Lipopolysaccharide from Rhodobacter sphaeroides Attenuates Microglia-Mediated Inflammation and Phagocytosis and Directs Regulatory T Cell Response

Figure 6

LPS-Rs skews T cell response with induction of Tregs cells. Splenocytes were treated with or without LPS-Rs followed by LPS treatment and cell proliferation was assayed by MTT assay after 72 hrs (a). T helper associated transcription factors: TBET, FOXP3, and ROR-γ (b) and cytokines IFN-γ, IL-10, and TGF-β (c) were assayed by RT-PCR after 48 hrs. The secretary IFN-γ, IL-17, and IL-10 from culture supernatant were analysed by ELISA after 72 hrs (d, e, and f). The differentially treated splenocytes after 72 hrs were fixed, surface stained with FITC-CD4 mAb and APC-CD25 mAb followed by permeabilization and intracellular staining with PE-Foxp3 mAb, and analyzed by flow cytometry. The CD4⁺CD25⁺ cells were gated and Foxp3 expression was determined and expressed as percentage change (g). The error bars represent the mean ± SEM from three independent experiments ( versus control and versus LPS). UN: untreated; LPS: lipopolysaccharide from Escherichia coli 055 : B5 (1 µg/mL); RS: lipopolysaccharide from Rhodobacter sphaeroides (0.5–5 µg/mL).