ABSTRACT
Objective To clarify the role of syk kinase in inflammasome activation in mouse peritoneal macrophages during Listeria monocytogenes (LM) infection. Methods Murine peritoneal macrophages were randomly divided into BAY treatment group, SB treatment group, WO treatment group, no treatment group and negative control group (NI). There were three wells in each group. The syk inhibitor BAY 117082, P38MAPK inhibitor SB203580 and PI3K inhibitor wotamine were used to treat murine peritoneal macrophages for 1h in BAY treatment group, SB treatment group and WO treatment group. Murine peritoneal macrophages were infected with LM for 24 h except NI group. The protein level of interleukin (IL)-18 in the supernatant was detected by ELISA kit. The activation condition of key molecule ASC in the infected-macrophages cyto-plasm was observed under fluorescence microscope. The phosphorylation levels of syk protein kinase at different time points during LM infection were determined by Western blot assay. Results There was no significant difference in IL-18 protein level before and after BAY treatment in NI group (P>0.05). The IL-18 protein level was significantly lower after LM infec-tion in BAY treatment group compared with that in no treatment group (P0.05). Meanwhile, the per-centage of ASC-speck positive cells was obviously diminished in BAY treatment group compared with that in no treatment group (P<0.01). The phosphorylation levels of syk were significantly increased in 5 min, 15 min and 30 min post-infection. Conclusion Syk kinase signaling is involved in the inflammasomes activation upon Listeria monocytogenes infection in mu-rine macrophages.