Figure 6. Murine neutrophil respiratory burst antimicrobial responses are most greatly affected by the presence of apoptotic bodies.

(A) C57BL/6 mice were injected intraperitoneally with saline, apoptotic bodies (5×10⁶) or zymosan (2.5 mg). Apoptotic bodies were also pre-injected 0, 2, or 4 h before zymosan injections. Cells from injected mice were harvested by peritoneal lavage and respiratory burst was assayed with DHR in peritoneal cell subpopulations based on forward scatter and side scatter profiles (Figure S4B). n = 4; * p<0.05 and ** p<0.01 compared to control; + p<0.05 and ++ p<0.01 compared to zymosan. No- no internalized particle; A.B.- apoptotic body; Zy- zymosan. (B) Histograms show representative DHR responses for total leukocytes, neutrophils and monocytes/macrophages. We found that the high responders were predominantly neutrophils (>90%). Pre-incubation with apoptotic bodies resulted in a preferential switch in the neutrophil population from high responders to mid/low responders.