor Cells with Erythroid Differentiation Potential Present in Human Adult Blood

Table 1

Summary of the number of cells recovered in each fraction after CD36/CD34-based purification and of their growth in HEMA culture. Results with MNC and population A are presented as mean (±SD) of those obtained in three separate experiments. Results with population E are representative of two independent experiments, while a complete data set for populations B and C is available only from one experiment.

Cell population		Cells obtained from1 buffy coat	Recovery (%)*	FI in HEMA; (Day 14)	Total theoretical number of EBs generated in HEMAat day 14**
	MNC	272 (±86)×10^6	100%	10.1±1.4	2.7×10^9
	CD34^posCD36^neg	75 (±53.5)×10^3	27.5%	9,347±950	7.0×10^8
	CD34^posCD36^pos	9,500	3.5%	113	1.1×10^6
	CD34^negCD36^low	7,500	1.4×10^−3%	62.5	5.0×10^5
	CD34^negCD36^neg	2–10×10^6	1.0–4.9%	1.14–3.5	0.2–3.5×10^7

*Recovery was calculated by dividing the total number of cells obtained after the purification per the theoretical number of cells present in MNC. The theoretical cell number of each fraction was calculated by multiplying the frequency of the population, presented in Figure 1(a), per the average number of MNC obtained from an AB buffy coat (272×10⁶).
**The theoretical total number of EBs obtainable at day 14 from each fraction was calculated by multiplying the total cell number of the fraction per the corresponding FI.