Figure 3.

Interleukin-1-receptor-associated kinase-4 (IRAK-4)-deficient but not Toll/IL-1 receptor (TIR) domain-containing adaptor inducing IFN-β (TRIF)-deficient neutrophils have impaired mobilization of azurophilic granules in response to lipopolysaccharide (LPS). Peritoneal neutrophils from wild-type (WT), IRAK-4 knockout (IRAK-4^−/−) or TRIF-deficient (Trif^−/−) mice were stimulated with LPS (a) or heat-killed Listeria monocytogenes (HKLM), (b), or incubated in the absence of stimuli (NS) for 1 hr at 37°. Cells were analysed for myeloperoxidase (MPO) release as described in the Materials and methods section. Statistical analysis was performed using a one-tailed, paired Student’s t-test. #, not significant.