<i>Cd55^-/-</i> and <i>Cd97^-/-</i> mice have an increased granulopoietic capacity.

<p>(<b>A</b>) Blood was collected from wild-type and <i>Cd55</i>^-/- mice two days before and 30 min after i.p. injection of 0.25 mg/kg epinephrine, and the number of granulocytes per ml blood was measured by flow cytometry. Bars and error bars represent the mean and SD of the number of granulocytes (n = 3-5). (<b>B</b>) PBL from wild-type and <i>Cd55</i>^-/- mice, cultured overnight at 37°C, were stained with Mitotracker and analyzed by flow cytometry. Shown is the mean and SD of the percentage of Mitotracker-negative apoptotic granulocytes (n = 4). (<b>C</b>) Blood was collected from wild-type and <i>Cd55</i>^-/- mice via vena saphena puncture at the indicated time points after a single i.p. injection of 5 mg BrdU. PBL were stained for Ly6G and BrdU and analyzed by flow cytometry (left panel). The mean and SD of the percentages (left panel) and absolute numbers (right panel) of BrdU-positive granulocytes are depicted (n = 3–5). (<b>D</b>) Wild-type, <i>Cd55</i>^-/-, and <i>Cd97^-/-</i> bone marrow cells were harvested and analyzed by flow cytometry for dividing cells. To the left, representative histograms showing the percentage of granulocytes with > 2N DNA content in wild-type, <i>Cd55</i>^-/-, and <i>Cd97</i>^-/- mice are provided. To the right, the mean and SD of the percentage of granulocytes with > 2N DNA content is depicted (n = 3–4). One of two comparable experiments is shown. *, p<0.05 and **, p<0.005