Figure 4. Reduced severity and neutrophil recruitment in peritonitis in females.

(A-C & F) Male and female mice were treated with Group B Streptococcus (GBS; 30x10⁶ bacteria per mouse, ip; n=7 mice) for 3h. (A) Total cell number recovered from the peritoneal cavity, (B) sepsis severity score, and (C) whole blood bacterial count. (D) Phorbol ester PMA (1pg/ml)-induced NADPHoxidase activity in male and female resident peritoneal macrophage (10⁵ cells/sample), measured in vitro by Amplex® Red over 7 mins (n=3 mice). (E) GBS levels following incubation in vitro (10⁴ bacteria/sample) for 1h at 37°C with normal mouse plasma (n=3 samples from 6 mice in each group). (F) Concentration of GBS-induced cytokines in cell-free peritoneal lavage (n=7 mice). (G&H) Male and female mice were injected with zymosan A (1mg, ip). (G) Total peritoneal cell number (n=5-10; 2 independent experiments) and (H) number of F4/80+ macrophage, CD3+ T-lymphocytes, CD19+ B-lymphocytes and GR1+ granulocytes in peritoneal cavity of male and female mice 3h after injection of zymosan A (n=6 mice). All values (A-H) are expressed as mean ± sem. All comparisons are relative to male. *P<0.05, **P<0.01 and ***P<0.001 by Student’s t-test. § P<0.05 by two-way ANOVA followed by Bonferroni post-test; #P<0.001.