Figure 5. Chemical inhibition of Mre11, a central MRE11-RAD50-NBS1 (MRN) complex component, promotes particulate matter (PM)-induced cytokine production. Wildtype bone marrow–derived macrophages (BMDMs) were incubated with and without the MRN complex inhibitor mirin (administered dose of 100 μM) for 2 hours, then were treated with PM (100 μg·mL-1) for an additional 24 hours. (A) The relative levels of Cxcl1, Cxcl2 and Ifn-γ mRNA transcripts were determined using quantitative PCR. (B) The protein levels of Cxcl1, Cxcl2 and Ifn-γ in the culture supernatants were measured using ELISA. Data are presented as means ± SEMs across at least 3 independent experiments. *p < 0.05; **p < 0.01.