Mechanisms underlying trafficking of aged neutrophils during inflammation. Using multichannel flow cytometry, numbers of aged and nonaged neutrophils in bone marrow, blood, and lysates of different organs of WT, TLR-2^−/−, or TLR-4-mutant mice and of WT mice receiving intra-arterial injections of the CXCR4 inhibitor AMD3100, blocking anti-CXCL12 mAbs, the TLR-4 inhibitor TAK-242, or drug vehicle/isotype control antibodies upon IP injection of PBS or LPS were quantitatively analyzed as detailed in “Methods.” Results that have been normalized to controls are shown. Mean ± SEM for n = 4-5; ^#P < .05 vs PBS; *P < .05 vs drug vehicle/isotype control/WT.