Figure 4.
Neutrophil-derived supernatants promote B cell proliferation and survival. [3H]Thymidine incorporation by human tonsillar B cells (A) and flow cytometry analysis on FSC/SSC plots of splenocytes from C57BL/6J mice (B) were assessed after a 4- or 3-d culture, respectively, with 5 ng/ml rBLyS or conditioned medium prepared from G-CSF–stimulated neutrophils, in the absence or presence of 0.3 μg/ml of neutralizing anti-BLyS mAbs. 10−5 dilution SAC was added as a costimulus for the proliferation assay. Cell-free culture medium containing G-CSF was used as a control. Values in A are expressed as the mean number ± SEM of triplicate determinations calculated from three independent experiments. The plots in B are representative of three separate experiments.