Growth and differentiation of cord blood (CB) CD34+ hematopoietic progenitor cells (HPCs). CB CD34+HPCs unilineage cultures allow the analysis of 90-95% pure unilineage precursors as assessed by flow-cytometry and morphology. (left) Percentage of GPA, CD41, CD15 and CD14 positive cells in unilineage erythroid, megakaryocytic, granulocytic and monocytic differentiation and maturation. (right) Schematic representation of May-Grünwald-Giemsa staining of unilineage erythroid, megakaryocytic, granulocytic and monocytic cultures at various differentiation stages. Percentage of blasts, differentiating and mature cells with respect to total cells is indicated. Representative experiments are presented.