Functional characterization of 7/4⁺ populations. (A-B) Phenotypic changes of the 7/4⁺Gr-1^int population during inflammation. (A) Down-regulation of 7/4 and increase in scatter properties, 4 hours (R1) and 24 hours (R2) after TG. (B) Up-regulation of activated Mφ markers, 4 hours (R1, solid line), 24 hours (R2, gray fill), and isotype control at 24 hours (dotted line) after TG. (C) Phagocytosis of FITC E coli by matured bone marrow 7/4⁺Gr-1^hi (black) and 7/4⁺Gr-1^int (gray) cells (percent of 7/4⁺ gate in each quadrant is indicated). (D) Superoxide burst in response to PDBu. Geomean FL-1 values prior to and after stimulation were, respectively, 5.5 (solid line) and 56.7 (gray fill) for Gr-1^hi and 8.7 (solid line) and 28.1 (gray fill) for Gr-1^int cells.