RT-PCR on Gr-1⁺, Fc-γ R⁻ cells from normal bone marrow cells cultured with rIL-3, rIL-5, and rGM-CSF. (A) Flow cytometric analysis of the initial population and of the postsort Gr-1⁺ Fc-γ R⁻ cells used for further RT-PCR analysis. (B) RT-PCR analysis of sorted cells using the same primers and conditions as described in Fig 2. Similar results were obtained on four different experiments.