Figure 10.

Lewis lung carcinoma cells were serum-starved for 5 h and then stimulated for 20 min with darbepoetin alfa (250 ng ml⁻¹), or left untreated as a control. K562 cells, in which STAT5 is constitutively phosphorylated, were used as a positive control. After treatment, the cells were washed and lysed. Following separation of proteins by SDS–PAGE, blots were probed with anti-phospho-specific STAT5 antibody and pSTAT5 expression was analysed by X-ray autoradiography. Data represent typical results of one of three independent experiments. The membrane was stripped and probed with an antibody that recognises total STAT5 (bottom).