Table 2.

Dose effect of ZnPP and SnPP on human bone marrow erythroid CFU-E and BFU-E growth

Additions	% of control growth
	CFU-E, 142 ± 9/5 × 105 cells	BFU-E, 94 ± 6/5 × 105 cells
Epo alone	100	100
+ ZnPP, μM
1	80	79
5	64	51
10	49*	36*
20	32*	23*
+ SnPP, μM
1	101	100
5	99	102
10	103	98
20	100	104

Human bone marrow cells were grown in methylcellulose cultures in the presence of 1–2 units per ml of Epo for CFU-E and BFU-E, respectively. Additions of analogues were made and then colonies scored after 7–14 days of incubation at 37°C. Control numbers of CFU-E and BFU-E are given as (M ± SEM), n = 6, and remaining results presented as percent of control growth. 

^*P < 0.001.