CD14 Signaling Restrains Chronic Inflammation through Induction of p38-MAPK/SOCS-Dependent Tolerance
Figure 4
CD14 deficiency results in dysregulated p38-MAPK signaling and cytokine production in response to B. burgdorferi.
A) Equal protein from lysates of CD14+/+ and CD14−/− MΦ incubated with B. burgdorferi were separated by 10% SDS-PAGE, transferred to a nitrocellulose membrane and probed with phospho-p38 and β-actin antibodies. B) CD14 was knocked down using lentiviral transduction as in Figure 1B & C. MΦ were incubated with B. burgdorferi for 30 min and phospho-p38 and β-actin were detected as in Figure 4A. C) CD14+/+ MΦ were treated with DMSO, SB202190 (0.5 µM) or arctigenin (1 µM) for 30 min prior to incubation with B. burgdorferi and total RNA was analyzed by qPCR for inos and socs3. D) CD14+/+ MΦ were treated as described in (C), and culture supernatants were analyzed for TNF-α by CBA. E) CD14+/+ MΦ were treated with DMSO or increasing concentrations of arctigenin or SB202190 for 30 min prior to incubation with B. burgdorferi. Cell culture supernatants were collected 24 h p.i. and TNF-α was measured by CBA. F) CD14+/+ MΦ were treated with DMSO or increasing concentrations of SB203580 for 30 min prior to incubation with live B. burgdorferi or B. burgdorferi lysate (10µg/ml). Cell culture supernatants were assayed for TNF-α by CBA. Results represent mean±SEM from two to five independent experiments. *P<0.05, **P<0.01, ***P<0.001.