Significance of pH on differentiation of human erythroid cell lines.

As physiological factors and compounds, BSA and/or higher pH of the culture medium could induce the erythroid differentiation of cells. Optimum pH values of the culture medium for higher spontaneous differentiation of KU-812 and K562 cells after 7 days cultivation were 7.5 and 7.6, respectively. The synergistic effects on the differentiation were observed by exposure to hemin under the higher pH condition. In the presence of BSA, 25% of KU-812 and 40% of K562 cells became benzidine positive. Synergistic effects of BSA and the higher pH of the medium were also observed.