CD14 Mediates Binding of High Doses of LPS but Is Dispensable for TNF-α Production
Figure 6
Occupation of SR by dextran sulfate upregulates sLPS-induced TNF-α production with CD14 participation. RAW264 cells were pretreated with 50 μg/mL dextran sulfate or 50 μg/mL chondroitin sulfate or 10 μg/mL anti-CD14 or 10 μg/mL isotype-matched rat IgG2b (cIgG) or combination of the agents, as indicated, and subsequently were exposed to 10–1000 ng/mL of sLPS (37°C). Generation of TNF-α (a), MIP-2 (b), and RANTES (c) was estimated in culture supernatants by ELISA tests. Arrows directed upwards point to the enhancement of cytokine production stimulated by 100 or 1000 ng/mL of sLPS in the presence of dextran sulfate while arrows directed downwards indicate the inhibition of cytokine generation by the anti-CD14 in comparison to cells exposed to sLPS accompanied by dextran sulfate. Data shown are mean ± SEM from three or four experiments each run in triplicates. *Significantly different from cells exposed to chondroitin sulfate and sLPS; #significantly different from cells exposed to dextran sulfate and sLPS.
