upregulated ITAM-mediated responses, such as rheumatoid arthritis, allergies, asthma, lupus, etc., our findings and other reports point to the importance of Syk in regulation of TLR4 responses, particularly by host-derived ligands, and development of chronic inflammatory diseases, such as atherosclerosis. Indeed, a very recent report by Hilgendorf et al. [31] demonstrates that administering fostamatinib attenuates atherosclerosis in Ldlr2/2 mice fed a high-cholesterol diet. The results of the current study as well as macrophage-specific Syk2/2 mice generated in our laboratory will be useful in addressing mechanisms involved in Syk-dependent chronic inflammation and atherosclerosis. Supporting Information Figure S1 ERK1/2 phosphorylation in Adeno-Cre/ Sykflox/flox macrophages stimulated with mmLDL. Resident peritoneal macrophages from Sykflox/flox mice were infected with adenovirus expressing either GFP or Cre for 48 hours at 500 MOI and then incubated with media or 50 mg/ ml mmLDL for 15, 30 or 60 min. Cell lysates were separated on Nu-PAGE and immunoblotted with antibodies against Syk, phospho-ERK1/2 or GAPDH. (TIF) Figure S2 Lack of p65 phopshorylation in response to mmLDL. WT and Syk2/2 BMDM were incubated with media or mmLDL (50 mg/ml) for 15 min. Cell lysates were separated on SDS-PAGE and immunoblotted with antibodies against phospho- p65 and GAPDH. (TIF) Figure S3 Role of JNK, IKKe and ERK1/2 in phosphor- ylation of c-Jun and c-Fos in mmLDL-stimulated mac- rophages: Quantification of results presented in Fig. 2C. In vitro kinase assay in J774 macrophages. Cells were incubated with mmLDL (50 mg/ml) for indicated periods of time and then precipitated with anti-JNK, anti-IKKe and anti-ERK1/2 anti- bodies. 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(2010) Low Doses of Lipopolysaccharide and Minimally Oxidized Low-Density Lipoprotein Cooperatively Activate Macrophages via Nuclear Factor {kappa}B and PLoS ONE | www.plosone.org 7 February 2012 | Volume 7 | Issue 2 | e32378