CSF2 and erythroleukemia: HEL cells, a human erythroleukemia cell line harboring the JAK2V617F mutation, were used as a cellular model, and cultured in the presence or absence of GM-CSF, G-CSF, EPO, SCF, and IL-3.The clone forming experiments showed that bothCHST15-WT and CHST15-Mut cells displayed cytokine-dependent growth,In the absence of growth factors, CHST15-Mutcells had stronger proliferative activity (p < 0.001), suggesting the growth manner was cytokine-independent (Fig. 5A).