Optimal ex vivo expansion of neutrophils from PBSC CD34+ cells by a combination of SCF, Flt3-L and G-CSF and its inhibition by further addition of TPO

Table 1 Colony formation by day 0 mononuclear cells and by day 14 expanded CD34⁺ cells.

	% BFU-E	% CFU-GM + % CFU-G	BFU-E per thousand cells	CFU-GM per thousand cells	% CD34 in CFC assay	CD34 fold expansion in culture
Day 0
exp 28	74	26	35.9	12.4	2.6
exp 29	74	26	8.6	3.0	1.2
exp 32	72	28	5.0	1.9	0.4
Day 14
exp 28 SF	10	90	3.0	28.5	100	17.5
exp 28 SFG	5	95	0.8	16.1	100	33.4
exp 29 SF	18	82	1.1	4.9	100	1.8
exp 29 SFG	9	91	0.4	4.5	100	2.8
exp 32 SF	13	87	0.67	4.7	100	10.8
exp 32 SFG	0	100	0	4.7	100	32.4

CFC comparisons in 3 sets of mobilised PBSC before culture (day 0: mononuclear cell isolates, not CD34+ enriched) and after culture (day 14: expanded CD34+ enriched cells) with SCF/Flt3-L (SF) and with SCF/Flt3-L + G-CSF (SFG). The proportional (percent) results were used for qualitative comparisons. Some indication of quantitative responses can be obtained from CFC numbers, which may relate to CD34+ numbers allowing for CD34+ expansion.