SRA/CD204 dampens TLR4 agonist-stimulated inflammatory response in DCs. (A) Increased SRA/CD204 expression during DC differentiation and activation. BM cell culture in the presence of GM-CSF was analyzed for SRA/CD204 expression by immunoblotting. Day 8 WT BM-DCs were treated with LPS overnight. (B) Increased SRA/CD204 expression in APCs in response to LPS stimulation in vivo. WT mice were challenged with 10 μg of LPS by tail vein injection. Splenic DCs and Mφ were isolated using magnetic beads 48 hours later, and stained for SRA/CD204 expression (broken line, isotype control; solid line, no LPS treatment; gray filled, LPS treatment). (C) Increased up-regulation of costimulatory molecules in SRA^−/− splenic DCs. After LPS challenge, splenic DCs were isolated and stained with antibodies for MHC class II and costimulatory molecules. Fold increase in mean fluorescence intensity (MFI) is shown. Data shown are representative of 3 experiments. (D) Representative histogram profiles showing higher levels of CD86 in SRA^−/− splenic DCs after LPS stimulation in vivo (open histogram, no LPS treatment; gray histogram, LPS treatment). (E) Enhanced LPS-induced gene transcription of inflammatory mediators in SRA^−/− DCs. BM-DCs were stimulated with LPS (100 ng/mL) for 4 hours or overnight. Total RNA was prepared and subjected to RT-PCR analysis using specific primers. β-Actin was used as an internal control.