Effect of rhHGF on colony formation. Colony formation by BM mononuclear cells (A) and purified CD34⁺ cells (B) grown with or without rhHGF in combination with GM-CSF (2 ng/mL) and erythropoietin (3 U/mL). Among 3 repeated experiments, representative data are shown. Error bars indicate standard deviation of triplicate cultures. *P < .05, culture with v without rhHGF by Student's t-test.