Immunofluorescence analysis of bone marrow cells.

(A) Bone marrow was prepared from wild type mice (+/+), lys-EGFP⁺/ki mice, and mice in which the neo gene had been deleted (⁺/ki-neoD). The cells were stained with various primary antibodies (indicated on the left), and a PE-labeled secondary antibody was followed by flow-cytometry analysis. The profiles show GFP fluorescence (green) on the horizontal axis and antibody-mediated fluorescence (red) on the vertical axis. The percentage of cells in each of the 3 quadrants containing fluorescence-positive cells (antibody only, antibody/GFP, and GFP only) is indicated either within the respective quadrant or immediately adjacent to it. Specificity of the antibodies: CD3, T cells; Mac-1, macrophages and myelomonocytic cells; ER-MP12, immature monocytic cells; ER-MP20, monocytic (and some granulocytic) cells; Ly6-G (Gr-1), neutrophil granulocytes; Sca-1, early multilineage progenitors; Ter119, erythroid cells; and B220, cells of the B-cell lineage. (B) Micrograph of live cells from alys-EGFP-ki/ki-neoD mouse. Cells were stained with anti-B220 antibody coupled to PE and photographed under a brightfield to reveal antibody-positive cells (red surface staining) as well as under epifluorescence illumination to reveal EGFP⁺ cells (green cells). The field contains 9 B220⁺ cells, 11 EGFP⁺ cells, and 2 double-negative cells (as well as 2 cell ghosts).