Comparison of proinflammatory LRP1 signaling in BMDMs. (A) BMDMs from WT C57BL/6J mice were pretreated with TLR4-neutralzing antibody (+TLR4-Ab, 5 µg/mL) or with vehicle (−TLR4-Ab) for 3 h and then with LPS (0.1 µg/mL), RAP (150 nM), LF (150 nM), or vehicle for 1 h. Separately, WT BMDMs that were not exposed to TLR4-Ab were treated with LPS (0.1 µg/mL) or RAP (150 nM), which had been boiled for 5 min. Equal amounts of cellular protein (20 µg) were subjected to immunoblot analysis to detect phospho-IκBα, total IκBα, and β-actin. (B) BMDMs were isolated from littermate mLRP1^+/+ and mLRP1^−/− mice. The cells from mLRP1^−/− mice were treated with h-El-tPA (12 nM), RAP (150 nM), or vehicle for 8 h. Cells from mLRP1^+/+ mice were treated with vehicle. RT-qPCR was performed to determine TNFα mRNA (mean ± SEM; n = 8; 1-way ANOVA with Tukey’s post hoc analysis). (C-E) WT BMDMs were treated with monomeric RAP (mRAP, 150 nM) or vehicle for 8 h. RT-qPCR was performed to determine mRNA levels for TNFα, CCL3, and IL-6. (F) WT BMDMs were treated for the indicated times with RAP (150 nM). Equal amounts of cellular protein (20 µg) were subjected to immunoblot analysis to detect phospho-IκBα, total IκBα and β-actin. **P < .01, ***P < .001.