Figure 2. MAIR-II regulates the influx of iMo to the peritoneal cavity after CLP.

(a,b) Numbers of total cells, Mφ/Mo (CD11b⁺ F4/80⁺), neutrophils (CD11b⁺ F4/80⁻ Ly6G⁺) and apoptotic cells (PI⁺) in the peritoneal cavity of WT or AF251705^−/− mice, 8 (n=5) or 20 h (n=15) after CLP operation. (c) Liposome-encapsulated PBS- or liposome-encapsulated dichloromethylene bisphosphate (Cl₂MBP)-treated WT and AF251705^−/− mice were subjected to CLP. Mice were monitored every 6 h for 6 days to determine survival (n=9–11 per group). (d) Flow cytometry analysis of MAIR-II expression on iMo (Ly6G⁻ F4/80^high Ly6C^high), patrolling monocytes (pMo) (Ly6G⁻ F4/80^low Ly6C^low) and neutrophils (Ly6G^high F4/80^low) in the bone marrow. (e,f) iMo from WT or AF251705^−/− mice were intravenously transferred into AF251705^−/− mice after CLP and monitored every 6 h for 6 days to determine survival (n=10 per group). Mock indicates mice that received PBS alone after CLP (e). Bacterial titres in the peritoneal cavity 20 h after CLP were determined by colony-forming unit (CFU) assay (f). (g) CFSE-labelled iMo from WT or AF251705^−/− mice were intravenously transferred into AF251705^−/− mice 20 h after CLP. Numbers of migrated CFSE⁺ iMo in the peritoneal cavity were analysed by using flow cytometry 20 h after CLP (n=10 per group). (h) The mixture of equal number of CFSE-labelled WT (CD45.1⁺) and AF251705^−/− (CD45.2⁺) iMo were intravenously transferred into AF251705^−/− mice immediately before CLP. The proportions of transferred CD45.1⁺ (WT) and CD45.1⁻ (AF251705^−/−) iMo in the peritoneal cavity were analysed by using flow cytometry 20 h after CLP (n=4 per group). N.S., not significant. *P<0.05, **P<0.01 and ***P<0.001 (two-tailed Student’s t-test in (a,b,g,h), log-rank test in (c,e) and Mann–Whitney U-analyses in f). Error bars indicate s.d. Data are representative of two independent experiments.