Effect of absence of PI3KC2β on neutrophil ROS responses to S aureus and E coli. (A) Bone marrow–derived neutrophils from PI3KC2β^+/+, PI3KC2β^+/−, and PI3KC2β^−/− animals were sonicated into SDS sample buffer, subjected to SDS-PAGE, and immunoblotted for PI3KC2β as described in “Western blotting.” PI3KC2β is indicated by →. (B) Primed bone marrow neutrophils derived from C57BL/6J WT (♦) and PI3KC2β^−/− () mice were prepared as described in “Preparation of cells” and ROS production in response to serum-opsonized S aureus (i) and E coli (ii) measured, in the presence of luminol, as described for Figure 1. Open symbols (♦, WT; , PI3KC2β^−/−) represent neutrophil ROS generation in the absence of bacterial addition. Shown are mean plus or minus range from duplicate measurements of one representative experiment of 3. Insets show mean plus or minus SEM accumulated light emission over a 40-minute measurement period for combined data, expressed as a percentage of the wild-type neutrophil responses.