Fe-SIH rescues erythroid differentiation in cdyte216/te216 mutant WKM cultured on ZKS cells. (A) Morphologic (May-Grünwald/Giemsa, top row) and histochemical (o-dianisidine, bottom row) staining of cdyte216/216 mutant WKM cultured on ZKS for 5 days with no factors added (left column) or 100 μg zEpo and Fe-SIH added (right column). Arrowheads denote erythroid cells. (B) Fold expansion of precursor cells from erythroid mutants over 5 days in culture on ZKS cell without (−) or with (+) recombinant Epo and Fe-SIH (n = 4). (C) Percent o-dianisidine-positive erythroid cells after 5 days of culture without (−) or with (+) recombinant Epo and Fe-SIH (n = 4; *P < .01). In all cases, the graph depicts the mean and SD for 4 independent replicates.